Dresser-Rand - MANUAL 7SHF162

SERVICE MANUAL
(1) 7.0-INCH STROKE TYPE HOSS

NATURAL GAS COMPRESSOR
15.0 + 15.0 + 9.50 + 9.50 X 7HOSS4
ENERFLEX ENERGY SYSTEMS, INC

(PDVSA)
CUSTOMER P.O. NO. 4500036132

SPARES P.O. NO. A0062558
D-R GFC ORDER: C2314

(121955/90032109)
UNIT SERIAL NUMBERS:

FRAME: 7SHF162
CYLINDERS: 7SHC401 - 404
Gas Field Compressors

JANUARY 2013
© Dresser-Rand Company 2013

Printed in U.S.A.
Form PG-4792
February, 2001
How To Navigate The DRESSER-RAND

Electronic Service Manual
1. Use the following illustrations (Figure 1.) for those who have the Adobe Acrobat
on their computers. Figure 1A. is for those opening the CD with the Acrobat
Reader supplied on the disc. Numbered descriptions are for quick location,
identification and description of tools to navigate the electronic service manual on
both illustrations.
14
1 5 7
12 13 8
15
6
9
3
2
6
10
8
5
11
Figure 1.
1. Bookmark Icon – Move mouse arrow to and click on to show or hide bookmarks.
2. Bookmarks – Click on to move to section represented by the specific bookmark.
3. (+) Hidden Subheadings – Click on to show hidden sub-headings (bookmarks).
4. (-) To Hide Subheadings – Click on to hide sub-headings (bookmarks).
5. Page Forward>, Page Back< - Click on to move forward or back one page at a time.
6. First Page/Last Page arrows – Click on to move to first or last page of the book.
7. Retrace Steps Ahead & Back arrows – Click on to retrace your steps ahead & back.
8. Scroll Up/Down arrows for page – Press mouse button to move pages vertically.
9. Scroll Up/Down box for page – Move box to move pages vertically.
10. Scroll Right/Left arrows for page – Press mouse button to move pages horizontally.
11. Scroll Right/Left box for page - Move box to move pages horizontally.
12. Page Sizing Icons - Click on specific icon to make pages larger and smaller.
13. Find Icon – Click on icon to show Find Command Box.
14. Hand Icon – Click on and use to use links for additional help navigating instructions.
Use hand tool to click on numbers in Figure 1., or items in list below for further
information.
15. Magnifier Icon – Click on icon to bring objects closer and move them away.
Form PG-4792 How To Navigate The Electronic Service Manual
1A. Use the following illustration Figure 1A. for those opening the CD with the
Acrobat Reader supplied on the disc. The previous list of numbered descriptions are
for quick location, identification and description of tools to navigate the electronic
service manual on this illustration also.
1 15
5 7
14 12 13 8
6
3 2
9
10
8
11 Will appear when page overfills frame
Figure 1A.
Note:
Only the Hand tool (14) and Magnifier tool (15) you will be
using are located in different locations in the two
arrangements. They are located at the top with all the
other tools in (Figure 1A.). They are located on the left
hand side with the construction tools in (Figure 1.). There
is no tool bar on the left hand side of the (Figure 1A.)
arrangement at all.
2
How To Navigate The Electronic Service Manual Form PG-4792
2. BOOKMARKS - Getting To Sections
A. The Bookmarks, which will help you navigate the DRESSER-RAND Electronic
Service Manual, can be opened or closed in two ways.
1. By bringing the mouse arrow to the icon at the top of the page and clicking’
the left mouse button once. If closed it will open and if open, it will close.
The Bookmarks Icon represents a white sheet of paper, with a blank (gray)
box attached to the left side, indicating the Bookmarks. (See Figure 2.)
2. They can also be opened or closed by going to “Window” at the top of the
page. Click on “Window” and go to “Show Bookmarks” to open. If the
bookmarks are already open and you want to close them, go to ”Window”
then “Hide Bookmarks” with the mouse arrow and click on it. (See Figure 2.)
2.A.2. - Click on “Window” and Go To

“Show/Hide Bookmarks” as needed.
2.A.1.
Bookmark
Icon
Figure 2.
3
3. The Bookmarks are similar to a table of contents. When the Hand Tool
points with one finger, click the left mouse button on a particular heading
(Bookmark), you will be taken immediately to that subject page or the first
page of the desired section. (See Figure 3.)
4. Any bookmark connected to a small box with a plus (+) sign indicates there
are additional sub-headings hidden under that bookmark. (See Figure 3.)
a. Click on the plus (+) sign to show the sub-headings.

b. Click on the minus (-) sign to hide the sub-headings.
c. Clicking on any of the sub-heading bookmarks will also take you to
the beginning page of those sub-sections.
3.A.
2.B.
3.A.3.
2.A.2.
2.B.1
2.A.3.b.
2.A.3.a. 3.A.3.
3.A.
2.B.
Figure 3.
B. Moving Through Pages (Horizontally & Vertically) The arrowheads at the bottom
and side of the page display window will move the information left or right (horizontal
arrowheads) or up or down (vertical arrowheads) for scrolling the document.
1. The boxes in the lane between the scroll up & down, right & left arrows will
allow you to scroll in that direction by moving the box between the arrows.
Use the mouse arrow to move the box.
a. The up/down box will allow you to scroll through the pages. (Fig. 3)
b. The box between the right/left arrows allows you to move to the right
or left of the page. (See Figure 1.)
4
Note
Similar arrows and boxes are found in the Bookmark window

allowing the same scrolling in that area.
Note
As you scroll through the pages using the vertical arrowheads,

the page numbers (indicating the page you are on) appear in
two places, on the side near the arrowheads and in a meter on
the bottom of the document. However, these are the total
pages. Look at the bottom of the pages you are viewing to
see where you are in that particular section.
3. NAVIGATING IN SECTIONS & BETWEEN SECTIONS
A. Moving Within Sections - The arrowheads at the top of the display screen or at the
bottom of the screen, near the page number display, will help you move within and
between sections of the book. By clicking on the arrowheads at the top of the page
or at the bottom, near the page display, you can move through the manual a page at
a time. (See Figure 3.)
1. By using the arrowhead facing to the right you can move a page at a time
toward the back of the book.
2. By using the arrowhead facing to the left you can move a page at a time
toward the front of the book.
3. The arrowheads with the lines in front of them will take you to the last page of
the book (the arrowhead facing right with a line in front) or the first page (the
arrowhead facing left with a line in front).
Note
As with the retracing arrows at the top of the page, when you
can go no farther, the arrow turns gray.
4. TRACKING BACK AND FORTH THROUGH A SEQUENCE OF PAGES
A. The arrows (with extensions at the top of the page) will take you backward and
forward retracing your steps through the sequence of pages you have traveled
through the book. (See Figure 3.)
Note
As with the paging arrowheads at the top of the page, when

you can go no farther, the arrow turns gray.
5
5. SIZING PAGES
A. The page may be sized in the screen using the 3 icons at the top of the page.
(See Figure 4.)
1. Each icon is represented as a piece of paper with the upper right corner of
the paper turned over.
a. The first icon to the left makes the page being displayed actual size.
b. The middle icon fits the full page into the screen.
c. The third icon to the right fits the full page width to the screen.
5.B.&C.
4.A. 5.A. 6.A.
5.D.
Figure 4.
B. The page may be sized by using the tools in the “View” window. (See Figure 4.)
1. The size may be adjusted by selecting;

a. Fit in Window
b. Actual Size
c. Fit Width
d. Fit Visible (Full page width, excluding margins)
6
C. Zoom Commands, also in the “View” window, may also be chosen to change page
size. (See Figure 4.)
1. “Zoom In” makes image larger.
2. “Zoom Out” makes image smaller.
3. “Zoom To” provides a command box to set the image size at a percent (%) of
normal size (100%).
D. A size gauge showing percent (%) in the lower left of the page window can be used
to change page size.
1. Click the mouse arrow on the arrowhead on the right of the percent (%) gage.
a. A window with a choice of percentages is given.
b. The sizing choices
• Fit in Window
• Actual Size
• Fit Width
• Fit Visible
E. The magnifier tool, represented by a magnifying glass on the upper tool bar may also
be used to accomplish this. (See # (15) on Illustrations 1. And 1A.)
6. LOCATING SPECIFIC INFORMATION
A. Use the Binoculars icon (Find) on the right side of the top tool bar. This process
works within a single document and reads every word on every page. (See Figure 3.)
1. Click the Binoculars icon.
2. Enter the word or word combination sought into the “Find What:” box.
a. There are three boxes you may check to guide your search.
• Match Whole Word Only – check this to match complete word
• Match Case – Check this to match heading or body case
• Find Backwards – Check this to search from back of book
3. Click the “Find” button.
7
EXTREMELY IMPORTANT….PLEASE READ THIS!
TO THE D-R EQUIPMENT OWNER/OPERATOR:
You, as the holder of this manual or CD, are responsible for the maintenance of this
document. The safe, proper and efficient installation, operation, and maintenance
of your Dresser-Rand equipment is dependent on your maintenance of this
document.
It is extremely important that you complete and mail/email the form below. Your
action will insure that future updates and revisions are sent directly to you. Holders
of the hard copy (paper) manuals will receive only the required pages to update the
document along with instructions for removing and/or inserting new pages. Holders
of CD manuals will receive a complete replacement CD.
MANUAL HOLDER INFORMATION - FIRST
COMPANY:
HOLDER’S NAME:
ADDRESS 1:
ADDRESS 2:
CITY, STATE, ZIP:
COUNTRY:
UNIT SERIAL NO.
PHONE: (____)___________ FAX: (____)___________ Email: _______________________
MANUAL HOLDER INFORMATION - SECOND
COMPANY:
HOLDER’S NAME:
ADDRESS 1:
ADDRESS 2:
CITY, STATE, ZIP:
COUNTRY:
UNIT SERIAL NO.
PHONE: (____)___________ FAX: (____)___________ Email: _______________________
DRESSER-RAND, Painted Post Operations, 100 Chemung Street, Painted Post, NY 14870
Phone: (607) 937-2011, FAX: (607) 937-2043, Email: ppt_techpubs@dresser-rand.com
SERIAL NUMBER: 7SHF162
ENTERED DESCRIPTION OF CHANGE REVISION

BY ECN/CSS/REVAMP DATE
SKJ ORIGINAL ISSUE JAN. 2013
FRONT MATTER
CONTENTS
SAFETY PRECAUTIONS ..................................................................................... PG-662-F
SAFETY LABELS.................................................................................................. PG-2914-F
PLACEMENT DRAWING ...................................................................................... G12157C
SERVICE CENTERS ............................................................................................ PG-2697-P
TECHNICAL COMPRESSOR TRAINING............................................................. PG-2551-E
SERVICE LITERATURE READER SURVEY ....................................................... PG-2915-A
METRIC CONVERSIONS ..................................................................................... PG-732-D

Form PG-0662-F
November, 2007
SAFETY PRECAUTIONS
Safety Information
WARNING
DO NOT OPERATE THIS EQUIPMENT IN EXCESS OF ITS RATED
CAPACITY, SPEED, PRESSURE AND TEMPERATURE, NOR
OTHERWISE THAN IN ACCORDANCE WITH THE INSTRUCTIONS
CONTAINED IN THIS SERVICE MANUAL. OPERATION OF THE
EQUIPMENT IN EXCESS OF THE CONDITIONS SET FORTH IN THE
SALES CONTRACT WILL SUBJECT IT TO STRESSES AND
STRAINS WHICH IT WAS NOT DESIGNED TO WITHSTAND.
FAILURE TO HEED THIS WARNING MAY RESULT IN AN ACCIDENT
CAUSING PERSONAL INJURY OR PROPERTY DAMAGE.
WARNING
READ CAREFULLY AND UNDERSTAND THIS SERVICE MANUAL
BEFORE INSTALLING OR OPERATING THE COMPRESSOR.
This service manual contains important instructions and information on the installation,
operation and servicing of Dresser-Rand Model compressors. THE IMPORTANCE OF
GETTING THIS SERVICE MANUAL INTO THE HANDS OF THE PERSON IN
CHARGE OF INSTALLING THE COMPRESSOR CANNOT BE OVEREMPHASIZED. All
personnel involved in the installation, operation and servicing of the compressor should
have access to this service manual and be familiar with its contents. Strict adherence to
these instructions will be repaid by satisfactory compressor performance and acceptable
upkeep costs.
Do not remove the stainless steel nameplates that are attached to the machine. These
plates give serial numbers that are necessary when communicating with Dresser-Rand
about the equipment. Also, do not remove safety labels. If these labels are removed or
defaced, new ones should be obtained from Dresser-Rand Company.
REFER ALL COMMUNICATIONS TO THE NEAREST DRESSER-RAND COMPANY

OFFICE.
Safety Precautions PG-0662-F
Dangers, warnings and cautions appearing throughout this service manual are of
paramount importance to personnel and equipment safety. Prior to any attempt to operate,
maintain, troubleshoot, or repair any part of the compressor, all DANGERS, WARNINGS and
CAUTIONS should be thoroughly reviewed and understood. Refer to the Safety Summary that
starts on the next page. The information immediately following defines "signal words" as they
are used in this manual.
SIGNAL WORDS ARE USED TO IDENTIFY LEVELS OF HAZARD SERIOUSNESS. THEIR

SELECTION IS BASED ON THE LIKELY CONSEQUENCE OF HUMAN INTERACTION WITH
THE HAZARD IN TERMS OF:
● DEGREE OF SEVERITY (minor injury, severe injury, death)
● THE PROBABILITY OF SEVERITY (will result, could result)
DANGER
The word DANGER signifies immediate hazards that WILL result in severe
personal injury or death. In the service manual, this should be construed
to be a VERY STRONG Warning (see below).
WARNING
The word WARNING refers to hazards or unsafe practices that COULD
result in severe personal injury or death. This is found quite often in the
service manual due to its association with unsafe practices.
CAUTION
The word CAUTION refers to hazards or unsafe practices that COULD
result in minor personal injury, or product or property damage. This word
is found frequently in the service manual due to the fact that bad mainte-
nance practices or procedures can so often result in damage to the com-
pressor. Because what constitutes a "minor" injury is open to debate, we
have upgraded many CAUTIONS to WARNING.
NOTE
NOTES are used to highlight certain operating or maintenance conditions or

statements that are essential but not of a known hazardous nature, as would be
indicated by DANGER, WARNING or CAUTION.
2
PG-0662-F Safety Precautions
SAFETY SUMMARY
The following safety precautions are being recommended only in regard to the
compressor and other Dresser-Rand supplied equipment (ex: motors, consoles, etc.). Abide by
all OSHA and all other applicable safety regulations, including all site-specific safety and work
procedures.
The installation, operation and maintenance of a compressor and auxiliary components

may present certain hazards that are unique to this type of equipment. The following list of
safety precautions must be thoroughly read and reviewed by all personnel prior to working with
or on the compressor equipment and systems. These general statements are expanded upon
in the sections of the manual appropriate to their application. Failure to heed these
statements can result in an incident causing property damage, personal injury or death.
● All electrical motor and control wiring must be carefully installed in accordance with the
National Electric Code, the Occupational Safety and Health Act of 1970 (OSHA) and
any other code requirements at the installation site.
● Piping subject to temperatures in excess of 175ºF (80ºC) which may be touched by

personnel must be suitably guarded or insulated.
● It is imperative that all gases lighter or heavier than air, active or inactive, toxic,
combustible, obnoxious, objectionable, or in any way harmful to personnel or
equipment, be piped away from the compressor. There must be no manifolding of vent
tubing or piping; nor can back pressure be allowed to develop in any vent line. Gases
may be re-circulated as required by the process, but in any case must be controlled
and/or disposed of in accordance with OSHA regulations and local pollution laws.
● The compressor must be fitted with pressure relief valves or rupture disks to limit the
discharge pressures to a safe maximum. NEVER install an intervening valve between a
compressor cylinder and the pressure relief valve or rupture disk.
● Pressure relief valves must have their settings tested at least once a year, and more
often under extreme operating conditions, using an appropriate bench test.
● If a pressure relief valve or rupture disk blows during operation, stop the unit
immediately and determine the cause.
• Compressor manufacturers utilize elastomer seals (O-rings) found in today’s

compressor frames, distance pieces, compressor cylinders and valves. When selecting
O-rings the process conditions must be thoroughly understood. At high pressure, high
mole weight and even some lower mole weight gas applications, gases can diffuse into
the O-ring. Upon rapid blowdown or decompression, the impregnated gas may exit too
quickly causing the O-ring to “blister”, thus leading to process gas leakage upon re-start.
For high-pressure, high mole weight and even some lower mole weight gas
applications, O-ring material selection, O-ring hardness (durometer generally 85 – 90)
and decreased blowdown rate (psi / min.) have alleviated problems with leakage due to
“blistering”. Dresser-Rand Co. can provide guidance for O-ring or seal selection to
reduce the possibility of O-ring leakage due to “blistering”.
3
Safety Precautions PG-0662-F
● Pressure relieving devices that are vented to the atmosphere must have their outlet
connections directed away from operator stations.
● Rotating equipment must not be placed in operation unless adequate safeguards have
been provided to protect operating personnel.
● Service on a machine shall always start with cleaning the floor and the outside of the
machinery to remove oil that could cause maintenance personnel to slip.
● Whenever a compressor is shut down for repairs, positive steps must be taken to
prevent the prime mover from being inadvertently energized and started. Equipment
being worked on should be “Locked Out” and “Tagged Out” to ensure against
inadvertently providing power and accidentally starting. In addition, a warning sign
bearing the legend "WORK IN PROGRESS-DO NOT START", or similar wording, shall
be attached to the starting equipment.
● Whenever the compressor is shut down because overheating is suspected, a minimum

period of 30 minutes must elapse before the crankcase is opened. Premature opening
of the crankcase can result in a crankcase explosion.
● Prior to opening the compressor, or undertaking a major overhaul, the unit must be
positively blocked against rollover and movement of the running gear. When the unit is
equipped with a flywheel locking device, this device must be used to prevent rollover.
Blocking of the crankshaft or crossheads is an alternate method of preventing accidental
rollover.
● Never open a compressor cylinder or any other part of the compression system without
first completely relieving all pressure within the compressor cylinders, piping, vessels
and coolers; and taking all necessary precautions to prevent accidental pressurizing of
the system.
● Compressors handling toxic or flammable gases must be isolated from the process
piping by means of blinds, or double valves and bleeders, when major maintenance is
required. Before opening such compressors, the equipment MUST be purged or
evacuated.
● Incorrect placement of the inlet and discharge valves in the cylinders can cause an ex-
tremely hazardous condition. INSTALLING AN INLET VALVE IN A DISCHARGE
VALVE PORT, OR INSTALLING A DISCHARGE VALVE UPSIDE DOWN, MAY CAUSE
EXCESSIVE PRESSURE IN THE CYLINDER RESULTING IN RUPTURE AND/OR AN
EXPLOSION.
● Discharge valve ports usually are made slightly smaller at the minor diameter below the
valve gasket seat; this is called "polarization". When an inlet valve is installed in a
discharge port by mistake, it will not fit down into the port properly and the mechanic will
be alerted to the error.
● In many cases, the inlet valve stop plates have lugs that will prevent an inlet valve from
being installed in a discharge valve port by mistake; this is another type of "polarization".
The minor diameter of the discharge port is slightly smaller so the inlet valve will not fit
properly, alerting the mechanic to the error.
4
PG-0662-F Safety Precautions
● If IN DOUBT as to whether a valve is inlet or discharge, or as to which cylinder valve

ports receive inlet or discharge valves, CHECK WITH YOUR SUPERVISOR.
● Corrective action must be taken when the piston rod pressure packing vent gas leakage
is excessive, or when there is a sudden increase in the leakage rate.
● After any maintenance or overhaul of the compressor, the unit must be barred through
at least one complete revolution to ensure that there are no mechanical obstructions
within the machine.
● A manual bar and fulcrum and/or a hydraulic or pneumatic barring rig may have been
provided as a means of rotating the compressor crankshaft during installation, during
maintenance, prior to start-up after maintenance or overhaul, and at any other time
exact positioning of the running gear is required. Compressor cylinders must be
depressurized to atmospheric pressure before barring. Compressor pistons will move to
crank end dead center as an equilibrium condition due to the difference in crank end
and head end piston surface areas if exposed to the process gas pressure. Failure to
depressurize the compressor cylinders prior to barring may result in unexpected rotation
that can cause personal injury.
● Established operating and maintenance procedures, as well as basic safety

precautions, must be reviewed with the operating and maintenance personnel at regular
intervals, not to exceed six months. Newly assigned operators must be thoroughly
trained in the safe operation of this equipment before they are permitted to operate it.
● Whenever an outer head is removed from the compressor cylinder, make certain that
the piston vent hole(s), if used, located in the outer face of the piston are open and that
the piston does not contain pressure. If the compressor has been handling a flammable
or toxic gas, appropriate precautions shall be taken before clearing a vent hole that has
become plugged.
● Never use an air impact wrench for ANY tightening of critical fasteners. An impact
wrench cannot accurately impart the proper bolt or stud pre-stress. See CHAPTER 5 of
this manual for detailed fastener tightening requirements and procedures.
● Special attention should be paid to all detailed DANGER, WARNING and CAUTION
statements located throughout this manual, and to all SAFETY LABELS affixed to the
equipment.
5
Form PG-2697-P
June, 2009
Service Centers...
UNITED STATES
State-City-Telephone-Fax Address
ALASKA – Kenai Dresser-Rand Service Center
Tel: (907) 776-8225 46645 Kenai Spur Highway Ste. B
Fax: None Kenai, AK 99611
CALIFORNIA – Chula Vista Dresser-Rand Service Center
Tel: (619) 656-4740 1675 Brandywine Ave., Suite F
Fax: (619) 656-4819 Chula Vista, CA 91911
CALIFORNIA – Concord Dresser-Rand Service Center
Tel: (925) 356-5700 2615 Stanwell Drive
Fax: (925) 681-3170 Concord, CA 94520
CALIFORNIA – Los Angeles Dresser-Rand Service Center
Tel: (310) 223-0600 18502 Dominguez Hills Drive
Fax: (310) 223-0607 Rancho Dominguez, CA 90220
FLORIDA – Atlantic Beach Dresser-Rand Service Center
Tel: (904) 249-0160 482 A Stewart Street
Fax: (904) 249-0909 Atlantic Beach, FL 32233
ILLINOIS – Chicago - Naperville Dresser-Rand Service Center
Tel: (630) 961-1990 1101 Frontenac Road
Fax: (630) 961-5849 Naperville, IL 60563-1746
LOUISIANA – Baton Rouge Dresser-Rand Service Center
Tel: (225) 275-6550 2444 Dumont Drive
Fax: (225) 275-6732 Baton Rouge, LA 70815
LOUISIANA – Jena Dresser-Rand, Arrow Sales and Service
Tel: (318) 992-8484 1550Hwy. 84 East
Fax: (318) 992-0045 Jena, LA 71342
MISSOURI – Louisiana Dresser-Rand, Arrow Sales and Service
Tel: (573) 754-4557 520 Kelly Lane
Fax: : (573) 754-4789 Louisiana, MO 63353
OHIO – Cincinnati - Hamilton Dresser-Rand Service Center
Tel: (513) 874-8388 8655 Seward Road
Fax: (513) 874-9236 Hamilton, OH 45011
OKLAHOMA – Kiefer Dresser-Rand, Arrow Sales and Service
Tel: (918) 321-3690 14963 S. 49th W. Ave.
Fax: (918) 321-6075 Kiefer, OK 74041
OKLAHOMA – Tulsa Dresser-Rand Service Center
Tel: (918) 835-8437 1354 South Sheridan Road
Fax: (918) 832-7046 Tulsa, OK 74112-5416
PENNSYLVANIA – Philadelphia - Horsham Dresser-Rand Service Center
Tel: (215) 441-0400 203 Precision Road
Fax: (215) 672-8239 Horsham, PA 19044
TEXAS – Houston Dresser-Rand Service Center
Tel: (713) 346-2257 - (713) 620-3254 1415 Lumpkin Road
Fax: (713) 827-0353 Houston, TX 77043
TEXAS – Midland Dresser-Rand Service Center
Tel: (432) 620-0477 2309 East I-20
Fax: (432) 620-0499 Midland, TX 79701
PG-2697-P SERVICE CENTERS
UTAH – North Salt Lake City Dresser-Rand Service Center

25 North 400 West
North Salt Lake City, UT
VIRGINIA – Chesapeake Dresser-Rand Service Center
Tel: (757) 494-3800 1101 Cavalier Boulevard
Fax: (757) 487-9450 Chesapeake, VA 23323
WASHINGTON – Seattle Dresser-Rand Service Center
Tel: (206) 762-7660 225 S. Lucile Street
Fax: (206) 762-1298 Seattle, WA 98108-2480
International Service Centers... Next Pages

Service Centers...
INTERNATIONAL
Country-City-Telephone-Fax Address
ANGOLA – Luanda Dresser-Rand Global Services Inc.
Rua da Cercania do porto no.16
Edifficio SGEP, Barrio da Boavista
Luanda, Angola
BRAZIL – Campinas Dresser-Rand Brazil
Tel: 55-19-3-728-8600 Rua Altino Arantes, 1010
Fax: 55-19-3-227-8200 13051-110 Campinas – SP
Brazil
CANADA – Edmonton – Alberta Dresser-Rand Canada Inc.
Tel: (780) 436-0604 9330 – 45 Avenue
Fax: (780) 436-0532 Edmonton, Alberta Canada
T6E 6S1
CANADA – Sarnia, Ontario Dresser-Rand Canada Inc.
Tel: (519) 346-0604 396McGregor Rd. S.
Fax: (519) 346-1955 Sarnia, Ontario Canada
N7T 7H2
ENGLAND – Peterborough Dresser-Rand Company Ltd.
Tel: 173-332-5518 56 Papyrus Road
Fax: 173-329-2300 Werrington Industry North
Peterborough PE 45BH England
FRANCE – LeHavre Dresser-Rand SA
Tel: 33-2-35-25-5225 31 Boulevard Winston Churchill
Fax: 33-2-35-25-5366 Cedex 7013
Lehavre 76080 France
GERMANY – Bielefeld Dresser-Rand Nadrowski
Tel: 49-521-1085-0 Turbinen GmbH
Fax: 49-521-1085-199 33619 Bielefeld
Germany
GERMANY – Oberhausen Dresser-Rand GmbH
Tel: 49-208-65-6020 Brinkstrasse 21
Fax: 49-208-65-3900 D-46149 Oberhausen
Germany
2
SERVICE CENTERS PG-2697-P
INDONESIA – Banten – Cilegon PT Dresser-Rand Services Indonesia

Tel: 62-254-310-903 Standard Factory Building Nos. B1, B2, B3
Fax: 62-254-310-907 JI. Eropa II Kawasan Industri
Email: ptdrsi@dresser-rand.com Krakatau Cilegon,
Banten, Indonesia 42436
ITALY – Genoa Dresser-Rand Italia Srl
Tel: 39-0185-938000 Localita’ Brughiera
Fax: 39-0185-938004 16030 Tribogna
Genoa, Italy
MALAYSIA – Terengganu Dresser-Rand & Enserv Svcs. Sdn Bhd
Tel: 60-9-868-4746/4748 Lot A6, Kawasan Perindustrian MIEL
Fax: 60-9-868-4844 Jakar Phase III
24-Hour Hotline: 60-12-608-0114 24000 Kemaman
Terengganu, Malaysia
THE NETHERLANDS – Spijkenisse Dresser-Rand BV
Tel: 31-181-61-7811 P.O. Box 66
Fax: 31-181-62-0403 3200 AB Spijkenisse
The Netherlands
NIGERIA – Rivers State Dresser-Rand Nigeria Ltd.
Tel: 234-84-611651 St. Clair, Kilometer 6
ABA Expressway
Port Harcourt
Rivers State, Nigeria
NORWAY – Kongsberg Dresser-Rand A. S. Client Support Centre
Tel: 47-322-87070 P.O. Box 1010
Fax: 47-322-87080 NO-3601 Kongsberg
Norway
PEOPLES REPUBLIC OF CHINA (PRC) Dressor-Rand Engineered Equipment
Tel: 86-21-6591-8050 (Shanghai) Ltd.
Fax: 86-21-6591-7720 510 North Guo Quan Road Baoshan
Mobil: 86-13-9019-99220 District
Shanghai, 200439
Peoples Republic Of China, (PRC)
SCOTLAND – Aberdeen Dresser-Rand U.K.
Tel: 44-1224-87-9445 Hareness Circle
Fax: 44-1224-89-4616 Altens Industrial Estate
Aberdeen AB12 3LY
Scotland, UK
UZBEKISTAN – Chirchik UZ Dresser-Rand
Tel: 998-7071-64922/64923 8 Mendeleev Street
Fax: 998-7071-64929 Chirchik
702100 Uzbekistan
VENEZUELA – Maracaibo Dresser-Rand S.A.
Tel: 58-261-736-1533 Av. 66 No. 146-458
Fax: 58-261-736-2114 Zona Industrial
Maracaibo, Edo. Zulia Venezuela
3
The Product Training Department of Dresser-Rand's Reciprocating Products Form PG-2551-E
Division offers instructional programs which provide a practical approach to
October, 2001
learning techniques for installing, operating, maintaining, repairing and
troubleshooting gas engines and reciprocating compressors. Both factory
programs and machine-specific on-site programs are designed for mechanics,
maintenance supervisors, mechanical and process engineers, and operators.
These programs are conducted by full-time instructors, Technical Service
Engineers, and Field Service Representatives.
For more information, contact your Dresser-Rand Sales Representative or the

Reciprocating Products Division Product Training Department at Painted Post,
NY. Phone: (607) 937-2797/2303/2509/2104. OR www.dresser-rand.com,
E-mail: training@dresser-rand.com
Form PG-732-D
February, 1998
METRIC CONVERSION EQUIVALENTS
— U.S. TO METRIC —
The metric conversion equivalents listed below

represent the more commonly used measuring
units in the engine and compressor industry.
Multiply By To Obtain
inches (in) 25.4 millimetres (mm)
pounds (lbs) 0.454 kilograms (kg)
gallons (gals) 3.785 litres (L)
horsepower (HP) 0.746 kilowatts (kW)
British Thermal Units (Btu) 1055 joules (j)
degrees Fahrenheit (°F) 0.556 (°F - 32) degrees Celsius (°C)
pounds per square inch (psi) 0.0703 kilograms per square

centimetre (kg/cm2)
6.895 kilopascal (kPa)
0.069 bar
cubic feet per minute (CFM) 0.0283 cubic metres per minute
(m3/min)
gallons per minute (GPM) 3.785 litres per minute (L/min)
torque in foot-pounds (ft-lbs) 1.356 newton metres (N•m)
0.138 kilogram metres (kg-m)
Saybolt Seconds Universal (SSU):

50-100 SSU (0.226 x SSU) - (205.3 ÷ SSU) kinematic viscosity,
100-350 SSU (0.22 x SSU) - (147.7 ÷ SSU) centistokes (cSt)
over 350 SSU @ 100°F (40°C) SSU x 0.21576
over 350 SSU @ 210°F (100°C) SSU x 0.21426
COMPRESSOR INSTRUCTIONS
GFC ORDER C-2314
(121955/90032109)
CONTENTS
HOSS COMPRESSOR INSTRUCTIONS ............................................................. PG-4875-C
15.0-INCH CYLINDER INSTRUCTIONS .............................................................. HIHI0003T5

-PISTON/RING & END CLEARANCES
-SPECIAL CYLINDER TORQUE VALUES
9.50-INCH CYLINDER INSTRUCTIONS .............................................................. HIHI0003T1

-PISTON/RING & END CLEARANCES
-SPECIAL CYLINDER TORQUE VALUES
SUPERBOLT TORQUE NUT ................................................................................ PG-2818-L

Form PG-4875-C
November, 2012
INSTRUCTIONS
for
OPERATING
and
SERVICING
HOSS
COMPRESSOR
GAS FIELD COMPRESSORS
© Dresser-Rand Company 2012

Printed in U.S.A.
Front Matter PG-4875-C (HOSS)
FOREWORD
This manual is divided into two major sections.
(1) FRONT MATTER; containing WARNING, FOREWORD, SAFETY SUMMARY,

STATEMENT OF WARRANTY, LIMITATIONS of LIABILITY and other comments of
interest to our customers.
(2) TECHNICAL SECTION; consisting of five chapters.
 CHAPTER 1, INTRODUCTION
 CHAPTER 2, LUBRICATION
 CHAPTER 3, OPERATING AND TROUBLESHOOTING
 CHAPTER 4, MAINTENANCE
 CHAPTER 5, GENERAL DATA AND SPECIFICATIONS
Do not remove the stainless steel nameplates that are attached to the machine. These plates
give serial numbers that are necessary when communicating with Dresser-Rand about the
equipment.
Also, do not remove safety labels. If these labels are removed or defaced, new ones should be
obtained from Dresser-Rand Company. Refer all communications to the nearest Dresser-
Rand Authorized Packager or the Dresser-Rand Gas Field Compressor Group.
ii
PG-4875-C (HOSS) Front Matter
SAFETY PRECAUTIONS
Safety Information
WARNING
DO NOT OPERATE THIS EQUIPMENT IN EXCESS OF ITS
RATED CAPACITY, SPEED, PRESSURE AND TEMPERATURE, NOR
OTHERWISE THAN IN ACCORDANCE WITH THE INSTRUCTIONS
CONTAINED IN THIS SERVICE MANUAL. OPERATION OF THE
EQUIPMENT IN EXCESS OF THE CONDITIONS SET FORTH IN THE
SALES CONTRACT WILL SUBJECT IT TO STRESSES AND STRAINS
WHICH IT WAS NOT DESIGNED TO WITHSTAND. FAILURE TO
HEED THIS WARNING MAY RESULT IN AN ACCIDENT CAUSING
PERSONAL INJURY OR PROPERTY DAMAGE.
WARNING
READ CAREFULLY AND UNDERSTAND THIS SERVICE MANUAL BEFORE
INSTALLING OR OPERATING THE COMPRESSOR.
This service manual contains important instructions and information on the installation,
operation and servicing of Dresser-Rand HOSS Model compressors. THE
IMPORTANCE OF GETTING THIS SERVICE MANUAL INTO THE HANDS OF THE
PERSON IN CHARGE OF INSTALLING THE COMPRESSOR CANNOT BE
OVEREMPHASIZED. All personnel involved in the installation, operation and servicing
of the compressor should have access to this service manual and be familiar with its
contents. Strict adherence to these instructions will be repaid by satisfactory compressor
performance and acceptable upkeep costs.
Do not remove the stainless steel nameplates that are attached to the machine. These
plates give serial numbers that are necessary when communicating with Dresser-Rand
about the equipment. Also, do not remove safety labels. If these labels are removed or
defaced, new ones should be obtained from Dresser-Rand Company.
REFER ALL COMMUNICATIONS TO THE NEAREST DRESSER-RAND COMPANY

OFFICE.
iii
Dangers, warnings and cautions appearing throughout this service manual are of
paramount importance to personnel and equipment safety. Prior to any attempt to operate,
maintain, troubleshoot, or repair any part of the compressor, all DANGERS, WARNINGS and
CAUTIONS should be thoroughly reviewed and understood. Refer to the Safety Summary that
starts on the next page. The information immediately following defines "signal words" as they
are used in this manual.
SIGNAL WORDS ARE USED TO IDENTIFY LEVELS OF HAZARD SERIOUSNESS. THEIR

SELECTION IS BASED ON THE LIKELY CONSEQUENCE OF HUMAN INTERACTION WITH
THE HAZARD IN TERMS OF:
● DEGREE OF SEVERITY (minor injury, severe injury, death)
● THE PROBABILITY OF SEVERITY (will result, could result)
DANGER
The word DANGER signifies immediate hazards that WILL result in severe
personal injury or death. In the service manual, this should be construed
to be a VERY STRONG Warning (see below).
WARNING
The word WARNING refers to hazards or unsafe practices that COULD
result in severe personal injury or death. This is found quite often in the
service manual due to its association with unsafe practices.
CAUTION
The word CAUTION refers to hazards or unsafe practices that COULD
result in minor personal injury, or product or property damage. This word
is found frequently in the service manual due to the fact that bad
maintenance practices or procedures can so often result in damage to the
compressor. Because what constitutes a "minor" injury is open to debate,
we have upgraded many CAUTIONS to WARNING.
NOTE
NOTES are used to highlight certain operating or maintenance conditions or

statements that are essential but not of a known hazardous nature, as would be
indicated by DANGER, WARNING or CAUTION.
iv
v
SAFETY SUMMARY
The following safety precautions are being recommended only in regard to the
compressor and other Dresser-Rand supplied equipment (ex: motors, consoles, etc.). Abide by
all OSHA and all other applicable safety regulations, including all site-specific safety and work
procedures.
The installation, operation and maintenance of a compressor and auxiliary components

may present certain hazards that are unique to this type of equipment. The following list of
safety precautions must be thoroughly read and reviewed by all personnel prior to working with
or on the compressor equipment and systems. These general statements are expanded upon
in the sections of the manual appropriate to their application. Failure to heed these
statements can result in an incident causing property damage, personal injury or death.
● All electrical motor and control wiring must be carefully installed in accordance with the
National Electric Code, the Occupational Safety and Health Act of 1970 (OSHA) and
any other code requirements at the installation site.
● Piping subject to temperatures in excess of 175ºF (80ºC) which may be touched by

personnel must be suitably guarded or insulated.
● It is imperative that all gases lighter or heavier than air, active or inactive, toxic,
combustible, obnoxious, objectionable, or in any way harmful to personnel or
equipment, be piped away from the compressor. There must be no manifolding of vent
tubing or piping; nor can back pressure be allowed to develop in any vent line. Gases
may be re-circulated as required by the process, but in any case must be controlled
and/or disposed of in accordance with OSHA regulations and local pollution laws.
● The compressor must be fitted with pressure relief valves or rupture disks to limit the
discharge pressures to a safe maximum. NEVER install an intervening valve between a
compressor cylinder and the pressure relief valve or rupture disk.
● Pressure relief valves must have their settings tested at least once a year, and more
often under extreme operating conditions, using an appropriate bench test.
● If a pressure relief valve or rupture disk blows during operation, stop the unit
immediately and determine the cause.
● Pressure relieving devices that are vented to the atmosphere must have their outlet
connections directed away from operator stations.
 Compressor manufacturers utilize elastomer seals (O-rings) found in today’s

compressor frames, distance pieces, compressor cylinders and valves. When selecting
O-rings the process conditions must be thoroughly understood. At high pressure, high
mole weight and even some lower mole weight gas applications, gases can diffuse into
the O-ring. Upon rapid blowdown or decompression, the impregnated gas may exit too
quickly causing the O-ring to “blister”, thus leading to process gas leakage upon re-start.
For high-pressure, high mole weight and even some lower mole weight gas
applications, O-ring material selection, O-ring hardness (durometer generally 85 – 90)
and decreased blowdown rate (psi / min.) have alleviated problems with leakage due to
“blistering”. Dresser-Rand Co. can provide guidance for O-ring or seal selection to
reduce the possibility of O-ring leakage due to “blistering”.
v
● Rotating equipment must not be placed in operation unless adequate safeguards have
been provided to protect operating personnel.
● Service on a machine shall always start with cleaning the floor and the outside of the
machinery to remove oil that could cause maintenance personnel to slip.
● Whenever a compressor is shut down for repairs, positive steps must be taken to
prevent the prime mover from being inadvertently energized and started. Equipment
being worked on should be “Locked Out” and “Tagged Out” to ensure against
inadvertently providing power and accidentally starting. In addition, a warning sign
bearing the legend "WORK IN PROGRESS-DO NOT START", or similar wording, shall
be attached to the starting equipment.
● Whenever the compressor is shut down because overheating is suspected, a minimum

period of 30 minutes must elapse before the crankcase is opened. Premature opening
of the crankcase can result in a crankcase explosion.
● Prior to opening the compressor, or undertaking a major overhaul, the unit must be
positively blocked against rollover and movement of the running gear. When the unit is
equipped with a flywheel-locking device, this device must be used to prevent rollover.
Blocking of the crankshaft or crossheads is an alternate method of preventing accidental
rollover.
● Never open a compressor cylinder or any other part of the compression system without
first completely relieving all pressure within the compressor cylinders, piping, vessels
and coolers; and taking all necessary precautions to prevent accidental pressurizing of
the system.
● Compressors handling toxic or flammable gases must be isolated from the process
piping by means of blinds, or double valves and bleeders, when major maintenance is
required. Before opening such compressors, the equipment MUST be purged or
evacuated.
● Incorrect placement of the inlet and discharge valves in the cylinders can cause an
extremely hazardous condition. INSTALLING AN INLET VALVE IN A DISCHARGE
VALVE PORT, OR INSTALLING A DISCHARGE VALVE UPSIDE DOWN MAY CAUSE
EXCESSIVE PRESSURE IN THE CYLINDER RESULTING IN RUPTURE AND/OR AN
EXPLOSION.
● Discharge valve ports usually are made slightly smaller at the minor diameter below the
valve gasket seat; this is called "polarization". When an inlet valve is installed in a
discharge port by mistake, it will not fit down into the port properly and the mechanic will
be alerted to the error.
● In many cases, the inlet valve stop plates have lugs that will prevent an inlet valve from
being installed in a discharge valve port by mistake; this is another type of "polarization".
The minor diameter of the discharge port is slightly smaller so the inlet valve will not fit
properly, alerting the mechanic to the error.
● If IN DOUBT as to whether a valve is inlet or discharge, or as to which cylinder valve

ports receive inlet or discharge valves, CHECK WITH YOUR SUPERVISOR.
vi v
● Corrective action must be taken when the piston rod pressure packing vent gas leakage
is excessive, or when there is a sudden increase in the leakage rate.
● After any maintenance or overhaul of the compressor, the unit must be barred through
at least one complete revolution to ensure that there are no mechanical obstructions
within the machine.
● A manual bar and fulcrum and/or a hydraulic or pneumatic barring rig may have been
provided as a means of rotating the compressor crankshaft during installation, during
maintenance, prior to start-up after maintenance or overhaul, and at any other time
exact positioning of the running gear is required. Compressor cylinders must be
depressurized to atmospheric pressure before barring. Compressor pistons will move to
crank end dead center as an equilibrium condition due to the difference in crank end
and head end piston surface areas if exposed to the process gas pressure. Failure to
depressurize the compressor cylinders prior to barring may result in unexpected rotation
that can cause personal injury.
● Established operating and maintenance procedures, as well as basic safety precautions

must be reviewed with the operating and maintenance personnel at regular intervals, not
to exceed six months. Newly assigned operators must be thoroughly trained in the safe
operation of this equipment before they are permitted to operate it.
● Whenever an outer head is removed from the compressor cylinder, make certain that
the piston vent hole(s), if used, located in the outer face of the piston are open and that
the piston does not contain pressure. If the compressor has been handling a flammable
or toxic gas, appropriate precautions shall be taken before clearing a vent hole that has
become plugged.
● Never use an air impact wrench for ANY tightening of critical fasteners. An impact
wrench cannot accurately impart the proper bolt or stud pre-stress. See CHAPTER 5,
GENERAL DATA AND SPECIFICATIONS of this Instruction Manual for detailed
fastener tightening requirements and procedures.
● Special attention should be paid to all detailed DANGER, WARNING and CAUTION
statements located throughout this manual, and to all SAFETY LABELS affixed to the
equipment.
vii
WARRANTY, REMEDY, DISCLAIMER
A. Dresser-Rand warrants that the equipment manufactured and delivered by Dresser-

Rand under the terms of this Agreement will be free from defects in material and
workmanship until the earliest to occur of the following events:
1. One year after startup.

2. Eighteen (18) months after shipment by packager.
3. Twenty-four (24) months after shipment by Dresser-Rand to Packager.
The Packager shall be obligated to promptly report any claimed defects in writing to
Dresser-Rand immediately upon discovery and, in any event, within the above period.
After notice from Packager and substantiation of the claim, Dresser-Rand shall, at its
option, correct such defect either by suitable repair to such equipment or part, or by
furnishing replacement equipment or part(s), as necessary, to the original ex-works
point of shipment.
B. DRESSER-RAND MAKES NO OTHER WARRANTY OR REPRESENTATION OF ANY

KIND. ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE ARE HEREBY DISCLAIMED.
C. With respect to equipment, parts and work not manufactured or performed by Dresser-
Rand, Dresser-Rand's only obligation shall be to assign to Packager whatever warranty
Dresser-Rand receives from the manufacturer.
D. Dresser-Rand shall not be liable for the cost of any repair, replacement, or adjustment to
the equipment or parts made by the Packager or for labor performed by the Packager or
others, without Dresser-Rand's prior written approval.
E. No equipment or part furnished by Dresser-Rand shall be deemed to be defective by

reason of normal wear and tear, failure to resist erosive or corrosive action of any fluid
or gas, or of Packagers's failure to properly store, install, operate or maintain the
equipment in accordance with good industry practices or specific recommendations of
Dresser-Rand.
F. The Packager shall not operate equipment which is considered to be defective without
first notifying Dresser-Rand in writing of its intention to do. Any such use of the
equipment will be at the Packager's sole risk and expense.
G. The repair or replacement of the equipment, spare or replacement part(s) by Dresser-

Rand under this Warranty schedule shall constitute Dresser-Rand's sole obligation and
Packager's sole and exclusive remedy for all claims of defects regarding the equipment
and parts furnished hereunder.
H. The compressor owner should contact an authorized Dresser-Rand Packager for all
required warranty or non-warranty service.
viii
LIMITATIONS OF LIABILITY
A. The remedies of the Packager set forth herein are exclusive and the total liability of
Dresser-Rand with respect to claims under this Agreement or regarding the equipment,
spare or replacement parts and services incidental thereto as furnished hereunder,
whether based in contract, tort (including negligence and strict liability) or otherwise,
shall not exceed the purchase price of the services or the unit of equipment or part(s)
upon which such liability is based.
B. Dresser-Rand shall in no event be liable for any consequential, incidental, indirect,

special or punitive damages arising out of this Agreement or any breach thereof, or any
defect in, or failure of, or malfunction of the equipment or part(s) hereunder, including
but not limited to claims based on loss of use, lost profits or revenue, interest, lost
goodwill, work stoppage, impairment of other goods, loss by reason of shutdown or non-
operation, increased expenses of operation, cost of purchase of replacement power or
claims of Packager or customers of Packager for service interruption whether or not
such loss or damage is based on contract, tort (including negligence and strict liability)
or otherwise.
COMMENTS OF INTEREST TO OUR CUSTOMERS
General
Service Manuals are furnished for every Dresser-Rand Compressor. If additional details
of your job are required, we will be happy to furnish this information.
This manual is intended to cover many of the special points of operating and
maintenance of the compressor components, and to supplement the experience and
mechanical ability of a competent engineer.
Dresser-Rand service is available to every compressor owner. We have a continued

interest in the welfare of our machinery. We wish to build and stand by every unit so that the
purchase of this compressor will always be considered a wise investment.
Consultation
Our engineering department welcomes inquiries regarding any phase of compressor

practice, operation and repairs or changes to meet unexpected conditions. Our sales
department and branch representatives will confer with you on any prospective installation or
change. Call, write or wire our branch offices for information and advice on any point.
Inspection
These compressors will operate satisfactorily for years with little special attention. A
preventative maintenance schedule will do much to ensure optimum performance of the unit,
while avoiding possible difficulties at some inconvenient time.
ix
Renewal Parts
If you will write us fully about your trouble or unusual wear, we may be able to make
helpful suggestions that will correct your problem. We keep standard parts on hand for
replacement when required.
Service
Dresser-Rand distributors maintain a force of highly trained Field Service

Representatives, skilled in compressor work, who are available for installation, inspection or
repair. They can be secured on reasonable notice. Contact your nearest Dresser-Rand
distributor for service information.
Proper erection and starting of the compressor is extremely important. The success of a
unit frequently depends on how it is installed. We strongly urge that such work be supervised
by skilled Field Service Representatives, who are thoroughly familiar with construction, and who
can also instruct the operators in the care and handling of the equipment.
Many customers, especially those operating several units, have Field Service
Representatives make periodic inspections to prevent malfunctions and to ensure the best
possible operating results. These representatives can explain how to operate D-R units to
achieve the greatest possible operating results with the greatest efficiency and economy, while
obtaining the longest possible equipment life.
x x
Form PG-4875-C
DRESSER-RAND TABLE OF CONTENTS
HOSS
CHAPTER 1 – INTRODUCTION
Paragraph Page
1-1. GENERAL INFORMATION ......................................................................... 1-2

1-1.1. Ratings and Performance Characteristics ............................................. 1-2
1-2. SERIAL NUMBERS ..................................................................................... 1-2
1-3. CYLINDER NAMEPLATE INFORMATION ................................................. 1-3
1-3.1. Cylinder Type, Serial Number, Bore and Stroke ................................... 1-3
1-3.2. Rated Discharge Pressure .................................................................... 1-4
1-3.3. Maximum Allowable Working Pressure ................................................. 1-4
1-3.4. Hydrostatic Test Pressure ..................................................................... 1-4
1-3.5. Maximum Cooling Water Pressure ........................................................ 1-4
1-3.6. Maximum Allowable Discharge Gas Temperature ................................ 1-4
1-3.7. Maximum Speed.................................................................................... 1-4
1-3.8. Base Cylinder Clearance ....................................................................... 1-4
1-3.9. Normal Lineal Clearance ....................................................................... 1-5
1-3.10. Added Fixed Clearance ......................................................................... 1-5
CHAPTER 2 – LUBRICATION
Paragraph Page

2-2. FRAME AND RUNNING GEAR LUBRICATION SYSTEM.......................... 2-2
2-2.1. Main Oil Pump ....................................................................................... 2-3
A. Main Oil Pump Removal and Disassembly ................................. 2-4
B. Main Oil Pump Assembly and Installation ................................... 2-6
2-2.2. Oil Pressure Regulation Valve............................................................... 2-8
2-2.3. Hand Oil Priming Pump ......................................................................... 2-10
A. Hand Oil Priming Pump Removal and Disassembly ................... 2-11
B. Hand Oil Priming Pump Assembly and Installation ..................... 2-11
2-2.4. Oil Pressure Gauges ............................................................................. 2-12
2-2.5. Low Oil Pressure Shutdown Protection ................................................. 2-12
2-2.6. Oil Cooler (Heat Exchanger) ................................................................. 2-13
2-2.7. Oil Filter ................................................................................................. 2-13
2-2.8. Frame Oil Recommendations ................................................................ 2-15
A. General Requirements ................................................................ 2-15
Table 2-1. Crankcase Oil Viscosity Requirements .................... 2-16
B. Viscosity Requirements ............................................................... 2-16
C. Inspection .................................................................................... 2-17
D. Oil Change Schedule .................................................................. 2-17
2-2.9. Frame Oil Level ..................................................................................... 2-17
2-2.10. Frame Breather ..................................................................................... 2-17
i
Table of Contents PG-4875-C (HOSS)
CHAPTER 2 – LUBRICATION (continued)

Paragraph Page
2-3. CYLINDER LUBRICATION SYSTEM ............................................................... 2-18

2-3.1. Block-type Lubrication System .................................................................... 2-18
Table 2-2. Oil Output per Cycle ....................................................... 2-20
A. Filling and Purging the System ......................................................... 2-21
B. Maintenance and Troubleshooting .................................................... 2-22
2-3.2. Pump-to-Point Lubrication System .............................................................. 2-24
A. Lubricator Operation ......................................................................... 2-25
B. Filling and Priming the System.......................................................... 2-25
C. Lubricator Adjustment ....................................................................... 2-26
2-3.3. Cylinder Oil Recommendations ................................................................... 2-26
Table 2-3. Break-in Oil Feed Drops per Minute (dpm) to Cylinder .. 2-27
A. General Requirements ...................................................................... 2-28
Table 2-4. Standard Cylinder Oil Requirements .............................. 2-28
B. Service Considerations ..................................................................... 2-29
C. Inspection.......................................................................................... 2-29
D. Synthetic Lubricants.......................................................................... 2-29
2-3.4. Break-in and Operation ............................................................................... 2-30
2-3.5. Extended Shutdown .................................................................................... 2-32
2-3.6. System Malfunctions and Their Causes ...................................................... 2-32
CHAPTER 3 – OPERATION AND TROUBLESHOOTING

Paragraph Page
3-1. GENERAL INFORMATION ............................................................................... 3-2

3-2. PREPARATION FOR INITIAL START .............................................................. 3-2
3-2.1. Alignment Check ......................................................................................... 3-2
3-2.2. Lubrication Systems .................................................................................... 3-4
3-2.3. Compressor Cylinders ................................................................................. 3-5
3-2.4. General Inspections and Adjustments......................................................... 3-6
3-2.5. Compressor Cooling System ....................................................................... 3-6
3-3. CAPACITY CONTROL ...................................................................................... 3-6
3-3.1. Cylinder Clearance Volume ......................................................................... 3-7
3-3.2. Cylinder Unloading ...................................................................................... 3-7
3-3.3. Suction Pressure Control ............................................................................ 3-7
3-3.4. Capacity Control Bypass ............................................................................. 3-7
3-4. COMPRESSOR LOADING AND UNLOADING ................................................ 3-8
3-4.1. Loading/Unloading Procedure – Bypass and Discharge Valve Method ...... 3-9
3-4.2. Loading/Unloading Procedure – Vent Valve Method .................................. 3-10
3-5. INITIAL START-UP ........................................................................................... 3-10
3-6. BREAK-IN AND OPERATION ........................................................................... 3-12
3-7. SUGGESTED ROUTINE STARTING PRACTICES .......................................... 3-13
3-8. ROUTINE STOPPING....................................................................................... 3-15
3-9. EMERGENCY OR NON-SCHEDULED SHUTDOWN ...................................... 3-16
3-10. SHUTDOWN FOR AN EXTENDED PERIOD ................................................... 3-17
ii
PG-4875-C (HOSS) Table of Contents
CHAPTER 3 – OPERATION AND TROUBLESHOOTING (continued)

Paragraph Page
3-11. ROUTINE OPERATION AND MAINTENANCE .......................................... 3-17

3-11.1. Daily....................................................................................................... 3-18
3-11.2. Weekly ................................................................................................... 3-19
3-11.3. Monthly .................................................................................................. 3-19
3-11.4. Every Three Months .............................................................................. 3-20
3-11.5. Every Six Months................................................................................... 3-20
3-11.6. Annually ................................................................................................. 3-20
3-12. TROUBLESHOOTING BY SYMPTOM ....................................................... 3-22
Table 3-1. Compressor Troubleshooting Chart. ........................ 3-22
Table 3-2. Valve Troubleshooting Chart .................................... 3-27
CHAPTER 4 – MAINTENANCE
Paragraph Page

4-2. SAFETY PRECAUTIONS............................................................................ 4-4
4-3. ACCESSORY EQUIPMENT........................................................................ 4-5
4-4. FRAME ........................................................................................................ 4-5
4-5. MAIN BEARINGS ........................................................................................ 4-7
4-5.1. Checking Main Bearing Clearance ........................................................ 4-8
4-5.2. Replacing a Main Bearing ..................................................................... 4-8
4-5.3. Bearing Crush........................................................................................ 4-10
4-6. CRANKSHAFT ............................................................................................ 4-10
4-6.1. Checking Crankshaft Thrust .................................................................. 4-11
4-7. CRANKSHAFT OIL SEAL ........................................................................... 4-12
4-8. CONNECTING RODS ................................................................................. 4-13
4-8.1. Checking Connecting Rod Bearing Clearance ...................................... 4-14
4-8.2. Replacing a Connecting Rod Bearing ................................................... 4-15
4-8.3. Replacing a Small End Bushing ............................................................ 4-17
4-8.4. Removing the Connecting Rod.............................................................. 4-18
4-8.5. Installing the Connecting Rod................................................................ 4-20
4-8.6. Connecting Rod Bolt Stretch Micrometer Procedure............................. 4-21
4-9. CROSSHEADS ........................................................................................... 4-23
4-9.1. Removing the Crosshead ...................................................................... 4-24
4-9.2. Installing the Crosshead ........................................................................ 4-26
4-10. CROSSHEAD SHOES ................................................................................ 4-28
4-10.1. Crosshead Shoe Replacement.............................................................. 4-28
4-10.2. Piston Rod Runout Adjustment ............................................................. 4-31
Table 4-1. Normal Cold Vertical Piston Rod Runout ................. 4-32
4-11. COMPRESSOR CYLINDERS ..................................................................... 4-34
4-11.1. Removing the Compressor Cylinder ..................................................... 4-36
4-11.2. Installing the Compressor Cylinder........................................................ 4-37
iii
Table of Contents PG-4875-C (HOSS)
CHAPTER 4 – MAINTENANCE (continued)

Paragraph Page
4-12. PISTON AND PISTON RODS ........................................................................... 4-39

4-12.1. Removing the Piston Rod ............................................................................ 4-39
4-12.2. Piston and Rod Disassembly – Cast/Nodular Iron Pistons ......................... 4-41
4-12.3. Piston and Rod Assembly – Cast/Nodular Iron Pistons .............................. 4-43
4-12.4. Piston and Rod Disassembly – Aluminum Pistons ...................................... 4-45
4-12.5. Piston and Rod Assembly – Aluminum Pistons .......................................... 4-45
Graph 4-1. Piston Nut Tightening Angle ........................................... 4-47
4-13. INSTALLING the PISTON ROD and ADJUSTING END CLEARANCE ............ 4-49
4-14. INSPECTION / MAINTENANCE of CYLINDER BORES.................................. 4-51
Table 4-2. Cylinder Reconditioning Data .......................................... 4-52
4-14.1 Honing ......................................................................................................... 4-53
4-15. NON-METALLIC COMBINATION PISTON & RIDER RINGS ........................... 4-53
4-15.1. Handling Instructions ................................................................................... 4-53
4-15.2. Establishing Ring Wear Rate ...................................................................... 4-54
4-15.3. Replacing Rings .......................................................................................... 4-55
4-15.4. Installing Rings ............................................................................................ 4-55
Table 4-3. Piston and Ring Clearance for Standard Cylinders ......... 4-56
4-15.5. Breaking-in Combination Rings ................................................................... 4-58
4-16. PISTON ROD PRESSURE PACKING .............................................................. 4-58
4-16.1. Packing Rings ............................................................................................. 4-59
Table 4-4. Packing Clearances ........................................................ 4-62
4-16.2. Packing Gasket ........................................................................................... 4-62
4-16.3. Packing Cases ............................................................................................ 4-62
4-16.4. Installing the Packing .................................................................................. 4-62
4-16.5. Packing Operation and Maintenance .......................................................... 4-65
4-16.6. Inspecting the Packing ................................................................................ 4-65
4-16.7. Replacing the Packing................................................................................. 4-65
4-17. PISTON ROD OIL SCRAPER RINGS .............................................................. 4-66
4-18. BALANCE CYLINDER (If Used)........................................................................ 4-68
4-19. COMPRESSOR VALVES ................................................................................. 4-69
4-19.1. Description of Operation.............................................................................. 4-70
4-19.2. Valve Maintenance Recommendations ....................................................... 4-70
4-19.3. Removing the Valves – O-Ring Valve Cover............................................... 4-72
4-19.4. Disassembling and Servicing the Valve ...................................................... 4-75
4-19.5. Reconditioning the Valve Seat .................................................................... 4-77
4-19.6. Reconditioning the Stopplate ...................................................................... 4-78
4-19.7. Assembling the Valve .................................................................................. 4-79
4-19.8. Installing the Valves – O-Ring Valve Cover ................................................ 4-80
iv
v
PG-4875-C (HOSS) Table of Contents
CHAPTER 4 – MAINTENANCE (continued)

Paragraph Page
4-20. REGULATION DEVICES ............................................................................ 4-83

4-20.1. Inlet Valve Unloaders ............................................................................ 4-83
A. Control and Vent Piping Considerations ..................................... 4-88
B. Unloader Cleanliness .................................................................. 4-89
C. Removing the Operator, Unloader and Valve Assembly............. 4-90
D. Disassembling the Operator – Air-to-Load (Direct-Acting) .......... 4-91
E. Disassembling the Operator – Air-to-Unload (Reverse-Acting)... 4-92
F. Disassembling the Indicator ........................................................ 4-92
G. Disassembling the Unloader Guide ............................................ 4-93
H. Servicing the Packing Gland ....................................................... 4-94
I. Reassembling the Unloader Guide .............................................. 4-95
J. Reassembling the Indicator ......................................................... 4-95
K. Reassembling the Operator – Air-to-Load (Direct-Acting)........... 4-96
L. Reassembling the Operator – Air-to-Unload (Reverse-Acting).... 4-96
M. Installing the Operator – Air-to-Load (Direct-Acting) .................. 4-97
N. Installing the Operator – Air-to-Unload (Reverse-Acting)............ 4-98
4-20.2. Variable Volume Clearance Pockets ..................................................... 4-99
Table 4-5. Maximum Allowable Clearance Volume ................... 4-103
A. Removal/Disassembly of the One-Piece Style Outer Head ....... 4-103
B. Assembly/Installation of the One-Piece Style Outer Head ........ 4-105
C. Removal/Disassembly of the Two-Piece Style Outer Head ....... 4-106
D. Assembly/Installation of the Two-Piece Style Outer Head ........ 4-108
E. Removal/Disassembly of the Plug Type VVCP ......................... 4-109
F. Assembly/Installation of the Plug Type VVCP ........................... 4-110
CHAPTER 5 – GENERAL SPECIFICATIONS AND DATA

Paragraph Page
5-1. GENERAL AND OPERATING DATA .......................................................... 5-2

Table 5-1. HOSS Compressor General Data ............................ 5-2
5-2. ASSEMBLY FITS AND CLEARANCES ...................................................... 5-4
Table 5-2. Running Gear Fits and Tolerances (Inches) ............ 5-4
Table 5-2A. Running Gear Fits and Tolerances (Metric) ........... 5-5
5-3. TIGHTENING REQUIREMENTS ................................................................ 5-6
5-3.1. Preparation of Thread and Seating Surfaces ........................................ 5-6
5-3.2 Recommended Tightening Sequence / Procedure................................ 5-6
5-3.3. Closely Observe the Following .............................................................. 5-6
5-3.4. Checking Fastener Tightness ................................................................ 5-7
A. When to Check Fastener Tightness .................................................. 5-7
B. How to Check Fastener Tightness .................................................... 5-8
5-3.5. Fastener Pre-Stress .............................................................................. 5-8
5-3.6. Compressor Cylinder Bolting ................................................................. 5-9
Table 5-3. Pre-Stress Levels for HOSS..................................... 5-9
5-3.7. Standard Torque Values........................................................................ 5-10
Table 5-4. Torque Values Based on Common Mineral Oil ........ 5-10
5-3.8. Frame and Running Gear Bolting .......................................................... 5-11
Table 5-5. HOSS Torque Wrench Values ................................. 5-11
v
Form PG-4875-C
DRESSER-RAND INTRODUCTION
HOSS
CHAPTER 1
Paragraph Page

1-1.1. Ratings and Performance Characteristics ................................................... 1-2
1-2. SERIAL NUMBERS........................................................................................... 1-2
1-3. CYLINDER NAMEPLATE INFORMATION ....................................................... 1-3
1-3.1. Cylinder Type, Serial Number, Bore and Stroke ......................................... 1-3
1-3.2. Rated Discharge Pressure .......................................................................... 1-4
1-3.3. Maximum Allowable Working Pressure ....................................................... 1-4
1-3.4. Hydrostatic Test Pressure ........................................................................... 1-4
1-3.5. Maximum Cooling Water Pressure .............................................................. 1-4
1-3.6. Maximum Allowable Discharge Gas Temperature ...................................... 1-4
1-3.7. Maximum Speed ......................................................................................... 1-4
1-3.8. Base Cylinder Clearance ............................................................................. 1-4
1-3.9. Lineal Clearance ......................................................................................... 1-5
1-3.10. Added Fixed Clearance ............................................................................... 1-5
1-1
Introduction PG-4875-B (HOSS)
1-1. GENERAL INFORMATION
The HOSS is the next logical step in the evolution of the HOS compressor. Based on the
proven history of the HOS for over 26 years, along with years of Dresser-Rand proven dedicated
compressor development, the HOSS was created to supply more of what you like about this style
of compressor.
1-1.1. Ratings and Performance Characteristics
Maximum Allowable Operating Rod load: 75,000 lbs (34,000 kg) compression and tension
Maximum Allowable Gas Load (Flange): 87,000 lbs (39,500 kg)
Stroke: 6.00” (152.4 mm) 7.00” (177.8 mm)
Maximum Speed: 1200 PRM 1000 RPM
Minimum Loaded Speed: 500 RPM 500 RPM
Maximum BHP/Throw 2 & 4 THROW: 1550 HP (1150 kW) 1400 HP (1040 kW)
6 THROW: 1450 HP (1080 kW) 1300 HP ( 970 kW)
Piston Rod Diameter: 2.875 in. (73.0 mm) 2.875 in. (73.0 mm)
Standard Cylinder Sizes Available: 4.75 in – 26.50 in 4.75 in – 26.50 in

(120.7 mm – 673.1 mm) (120.7 mm – 673.1 mm)
Maximum Cylinder Working Pressures: 2750 – 280 psig 2750 – 280 psig
(18,960 kPa – 1930 kPa) (18,960 kPa – 1930 kPa)
Billet Cylinders Available: 3.75 in – 6.50 in Up to 8800 psig MAWP

(95.3 mm – 165.1 mm) (60,700 kPa MAWP)
Direction of Rotation: Counter-clockwise viewing at pump end
1-2. SERIAL NUMBERS
Correspondence concerning your compressor and related equipment must include the
serial numbers of the equipment about which you are inquiring. A complete record of serial
numbers and other data on your Dresser-Rand compressor is kept on file at the factory. Giving
the serial numbers in your correspondence and parts orders helps us in providing prompt
service.
1. The compressor frame serial number applies to the frame and running gear
parts. It is located on a nameplate that is attached to the side of the frame at the
oil pump end. The serial number is also permanently stamped directly below the
nameplate in the frame metal. It consists of several letters and numbers.
Always give the complete serial number (for example: 6SHF100) when
requesting specific information about the frame.
1-2
PG-4875-B (HOSS) Introduction
2. Each compressor cylinder has its own serial number that is stamped on a
nameplate attached to the cylinder. The cylinder nameplate also includes other
data that is described in the section that follows. Always give the complete
serial number (for example: 7SHC100) when requesting specific information
about the cylinder.
1-3. CYLINDER NAMEPLATE INFORMATION
The nameplate attached to the compressor cylinder (See Figure 1-1) contains
information that allows both the customer and Dresser-Rand to identify a particular cylinder.
The following is an explanation of some of the terms used on the nameplate.
TP-4609C
Figure 1-1. Cylinder Nameplate
1-3.1. Cylinder Type, Serial Number, Bore and Stroke
The first block describes the compressor type. Following this is the block for the
serial number. The cylinder serial number is the most important item stamped on the
nameplate. It allows the customer, the distributor and the manufacturer to identify a
particular cylinder, its specifications, the parts used to build it and the performance
conditions for which it was designed. This is important in that it allows tracking of a
particular cylinder throughout its history, no matter what frame it may be installed on in
later years. Always give this serial number when ordering spare parts. This will
expedite the handling of your order and helps prevent shipment of incorrect parts.
The cylinder bore is the inside diameter of the cylinder. If there is a liner present,
the cylinder bore is the inside diameter of the liner. This is also the nominal piston
diameter. Liners of different thicknesses may be installed in a given cylinder to vary the
bore diameter. The stroke is the distance the piston and rod travels (forward or
backwards) for every 1/2 revolution of the crank.
1-3
Introduction PG-4875-B (HOSS)
1-3.2. Rated Discharge Pressure
The rated discharge pressure, or RDP, is the maximum pressure the cylinder is
allowed to see under normal continuous operating conditions.
1-3.3. Maximum Allowable Working Pressure
The maximum allowable working pressure, or MAWP, is the maximum gas

pressure permitted in the cylinder period. The cylinder may be operated for short
periods of time at pressures up to this figure provided that other factors (such as driver
horsepower, maximum bearing loads, and piping and vessel limitations) do not prohibit
this. Safety valve settings are usually much lower than this figure, and may never
exceed it in any case.
1-3.4. Hydrostatic Test Pressure
The pressure at which the cylinder has been hydrotested. Hydrostatic tests are
always performed at pressures at least 1.5 times that of the MAWP.
1-3.5. Maximum Cooling Water Pressure
This pressure limitation applies not only to water-jacketed cylinders, but also to
internally water-cooled packing cases as well.
1-3.6. Maximum Allowable Discharge Gas Temperature
This is the highest temperature to which any part of the compressor cylinder
should be exposed.
1-3.7. Maximum Speed
This is the maximum design speed of the cylinder. Certain cylinders, mainly the
large ones with high reciprocating weights, may have speed limits that are lower than
that of the frame. This is uncommon and is always addressed in the early states of any
potential application.
1-3.8. Base Cylinder Clearance
This is the inherent clearance that lies within and/or built within the cylinder. It is
in the form of a percent of the swept volume for each given end of the cylinder. It
cannot be changed without physically altering the internals of the cylinder.
1-4
PG-4875-B (HOSS) Introduction
1-3.9. Lineal Clearance
The clearance between the piston and the head when the piston is at the end of
the stroke (for each end). It is required to allow for the thermal expansion of the piston
and rod when temperatures increase through compression.
1-3.10. Added Fixed Clearance
The clearance added by some physical means to meet the required operating
condition(s). It is typically added in the form of valve spacers or a shorter than normal
head or piston.
1-5
Form PG-4875-C
DRESSER-RAND LUBRICATION
HOSS
CHAPTER 2
Paragraph Page

2-2. FRAME AND RUNNING GEAR LUBRICATION SYSTEM ............................... 2-2
2-2.1. Main Oil Pump ............................................................................................. 2-3
A. Main Oil Pump Removal and Disassembly ....................................... 2-4
B. Main Oil Pump Assembly and Installation ......................................... 2-6
2-2.2. Oil Pressure Regulation Valve .................................................................... 2-8
2-2.3. Hand Oil Priming Pump ............................................................................... 2-10
A. Hand Oil Priming Pump Removal and Disassembly ......................... 2-11
B. Hand Oil Priming Pump Assembly and Installation ........................... 2-11
2-2.4. Oil Pressure Gauges ................................................................................... 2-12
2-2.5. Low Oil Pressure Shutdown Protection ....................................................... 2-12
2-2.6. Oil Cooler (Heat Exchanger) ....................................................................... 2-13
2-2.7. Oil Filter ....................................................................................................... 2-13
2-2.8. Frame Oil Recommendations ...................................................................... 2-15
Table 2-1. Crankcase Oil Viscosity Requirements ......................... 2-16
B. Viscosity Requirements..................................................................... 2-16
C. Inspection.......................................................................................... 2-17
D. Oil Change Schedule ........................................................................ 2-17
2-2.9. Frame Oil Level ........................................................................................... 2-17
2-2.10. Frame Breather ........................................................................................... 2-17
2-3. CYLINDER LUBRICATION SYSTEM ............................................................... 2-18
2-3.1. Block-type Lubrication System .................................................................... 2-18
Table 2-2. Oil Output per Cycle ...................................................... 2-20
A. Filling and Purging the System ......................................................... 2-21
B. Maintenance and Troubleshooting .................................................... 2-22
2-3.2. Pump-to-Point Lubrication System .............................................................. 2-24
A. Lubricator Operation ......................................................................... 2-25
B. Filling and Priming the System.......................................................... 2-25
C. Lubricator Adjustment ....................................................................... 2-26
2-3.3. Cylinder Oil Recommendations ................................................................... 2-26
Table 2-3. Break-in Oil Feed Drops per Minute (dpm) to Cylinder . 2-27
Table 2-4. Standard Cylinder Oil Requirements ............................. 2-28
B. Service Considerations ..................................................................... 2-29
C. Inspection.......................................................................................... 2-29
D. Synthetic Lubricants.......................................................................... 2-29
2-3.4. Break-in and Operation ............................................................................... 2-30
2-3.5. Extended Shutdown .................................................................................... 2-32
2-3.6. System Malfunctions and Their Causes ...................................................... 2-32
2-1
Lubrication PG-4875-C (HOSS)
The importance of selecting the correct lubricating oil and then properly maintaining the
lubricating system cannot be over-emphasized. Using lubricating oil not suited to the
application can shorten the service life of the compressor and lessen its efficiency, as will a
poorly maintained lubricating system. Use only a high grade of oil that meets the general,
physical and chemical requirements as specified in this section.
Do not wait for lubrication difficulties to appear. If there is some question as to the
correct lubricant to use for a particular application, consult a reputable oil supplier.
Lubrication of contact surfaces is intended not only to reduce friction and wear between
parts but also to carry away any heat developed where high speeds and loads are encountered.
If the compressor lubricating system is to accomplish these purposes, it is essential that the
correct oil is used and that the following recommendations for maintaining the lubricating
system are closely observed.
2-2. FRAME AND RUNNING GEAR LUBRICATION SYSTEM
The standard lubrication system is diagrammed in Figure 2-1. The oil is drawn into the
crankshaft-driven gear type oil pump from the frame sump. The pump forces the oil first
through a cooler and then through a filter before it is delivered to the main bearing oil header,
which is a pipe cast into the frame. The oil is delivered to each main bearing through holes
drilled in the bearing saddles to the oil header. From the main bearings, oil passes through
drilled passages in the crankshaft to the crankpin bearing. A rifle-drilled hole in the connecting
rod conducts oil from the crankpin to the connecting rod pin in the small end of the rod. The pin
then feeds oil to the connecting rod bushing and to the crosshead which then feeds oil to the
guides. After passing through and lubricating the various parts, the oil drains back into the
sump area.
LEGEND
PS – LOW OIL PRESSURE SWITCH; (Supplied by Packager)
SET AT 35 PSIG (240 kPa)
RV – PRESSURE CONTROL VALVE;
SET AT 60 PSIG (415 kPa)
TP-5096
Figure 2-1. Typical Frame and Running Gear Lubrication Schematic
With External Oil Pressure Regulation Valve
2-2
PG-4875-C (HOSS) Lubrication
An externally mounted oil pressure regulation valve, a differential pressure gauge and a
low oil pressure shutdown switch are typically incorporated into the standard system. These
items are described in greater detail in the text that follows.
In addition to the standard equipment, optional equipment may be incorporated into the
system for a particular application.
An optional hand-operated priming pump is available to pre-fill all of the oil piping, along
with the oil filter and cooler. The hand pump can also pre-lubricate the bearings and build up a
slight pressure in the lubricating system just prior to start-up. There is a check valve built into
the hand pump to prevent the reverse flow of oil through the priming pump circuit when the main
oil pump is operating.
An optional motor-driven auxiliary oil pump is recommended to pre-fill all of the oil piping
and provides pressurized lubrication to the bearings prior to start-up. The motor-driven
auxiliary oil pump is required on electric motor driven compressors. When the auxiliary oil
pump is used, a check valve must be located in the priming pump discharge line to the main oil
pump discharge.
2-2.1. Main Oil Pump
The main oil pump supplies oil under pressure to the frame and running gear lubrication
system. This pump is internally mounted inside the frame, as shown in Figure 2-2, and is direct-
driven off the end of the crankshaft by a dowel and hub drive arrangement. The oil pump
should not be dismantled unless it has lost capacity.
TP-5097
Figure 2-2. Main Oil Pump and Lubricator Drive Assembly

2-3
All precautionary measures specified by the Occupational

Safety and Health Act of 1970 (OSHA) must be complied with
when storing, handling, or using solvents.
Deposits of hard lacquer in the pump assembly are not usually objectionable unless they
are extensive enough to cause binding. Deposits of this nature in the pump can often be
removed by flushing the pump with a safety solvent, without disassembling it.
A. Main Oil Pump Removal and Disassembly
The main oil pump is internally mounted on the backside of the frame pump end cover
(#1) as shown in Figure 2-2. The frame pump end cover must be removed to gain full access to
the oil pump.
1. Referring to Figure 2-3, if required, remove all the lubricator lines. Using an overhead
hoist and a sling, support the shaft-driven lubricator and then remove the capscrews that
hold the lubricator to the frame pump end cover. Using a straight pull outward to
disengage the lubricator drive shaft, remove the lubricator.
TP-5098
Figure 2-3. Frame Oil Piping and Lubricator Assembly
2-4
2. Disconnect the oil pump suction pipe from the frame pump end cover by removing the
four capscrews (#3) that hold the flange to the cover. Do not remove the 90-degree
suction pipe elbow (#1) from the suction header (#2) unless oil has been drained from
the frame first.
3. Loosen the capscrews that fasten the oil pump discharge piping (#8) to the frame pump
end cover. Also loosen the capscrews that attach the oil pressure regulation valve (#6)
to the end cover. Do not disconnect the oil pressure regulation valve from the oil pump
discharge piping.
4. If required, support the oil cooler piping first, and then disconnect the oil pump discharge
pipe (#8) wherever it is convenient from the oil cooler piping. Attach a sling from an
overhead hoist around the oil pump discharge piping / oil pressure regulation valve and
lightly bump the discharge piping to free the gaskets. Finally remove the capscrews and
lift the entire assembly away from the frame pump end cover.
5. Remove the frame top plate cover and gasket that allows access to the oil pump bay in
the frame.
Compressor cylinders must be depressurized to atmospheric

pressure before barring. Compressor pistons will move to
bottom-dead-center as an equilibrium condition due to the
difference in piston surface area (by piston rod cross sectional
area) exposed to the process gas pressure. Failure to
depressurize the compressor cylinders prior to barring may
result in unexpected rollover that can cause personal injury.
The operator must ensure that the driver will not start, by
grounding the ignition and closing the fuel gas valve on engine
driven units or by ensuring that the power cannot be turned on
with electric motor driven units, before barring the unit over.
Failure to heed the WARNING could result in a fatal accident if
the unit starts unexpectedly.
6. Bar the compressor over until the oil pump drive dowel pin in the end of the crankshaft is
at the 6:00 o’clock position.
When pulling the oil pump and frame pump end cover away
from the frame, be careful not to move the oil pump sharply up
or down or left to right until the oil pump drive hub is clear of
the drive pin located in the crankshaft.
2-5
7. Insert the proper lifting lugs into the top of the frame pump end cover and sling to an
overhead hoist. Referring back to Figure 2-2, remove all the capscrews (#18) that
attach the frame pump end cover to the frame. Carefully pull the pump end cover out
over the dowel pins (#17) being careful not to bend the dowel pin located in the
crankshaft.
8. Install temporary covers over all of the frame openings to prevent entry of dirt or any
foreign objects.
9. Move the oil pump and frame pump end cover assembly to a clean work area. Take
care that the protruding drive shaft and hub are not bent or damaged in the process.
10. Take the drive hub (#14) off the pump drive shaft by removing setscrew (#15). Then
remove the square key (#13) from the drive shaft.
11. The oil pump outer head (#6) and pump body (#3) are removed together by taking out
the long capscrews (#8) that fasten the parts to the frame pump end cover (#1). These
parts are also doweled together. Work carefully when separating the parts so that the
mating machined surfaces are not damaged.
12. The pump gears and their shafts can now be removed from the frame pump end cover.
Before removing the gears, mark them so that they can be re-meshed in the same
relative position.

13. Clean all of the pump parts in a safety solvent and examine the gears, shafts, and
bushings for excessive wear. If these parts are badly worn they can be replaced, but it
is generally more economical to install a complete new oil pump
14. Remove any gaskets and clean all the gasket surfaces in preparation for reassembly.
B. Main Oil Pump Assembly and Installation
1. Replace all O-rings and gaskets with new ones when reassembling.
2. Referring to Figure 2-2, if new shaft bushings (#2) are to be installed, they must be
shrunk fitted (by freezing) into the frame pump end cover (#1). The bushings should be
installed flush to 0.016” (0.40 mm) below the mating gear surface.
3. If new shaft bushings (#7) are required, they also must be shrunk fitted (by freezing) into
the oil pump outer head (#6). Again, the bushings should be flush to 0.016” (0.40 mm)
below the mating gear surface.
2-6
4. Re-install the pump gears (#9) and their shafts (#10 & #11) back into the frame pump
end cover (#1) being sure to re-mesh the gears back into their original relative positions.
5. Reassemble the oil pump body (#3) over the gears and shafts being sure to first place
new plastic gaskets (#5) on each end of the oil pump body (#3). Position the oil pump
body carefully aligning the dowel pins (#4) into the frame pump end cover.
6. Install the oil pump outer head again carefully aligning the dowel pins (#4). Tighten the
eight long capscrews (#8) evenly to the torque value specified in CHAPTER 5,
GENERAL DATA AND SPECIFICATIONS Paragraph 5-3.8 of this Instruction Manual.
The total end clearance for each pump gear should be 0.006 to 0.009 inch (0.15 to 0.23
mm). Turn the pump drive shaft by hand to check for any binding in the pump.
7. Slide the drive hub (#14) onto the pump shaft with the key (#13) in place. Position the
hub 0.500” (12.70 mm), away from the oil pump outer head. Snug the hub setscrew
(#15) against the shaft just tight enough to hold the hub in place during installation.
8. Insert the proper lifting lugs into the top of the frame pump end cover and sling to an
overhead hoist. Remove any temporary covers and install a new gasket (#16) on the
end of the frame. Also install a new gasket on top of the oil pump suction header.
9. Verify that the oil pump drive pin in the end of the crankshaft is at the 6:00 o’clock
position. Rotate the proper slot in the oil pump drive hub (#14) to also be at the 6:00
o’clock position.
When putting the oil pump back into the frame, be careful
when moving the oil pump up or down or left to right to be sure
the drive pin located in the crankshaft enters the drive hub
smoothly.
10. Install the frame pump end cover and pump assembly on the frame, being careful to
align the dowel pins (#17) into the locating holes in the end cover. Start the capscrews
(#18) into the frame to keep the end cover in place but do not tighten.
11. Install the four capscrews that attach the oil pump suction header to the frame pump
end cover but do not tighten. Check that the gasket is properly aligned.
12. Finally, tighten all of the capscrews (#18), along with the four capscrews that attach the
oil pump suction header to the frame pump end cover evenly to the torque value
specified in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-3.8 of
this Instruction Manual.
13. Check that at least 0.250” (6.35 mm) clearance exists between the end of the crankshaft
and the oil pump drive hub. It is important that this end clearance be established to
prevent end thrust on the pump gears. Remove the setscrew (#15) and reposition
the hub if necessary. Lightly apply Loctite® #242 thread-locker to the setscrew threads
and then tighten the setscrew securely.
2-7

14. Bar the compressor over through 360° of rotation to ensure that the crankshaft dowel
pin does not bind in the hub slot in any position and that the oil pump is running freely
and not jammed.
15. Replace the frame top plate cover and gasket.
16. Replace the oil pump discharge piping / oil pressure regulation piping onto the frame
pump end cover using new gaskets. Also re-attach the oil cooler piping and remove any
supports that might have been utilized.
17. Replace the shaft-driven lubricator (if used) on the frame end cover. An O-ring seal is
placed between the parts. Be sure the drive shaft is engaged properly, then tighten the
capscrews. Re-attach all of the lubricator lines.
18. Replace any additional piping and/or frame covers that might have been removed.
Remember to check all of the piping connections for leaks when the unit is re-started.
2-2.2. Oil Pressure Regulation Valve
The oil pressure regulation valve, illustrated in Figure 2-4, controls the oil pressure to the
frame lubrication system. Any excess capacity is then bypassed back to the suction side of the
oil pump. The valve is preset to open at approximately 55-60 PSIG (378-413 kPa). However,
field adjustment may be performed to compensate for differences in oil viscosity. To increase
oil pressure, remove the valve cap (B/J), loosen the lock nut (F) and turn the screw (C)
clockwise. To decrease oil pressure, remove the valve cap (B/J), loosen the lock nut (F) and
turn the screw (C) counter-clockwise. Under normal operating conditions, the oil pressure
should be kept as near to 55-60 PSIG (378-413 kPa) as possible.
2-8
SYM. NAME
A BODY
B CAP
O-RING SEAL
ADJUSTING
C
SCREW
D RETAINER
E O-RING
F LOCK NUT
G SPRING
H STOP RING
I PISTON
J CAP
GASKET SEAL
K GASKET
TP-5099
Figure 2-4. Oil Pressure Regulation Valve
If the regulating valve can no longer maintain system pressure it must be inspected as
follows:

To disassemble the valve, remove the valve cap (B/J) (see Figure 2-4) and its O-ring /
gasket (E/K), then remove the locknut (F), the adjusting screw (C), retainer (D), spring and
piston (G & I) in that order. It is not necessary to remove the stop ring (H) under the piston (I).
Clean the valve parts in a safety solvent and examine the parts for wear and/or scoring. If
required, replace any defective parts. Assembly is the reverse order of the disassembly
procedure.
2-9
2-2.3. Hand Oil Priming Pump
The optional hand-operated pump or optional motor-driven auxiliary pump is used to

pre-lubricate the bearing surfaces and build up a slight pressure in the lubricating system before
start-up. Either of these pumps should require little or no service.
On electric motor driven machines, a motor driven prelube

pump is required. See CHAPTER 5, GENERAL DATA AND
SPECIFICATIONS Paragraph 5-1 in this Instruction Manual, for
the recommended minimum prelube pump capacities.
The hand oil priming pump, Figure 2-5, may be easily serviced by stopping the
compressor, following the stopping procedures found in Chapter 3, OPERATION AND
TROUBLESHOOTING Paragraph 3-8 of this Instruction Manual. Disconnect all of the piping
and plug the opening in the oil discharge piping to isolate it from the system. Finally remove the
mounting capscrews and pump from the frame.
TP-5100
Figure 2-5. Hand Oil Priming Pump

2-10
A. Hand Oil Priming Pump Removal and Disassembly
NOTE
Note the inlet and discharge connections and the relationship of

these to the internal valves. The fill plug (#5) will be located at the
3:00 o'clock position upon proper assembly.
1. Referring to Figure 2-5, loosen the capscrew (#4) and then slide the pump lever (#7) off
from the shaft.
2. Remove all the capscrews (#6), and then pull the lid (#10), wing and shaft assembly
(#8) and oil seal (#9) out of the housing as an assembly.
3. Remove the housing gasket (#11) and clean the mating surfaces.
4. Slide the wing and shaft assembly out of the lid. Using a hook or screwdriver, pry the oil
seal (#9) from the lid. Note the orientation of the seal lips as shown.
5. Lift the suction deck assembly (#13) and discharge deck assembly (#3) out of the
housing (#1).

6. Clean the pump parts in a safety solvent and inspect all parts for wear or damage.
Suction decks, discharge decks and shaft and wing assemblies are sold only as
complete assemblies.
7. Check the locating pins (#12) for damage and replace if required.
B. Hand Oil Priming Pump Assembly and Installation
1. Install the locating pins (#12) if removed, then install the suction deck assembly (#13)
with its valves pointing towards the center of the pump. Install the discharge deck
assembly (#3) with its valves pointing away from the center of the pump.
2. Lightly lubricate the oil seal assembly (#9) and press the oil seal into the lid using an
arbor press or hydraulic press and a suitable seal driver. The oil seal lips must face the
oil to be sealed.
3. Slide the wing and shaft assembly (#8) into the lid.
2-11
SERVICE NOTE
Be careful not to roll the seal lips during this operation. The raised
bosses on the wing should be pointing towards the suction deck so
that the lever can be properly connected.
4. Install the housing gasket set (#11), then slide the lid over the shaft and secure the lid
using the eight capscrews (#6).
5. Check the shaft endplay. If the endplay exceeds 0.008 inch (0.20 mm), remove the lid
and discard one of the housing gaskets.
6. Install the hand lever (#7) and secure it with the capscrew (#4).
7. Replace the pump onto the frame and then install the piping. Operate the pump until all
of the piping is full of oil.
2-2.4. Oil Pressure Gauges
The standard lubrication system comes with a differential pressure gauge that is
installed across the oil filter inlet and outlet to enable the operator to constantly monitor the
condition of the oil filter element. The drop across a new filter element with oil at operating
temperature is usually less than 5 PSIG (35 kPa). Cold oil or a dirty filter will increase the
pressure differential across the filter. Typically, an oil pressure differential of 15 PSIG (104 kPa)
indicates an oil filter element change is necessary. The pressure on the discharge side of the
filter is the approximate oil pressure to the main bearings.
2-2.5. Low Oil Pressure Shutdown Protection
Low oil pressure protection is required and should come in the form of a switch that
monitors the pressure at the end of the main bearing oil header away from the oil pump. The
minimum switch shutdown setting is 35 PSIG (240 kPa) decreasing oil pressure. The packager
typically supplies this switch.
Whenever the compressor is started, visually check the frame

oil gauge to ensure adequate system pressure. This is
necessary as most control systems have the oil pressure
shutdown bypassed for approximately 60 seconds to allow the
unit to start and build up the oil pressure. During this time
there is no protection against low oil pressure.
With the crankshaft-driven main oil pump, it is necessary to keep the low oil pressure
shutdown device inoperative during compressor start-up to allow the unit to start and build up
the oil pressure.
2-12
2-2.6. Oil Cooler (Heat Exchanger)
The standard oil cooler is a shell and tube type heat exchanger with oil in the shell and
water in the tubes. The oil temperature in the frame sump should be maintained within the
range given in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-1 in this
Instruction Manual under normal conditions. Regulating the flow of water through the cooler
controls the oil temperature out of the cooler. The oil cooler must be periodically inspected and
cleaned if necessary.
A regular periodic maintenance schedule should be established and followed with any
heat exchanger. The following procedure is recommended:
1. Drain the coolant and oil from the cooler.
2. Remove the bonnets from the heat exchanger and inspect the tubes for erosion or oxide
deposits. Scrape the pencils to expose a bright, clean surface. If the pencils are
eroded to one-half their original diameter, replace them.

3. Carefully examine the tube bundles for scale or other build-up and clean as required.
After cleaning, always inspect the tubes for corrosion or erosion.
4. Clean all interior surfaces. This can be done in several ways. Many deposits can be
removed by flushing with high-velocity steam or water. For more stubborn deposits,
wire brushing and rodding can be employed. Both shell and tube sides can also be
chemically cleaned. Make sure any cleaning chemicals are thoroughly flushed from the
heat exchanger before putting it back into service.
5. Reassemble the oil cooler. Assembly is the reverse order of the disassembly
procedure.
SERVICE NOTE
At start-up or after maintenance inspection, both shell and tube

sides should be carefully vented and must be completely filled for
proper operation.
2-2.7. Oil Filter
The standard oil filter is frame mounted. This filter is a canister type with a replaceable
oil filter element. A ¾” NPT pipe plug is provided on the side of the filter housing near the
bottom to allow it to be easily drained.
2-13
The oil pressure drop through the filter is monitored by the differential pressure gauge
and the filter element should be replaced whenever the pressure drop exceeds 13 to 15 PSIG
(91 to 104 kPa) with the oil at operating temperature. Pressure drop with clean oil at operating
temperature is approximately 3-5 PSID (21-35 kPa Differential). The flow rate varies depending
upon the viscosity of the oil.
To ensure maximum protection for the compressor, check the filter element frequently
for clogging or channeling. The filter element should be replaced whenever the frame oil is
changed.
This series of oil filters is not available in a duplex or service bypass configuration. You
must install a second filter housing using additional piping / valving to allow for complete filter
assembly bypass if filter maintenance is required without a system shutdown.
Oil filter element replacement is as follows:
Failure to depressurize the filter before servicing element could

result in explosive loss of fluid, damage to equipment and
possibly personal injury.
1. Shut off the flow of oil by stopping the compressor, following the
stopping procedures found in CHAPTER 3, OPERATION AND
TROUBLESHOOTING Paragraph 3-8 of this Instruction Manual.
Depressurize and isolate the filter.
2. Open the ¼” NPT vent plug located on the top lid of the filter ½
turn to vent any pressure in the housing.
3. Drain the filter completely by removing the ¾” NPT drain plug

located on the side of the filter housing near the bottom.
4. Loosen the swing bolt eyelet nuts. Lower the two swing bolts
and open the lid back on the third swing bolt.
5. Rotate the media pack handle to an upright position and utilizing

the handle remove the media pack along with it’s O-rings. The
media pack is most easily removed by rotating while lifting. Set
the media pack aside and allow to drain completely before proper
disposal.

2-14
6. Carefully inspect all the interior surfaces for visible contamination. If required, wash the
canister and core tube assembly with safety solvent. The core tube may be unscrewed
from the housing for cleaning. Agitating the solvent during the process will assist in
removing loose dirt. The canister and core tube should be thoroughly dried before
installing a new oil filter element.
7. Reinstall the drain plug and tighten.
8. Lubricate the new media pack O-rings with clean system fluid. Note that the media pack
is a precision fit element and therefor requires lubrication on the inner diameter of the O-
rings to prevent damage.
9. If removed, screw the center core tube assembly back into the housing. Carefully install
the media pack onto the center tube assembly. Press the oil filter element down until it
is firmly seated.
10. Remove the cap to housing O-ring and clean the sealing surfaces with a lint free rag.
Insert the new O-ring provided with the replacement media pack. Lightly lubricate the
O-ring with clean system fluid and then reinstall the lid on the housing centering the lid
to the swing bolts.
11. Raise up the remaining two swing bolts and hand tighten all of the swing bolt eyelet nuts
in a cross-tightening sequence. Again in a cross-tightening sequence utilizing a bar,
tighten each eyelet nut an additional ½ to ¾ turn in equal increments. DO NOT OVER-
TIGHTEN.
12. If applicable, add oil to fill the canister by utilizing the hand oil-priming pump until oil
comes out of the bleed port. On electric motor driven units, run the prelube pump until
oil comes out of the bleed port.
13. Tighten the vent plug.
14. Run the unit, following the routine starting procedures as outlined in CHAPTER 3,
OPERATION AND TROUBLESHOOTING Paragraph 3-7 of this Instruction Manual.
Bleed the system and check the filter for leaks. We recommend an observed run of at
least ten minutes.
2-2.8. Frame Oil Recommendations
Use a good grade of highly refined oil as recommended by a reputable oil supplier or
company. The oil selected for use, as a frame lubricant, must meet the following requirements.
A. General Requirements
The oil must be well-refined petroleum product with low carbon residue. It should not
contain fats or fixed oil compounding. Oil containing rust and oxidation inhibitors and a foam
depressant is preferred. The oil selected must be substantially non-corrosive to the common
2-15
bearing metals, with a pour point at least 10F (5.6C) below ambient temperature when the unit
is started for engine drives.
Multiviscosity lubricants may be used in the crankcase where widely variable ambient
temperatures are encountered, provided that the lubricant maintains a viscosity of 115 to
150 SSU (23.7 to 31.8 cSt) at normal operating sump temperature.
When heavier lubricants are used to accommodate higher sump temperatures,

crankcase heaters may be required if ambient temperatures fall below 50F (10C) to maintain
the sump temperature above the pour point.
It is recognized that the oil recommended by the engine manufacturer (when an engine
drive is supplied) is normally heavier (in the SAE 40 viscosity range). When this is the case and
the user desires to stock only one oil for use in both the engine and compressor crankcases,
the heavier weight oil recommended for the engine may also be used in the compressor
crankcase.
Under cold ambient starting conditions, it is recommended that the oil sump temperature
be at least 10F to 20F (5.6C to 11C) above the pour point prior to starting for engine drives.
This may require the use of auxiliary crankcase heaters.
If sump oil temperatures are 5˚F higher than the allowable maximum sump temperature
for a specific viscosity, the lubricant should be monitored more closely for nitration effects and
more frequent oil changes should be scheduled to prevent an increase in long term
maintenance programs.
B. Viscosity Requirements
The viscosity requirements for the crankcase oil are as shown in Table 2-1.
Table 2-1. Crankcase Oil Viscosity Requirements

SUMP OIL TEMPERATURE
Below 145F 145-165F 165-180F

(63C) (63-74C) (74-92C)
SAE 20 SAE 30 SAE 40
VISCOSITY AT 100F
(38C)
Saybolt Universal, SSU 420 600 750
Kinematic Viscosity, cSt 90.5 129.5 162.5
VISCOSITY AT 210F
(99C)
Saybolt Universal, SSU 50 60 70
Kinematic Viscosity, cSt 7.3 10.5 13.0
2-16
C. Inspection
Conduct all testing of the lubricating oil in accordance with the Standard Methods (latest
edition) of the American Society for Testing Materials (ASTM).
D. Oil Change Schedule
The oil should be changed every 2000 to 4000 hours, or every 6 months, depending
on local conditions or as indicated by an oil analysis. Most reputable oil companies offer
laboratory analysis services of oil samples on request. We highly recommend the use of this
type of service. A once-a-month analysis schedule is recommended when the compressor is
operated under severe conditions.
Where the compressor is operated in an extremely dirty atmosphere, installed outdoors,

operated intermittently, handling foul gas, or where the oil reaches high temperatures in a very
hot atmosphere, it may be necessary to change the oil more often.
2-2.9. Frame Oil Level
The amount of oil required may vary slightly from the quantities listed in CHAPTER 5,
GENERAL DATA AND SPECIFICATIONS Paragraph 5-1 in this Instruction Manual. There is a
gauge glass located on the pump end side of the frame, which should be checked periodically,
and the oil level maintained as follows:
When the unit is running under normal operating conditions, the oil level should be
maintained to the oil level line in the center of the sight glass. A filler connection is provided on
the pump end side of the frame above the gauge glass for adding oil to the sump.
NOTE
Do not fill to a point where the rotating parts will strike the oil
surface; this will cause foaming and loss of oil pressure from the
main pump. If the oil level is allowed to drop below the gauge glass,
air may be introduced into the oil and then into the oil pump which
could cause a fluctuating or total loss of oil pressure to the bearings.
2-2.10. Frame Breather
The breather(s) mounted on top of the frame vents the frame’s interior to atmosphere
while condensing oil vapors and returning the condensed oil back to the frame sump. Examine
the element at regular intervals and service it as required.

2-17
To service the element, remove the breather's cover and pull out the element. Clean the
element by washing it in a safety solvent and allowing it to thoroughly dry before re-installing.
2-3. CYLINDER LUBRICATION SYSTEM
A mechanical lubricator provides the lubrication of the compressor cylinder bores, and
the pressure piston rod packings. Normally, a metered "Block-type" oil distribution system is
furnished with the oil supply coming from the frame. For some applications, a "pump-to-point"
lubrication system is supplied where each lubrication point is fed from an individual lubricator-
pumping unit. Both systems are described in Paragraphs 2-3.1 and 2-3.2 respectively. With
either method, a check valve is required at the cylinder connection of each oil line to prevent
compressed gas from passing back through the lubrication system.
Recommendations are given in Paragraph 2-3.3 that enables the selection of suitable oil
for a particular application and to determine the optimum feed rate.
For external suction lubricator reservoirs, you must maintain a good grade of lubricant to
lubricate the internal components within the lubricator box. What is recommended is a viscosity
grade of ISO 680 compounded with acidless tallow AGMA-8. This lubricant provides a high
degree of sliding motion, which minimizes wear. It is recommended that this oil be changed at
least every 6 months.
2-3.1. Block-type Lubrication System
TP-5101
Figure 2-7. Typical Block-Type System Schematic
2-18
In a metered block-type system, the compressor cylinders are lubricated by a completely

integrated unit, which is mounted at the pump end of the frame. The unit is directly driven by
the oil pump drive shaft, which is directly driven by the compressor crankshaft. One or more
conventional mechanical “force-feed” lubricator pumping elements pump the oil under pressure
in measured quantities. The number of lubricator pumping elements varies with the number of
cylinders on the frame. See Figure 2-7 for a typical installation.
The system operates as follows:
Oil is pumped into a single main line through a filter and a flow switch. The oil is then
discharged into a primary divider valve assembly. The main metering device is then mounted
on the primary block and typically comes in the form of a switch.
The typical divider block lubrication system will have the secondary blocks mounted
somewhere near or on each cylinder. These blocks are feed from the primary block located
near the lubricator itself. Cycle pin indicators are supplied on each secondary block.
A no-flow switch can be used to sound an alarm, or it can be connected to a shutdown

device on the driver. If a proximity switch is used, the PLC within the panel must then be
programmed for an alarm and an automatic shutdown.
The lubrication system is a single-line, progressive, positive displacement system that

divides the pump output into pre-determined, proportional amounts. It then distributes these
amounts to the points of lubrication. In this type of system, the pistons within each divider block
assembly are cycled by the input flow, continuously dividing and distributing the lubricant until
input flow ceases. By adjusting piston diameters, the amount of lubricant received by one point
can be changed relative to the amount received by other points in the assembly. The piston not
only divides the flow, but also proportions the flow. Due to the valve arrangement, this dividing
and proportioning action starts again when input flow is resumed. This assures positive
lubricant delivery to each point. Figure 2-8 shows how each piston is "valved" by the
completion of a full stroke of a previous piston.
L U B R IC A T IO N
P O IN T
L U B R IC A T IO N
P O IN T
L U B R IC A T IO N
P O IN T
TP-5102
Figure 2-8. Divider Valve Piston Operation
2-19
Each divider valve assembly consists of anywhere from 3 to 8 valve blocks mounted to a
base block. O-ring seals between the base and valve blocks provide leak-proof sealing to
pressures as high as 7000 PSIG (48.3 Mpa). The lubricant outlets are located in the base
block, thus providing easy removal and replacement of worn or contaminated valve blocks
without disturbing the base mounting block or lubrication lines. All valve blocks are
interchangeable to any position on the base block.
One divider valve assembly is capable of serving up to 16 points of lubrication. When

more than 16 points of lubrication are to be served, or when good design dictates, a two-stage
system is employed. The first stage (the master block) proportions the pump flow, which is
subdivided at the second stage (secondary blocks) into the required volumes. In this manner, a
multiple number of points can be properly lubricated from one pump supply.
NOTE
Since the block-type system is based on positive displacement,

never block a point intended to be used or try to feed two points
from one outlet.
The SMX Metering Elements are available in a wide range of deliveries (See Table 2-2).
Cycle indicator pins are available on most size elements. A by-pass element is also available
which allows an addition or reduction of lubrication points at any time without having to
disconnect any piping or tubing. Bridge Elements (Internally Cross Ported) are available.
These interconnect and discharge into the next element. The Metering Elements are supplied
with either one or two outlets. Conversion plugs are available for field conversion from one to
two outlets. All metering elements are fully interchangeable in various positions on the base.
Table 2-2. Oil Output per Cycle

METERING ELEMENT DELIVERY In3 DELIVERY In3
SIZE (TWIN OUTLET) (SINGLE OUTLET)
SMX-08 .005 .010
SMX-12 .0075 .015
SMX-16 .010 .020
SMX-25 .015 .030
SMX-35 .020 .040
SMX-40 .025 .050
SMX-50 .030 .060
SMX-60 .035 .070
SMX-65 .040 .080
SMX-00 By-Pass By-Pass
2-20
The output per cycle of each proportioning piston in any given divider block assembly
and its relative value to other proportioning pistons in the same divider block assembly is shown
in Table 2-2. Valve blocks are marked "T" for twin and "S" for single.
Keep in mind that while the divider block assemblies supply the relative proportions to
the points of lubrication, the total volume of oil to all points of the system for any given time
period is governed by the lubricator pump supply volume.
In some installations, the output from two adjacent valve blocks may be internally
combined and discharged from one outlet. This is called cross porting. Newer blocks are
externally cross-ported.
A. Filling and Purging the System
TP-5103
Figure 2-9. Purging Air from Divider Blocks
To ensure the proper operation of the lubrication system before start-up and/or after an
overhaul, it is imperative that all of the components and tubing be completely filled with the
correct type of clean oil and be free of air.
To properly fill and purge the system:
1. Loosen the tube nuts at each of the injection points. Loosen the tube nuts at the inlets
of all secondary divider valves and loosen the four-sockethead setscrews at the inlet
end of each secondary block. Also loosen all the alternate outlet plugs on the face of
the master divider valve.
2-21
2. Remove one alternate outlet plug from the master divider valve and connect a manual
oil pump to the outlet. (This pump is available from Dresser-Rand. See Figure 2-9.)
3. Operate the manual oil pump until clear, air-free oil appears at the inlet of the secondary
valve then tighten the secondary inlet connection. After tightening the inlet connection,
continue to pump until clear oil emerges from the four-sockethead setscrews, then
tighten the setscrews.
4. Continue to pump until air-free oil is discharged at all injection points served by the
secondary divider, then tighten the tube nuts at these points. After all the lines to the
injection points have been filled and tightened, operate the pump for a few strokes while
checking for leaks.
5. Remove the manual pump from the master divider alternate outlet and replace the plug
fingertight. Connect the pump to another alternate outlet in the master divider and
repeat the procedures outlined above in Steps 3 and 4.
6. After all the master divider alternate outlets have been purged, and all the alternate
outlet plugs replaced fingertight, connect the manual pump to the check valve on top of
the manifold bar.
7. Proceed to loosen the following connections: cap of the atmospheric indicator in the
manifold bar, the inlet connections at the flow-meter, the no-flow valve, the high-
pressure switch and the master divider valve. Also loosen the four-sockethead
setscrews at the inlet end of the master block.
8. Operate the manual pump, filing the system from the manifold bar until clear, air-free oil
appears at each disconnected point in turn. Tighten the loose connections, starting
from the atmospheric indicator in sequence to the master divider inlet and sockethead
setscrews. Continue pumping until clear oil appears at all the master alternate outlets.
Tighten all the alternate plugs in the master so that the entire system is now completely
sealed and oil-tight.
9. Operate the manual pump for a few more strokes to finally check for leaks or
malfunction. Remove the manual pump and plug the check valve.
10. Disconnect the fittings that connect the lubricator pumps to the manifold and operate
each pump manually until a steady flow of air-free oil emerges at the top of the pump
line. This may require the compressor to be rotated in order to manually pump each
plunger.
11. Finally connect the pumps back to the manifold. The system is now ready to operate.
Use the correct, clean and filtered oil in all stems and be sure that the reservoir is
adequately filled at all times.
B. Maintenance and Troubleshooting
Performance indicators are sometimes used to signal excessive system pressure and to
localize problem areas. Pin type indicators use a rupture disc, which bursts at a predetermined
pressure, and causes an indicator pin to remain out until the disc is replaced and the pin is
2-22
manually reset. The rupture disc must be replaced to restore normal operation. Controls, such
as proximity switches, can be installed to sense a pressure signal caused by a blockage. This
signal can then be used to shutdown the compressor or ring an alarm.
A blockage in the lubrication system may be caused by any of the following:
• Crushed tube line in the system

• Blocked or carboned injection point
• Blocked divider valve assembly
• Divider valve assembly bound up
If a blockage occurs anywhere in the divider valve system, proceed as follows:
1. Connect a manual oil pump with a gauge (see Figure 2-9), to the inlet of the master
divider valve and try to cycle the system by pumping oil into the master. If the master
divider is equipped with indicators and the blockage is downstream of the master, one of
the indicator pins in the master will protrude. Blockage is then down stream of the
discharge line common to the protruding pin. If the system will not cycle and/or no
indicator pin is "up" in the master divider, then the blockage is within the master divider
valve.
2. If the master divider valve is not equipped with pin-type indicators, then remove each
alternate outlet plug in the master valve, which is common to a discharge port, one at a
time. When the plug is removed, the trapped lubricant will usually surge out of the
alternate outlet hole, which is common to the blocked out-going line. If there is no
surge, then connect the manual pump to the master alternate outlet being tested and
pump oil into the outlet. If the pressure drops, then there is no blockage down stream of
the discharge line common to the alternate outlet.
3. If the pressure does not drop in Step 2 above for any of the discharge lines in the
master divider valve, then remove all of the alternate outlet plugs. Connect the manual
pump to the inlet of the master divider. While pumping oil into the master, (with all of the
alternate plugs removed), if no oil is discharged at any of the open ports, then the
blockage is within the master divider valve.
4. Proceed to the secondary divider valve, which is downstream from the blocked port, and
remove each alternate outlet plug, which is common to a discharge port. Insert the
manual pump into the alternate outlet port back at the master divider valve, which
serves as the source of lubricant to this secondary valve assembly. Pump oil into the
master alternate outlet. If lubricant is discharged freely through each of the alternate
outlets in the secondary, then the blockage is not in the secondary divider valve but is
downstream of it. If the secondary divider valve will not cycle or discharge lubricant
through the open alternate ports, then the blockage is within the secondary divider
valve.
5. Connect the manual pump into each alternate outlet (one at a time) of the secondary
divider block. If, while pumping oil into one of the secondary alternate outlets, pressure
builds up, then the blockage has been located. Look for crushed lines, or a blocked
injection point.
2-23
Handle all of the parts with great care and ensure complete
cleanliness. These parts are manufactured to very close
tolerances and any nick, scratch, or dirt left on them will
interfere with the proper operation of the divider valve block.
6. If any one of the divider valves is blocked internally, it must be removed, disassembled
and cleaned. Before disassembling the divider valve, remove only the piston enclosure
plugs and with just strong finger pressure, try to work the piston back and forth without
removing it. If all the pistons are moveable, then replace all of the enclosure plugs and
retest the assembly by pumping oil into the inlet. (The particle of dirt, which may have
caused the internal blockage, may now be dislodged and the valve assembly may be
back in working condition with no further service required.)

7. If the piston is jammed, then proceed with further disassembly, first making a note of the
valve block positions on the base (for example: Inlet-35s-16s-12s). With the individual
valve blocks on the bench, remove the piston enclosure plugs. Working with one block
at a time, remove the piston. If the piston appears to be stuck, try removing it from the
other direction. The piston may have to be forced out of the block by lightly tapping it
using a brass rod. After the piston has been removed, flush the piston and block with a
suitable safety solvent. Blow out all the ports thoroughly and use a small piece of a soft
wire to probe the passageways. Inspect the piston and cylinder bore for scratches or
score marks. If either of these parts is damaged, replace the entire valve block. If both
the block and piston appear to be in good condition, reassemble the parts, making sure
that the piston slides smoothly and snugly in the bore. The final step is to disassemble
and clean the base block.
8. After the entire assembly has been cleaned, blown-out, inspected and found to be in
good working condition, assemble the divider valve, positioning the valve blocks on the
base in their original order. Then test the operation of the assembly with a manual oil
pump connected to the inlet port. If it now functions properly, replace the divider valve
assembly back into the system and test the valve for proper system operation.
2-3.2. Pump-to-Point Lubrication System
In a pump-to-point system, the compressor cylinders are lubricated by a mechanical

lubricator, which is mounted at the pump end of the frame. The lubricator is directly driven by
the oil pump drive shaft, which is directly driven by the compressor crankshaft. The main
difference between this system and the block type is that each lubrication point is individually
supplied oil with its own pump. These types of pumps come with sight glasses to allow for
monitoring, as opposed to feed rate monitoring via the divider block cycle time. See Figure 2-10
for a typical lubricator assembly.
2-24
A. Lubricator Operation
The oil in the lubricator sump is forced by action of the individual pumping units through
tubing and check valves to the cylinder bores and piston rod packing. Each pumping unit in the
lubricator is adjustable to permit regulation of the oil feed to the various points. A rocker or roller
type cam follower and cam assembly (see Figure 2-10), causing a plunger piston within the
pump body to reciprocate actuates each pump unit. Adjusting the adjusting sleeve shown in the
drawing will vary the pump stroke, thus the pump output. Maximum output is achieved when the
sleeve is fully extended from the pump body.
As the plunger moves downward in stroke, oil is drawn through the suction check valve
into the plunger bore from the sight feed reservoir. Removing this volume of oil from the sight
feed reservoir creates a vacuum, which causes more oil to be drawn into the reservoir via the
suction tube. A small quantity of oil then enters the sight feed nozzle and drips into the reservoir
below. The quantity of oil can be determined by counting the drops as they fall. As the plunger
moves upward, oil is forced from the plunger bore through the outlet check valve into the feed
line to the lubrication point.
TP-5104
Figure 2-10. Lubricator Pump Assembly
B. Filling and Priming the System
When starting the unit for the first time, prime each lubricator pump as follows:
1. Referring to Figure 2-10, remove the sight feed plug and fill the sight feed about one-
third full of the correct type of clean oil.
2-25
2. Manually operate the pump, using the priming stem, until air-free oil is discharged from
the pump outlet. This may require the compressor to be rotated in order to manually
pump each plunger.
3. Connect the lube feed line to the outlet and continue to hand prime until the line is filled.
Connect the other end of the line to the discharge check valve (one at each lube point)
and pump a few more strokes to fill the check valve.
4. Refill the sight feed to the one-third full mark.
5. Repeat Steps 1 through 4 for each lubricator pump.
6. Check the reservoir to make sure it is filled with the correct type of clean oil to allow for
the adjustment of each pump output.
If the oil level in the sight glass constantly decreases during

operation, it indicates that the vacuum created in the sight feed
is pulling entrained air from the oil as it passes through. If this
continues for any period of time, an air lock in the system can
result. When this occurs, the drops normally seen falling in the
sight glass will cease. Because no oil is getting to the
lubrication point, this can cause serious damage to the
compressor. Air lock can be eliminated by refilling the
lubricator reservoir, loosening the lube feed line at the pump
outlet and manually pumping the unit with the priming stem
until no air bubbles are visible in the oil stream. Note that if a
fairly rapid loss of oil occurs, the cause is often a leak on the
suction side of the pump.
C. Lubricator Adjustment
With the lubricator in operation, observe the number of drops falling through the sight
feed glass over the course of one minute. Adjust the adjusting sleeve to achieve the required
number of drops per minute as specified in the packager guidelines and/or the compressor
lubrication schematic for break-in. As an alternative, see Table 2-3 for typical break-in oil flow
rates required for each cylinder based on a dry natural gas. On a good, airtight assembly it is
normal for the air in the sight glasses to be dissolved in, and gradually replaced by, the oil. This
is of no consequence so long as the lubricator reservoir is maintained full and there are no
suction side leaks in the pumping unit.
2-3.3. Cylinder Oil Recommendations
Four classifications of lubricating oil have been developed to cover the normal
lubrication requirements of compressor cylinders. The physical and chemical properties of the
four oil types generally recommended for these units are listed in Table 2-4. (This table is
general in nature and covers conditions and pressures not necessarily applicable to HOSS
compressors.)
2-26
Selection of the proper type of oil for your particular application normally will be
determined by the discharge pressure and also by the gas quality with respect to "wetness".
Consideration must also be given to the local operating conditions. Review this set of oil
selection instructions with your oil supplier and compare your particular operating conditions
with those listed in Table 2-4 for the various types of cylinder oils.
In addition to the operating conditions given in Table 2-4, the following information also
must be considered when selecting the type of oil to be used in a particular application.
For Type 2 and 3 oils, the gases handled must be dry; that is, gases which do not carry
suspended liquid, contain water vapor or other condensables which remain in the super-heated
vapor state throughout the compression cycle. For Type 2X and 3X oils, the gases handled
occasionally may carry small quantities of suspended liquid into the cylinder or may deposit
some condensation in the cylinder. Type 2 oils are generally used when the operator wishes to
use internal-combustion engine lubricating oil.
Table 2-3. Break-in Oil Feed Drops per Minute (dpm) to Cylinder Plus Packing
CYLINDER DISCHARGE PRESSURE (PSIG)
Cylinder
Diameter
25-150 150-300 300-600 600-1500 1500-3000 3000-7500
(inches)
3–6 10-21 dpm 10-23 dpm 11-29 dpm 14-47 dpm 22-68 dpm 32-107 dpm
4–8 13-28 dpm 13-31 dpm 15-39 dpm 18-62 dpm 29-91 dpm -
8 – 10 27-36 dpm 27-39 dpm 29-49 dpm 36-78 dpm 58-114 dpm -
10 – 12 33-43 dpm 33-47 dpm 37-58 dpm 45-93 dpm 72-137 dpm -
12 – 14 40-50 dpm 40-55 dpm 44-68 dpm 55-109 dpm - -
14 – 16 46-57 dpm 46-63 dpm 51-78 dpm 64-124 dpm - -
16 – 18 53-64 dpm 53-70 dpm 58-88 dpm - - -
18 – 20 60-71 dpm 60-78 dpm 66-97 dpm - - -
20 – 22 66-78 dpm 66-86 dpm 73-107 dpm - - -
22 – 24 73-85 dpm 73-94 dpm 80-117 dpm - - -
24 – 26 80-92 dpm 80-102 dpm 88-127 dpm - - -
> 26 86-94 dpm 86-104 dpm 95-129 dpm - - -
Plus Each
Packing 3-4 dpm 3-5 dpm 4-6 dpm 5-9 dpm 8-13 dpm 11-21 dpm
Case
Approximately 12,000 drops = 1 pint.
2-27
A. General Requirements
These oils are well-refined petroleum products of the general types listed. They should
be prepared from selected stock of either naphthionic or paraffinic type, processed to minimize
deposit formation. Superior rust-preventative properties also are desired. The pour point must
be consistent with the lowest ambient gas intake and cylinder temperatures to be encountered.
The pour point always must be sufficiently lower than the ambient temperature to permit the
proper rate of oil feed by the lubricator. In handling low-temperature gases, select oil of suitably
low pour point, on the basis of intake and cylinder temperatures, to maintain a fluid of lubricant
in the cylinder.
Table 2-4. Standard Cylinder Oil Recommendations
Operating Conditions Type 2 Type 2X Type 3 Type 3X
Discharge Temperature
(F) Max. 350 Max. 350 > 350 > 350
(C) Max. 177 Max. 177 > 177 > 177
Condensed water vapor NO POSSIBLE NO POSSIBLE

present
Suspended liquid present NO POSSIBLE NO POSSIBLE
Special Requirements:
Cylinder with a discharge
pressure of 2000 to 7000 NO NO REQUIRED REQUIRED
PSIG (13.8 to 48.27 Mpa)
Flash Point (F) 380 Min. 380 Min. 410 Min. 410 Min.
(Open Cup) (C) 193 Min. 193 Min. 210 Min. 210 Min.
Viscosity @ 100F (38C)

Saybolt Universal SSU --- 780 Max. --- ---
Kinematic Viscosity cSt --- 168.4 Max. --- ---
Viscosity @ 210F (99C)

Saybolt Universal SSU 60 Min. 72 Min. 105 Min. 105 Min.
Kinematic Viscosity cSt 10.2 Min. 13.3 Min. 21.5 Min. 21.5 Min.
Sulfated Ash 0.50 Max. --- --- ---
Neutralization Value (color);

Total Acid Number --- --- --- ---
Strong Acid Number 0.00 Max 0.00 Max 0.00 Max 0.00 Max
Carbon Residue 0.45 0.45 0.65 0.65

(Conradson) Max. ¹ Max. ¹ Max. Max.
NOTES: ¹ = Ash-free basis
Type 2- Internal-combustion engine lubricating oil of the following classes:

• Straight mineral oil.
• Additive-treated, non-detergent oil.
• Detergent engine oil.
2-28
Type 2X- Compounded compressor cylinder oil with 5% compounding is recommended.

This oil must be capable of providing an improved state of boundary lubrication
and must resist the washing effect of the particular condensate involved.
Type 3- Rust and/or oxidation-inhibited oil or straight mineral oil is acceptable.
Type 3X- Compounded compressor cylinder oil with 5 to 10% compounding is

recommended. This oil must be capable of providing an improved state of
boundary lubrication and must resist the washing effect of the particular
condensate involved.
B. Service Considerations
1. On multi-stage and circular type compressors, or other applications involving high

cylinder discharge temperatures, it is necessary to use higher viscosity oil than is
normal.
The continuous or intermittent carry-over of liquid to

compressor cylinders requires the installation of efficient
separators.
2. When a gas being compressed is saturated with water or hydrocarbons, it is mandatory

that 3X oil be used.
3. Certain lubricating oil additives will cloud the glycerin-water often used in lubricator sight
feeds, necessitating frequent changes of the mixture.
4. On services that are compressing air, it is recommend that a synthetic type lubricant is
used.
C. Inspection
All tests of cylinder lubricants should be conducted in accordance with the Standard
Methods (latest edition) of the American Society for Testing Materials (ASTM).
D. Synthetic Lubricants
In general, our experience with synthetic lubricants indicates that they will do a
commendable lubrication job when the compressor is correctly prepared, the lubricant properly
selected, and the lubricant is supplied in sufficient quantity.
Past experience has shown that it is difficult to properly break in new compressor
cylinders, particularly larger sizes, on synthetic lubricants. Therefore, it is recommended that
cylinders first be broken in (at least 150 hours of running time or until the bore surfaces have
2-29
taken on a glazed appearance) using a 3X oil. After the break-in period switch to a grade of
synthetic lubricant per the lubricant manufacturer's recommendation.
In those few cases where it is absolutely impossible to break in the compressor cylinders
on a mineral oil due to system contamination, note that the danger of cylinder scuffing does
exist. Extreme cleanliness of the suction piping is absolutely mandatory if scuffing is to be
avoided because the film thickness of a synthetic lubricant is generally less than that with a
mineral oil. It is also recommended that the particular grade of synthetic lubricant be on the
higher side of the available viscosity range.
It is important that the quantity of synthetic lubricant fed to the cylinder be ample to wet
the entire bore surface and that an actual visible inspection be carried out within a few hours
after switching to synthetic lubrication to determine that the feed rate is adequate.
It is recommended that the lubricator be adjusted to provide approximately double the

flow of synthetic lubricant as opposed to mineral base oil during the initial start-up and break-in.
Occasionally, compressors must be started and broken in during low ambient

temperatures. Due to the extremely high viscosity index of most synthetic lubricants, take
precautions to ensure that the lubricant is warm enough to flow properly.
It must be again pointed out that synthetic lubricants should not be used in the
compressor unless the unit has been properly prepared first.
2-3.4. Break-in and Operation
Because of the wide range of compressor cylinder sizes and designs, as well as the
varying operating conditions encountered at different compressor installations, it is not practical
to specify a rigid break-in schedule for the compressor cylinders. On compressor units the
break-in of the frame and running gear, as well as the cylinders, are done concurrently with the
load and speed gradually being increased during the break-in period.
The compressor cylinders must be broken in gradually because it is necessary that the
mating parts establish a satisfactory running fit with each other. To do this, there must be a
certain amount of wear between the mating parts. Also, during this break-in period, the
cylinders may be exposed to dirt, welding beads and other foreign material. This is normally the
most critical period in the service life of the cylinder and the demands on the cylinder lubricant
are the most extreme at this time.
Prior to starting the unit for the first time, follow the proper procedures for filling and
purging/priming the lubrication system supplied with the proper break-in oil selected. Refer to
Paragraph 2-3.1 Section A for a Block-Type lubricator system. For a Pump-to-Point lubricator
system, refer to Paragraph 2-3.2 Section B.
During the break-in runs, it is also necessary to feed the maximum amount of lubricant
possible in order to help flush out the wear particles and foreign material.
The following time schedule is generally applicable for lubricating the compressor
cylinders during the break-in period, when the cylinders will ultimately be lubricated with
petroleum based product.
2-30
 For the first full week of operation the lubricator pumping units should be adjusted for
the maximum feed rate. As the cylinder wears in, occasional inspections should be
made to the cylinder bore to see if the walls are taking on a glazed appearance. Should
any trouble develop (usually in the form of increased temperatures) as the oil is being
diluted, increase the pumping rate until a glaze is formed on the cylinder walls.
 It is usually desirable to reduce to a minimum the quantity of oil from the lubricator to the
compressor cylinders and rod packing from the standpoint of oil economy, coupled with
the need to avoid excessive oil in the gas discharge and carbon build up in the packing.
Because of the widely differing conditions under which these units operate (the variety
of cylinder sizes, pressures, temperatures, and types of gas handled) it is impossible to
establish any ironclad rule for the quantity of oil required for cylinder and piston rod
lubrication. The ideal condition is to feed the minimum quantity that will adequately
lubricate the surfaces. This minimum quantity can be established only after several
weeks of operation and experience.
We offer the following as guidelines:
 Under normal operating conditions after break-in, the amount of cylinder oil required for
the various cylinder sizes and pressures is defined as approximately one half (fifty
percent) of the break-in flow rates as displayed in Table 2-3. The normal feed rates are
based on an empirical formula that varies to suit the particular conditions of service of
the compressor cylinders and the type of gas being compressed. These values are the
suggested normal feed rates when clean and dry conditions prevail in the compressor
cylinder. Wet and dirty air or compressed gas may require increased feed rates as
conditions dictate.
 The normal feed rates given are the individual amounts for the cylinder bore and
packing, and are based on an average sized drop (with 12,000 drops equaling one pint
of oil at 75F). Any variation in drop size will require recalculation. To determine the
feed rate for each individual feed, divide the number of drops given in the table by the
number of lubricator lines (feeds) to the cylinder. Adjusting the oil feed rate at the
lubricator will increase or decrease the flow rate the same amount to each lubrication
point. Check all lubrication points to determine the optimum amount. Again, the figures
given are only an approximation. For a more detailed lubrication rate requirement refer
to the packager guidelines and/or compressor lubrication schematic. Good judgement
is required whenever the particular conditions of service are out of the ordinary.
NOTE
The figures given in Table 2-3 are for gravity and vacuum type sight
feed lubrication. Feeds to cylinder bores never should be less than
two drops per feed per minute, under any circumstances.
Oil feed rates to the piston rod packing also will depend upon the condition of the air or
gas compressed. Under normal clean and dry conditions, three to five drops of oil per feed per
minute should be satisfactory. During the first few weeks, it is better to feed too much oil than
too little. After the packing rings have seated themselves on the rod, the lubrication to the
packing should be just enough to maintain a very light film of oil on the rod.
2-31
The compressor cylinder bores, valves, and gas passages should be carefully examined
each time before and shortly after any reduction is made in the cylinder lubrication rate, and the
reduction must be made in small steps. The correct oil feed rate is that which will just maintain
a light film on the cylinder walls. A puddle of oil in the counterbore at the end of the cylinder or
in the discharge passage is evidence of over-lubrication or unsuitable oil. The appearance of
any dry spots on the cylinder walls is definite evidence of inadequate lubrication or an improper
combination of temperature, gas characteristics and oil.
2-3.5. Extended Shutdown

When the compressor is shut down for more than a few days, it is recommended that
precautions be taken to keep the cylinders in good condition during the shutdown period. An
extra quantity of oil should be pumped to the cylinder bore and piston rod packing, by manually
operating the mechanical lubricator pumping units, just prior to shutting down the compressor
when an extended shutdown is planned. Periodically thereafter, oil should be manually pumped
to the cylinders while barring the unit one and a quarter revolutions.
2-3.6. System Malfunctions and Their Causes
1. Pump does not discharge lubricant:

 Empty reservoir
 Air entrainment
2. Pump repeatedly ruptures disc:

 Clogged filter
2-32
 Blocked main line, divider valve or injection point

 Disc pressure rating incorrect for the system
3. Divider valve does not cycle:

 Contaminated or stuck piston
 High pressure downstream; broken tube line serving this valve
4. Divider valve leaks:
 Valve block screws loose
 O-ring not installed
 O-ring damaged
5. Divider valve repeatedly ruptures disc:

 Blocked line downstream
 Blocked injection point
 Improperly drilled tube fitting
 Rupture disc pressure rating incorrect for system
 Divider block bound up
6. Flow meter does not register counts:

 Loss of lube supply
 Broken line
 Inoperative divider valve in flow meter
 Damaged linkage
 Loss of air supply
 Inoperative air valve
 Inoperative air cylinder or counter
7. No-flow valve fails to properly shut down:

 Incorrect adjustment
 Valve improperly installed
 Stuck or contaminated piston
2-33
Form PG-4875-C
DRESSER-RAND OPERATION AND TROUBLESHOOTING
HOSS
CHAPTER 3
Paragraph Page

3-2. PREPARATION FOR INITIAL START .............................................................. 3-2
3-2.1. Alignment Check ......................................................................................... 3-2
3-2.2. Lubrication Systems .................................................................................... 3-4
3-2.3. Compressor Cylinders ................................................................................. 3-5
3-2.4. General Inspections and Adjustments......................................................... 3-6
3-2.5. Compressor Cooling System ....................................................................... 3-6
3-3. CAPACITY CONTROL ...................................................................................... 3-6
3-3.1. Cylinder Clearance Volume ......................................................................... 3-7
3-3.2. Cylinder Unloading ...................................................................................... 3-7
3-3.3. Suction Pressure Control ............................................................................ 3-7
3-3.4. Capacity Control Bypass ............................................................................. 3-7
3-4. COMPRESSOR LOADING AND UNLOADING ................................................ 3-8
3-4.1. Loading/Unloading Procedure – Bypass and Discharge Valve Method ...... 3-9
3-4.2. Loading/Unloading Procedure – Vent Valve Method .................................. 3-10
3-5. INITIAL START-UP ........................................................................................... 3-10
3-6. BREAK-IN AND OPERATION ........................................................................... 3-12
3-7. SUGGESTED ROUTINE STARTING PRACTICES .......................................... 3-13
3-8. ROUTINE STOPPING....................................................................................... 3-15
3-9. EMERGENCY OR NON-SCHEDULED SHUTDOWN ...................................... 3-16
3-10. SHUTDOWN FOR AN EXTENDED PERIOD ................................................... 3-17
3-11. ROUTINE OPERATION AND MAINTENANCE ................................................ 3-17
3-11.1. Daily ........................................................................................................ 3-18
3-11.2. Weekly ........................................................................................................ 3-19
3-11.3. Monthly ........................................................................................................ 3-19
3-11.4. Every Three Months .................................................................................... 3-20
3-11.5. Every Six Months ........................................................................................ 3-20
3-11.6. Annually....................................................................................................... 3-20
3-12. TROUBLESHOOTING BY SYMPTOM ............................................................. 3-22
Table 3-1. Compressor Troubleshooting Chart. ............................. 3-22
Table 3-2. Valve Troubleshooting Chart ......................................... 3-27
3-1
Operation and Troubleshooting PG-4875-C (HOSS)
All operators should carefully read this section before the unit is prepared for its initial
start-up. The purpose of this section is threefold; first, to familiarize the operators with the
requirements of the unit; second, to outline the recommended procedures for starting, loading
and stopping the unit; and third, to assist the operators in setting up an efficient inspection and
maintenance schedule. Optimum performance can be obtained by closely adhering to the
instructions in this section.
After the operators have started the machine a number of times, and have received
experience in caring for it, starting will become a routine procedure. However, there are a
number of special precautions that must be taken when starting a compressor for the first time.
Carelessness or lack of knowledge can result in serious damage to the equipment and to
personal injury. If possible, an experienced erection engineer should supervise the initial start-
up of the unit, and even then, the regular operators should be well acquainted with the details of
the machine, the precautions to be taken when starting, and the reasons behind them.
When the unit is checked out prior to initial start-up, it is an excellent idea to log
important clearances and runout figures. This will establish benchmark readings for these
clearances, which will allow calculation of wear rates and establish a meaningful maintenance
schedule. It is equally important to log these same clearances before/after any major overhaul.
3-2. PREPARATION FOR INITIAL START
NOTE
On a new compressor no internal inspections are required. (If the

machine has set for over 6 months, refer to Paragraph 3-2.3.)
Refer to the instructions supplied by the manufacturer of the

compressor driver when preparing the unit for start-up;
carefully follow the manufacturer’s recommendations. This
also applies when placing into operation accessory equipment
items such as coolers, filters, pumps, and similar equipment.
Thoroughly inspect the entire machine to be certain there are no loose parts or tools
where they can cause damage or interfere with the start-up.
3-2.1. Alignment Check
It is extremely important that the driver-to-compressor

alignment be checked before start-up.
3-2
PG-4875-C (HOSS) Operation and Troubleshooting

A check of the drive alignment is required before starting the unit. The purpose of this
drive alignment is to verify that, during positioning of the skid, the alignment of the driver
driveshaft to the compressor crankshaft has not shifted. The following procedure applies to the
standard flex type of coupling drive arrangement normally supplied:
1. If required, make a suitable fixture to securely mount two dial indicators onto the drive-
coupling hub.
2. After the fixture is securely fastened to the drive-coupling hub, mount a dial indicator to
read radially on the outer rim of the compressor-coupling hub and another indicator to
read axially on the face of the same hub. Preload each dial indicator by rotating the
pointer approximately one revolution on the dial.
3. Rotate the driver through one complete revolution being careful to ensure that the dial
indicators are free to rotate completely around the coupling. Bring both indicators to the
top vertical position with respect to the driver flywheel. Then using a marking pencil or
chalk, place two reference marks, one on the flywheel and the other one on the flywheel
housing in line with each other. These will be the zero reference marks.
4. Mark just the flywheel housing at the 90º, 180º and 270º positions. These marks will be
used as reference points as to when to take the dial indicator readings.
5. Using a bar, shift both the driver driveshaft and compressor crankshaft against their
axial stops in the same direction.
NOTE
In most cases, Dresser-Rand specifies coupling misalignment limits

that are much tighter than those allowed by the coupling
manufacturers. Always adhere to the Dresser-Rand limits.
3-3
6. Zero both dial indicators with the driver flywheel at the top vertical zero reference mark.
Then rotate the flywheel to the 90º mark on the flywheel housing and take both indicator
readings; repeat at the 180º and 270º marks and then return to the starting point. Be
sure the driver driveshaft and compressor crankshafts are first shifted per Step 5 before
recording the indicator readings at each reference point. Back at the starting point, the
indicator readings should be back to zero. If not, re-position the dial indicators and
repeat this Step again.
7. Compare the dial indicator readings to determine the main point of misalignment. If the
readings taken at the 180º reference point indicate that the driver is high or low at the
drive-coupling end, this will, in most cases, indicate that the driver end of the skid is not
properly leveled with respect to the compressor end. Correct this misalignment by
raising or lowering the driver by readjusting the shimming at the driver mounting points.
If further alignment adjustments are necessary, do this by adding or removing shims
from the driver mounting points and/or by moving the driver sideways, if required, using
jack screws against the sides of the driver base.
8. When it has been determined that a any possible misalignment has been corrected by
either raising or lowering the driver, and/or by moving the driver sideways, take a final
set of indicator readings at each of the reference points. The coupling misalignment
should be as close to zero as possible and must not exceed 0.005 inch (0.13 mm) TIR
(Total Indicator Reading) when the equipment is up to operating temperature. Therefore
a vertical tolerance for the difference in thermal growth due to different operating
temperatures between the driver and compressor should be considered when
performing this cold alignment procedure. See CHAPTER 5, GENERAL DATA AND
SPECIFICATIONS Paragraph 5-1 in this Instruction Manual for the nominal operating
temperature of the compressor.
3-2.2. Lubrication Systems
Refer to CHAPTER 2, LUBRICATION Paragraph 2-2 of this Instruction Manual for the
description of the compressor frame and running gear lubrication system. Also refer to
CHAPTER 2, LUBRICATION Paragraph 2-3 for the description of the compressor cylinder
lubrication system. Recommendations for selecting the proper oils for both the frame and
cylinder lubrication will also be found in CHAPTER 2, LUBRICATION. The operator should be
thoroughly familiar with the lubrication requirements of the compressor before starting
the unit.
The following procedure should be used to check the entire frame lubricating system
prior to starting the compressor for the first time:

1. The rust preventative coating applied to the lube system at the factory is soluble with the
recommended lubricating oils and does not need to be removed. If desired, a safety
solvent may be used to remove the protective coating.
3-4
2. Check that all of the oil piping connections are tight.
3. Fill the frame oil sump to the level indicator on the oil level gauge. Refer to CHAPTER
2, LUBRICATION Paragraph 2-2.8 of this Instruction Manual for the proper type and
grade of oil to use. Also in this Instruction Manual, refer to CHAPTER 5, GENERAL
DATA AND SPECIFICATIONS Paragraph 5-1 for the approximate capacity of the frame
oil sump.
4. Dresser-Rand recommends the use of the manual hand pump or motor-driven priming
pump to circulate the oil and fill the lubricating system to prevent the bearings from
suffering from a “dry” start. Air should be continuously vented from the top of the oil
filter while circulating the oil to ensure that no air is trapped in the oil system. Add oil to
the frame sump as required. Do not fill above the oil level mark on the level gauge
because the rotating compressor parts may strike the oil surface, causing foaming and
loss of oil pressure.
5. Continue to operate the priming pump until all the air has been removed from the oil
piping system. On a manual priming pump, continue to pump until a pressure indication
is seen at the oil pressure gauge.
3-2.3. Compressor Cylinders
NOTE
The compressor is normally shipped from the factory with externally

fed lube pumps with oil supplied from the frame oil system. Should
a special oil lubricant be required, please consult with the factory.
1. Fill the lubricator box with a high-grade of lubricating oil. The same oil selected for the
frame can also be used in the lubricator box. This oil is only for the lubrication of the
camshaft, pump rocker arms and the gears inside the lubricator box.
2. Refer to CHAPTER 2, LUBRICATION Paragraph 2-3.3 of this Instruction Manual for the
proper type and grade of cylinder oil. Disconnect all the lubrication lines and prime the
entire system until all of the air is forced out of the lines and air-free oil appears.
Reconnect the lines and cycle the lubricator pumps a short time so the cylinders will be
lubricated as soon as the compressor is started. The lubricator feed(s) should be
initially set for the maximum flow rate. Once the compressor is started, the oil lines will
remain full of oil. After a few days of operation, as the cylinders wear in and the bores
become glazed, the oil feed rate can gradually be reduced. These procedures are
described in full detail in CHAPTER 2, LUBRICATION Paragraph 2-3.
If the machine has set for over 6 months proceed with the following:
1. Remove the outer head and the inboard suction valve assembly from each compressor
cylinder and inspect the cylinder bores.
2. If the cylinder walls are rusty and pitted, then follow the cylinder instructions located in
this Instruction Manual in CHAPTER 4, MAINTENANCE Paragraph 4-11 through 4-14
on how to remove, hone and re-install the cylinder.
3-5
SERVICE NOTE
For cylinders operating in a non-lube service, DO NOT re-coat the

cylinder walls with lubricating oil.
3. If the cylinder walls are clean, then re-coat the cylinder walls with lubricating oil and
replace the outer head and inboard suction valve assembly for each compressor
cylinder.
3-2.4. General Inspections and Adjustments
1. Check the torque and tighten as required, all the bolts and nuts to be sure that the unit
is ready for start-up. Refer to CHAPTER 5, GENERAL DATA AND SPECIFICATIONS
Paragraph 5-3 of this Instruction Manual for the specific tightening recommendations.
2. The piston rod runout has been checked and the piston end clearances have been set
at the factory. However, if an outboard cylinder support has been installed in the field,
then the rod runout must be checked prior to starting the unit. Refer to CHAPTER 4,
MAINTENANCE Paragraph 4-10.2 in this Instruction Manual for the detailed procedures
on how to check and adjust the piston rod runout. The final runout readings should be
recorded for future reference.
3. Prepare the compressor driver and all other accessory equipment for initial starting and
operation per the manufacturer’s recommendations.
3-2.5. Compressor Cooling System
1. Run coolant through the shell and tube type compressor oil cooler to be sure the cooling
system is operative and that all the water and oil connections are tight. Vent the
waterside of the cooler and the high points in all the piping to remove any trapped air.
3-3. CAPACITY CONTROL
Capacity control, as used in this context, is any means of varying the capacity of the unit
to meet the conditions under which the unit is applied. For most engine driven compressors,
the simplest method of capacity control is by varying the speed of the driver. Another, more
long-term adjustment, involves changing the cylinder sizes. This section covers four of the
more common methods used to vary the capacity for shorter durations. The first is by adding
clearance volume to the cylinder to reduce the volumetric efficiency of the cylinder. The second
is by cylinder unloading. The third is by varying the suction pressure through use of a suction
pressure control valve. The fourth method is through the use of a bypass system. Each
method will be discussed in more detail in the following sections.
3-6
3-3.1. Cylinder Clearance Volume
The standard compressor cylinder may be equipped with unloading devices to add
clearance volume to either the frame end or outer end inlet valves of the cylinder. The outer
head may also contain either a fixed volume clearance plug or a clearance pocket, either fixed
volume or variable volume. The fixed volume clearance pockets are operated by external
pressure from an external source and are typically controlled via PLC. The variable volume
clearance pockets (VVCP) are operated manually by means of dual handle wrenches.
The VVCP can be adjusted while the machine is in operation OR when the machine is
shut down and the cylinder depressurized. Also, an external position indicator sight glass on
the VVCP shows the relative percentage of the clearance volume added. For details on the
operation and maintenance of the VVCP, see CHAPTER 4, MAINTENANCE Paragraph 4-20.2
in this Instruction Manual.
When the clearance volume is modified, the actual cylinder performance should be
checked for adequate rod reversal and volumetric efficiencies. This method of capacity control
also reduces the horsepower requirements proportionally to the reduction of flow.
3-3.2. Cylinder Unloading
Unloading of a cylinder end is accomplished by retracting the suction valve. This has
the effect of reducing the capacity of the machine by the amount of flow the unloaded end is
capable of generating. For details on the operation and maintenance of the unloaders, see
CHAPTER 4, MAINTENANCE Paragraph 4-20.1 in this Instruction Manual.
Unloading sequences not initially approved or reviewed can lead to overloads, non-
reversal rod loads, overheating, and/or valve reliability problems. Consult with a Dresser-Rand
representative if such unloading sequences have not been approved. This method of capacity
control reduces the horsepower requirements by approximately 50 percent.
3-3.3. Suction Pressure Control
Controlling the suction pressure to the compressor can also be used to control capacity.
This is most often used when horsepower is limited and the flow rate is higher than the unit can
handle. A suction control valve is used to hold the suction pressure to a preset limit, thereby
limiting the flow. Performance must be run at the desired set point to ensure that temperature
and rod load limits of the compressor are not exceeded. This method of capacity control offers
the advantage of a stable operating condition for the unit.
3-3.4. Capacity Control Bypass
A unit bypass system may be used to control capacity, particularly when the unit is
oversized, or when the suction pressure is not stable and has a tendency to fall below a
desirable limit. This method utilizes a pressure control valve in the bypass system around the
unit, set to operate at the minimum operating point for the compressor. When this method is
used, it is important that the bypass gas stream be taken downstream of a process aftercooler.
This will avoid an uncontrolled temperature rise during continuous operation. Figure 3-1
illustrates a typical bypass system.
3-7
TP-5105
Figure 3-1. Bypass Capacity Control
3-4. COMPRESSOR LOADING AND UNLOADING
It is important that the compressor be unloaded prior to and during startup. There are
two basic methods to loading and unloading the HOSS compressor. Which of the two is best
suited for a particular installation depends on the site conditions. The following should be
considered prior to designing the piping system:
The two methods are as follows:
• Bypass and discharge check valve method

• Vent valve method
Probably the simplest, most reliable and safest method is by the use of a bypass and
discharge check valve. This is illustrated in Figure 3-2. With this set-up, there is little danger of
exceeding the rated rod load and the rate of loading can be controlled by the rate of closing of
the bypass valve. On multiple-stage units, this set-up works well for sequence loading because
each block valve is opened or closed separately. It should be noted that with this method, when
the compressor cylinders and piping are pressurized to suction gas pressure, the load on the
unit would be dependent on the sizing of the bypass valve and the associated piping. Also the
sizing of the bypass valve and piping will be the limiting factor on the period of time the unit can
be bypassed without excessive gas heating.
3-8
TP-5106
Figure 3-2. Bypass and Discharge Check Valve Method
3-4.1. Loading/Unloading Procedure – Bypass and Discharge Check Valve

Method
1. Prior to starting the unit, be sure that the suction and discharge valves are closed.
Then, open the bypass valve and the vent valve to de-pressurize the compressor
cylinders and piping to atmosphere.
2. Start the driver. If the driver is an engine, allow it to idle and warm up. After ten minutes
of warming-up, bring the engine up to a fast idle.
3. Open the discharge valve, which will allow discharge pressure to back up against the
discharge check valve.
4. Partially open the suction valve to purge the compressor cylinders and piping.
5. Pressurize the compressor cylinders and piping by closing the vent valve and opening
the suction valve.
6. Load the unit by closing the bypass valve.
7. Reverse the proceeding Steps to UNLOAD.
The other method of loading and unloading is the vent valve method. This is illustrated
in Figure 3-3. This method results in the venting of excess gas during loading which may not be
acceptable in certain situations at particular sites. Also, during the idling periods the
compressor will pull a partial vacuum on the suction piping downstream of the suction valve,
and it is extremely important that the unit is purged prior to loading. Additionally, the suction
valve must be fully open prior to closing the vent valve to prevent the possibility of generating
excessive rod loads.
3-9
TP-5107
Figure 3-3. Vent Valve Method
3-4.2. Loading/Unloading Procedure – Vent Valve Method
1. Prior to starting the unit, be sure that the suction and discharge valves are closed.
Then, open the vent valve to de-pressurize the compressor cylinders and piping to
atmospheric pressure.
2. Start the driver. If the driver is an engine, allow it to idle and warm up. After ten minutes
of warming-up, bring the engine up to a fast idle.
3. Open the discharge valve, which will allow discharge pressure to back up against the
discharge check valve.
4. Partially open the suction valve to purge the compressor cylinders and piping.
5. Load the unit by opening the suction valve fully, then closing the vent valve.
6. Reverse the proceeding Steps to UNLOAD.
3-5. INITIAL START-UP
When starting the compressor for the first time, it is extremely important that the
operators are alert for unusual or abnormal pressures, temperatures, noises and other
conditions. Indicating gauges and thermometers should be closely monitored during this initial
starting period.
Read the following break-in instructions before starting the compressor. The procedure,
which follows, applies generally to the initial start of the unit. However, some modifications to
this procedure may be required when starting a particular machine.
1. As far as it is practical, check the inlet and discharge lines for any foreign objects.
Check all the suction and discharge line valves for the proper location, flow direction
and position.
3-10

2. Operate the priming oil pump to pre-lubricate the compressor bearings and to build up a
slight pressure in the frame and running gear lubrication system.

3. Manually operate each lubricator-pumping unit by pushing down on the priming stem to
ensure that oil is being fed into the cylinder bores and piston rod packing. The motion of
the cycle indicator pin in the distribution blocks can confirm this. This may require the
compressor to be rotated in order to manually pump each plunger.
4. Follow the unloading procedures to ensure that the unit is properly unloaded as outlined
in Paragraph 3-4 in this Instruction Manual depending upon the type of system installed.
5. Walk around the machine to double check that all of the equipment is ready for start-up,
and that all personnel in the area are aware that the unit will be started.
6. If fitted, release the driver flywheel lock. Bar the compressor over a few times to be sure
all of the moving parts are clear and also to be sure that lubricating oil is distributed to
all the running surfaces. Make sure that the barring device is disengaged and placed in
the locked position prior to start-up.
7. Turn on the cooling water and check to be sure that the cooling system is operative.
Check for leaks and repair if necessary.
3-11
Never operate any compressor at the maximum speed with no

load applied. The piston rod load may be exceeded at this
condition. Also, never operate the compressor at a speed less
than 500 RPM.
8. Prepare the driver for start-up according to the manufacturer’s instructions.
The machine must be immediately shut down if an abnormal

condition exists, and the cause found and corrected before
restarting the unit.
9. Start the driver and closely observe the frame oil pressure and check the cooling water
temperature. Watch for signs of excessive heating, unusual noises and/or other
abnormal conditions.
10. If everything appears normal, then continue to operate the unit continuously for 30
minutes at the no load condition. On engine driven units, the engine speed can be
varied from idle to mid-range speed during this period.
11. At the end of the 30-minute period, if no problems are identified, the compressor is
ready to purge and load for the operation and service that the unit is intended for. When
placing the unit in service, pay particular attention to the break-in considerations that are
given in the following instructions.
NOTE
Verification of proper bore lubrication is not final until the bore

has been checked after the unit has run under full load and
been shut down. The lubrication rates vary depending on the
load conditions.
3-6. BREAK-IN AND OPERATION
Compressor cylinder clearances should be set up according to

the performance data sheets before loading.
1. The normal procedure for “breaking-in” a new compressor involves several short runs at
gradually increasing speed and load. The type of driver and the particular operating
conditions will dictate the actual break-in requirements and procedures.
2. Because of the wide range of operating conditions, it is not practical to give specific
break-in recommendations for the cylinders. The instructions in CHAPTER 2,
LUBRICATION Paragraph 2-3.4 of this Instruction Manual are general and should be
modified as required to suit a particular situation.
3-12
3. Sometime during the break-in period after a full load condition has been run, while the
unit is not in operation, tighten the cylinder mounting flange nuts, packing gland nuts
and all other exposed nuts and bolts. When gaskets are first subjected to full load and
operating temperature conditions, the material will crush. If the gasketed joints are not
tightened up at this time, oil, water, or gas leaks may start later or stud breakage may
occur. Also check all of the foundation bolts to ensure that they are tight. Refer to
CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-3 of this
Instruction Manual for the specific tightening recommendations.
3-7. SUGGESTED ROUTINE STARTING PRACTICES
The routine starting procedure, which follows, is for a typical compressor equipped for
manual starting. Some modifications to this procedure may be required to suit a particular
compressor and drive arrangement. However, it is important that a standard starting sequence
be established and followed consistently by the operators.
1. Check the oil level in the frame sump and add the proper type of oil as required to bring
the level up to the full mark on the oil level gauge.

2. Operate the priming oil pump to pre-lubricate the compressor bearings and to build up a
slight pressure in the frame and running gear lubrication system.

3-13
3. Manually operate each lubricator-pumping unit by pushing down on the priming stem to
ensure that oil is being fed into the cylinder bores and piston rod packing. The motion of
the cycle indicator pin in the distribution blocks can confirm this. This may require the
compressor to be rotated in order to manually pump each plunger.
NOTE
If the compressor has been opened to the atmosphere, it should be

purged with process gas before being put on line to ensure that no
oxygen is present in the cylinders or piping.
4. Unload the compressor. The method of starting-unloading must be established for each
compressor, but it is generally accomplished through the use of a manual bypass
system. Blow down the unit prior to starting. Follow the unloading procedures to ensure
that the unit is properly unloaded as outlined in Paragraph 3-4 in this Instruction Manual
depending upon the type of system installed.
5. Walk around the machine to double check that all of the equipment is ready for start-up,
and that all personnel in the area are aware that the unit will be started.
6. If fitted, release the driver flywheel lock. Bar the unit over once to be sure that all of the
moving parts are clear. This is especially important when the unit has just been
serviced. Make sure that the barring device is disengaged and placed in the lock
position.
7. Turn on the cooling water and check to be sure that the cooling system is operative.
Never operate any compressor at the maximum speed with no

load applied. The piston rod load may be exceeded at this
condition. Also, never operate the compressor at a speed less
than 500 RPM.
8. Prepare the driver for start-up according to the manufacturer’s instructions.
3-14

9. Start the driver and run the compressor at the no load condition for 10 minutes or until
the frame oil warms up to 90ºF (32ºC). If required, refer also to the driver instructions
for its warm-up requirements. (When starting an engine driven compressor, the unit is
normally warmed up at 800 to 900 RPM and then the load is applied before bringing the
machine up to the operating speed.)
10. When the unit is warmed up and determined to be operating satisfactorily, without any
unusual noises, the compressor cylinders can then be loaded. Follow the loading
procedures to ensure that the unit is properly loaded as outlined in Paragraph 3-4 in this
Instruction Manual depending upon the type of system installed. Build up the discharge
pressure gradually, typically by slowly closing the manual bypass valve. Note the
discharge gas temperatures while loading (abnormal temperatures are often the first
indications of trouble).
11. Adjust the cooling water flow, if required.
12. When the temperatures and pressures have stabilized, record them for future reference
as standard operation and maintenance guidelines.
3-8. ROUTINE STOPPING
Never operate the compressor at a speed less than 500 RPM.
1. When the compressor driver is an engine, it should be slowed to idle speed.
During normal operations, cylinder O-rings may become

saturated with gas, especially at pressures above 1000 PSIG.
When a compressor is blown down too rapidly, the O-rings
may blister due to the rapid escape of the gas from the O-rings.
This is known as explosive decompression. To avoid this, a
compressor should be blown down at a moderate rate allowing
the gas to escape the O-rings without blistering. If this
situation should arise, consult your nearest Dresser-Rand
Distributor.
3-15
2. Unload the compressor. A standard unloading procedure should be established for

each compressor as they may not all be manual, but it is usually accomplished by slowly
opening the bypass valve. Follow the unloading procedures to ensure that the unit is
properly unloaded as outline in Paragraph 3-4 of this Instruction Manual depending
upon the type of system installed.
3. Allow the compressor to operate at the no load condition for several minutes to cool.
4. Stop the driver according to the manufacturer’s instructions.
5. Shut off the cooling water to the cooling system and cylinders.
6. Prepare the compressor and driver so that they can be restarted, if required on short
notice.
3-9. EMERGENCY OR NON-SCHEDULED SHUTDOWN

1. If any emergency occurs requiring the immediate shutdown of the compressor, the
compressor can be shut down under load.
During normal operations, cylinder O-rings may become

saturated with gas, especially at pressures above 1000 PSIG.
When a compressor is blown down too rapidly, the O-rings
may blister due to the rapid escape of the gas from the O-rings.
This is known as explosive decompression. To avoid this, a
compressor should be blown down at a moderate rate allowing
the gas to escape the O-rings without blistering. If this
situation should arise, consult your nearest Dresser-Rand
Distributor.
2. In the event of an automatic safety shutdown, the operator should immediately check to
find the cause of the shutdown. If the problem is not readily apparent, the operator
should slowly relieve the system of pressure before making a more thorough
examination.
3. If it appears that the compressor will not be operating again within ten minutes, turn off
the water flow to the cooler and cylinders.
3-16
3-10. SHUTDOWN FOR AN EXTENDED PERIOD

1. If the compressor is to be shut down for less than a month, then either the manual frame
oil priming pump or the electric driven prelube pump and the cylinder lubricator pumps
should be operated every two - (2) weeks for a few minutes. The unit should be barred
over one and a quarter revolution to ensure to lubricate all of the internal components.
2. If the compressor is to be shutdown for more than a month, the compressor frame and
cylinders should be preserved.
3. Refer to the manufacturer’s recommendations for the driver and all other accessory
equipment when planning an extended shutdown of these items.
3-11. ROUTINE OPERATION AND MAINTENANCE
The HOSS compressor is designed and built for long periods of continuous full-load
operation and should be equipped with automatic safety switches to shut it down in case of low
frame oil pressure, vibration, or lack of cylinder lubrication. It can also be equipped with
additional safety devices to obtain practically any degree of protection desired.
When the unit is first placed in operation and the machine is operating at normal speed
and load and with stable operating pressures and temperatures, all safety alarm and shutdown
controls should be carefully checked for correct operation. Never disconnect the safety
shutdown devices and allow the unit to run unprotected.
Every compressor requires a certain amount of supervision and care if it is to give

continued satisfactory performance and long service life. A time schedule of duties for the
operator must be subject to alteration by experience to fit the actual conditions. The following
minimum schedule is suggested based on the continuous duty of 720 hours per month.
3-17
NOTE
The time schedule of routine inspections and maintenance for the

compressor must be used in conjunction with the schedule and
duties recommended by the driver manufacturer. This also applies
to the other accessory equipment.
3-11.1. Daily
1. Keep the exterior of the compressor/driver clean, as well as the surrounding work area.
2. Check the oil level in the frame sump and add the proper oil as required to maintain the
level at the oil level line on the gauge. Check that the oil tank (if so equipped) is also
filled to the proper level.
3. Check the oil level in the lubricator drive box and add the proper oil as necessary. If the
oil level has increased, then check the pumps for leakage past the plungers. Make sure
that all the pumping units are working and also inspect the distribution blocks for
leakage, indicator pins “popped up”, or other problems.
4. Keep an hourly log of all the gas temperatures, water temperatures and gauge
pressures. One of the principal means of keeping track of the physical condition of a
compressor and its equipment is by these hourly readings. Watch carefully for any
marked changes that indicate that further attention is warranted. Use the interstage
pressures and temperatures to detect abnormal conditions. A decrease in the
interstage pressure and temperature means that the lower pressure cylinder has
reduced capacity. An increase in interstage pressure and temperature means that the
next higher stage cylinder has reduced capacity. These effects can be attributed to
leaking valves, worn piston rings or broken parts.
SERVICE NOTE
In every case, because of the variable operating conditions, the

operator should establish the frequency of draining off the various
drains. This frequency will be determined by the amount of liquid
that collects at each drain point.
5. If separators are used in the compressor system, a schedule must be established

whereby they are periodically drained to prevent a liquid carryover into the compressor
cylinders, which can cause serious damage. If automatic drains are furnished, check
them for proper operation and be sure that no liquid has accumulated in the level gauge.
6. Drain all the low points in the discharge piping.
7. Check all the gas, water and oil piping for leaks.
8. Watch for signs of excessive heating and listen for any unusual noises while the
machine is operating. Any abnormal condition should be investigated immediately.
3-18
3-11.2. Weekly
1. One week after start up, check the fasteners on joints with gaskets and the entire
cylinder to frame bolting. Take note of any fasteners that have loosened and pay close
attention to these fasteners. Increase the periodic checking of these fasteners.
2. Also one week after start up, check the runout of the compressor piston rods. Make
sure the piston rod is not scored. Then check the runout every three months thereafter.
3. Inspect all the loaded joints for motion across the joint during operation. Tighten the
fasteners as required following the procedures outlined in CHAPTER 5, GENERAL
DATA AND SPECIFICATIONS, Paragraph 5-3 in this Instruction Manual.
4. Check the oil scraper packing, piston rod packing and distance piece vents for
excessive blowby and/or oil leakage. If blowing, determine the cause and if required,
replace the packing rings.
3-11.3. Monthly (ALL WEEKLY checks plus:)
NOTE
When the compressor is being operated in an extremely dirty

atmosphere, or where it is installed outdoors, operated
intermittently, handling foul gas in the cylinders, or operating with
high oil temperatures in a very hot atmosphere, it may be necessary
to change the oil more often. Most reputable oil companies offer
laboratory analysis of oil samples, the use of this type service is
recommended.
1. Take a sample of the frame oil for analysis. Compare the oil analysis to one made on a
fresh sample of oil taken straight from the drum. Change the oil and filter per the
analysis or per the compressor manufacturer's recommendations.
2. Lubricate all of the variable volume clearance pocket (VVCP) packing grease fittings
(see CHAPTER 4, MAINTENANCE Paragraph 4-20.2 of this Instruction Manual) and
check for free motion by moving the pocket in and out with the unit not operating. Reset
the pocket to the correct clearance setting.
3. Check all of the safety shutdowns and the operation of loading and unloading devices
for proper operation.
4. Check the frame breather(s) and clean or replace the elements as needed.
5. Clean the lubricator reservoir and pumping units as necessary or according to the
manufacturer’s instructions.
3-19
3-11.4. Every three Months (ALL WEEKLY and MONTHLY checks plus:)
1. Check the crosshead-to-guide clearances using feeler gauges.
2. Check the runout of the compressor piston rods.
3. The frame lubricating oil should be changed after 2000 to 4000 operating hours or as
the monthly oil analysis indicates. Always clean the filter housing and install a new filter
element when the oil is changed.
4. Check the compressor piston rings and piston rod for wear and the cylinder bore for
scoring, and remove any accumulation of foreign material. Replace the piston rings if
they are worn to their limit. See CHAPTER 4, MAINTENANCE Paragraph 4-15 in this
Instruction Manual for the proper procedures on checking the wear rate of, and
renewing, TFE piston and rider rings.
5. Check the accuracy of the compressor pressure gauges on a dead weight tester.
Recalibrate the pressure gauges as required.
6. Remove all the inlet and discharge valves. Clean and inspect the valves for excessive
wear and broken parts. Lap both the seats and guards. Refer to the compressor
cylinder instructions.
7. Clean the separator sight glasses (if so equipped).
8. Inspect the Beta drive shaft seal (if so equipped) and replace it if required.
9. Check the frame and driver foundation bolts for tightness. Follow the required
procedures and tighten to the proper torque valve given in CHAPTER 5, GENERAL
DATA AND SPECIFICATIONS Paragraph 5-3 found in this Instruction Manual.
10. Inspect the drive coupling. Replace any worn or broken components. Tighten as
required.
3-11.5. Every Six Months (ALL QUARTERLY checks plus:)
1. Check the crankshaft endplay.
2. Check the piston end clearances.
3. Remove, clean and inspect the piston rod pressure packing rings and oil scraper rings.
Renew the rings as required.
3-11.6. Annually (ALL SIX MONTH checks plus:)
1. Check all of the running gear clearances and compare them to the benchmark readings.
If a change is detected, disassemble and inspect those affected parts. Replace any
worn or broken parts
2. Clean and flush the oil cooler and any other heat exchanger supplied.
3-20
3. Remove the compressor pistons and inspect the rings. Record the cylinder bore
diameters. Inspections of this nature will indicate the replacement schedule for parts
that are subject to wear.
4. Safety valves used in the compressor gas system should have their settings tested at
least once a year, and more often under extreme conditions, by a hydraulic test.
5. Examine any separators, bottles, dampers and similar equipment that may be used in
the compressor system for accumulation of dirt, rust and other foreign material.
Remove the vessel from the system and clean it if necessary.
6. Visually inspect the packing cups; re-lap as required.
7. Remove and inspect both the main bearings and the connecting rod bearings.
3-21
3-12. TROUBLESHOOTING BY SYMPTOM
Table 3-1. Compressor Troubleshooting Chart
TROUBLE PROBABLY CAUSE(S) REMEDIES
COMPRESSOR WILL 1. Power supply failure. 1. Restore power supply.

NOT START (Motor Drive Only)
2. Switch gear or starting 2. Check circuitry, interlocks,

panel. Relays. See vendor
(Motor Drive Only) literature.
3. Oil pressure permissive to 3. Check oil pressure at

start switch. header using aux. pump;
adjust or replace switch.
4. Control panel. 4. Check electrical

connections and settings.
5. Cylinders pressurized. 5. Unload cylinders.
6. Running gear blocked. 6. Unblock to allow rotation.
7. Barring device/lock 7. Disengage barring rig or

engaged. lock.
MOTOR WILL NOT 1. Low Voltage. 1. Correct source of low

SYNCHRIONIZE voltage.
(Motor Drive Only)
2. Excessive starting torque. 2. Unload compressor for
starting.
3. Incorrect power factor. 3. Adjust rheostat.
4. Excitation voltage failure. 4. Correct exciter problem.

See Manufacture’s literature.
NOISE IN CYLINDER 1. Loose piston 1. Tighten piston assembly to

piston rod per instructions.
2. Piston hitting outer head 2. Adjust end clearance to

or frame head. specifications.
3. Loose crosshead jam nut. 3. Tighten jam nut.
4. Broken or leaking valve. 4. Repair or replace valves.
5. Piston rings broken. 5. Replace piston rings.
6. Liquids. 6. Remove liquids.
3-22
Table 3-1. Compressor Troubleshooting Chart Continued
FRAME KNOCKS 1. Loose crosshead pin caps 1. Tighten and/or replace

or crosshead shoes. loose parts.
2. Loose or worn main, 2. Check clearances and

crankpin bearings or replace bearings or
crosshead bushing. bushings as required.
3. Low oil pressure. 3. Increase oil pressure; repair

(See below.) leaks.
4. Cold oil. 4. Warm oil before loading

unit; reduce the coolant
supply to the oil cooler.
5. Incorrect oil. 5. Use the proper type of oil

per the specifications in this
Instruction Manual.
6. Knock is actually from 6. Tighten piston nut, etc. refer

cylinder. to “Noise in Cylinder”.
LOW OIL PRESSURE 1. Oil pump cavitation. 1. Replace worn oil pump.
1A. Oil Level too low in sump.
2. Oil foaming from rotating 2. Reduce oil level in sump.

parts hitting oil surface.
3. Cold oil. 3. Utilize frame oil immersion

heater or steam-trace
piping.
4. Dirty oil filter. 4. Replace element(s); clean

filter can.
5. Excessive oil leakage at 5. Excessive clearance,

bearings. replace bearings.
6. Oil pressure regulation 6. Set (RV) valve per the oil

valve (RV) incorrectly set. pressure specifications in
7. Low pressure relief valve 7. Adjust and/or replace relief

setting. valve.
8. Defective gauge. 8. Replace gauge.
9. Plugged sump suction 9. Clean suction strainer.

strainer.
3-23
CRANKSHAFT OIL 1. Faulty seal installation. 1. Reset seal per the

SEAL LEAKS specifications in this
Instruction Manual.
2. Clogged drain hole. 2. Clear obstruction.
OIL SCRAPER 1. Worn scraper rings. 1. Replace rings.

LEAKAGE
2. Scraper rings incorrectly 2. Assemble per the
assembled. specifications in this
Instruction Manual.
3. Worn or scored piston rod. 3. Replace piston rod.
4. Ring side clearance 4. Replace rings.

excessive.
PACKING LEAKAGE 1. Worn packing rings. 1. Replace the packing rings.

AND/OR BLOWBY
2. Improper lube oil or lube 2. Use the proper type of oil
oil feed rate. (Piston rod per the specifications in this
turns “Blue Hot” in color.) Instruction Manual;
increase the feed rate.
3. Dirt in packing. 3. Clean the packing and

piping; ensure that the gas
supply is clean.
4. Discharge pressure 4. Reduce the pressure and

increased too fast. increase at a lower rate.
5. Rings incorrectly 5. Assemble per the

assembled. specifications in this
Instruction Manual.
6. Improper end or side 6. Check and adjust

clearance. clearances.
7. Packing vent plugged. 7. Unblock and provide low-

point drains.
8. Scored piston rod. 8. Replace the piston rod.
9. Excessive rod runout. 9. Check the crosshead

clearances and piston to
bore clearances. Re-shim
the crosshead shoes to
adjust the rod runout.
3-24
PACKING 1. Lubrication failure. 1. Replace the check valve or

OVERHEATING lubricator pump.
2. Improper lube oil or feed 2. Use the proper type of oil

rate. per the specifications in this
Instruction Manual; increase
the feed rate.
3. Insufficient cooling. 3. Clean the coolant

passages, install a water
(Especially with water-cooled filter, and increase the
packing.) supply pressure or rate.
Reduce the coolant
temperature atinlet.
4. Inadequate side 4. Replace the packing rings.

clearance.
HIGH DISCHARGE 1. Excessive ratio across the 1. Replace leaking inlet valves
TEMPERATURE cylinder. Rings leaking on or piston rings.
the next higher stage.
2. Fouled intercooler or 2. Clean intercooler or piping;

piping. reduce lube feed rate.
3. Leaking discharge valves 3. Repair/replace parts as

or piston rings. necessary.
4. High inlet gas 4. Clean intercooler; adjust

temperature. coolant flow/temperature
5. Fouled cylinder water 5. Clean water jackets.

jackets.
6. Improper cylinder lube oil 6. Use the proper type of oil

or lube feed rate. per the specifications in this
Instruction Manual; correct
the feed rate.
RELIEF VALVE 1. Faulty relief valve. 1. Test valve and reset per
POPPING manufacturer’s instructions.
2. Leaking inlet valves or piston 2. Repair/replace defective

rings on next higher stage. parts.
3. Obstruction, blind flange 3. Relieve obstruction; open

or valve closed in valve.
discharge line.
3-25
EXCESSIVE CARBON ON 1. Too much cylinder lube 1. Adjust the supply rate.
VALVES oil.
2. Wrong cylinder lube oil, 2. Use the proper type of oil for
too light; high carbon this application. See Table
residue. 2-4 in this Instruction
Manual.
3. Oil carryover from inlet or 3. Install separator/drain

previous stage. system.
4. Broken or leaking valves; 4. Replace or repair valves.

high temperature.
5. Excessive pressure ratio 5. Clean intercoolers; valves.

across cylinder, high Look for failed valve in
temperature. cylinder, upstream or down-
stream.
3-26
Table 3-2. Valve Troubleshooting Chart
TROUBLE REASON OR ACTION TO BE TAKEN
VALVE FAILURE – INLET VALVES 1. Make certain that the correct parts are being
used. In many cases, inlet springs are lighter
than discharge springs.
2. Investigate the possibility of liquid carryover.
3. Consider the possibility of intake pulsations.
4. Flutter – Incorrect spring action.
VALVE FAILURE – DISCHARGE 1. Make certain that the correct parts are being used.
VALVES In many cases, discharge springs are stiffer than
inlet springs.
2. Check the log of failures to see if the failures occur

only when a clearance pocket is open. If this is the
case, report the situation to Dresser-Rand.
3. Consider the possibility of discharge pulsations.
VALVE FAILURE – BOTH INLET 1. Make certain that the correct parts are installed.
AND DISCHARGE
2. Check to see if the discharge failures are caused by
broken pieces of other valves.
3. Check for rust, scale or other foreign matter.
4. Check for excessive wear of parts caused by grit or

insufficient lubrication.
5. Consider the possibility of pulsations.
6. Stiction – Incorrect lube rate or varnish.
FAILURE FOLLOWING 1. Check the reconditioning procedures to make sure

RECONDITIONING that the valve lift was not changed.
2. Verify that the correct parts were installed.
SEASONAL FAILURES 1. Winter failures caused by liquid slugs.

A. Piping should be insulated.
B. Piping should be steam traced.
C. Separators should be installed.
3-27
Table 3-2. Valve Troubleshooting Chart Continued
TROUBLE REASON OR ACTION TO BE TAKEN
RAPID WEAR – 1. Insufficient lubrication rate or the incorrect cylinder

INLET VALVES ONLY lube oil.
2. Wet gas washing the lubrication from the valves.
3. Cylinder water temperature lower than the incoming

gas temperature.
4. Dirty process gas; install scrubbers.
RAPID WEAR – 1. Insufficient lubrication rate or the incorrect cylinder

DISCHARGE VALVES ONLY lube oil.
2. Dirty process gas; install scrubbers.
3. Flutter – Incorrect spring selection.
BROKEN SPRINGS 1. Investigate the possibility of gas contaminants

causing corrosion. Send samples of the broken
parts to Dresser-Rand.
2. Check for grit or other solid matter, which can lodge

between the coils of the compression springs to
cause failure.
3. Stiction – Incorrect lube rate or varnish.
BROKEN PLATES 1. Check the valve plates for wear resulting in sharp
(BUT NOT SPRINGS) corners at O.D. or I.D.
3-28
Form PG-4875-C
DRESSER-RAND MAINTENANCE
HOSS
CHAPTER 4
Paragraph Page

4-2. SAFETY PRECAUTIONS ................................................................................. 4-4
4-3. ACCESSORY EQUIPMENT ............................................................................. 4-5
4-4. FRAME ............................................................................................................. 4-5
4-5. MAIN BEARINGS .............................................................................................. 4-7
4-5.1. Checking Main Bearing Clearance .............................................................. 4-8
4-5.2. Replacing a Main Bearing ........................................................................... 4-8
4-5.3. Bearing Crush ............................................................................................. 4-10
4-6. CRANKSHAFT .................................................................................................. 4-10
4-6.1. Checking Crankshaft Thrust ........................................................................ 4-11
4-7. CRANKSHAFT OIL SEAL ................................................................................. 4-12
4-8. CONNECTING RODS ....................................................................................... 4-13
4-8.1. Checking Connecting Rod Bearing Clearance ............................................ 4-14
4-8.2. Replacing a Connecting Rod Bearing ......................................................... 4-15
4-8.3. Replacing a Small End Bushing .................................................................. 4-17
4-8.4. Removing the Connecting Rod ................................................................... 4-18
4-8.5. Installing the Connecting Rod ..................................................................... 4-20
4-8.6. Connecting Rod Bolt Stretch Micrometer Procedure .................................. 4-21
4-9. CROSSHEADS ................................................................................................. 4-23
4-9.1. Removing the Crosshead ............................................................................ 4-24
4-9.2. Installing the Crosshead .............................................................................. 4-26
4-10. CROSSHEAD SHOES ...................................................................................... 4-28
4-10.1. Crosshead Shoe Replacement ................................................................... 4-28
4-10.2. Piston Rod Runout Adjustment ................................................................... 4-31
Table 4-1. Normal Cold Vertical Piston Rod Runout ...................... 4-32
4-11. COMPRESSOR CYLINDERS ........................................................................... 4-34
4-11.1. Removing the Compressor Cylinder .......................................................... 4-36
4-11.2. Installing the Compressor Cylinder ............................................................. 4-37
4-12. PISTON AND PISTON RODS ........................................................................... 4-39
4-12.1. Removing the Piston Rod ............................................................................ 4-39
4-12.2. Piston and Rod Disassembly – Cast/Nodular Iron Pistons ......................... 4-41
4-12.3. Piston and Rod Assembly – Cast/Nodular Iron Pistons .............................. 4-43
4-12.4. Piston and Rod Disassembly – Aluminum Pistons ...................................... 4-45
4-12.5. Piston and Rod Assembly – Aluminum Pistons .......................................... 4-45
Graph 4-1. Piston Nut Tightening Angle .......................................... 4-47
4-13. INSTALLING THE PISTON ROD and ADJUSTING END CLEARANCE .......... 4-49
4-14. INSPECTION / MAINTENANCE of CYLINDER BORES.................................. 4-51
Table 4-2. Cylinder Reconditioning Data ......................................... 4-52
4-14.1 Honing ......................................................................................................... 4-53
4-15. NON-METALLIC COMBINATION PISTON & RIDER RINGS ........................... 4-53
4-15.1. Handling Instructions ................................................................................... 4-53
4-15.2. Establishing Ring Wear Rate ...................................................................... 4-54
4-15.3. Replacing Rings .......................................................................................... 4-55
4-15.4. Installing Rings ............................................................................................ 4-55
Table 4-3. Piston and Ring Clearance for Standard Cylinders ........ 4-56
4-1
Maintenance PG-4875-C (HOSS)
Paragraph Page
4-15.5. Breaking-in Combination Rings ................................................................... 4-58

4-16. PISTON ROD PRESSURE PACKING .............................................................. 4-58
4-16.1. Packing Rings ............................................................................................. 4-59
Table 4-4. Packing Clearances ....................................................... 4-62
4-16.2. Packing Gasket ........................................................................................... 4-62
4-16.3. Packing Cases ............................................................................................ 4-62
4-16.4. Installing the Packing .................................................................................. 4-62
4-16.5. Packing Operation and Maintenance .......................................................... 4-65
4-16.6. Inspecting the Packing ................................................................................ 4-65
4-16.7. Replacing the Packing................................................................................. 4-65
4-17. PISTON ROD OIL SCRAPER RINGS .............................................................. 4-66
4-18. BALANCE CYLINDER (If Used)........................................................................ 4-68
4-19. COMPRESSOR VALVES ................................................................................. 4-69
4-19.1. Description of Operation.............................................................................. 4-70
4-19.2. Valve Maintenance Recommendations ....................................................... 4-70
4-19.3. Removing the Valves – O-Ring Valve Cover............................................... 4-72
4-19.4. Disassembling and Servicing the Valve ...................................................... 4-75
4-19.5. Reconditioning the Valve Seat .................................................................... 4-77
4-19.6. Reconditioning the Stopplate ...................................................................... 4-78
4-19.7. Assembling the Valve .................................................................................. 4-79
4-19.8. Installing the Valves – O-Ring Valve Cover ................................................ 4-80
4-20. REGULATION DEVICES .................................................................................. 4-83
4-20.1. Unloaders – Inlet Valve and Clearance Pocket ........................................... 4-83
A. Control and Vent Piping Considerations .......................................... 4-88
B. Unloader Cleanliness ...................................................................... 4-89
C. Removing the Operator, Unloader and Valve Assembly ................. 4-90
D. Disassembling the Operator – Air-to-Load (Direct-Acting) .............. 4-91
E. Disassembling the Operator – Air-to-Unload (Reverse-Acting) ....... 4-92
F. Disassembling the Indicator ............................................................ 4-92
G. Disassembling the Unloader Guide ................................................. 4-93
H. Servicing the Packing Gland ........................................................... 4-94
I. Reassembling the Unloader Guide .................................................. 4-95
J. Reassembling the Indicator ............................................................. 4-95
K. Reassembling the Operator – Air-to-Load (Direct-Acting) ............... 4-96
L. Reassembling the Operator – Air-to-Unload (Reverse-Acting)........ 4-96
M. Installing the Operator – Air-to-Load (Direct-Acting) ....................... 4-97
N. Installing the Operator – Air-to-Unload (Reverse-Acting) ................ 4-98
4-20.2. Variable Volume Clearance Pockets ........................................................... 4-99
Table 4-5. Maximum Allowable Clearance Volume ......................... 4-103
A. Removal/Disassembly of the One-Piece Style Outer Head............. 4-103
B. Assembly/Installation of the One-Piece Style Outer Head .............. 4-105
C. Removal/Disassembly of the Two-Piece Style Outer Head............. 4-106
D. Assembly/Installation of the Two-Piece Style Outer Head .............. 4-108
E. Removal/Disassembly of the Plug Type VVCP ............................... 4-109
F. Assembly/Installation of the Plug Type VVCP ................................. 4-110
4-2
PG-4875-C (HOSS) Maintenance
This section describes the recommended procedures for disassembling, servicing or

replacement, and reassembling of the compressor running gear and cylinders. Service notes
have been placed in the text to assist the mechanic. Separate instructions are furnished to
cover special or optional equipment.
Good working habits are essential to the performance of satisfactory maintenance work
on the compressor. When disassembling a unit, use every available means to keep dirt away
from the compressor internals. Cover exposed openings with cloth, Kraft paper, cardboard or
other suitable material to keep dirt from falling into the frame interior or into the compressor
cylinders. Scratches, nicks and rough areas must be removed from machined surfaces. This
can be done with fine emery cloth, a fine hone or a mill file. (Do not use emery cloth, or any
other finishing method employing abrasives, when working on soft bearing surfaces; such
material can become embedded in the bearing metal.)
Mark or tag parts as they are disassembled so that they can be replaced in their original
positions. Replace all composition gaskets that are torn, dried or cracked with ones of similar
material and thickness. Shims should be marked so that they will be reassembled in their
original positions or so that replacement shims can be accurately sized.

Original parts should be thoroughly cleaned in a solvent compatible to the process and
to the material of the parts to be cleaned. Inspect the parts for wear and other visible defects
before re-using them. Generally, unless otherwise stated, the running surface of the parts
should be covered with a thin coating of clean lubricant before reassembling.
After removal, all cotter pins, lockwashers, lock wires and other locking devices must be
replaced to prevent the loosening of parts during operation. Always advance a nut in the
tightening direction to align cotter pin openings once the required torque or bolt stretch is
obtained. Lockwire must always be arranged so that it pulls on the bolt head in the tightening
direction.
Running gear clearances and fits and joint tightening requirements are summarized at
the back of this Instruction Manual in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS.
The specified clearance limits and fits are those to which the parts are originally assembled.
Unless otherwise stated, they are for parts that are at room temperature and are generally
referred to as "cold" clearances. Some slight changes in clearance can be expected when the
parts are hot.
Generally, the clearances and fits listed should be checked during maintenance work
involving those parts. It is recommended that the running clearances be checked with the parts
in their assembled positions, wherever possible, since bearing crush, interference fits and other
factors can affect the clearance measurement.
4-3
Logging the listed clearances can be of considerable help in determining the wear of the
parts. It can also be a benefit in estimating the time interval between scheduled overhauls.
Varying operating conditions at different installations make it impractical to specify

maximum acceptable clearances. Careful observation of the unit by the operator and good
judgment by the mechanic are often the most effective means of determining when clearances
have become excessive and the adjustment/replacement of parts is required.
4-2. SAFETY PRECAUTIONS
Observe every safety precaution when working on the compressor frame, cylinders and
drive arrangement, especially when making repairs or adjustments inside of the frame or
cylinders. The following precautions should be taken before working on the compressor.
1. Service on a machine should always start with cleaning the floor and the outside of the
machinery to remove oil that could cause maintenance personnel to slip and be injured.
2. Compressors handling toxic or flammable gases must be isolated from the process
piping by means of blinds, or double valves and bleed valves, when major maintenance
is required. Before opening such compressors, the equipment must be purged or
evacuated. Minor adjustments may be performed without blinding provided that
adequate precautions, such as de-pressurizing the system, are taken to protect
personnel. Check valves must not be relied upon for isolating the compressor.
3. For non-hazardous gases, close both the suction and discharge line valves and bleed
off any pressure that may be in the compressor cylinders.
4. Never open a compressor cylinder or any other part of the compression system without
again verifying that all of the gas pressure within the unit has been relieved. Take all
the necessary precautions to prevent the accidental re-pressurizing of the system.
5. Be certain the main driver is locked out so that there is no possibility of the driver being
started. In addition, a warning sign bearing the legend "WORK IN PROGRESS - DO
NOT START" must be attached to the starting equipment.
6. Block or brace under a crankshaft web, or block the crossheads, so that the crankshaft
cannot turn while working inside the unit.

7. Consult OSHA regulations covering cleaning materials and their use. Volatile
flammable liquids must not be used as cleaning agents for engine or compressor parts.
A safety solvent should be used and the parts dried thoroughly before assembly.
CARBON TETRACHLORIDE MUST NEVER BE USED AS A CLEANING SOLVENT.
Appropriate provisions for ventilation should be made when using other halogenated
solvents.
4-4
8. Compressor manufacturers utilize elastomer seals (O-rings) found in today’s

compressor frames, distance pieces (yokes), compressor cylinders and valves. When
selecting O-rings the process conditions must be thoroughly understood. At high
pressure and high mole weight gas applications, gases can diffuse into the O-ring.
Upon rapid blowdown or decompression, the impregnated gas may exit too quickly
causing the O-ring to “blister”, thus leading to process gas leakage upon re-start. For
high-pressure and high mole weight gas applications, O-ring material selection, O-ring
hardness (durometer generally 85 – 90) and decreased blowdown rate (psi / min.) have
alleviated problems with leakage due to “blistering”. Dresser-Rand Co. can provide
guidance for O-ring or seal selection to reduce the possibility of O-ring leakage due to
“blistering”.
4-3. ACCESSORY EQUIPMENT
Items not manufactured by Dresser-Rand Company include the lubricator, oil cooler,
drive engine or motor, coupling, filters, coolers, scrubbers and control devices. Additional
equipment supplied by the packager of the compressor must be supported by accessory
literature supplied by the various manufacturers of the components. This literature, generally
including engine or drive motor manufacturer's bulletins, coupling manufacturer's bulletins and
control panel manuals, should be found in the overall manual prepared by the packager for the
complete compressor package.
4-4. FRAME
1. The compressor frame (Figures 4-1, 4-2 and 4-3) is a rigid; cast iron structure designed
to provide a suitable mounting for compressor cylinders, crankshaft and other running
gear, and to hold all parts in accurate alignment under the stresses and strains involved
in operation. Suitable ribs and partitions are incorporated in the frame design to provide
the maximum strength compatible with reasonable weight.
2. The lower part of the frame forms a sump for the lubricating oil, and a pipe tap
connection is located on the oil pump end of the frame at the bottom of the oil sump to
permit sump draining. An oil level gauge is also located on the side of the frame at the
oil pump end so that the frame oil level can be checked at all times.
3. The frame contains the main bearings, crankshaft, connecting rods and crossheads,
which comprise the "running gear".
4. The only maintenance required on the frame are to check the tightness of all the fittings
and joints following the procedures as described in CHAPTER 5, GENERAL DATA AND
SPECIFICATIONS, Section 5-3 of this Instruction Manual.
4-5
TP-5108
Figure 4-1. Typical Two Throw HOSS Frame
TP-5109
Figure 4-2. Typical Four Throw HOSS Frame

4-6
TP-5110
Figure 4-3. Typical Six Throw HOSS Frame
4-5. MAIN BEARINGS
The main bearing arrangement is shown in Figure 4-4. The main bearings are
horizontally split precision steel backed bronze shells that are accurately sized to fit the bearing
caps and the support saddles in the frame.
Main Bearing Tie Rod Spacer
Main Bearing Cap
Main Bearing
Cap Stud/Nuts
Main Bearing Shell

A Thrust Bearing
Main Bearing
Oil Header
TP-5111
Figure 4-4. Main Bearing Arrangement

4-7
Whenever a main bearing cap is removed from the machine, it is important that it is
returned to its original position in the frame or serious damage can result. The bearing caps are
match-stamped in an off center location to agree with the nearest stamping on the top of the
frame partition. Always check the stamping on a bearing cap when installing it to be sure that it
matches the nearest stamping on the frame partition.
4-5.1. Checking Main Bearing Clearance
Be certain the main driver is blocked out so that there is no

possibility of the driver starting. In addition, a warning sign
bearing the legend "WORK IN PROGRESS - DO NOT START"
must be attached to the starting equipment.
The clearance of each main bearing can be determined by the use of Plastigage® at
point "A" shown in Figure 4-4. Follow the recommended Steps in Paragraph 4-5.2 for the
proper procedure for the removal of the tie rod spacer and the main bearing cap. Lay a piece of
Plastigage® across the crankshaft journal, then install the main bearing cap and torque the nuts
to the proper specifications. Remove the cap and measure the Plastigage® to ensure you have
the proper clearance. Refer to CHAPTER 5, GENERAL DATA AND SPECIFICATIONS
Paragraph 5-2 in this Instruction Manual, which gives the bearing clearance limits as originally
built. Remove the Plastigage® from the crankshaft and/or bearing before reassembly. These
clearance limits, although only guidelines, can be helpful in determining when a bearing
requires replacement. The only proper way to determine if a bearing replacement is required is
to perform a visual check. It should be noted, however, that a bearing will give much longer
service when the proper oil clearance is maintained. After a bearing change always recheck the
actual bearing-to-shaft clearance with Plastigage® before operating the machine.
Plastigage® is the preferred method of checking bearing clearances. If Plastigage® is

not available, another acceptable method is doing a lift check.
Mount a dial indicator on top of the main bearing cap with the indicator touching as close
to the top center of the crankshaft as possible. Lift the crankshaft up until the clearance is
removed, and note the dial indicator reading. Ensure that the crankshaft does not rotate while
checking bearing clearances using the lift check method.
4-5.2. Replacing a Main Bearing
If replacement of a main bearing becomes necessary, follow these recommended Steps:

4-8
1. Remove all of the top covers from the frame.
2. Loosen all of the frame spacer tie rods.
3. Install two 0.500-13UNC eyebolts, one in each end of the frame spacer that
corresponds to the bearing being serviced. Carefully remove the frame spacer using an
overhead hoist of sufficient capacity while tapping it lightly on the bottom with a soft
bronze hammer due to the interference fit. Then remove the tie rod.
4. Remove the hex nuts and locking tabs from the studs on each side of the main bearing
cap.
5. Install a 0.500-13UNC eyebolt into the tapped hole in the top of the bearing cap
corresponding to the bearing being serviced. Carefully remove the bearing cap and
upper bearing half again using an overhead hoist of sufficient capacity while tapping it
lightly with a soft bronze hammer due to the interference fit.
SERVICE NOTE
If more than one adjacent lower shell is removed; blocking must be

used to support the crankshaft. Always support the crankshaft on
two throw frames.
6. Remove the lower half of the bearing by rotating it 180 in the direction of the bearing
tang (the bearing tang must come out first). If the lower shell cannot be pushed out by
hand, use a copper or soft metal "roll-out" plug in the crankshaft and "roll out" the lower
shell. The plug is placed in the oil hole in the crankshaft so that it protrudes about
1/8-inch (3.2 mm) from the shaft; it must be flanged to prevent it from dropping into the
oil hole.
Never scrape the bore nor file or attempt to build up the ends
of these precision bearing shells. To do so will result in a
ruined bearing and possible major damage to the crankshaft.
7. Clean the replacement bearing shells, being certain that the oil holes and grooves are
clear, and also clean the bore in the frame and cap before assembling the new bearing.
It is essential that there be no dirt or foreign particles between the bearing shells and the
bore, and that the shells fit their housing perfectly so that they are supported uniformly
at all points. An imperfect fit, burrs, nicks or dirt between the shells and support saddle
or cap will result in a stress concentration due to the flexing of the shell and subsequent
premature failure of the bearing. It is normally not required to check bearing crush since
these are precision made and inspected parts. If a bearing crush problem is suspected,
contact your Dresser-Rand service representative.
4-9
8. Lubricate and install the lower half of the bearing by rotating it 180 leading with the
plain end until the bearing tab is flush with the top of the bearing saddle. Also lubricate
and install the top half of the bearing into the main bearing cap making sure that the
tang on the bearing is located in the slot in the cap.
9. Install the main bearing cap and locking tabs, being careful to correctly orient the cap
into the frame and tighten the hex nuts evenly to the torque value specified in
CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-3.8 in this
Instruction Manual.
10. Check the installed bearing clearance with Plastigage® as described in Paragraph 4-5.1
before continuing with any further assembly. As a final step, bend one of the tabs up at
each hex nut on the main bearing cap(s) locking the nuts in place.
11. When one or more replacement bearings are installed, check the crankshaft alignment
by checking for clearance under the bottom of the crankshaft journal at each main
bearing. A 0.0015 inch (0.04 mm) feeler should not start. Any bearings found to be low
must be replaced.
12. Replace the main bearing tie rod and spacer, using Teflon® pipe thread sealer under the
nut heads and washers, and on the tie rod threads. Gently tap in the spacer as it is
sized for an interference fit with the frame opening. Position the tie rod in the frame so
that it is centered with respect to the frame. Place a washer over each end of the tie rod
and then assemble and snug up the cap nuts evenly. Tighten one of the nuts until the
measured distance in the spacer opening is within 0.001-inch (0.03-mm) of the
dimension stamped in the frame adjacent to the spacer. Retighten all of the other
spacers following the same procedure.
13. Check to make sure no tools have been left inside the frame and install the frame top
covers and any other parts that may have been removed.
4-5.3. Bearing Crush
Bearing crush is the difference in height between the bearing and its housing at the
parting line. This crush is actually an interference fit between the bearing and its housing. It is
necessary to assure full contact between the bearing and housing to prevent flexing of the
bearing shell and to aid in transferring heat from the bearing. Because both bearings and
housings are precision made parts; there is no reason to measure the bearing crush in the field.
If a problem with bearing crush is suspected, contact your Dresser-Rand customer service
NOTE
Bearing crush has no relation to bearing clearance and it is

important that the two are not confused.
4-6. CRANKSHAFT
The crankshaft is a single-piece, heavy steel forging and is designed to avoid torsional
criticals within the operating speed range of the unit. There is a separate crank throw to carry
4-10
the connecting rod for each compressor cylinder. Both two and four throw crankshafts have
shrunk-on counterweights to reduce horizontal forces and moments.
Oil holes are drilled in the shaft from the main journals to the adjacent crank pins so that
lubricating oil under pressure at the main bearings is fed to the connecting rod bearings. It is
essential to the proper lubrication of the compressor that the oil passages in the crankshaft are
kept clear of any obstruction. They should be inspected during any compressor overhaul for
sludge or other obstructions.
4-6.1. Checking Crankshaft Thrust
Bronze thrust shoes are fastened to the inboard faces of the two main bearing caps at
the drive end of the frame. The shoes bear against the raised crankshaft journal collars and
limit the end thrust of the crankshaft. Refer to Figure 4-5.
TP-5112
Figure 4-5. Crankshaft Thrust Arrangement
Crankshaft end thrust, or endplay, is totally controlled by the position of the driver unit,
whether it is a motor or a gas engine. The thrust shoes cannot in any way "control" the end
thrust and the shoes are installed primarily to position only the compressor crankshaft axially in
the frame. Normally, end thrust is negligible if the compressor and driver have been properly
installed.
If wear on the thrust surfaces is observed, the only way to

correct it is moving the driver. If this isn't done, serious
damage to the compressor crankshaft or frame will result.
4-11

The compressor is originally built with a total crankshaft thrust clearance within the limits
given in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-2 in this
Instruction Manual. The clearance can be measured by totaling the feeler clearances taken
between each thrust shoe and the adjacent crankshaft journal collar (see Figure 4-5).
Adjustment of the crankshaft axial thrust clearance requires loosening the hex nuts on top of
one thrust bearing cap and sliding the main bearing cap to adjust the axial clearance.
4-7. CRANKSHAFT OIL SEAL
The crankshaft oil seal (#7) is located in the drive end cover (#1) as shown in Figure 4-6.
A correctly installed oil seal should require little or no attention.
TP-5113
Figure 4-6. Crankshaft Oil Seal
4-12
Should leakage occur past the crankshaft oil seal, do not,

under any circumstances, reduce the bearing oil pressure in an
effort to control the leakage. Reduced oil pressure can result
in serious compressor damage, which might not be
immediately apparent.
The following procedure is recommended to properly replace the crankshaft oil seal:

1. Remove the eight capscrews (#9) that fasten the seal retainer halves (#8) to the drive
end cover (#1), then remove the two seal retainer halves.
2. Pry out the worn oil seal (#7) out of the drive end cover counterbore. Clean the seal
counterbore in the drive end cover, along with the crankshaft.
3. Coat the oil seal (#7) with heavy oil or grease on only that portion that contacts the
crankshaft. Orient the seal so that the seal lips are pointing toward the frame and then
press the seal into the recess in the drive end cover with the split at the 12:00 o’clock
position. The oil seal ends can be glued together using one of these three adhesives:
Eastman® 910, Loctite® Quikset 404 or Chemosil® 100.
4. Install the seal retainer halves (#8). Apply a light coat of Loctite® 242 Threadlocker to
the threads of the eight capscrews (#9) and then install and tighten securely being
careful no to distort the seal retainers (#8).
4-8. CONNECTING RODS
The compressor connecting rod (see Figure 4-7) is made of forged steel and
incorporates a one-piece, shrink-fitted bronze bushing (#4), with a thin babbitted coating on the
bore only, in the small end. Precision steel backed bronze bearing shells (#5) in the large
(crankpin) end are accurately sized to fit the cap and rod. The rod is rifle drilled from the
connecting rod journal bearing-end to the crosshead pin-end, providing a passageway for the
lubricating oil between the two points. Dowel pins (#3) between the cap and the shank of the
connecting rod maintains the bearing alignment.
Whenever the connecting rod cap is removed from the rod, it must be reassembled in
exactly the same position it held during factory assembly or serious damage to the unit can
result. The cap and its rod are match-stamped with identical letter and number markings as
4-13
shown in Figure 4-7. Always check the stamping on the cap when installing it to be sure it
matches the stamping on the rod.
TP-5114
Figure 4-7. Connecting Rod Assembly
4-8.1. Checking Connecting Rod Bearing Clearance

The clearance between the connecting rod bearing and crankpin can be determined by
the use of Plastigage®. Follow the recommended Steps in Paragraph 4-8.2 for the
recommended procedure for the removal of the connecting rod cap. Lay a piece of Plastigage®
across the crankshaft crankpin, then install the connecting rod cap using the connecting rod bolt
stretch tightening procedure (see Paragraph 4-8.6). Remove the cap and measure the
Plastigage® to ensure you have the proper clearance. Refer to CHAPTER 5, GENERAL DATA
AND SPECIFICATIONS Paragraph 5-2 in this Instruction Manual, which gives the bearing
clearance limits as originally built. Remove the Plastigage® from the crankshaft and/or bearing
before reassembly. These clearance limits, although only guidelines, can be helpful in
determining when a bearing requires replacement. The only proper way to determine if a
bearing replacement is required is to perform a visual check. It should be noted, however, that
a bearing will give much longer service when the proper oil clearance is maintained. After a
4-14
bearing change always recheck the actual bearing-to-shaft clearance with Plastigage® before
operating the machine.
Plastigage® is the preferred method of checking bearing clearances. If Plastigage® is

not available, another acceptable method is doing a lift check.
Mount a dial indicator on top of the connecting rod with the indicator touching as close to
the top center of the crankshaft as possible. Lift the connecting rod up until the clearance is
removed, and note the dial indicator reading. Ensure that the crankshaft does not rotate while
checking bearing clearances using the lift check method.
4-8.2. Replacing a Connecting Rod Bearing
If replacement of a connecting rod bearing becomes necessary, follow these

recommended Steps:

1. Remove the frame top cover that will give access to the connecting rod bearing being
replaced.

The operator must ensure that the driver will not start either by
grounding the ignition and closing the fuel gas valve on gas
engine-driven units or by ensuring that power cannot be turned
on with electric motor-driven units, before barring the unit
over. Failure to heed this WARNING can result in a fatal
accident if the unit rolls over unexpectedly.
4-15
2. Rotate the crankshaft to place the connecting rod in a convenient position to remove the
connecting rod cap.
3. First remove the wire ties (#6) then remove the connecting rod bolts (#2). Refer to
Figure 4-7.
4. Using an overhead hoist of sufficient capacity and a 0.375-16UNC eyebolt with a sling,
carefully lift the connecting rod cap and bearing shell half out of the frame.
5. Support the connecting rod and then rotate the crankshaft to move the crankpin away
from the rod so that the rod bearing shell half can be removed.
Never scrape the bore nor file or attempt to build up the ends
of these precision bearing shells. To do so will result in a
ruined bearing and possible major damage to the crankshaft.
6. Clean the replacement bearing shells, being certain that the oil holes and grooves are
clear, and also clean the bore in the connecting rod and cap before assembling the new
bearing. It is essential that there be no dirt or foreign particles between the bearing
shells and the rod, and that the shells fit their housing perfectly so that they are
supported uniformly at all points. An imperfect fit, burrs, nicks or dirt between the shells
and support saddle or cap will result in a stress concentration due to the flexing of the
shell and subsequent premature failure of the bearing. It is normally not required to
check bearing crush since these are precision made and inspected parts. If a bearing
crush problem is suspected, contact your Dresser-Rand service representative.
7. Lubricate and install the bearing shell halves in the rod and cap. Each shell half has a
tab on its outer edge at the parting line. The tabs fit into slots which are machined into
the rod and cap and accurately position each shell half and lock the bearings to prevent
rotation in the bore.
8. Assemble the rod and cap on the crankpin. Work carefully to correctly orient the cap
checking the match markings and to prevent damaging the parts.
9. Tighten the connecting rod bolts (#2) in the connecting rod uniformly until the bolts are
elongated (stretched) the amount given in CHAPTER 5, GENERAL DATA AND
SPECIFICATIONS Paragraph 5-3.8 in this Instruction Manual. Bolt elongation is
determined by measuring the length of the bolt both before and after tightening. (See
Paragraph 4-8.6).
10. Check the bearing to crankpin clearance using Plastigage® as described in Paragraph
4-8.1. After checking clearance, verify that all the connecting rod bolts (#2) are properly
stretched, then wire tie them together (#6) remembering to position the wire so that it
pulls on the bolt head in the tightening direction.
11. Check to be sure no tools have been left inside the frame and replace the top cover on
the frame.
4-16
4-8.3. Replacing a Small End Bushing
The crosshead pin bushing (#4) is an interference fit bushing housed in the small end
(eye) of the connecting rod. Refer to Figure 4-7. See Paragraph 4-8.4 for the recommended
procedure to remove the connecting rod if it is necessary to replace the crosshead pin bushing.
Comparing the micrometer measurements between the pin O.D. and bushing I.D can
check the small end bushing-to-crosshead pin clearance. The bushing is non-adjustable; it
must be replaced with a new one when the clearance becomes excessive or if the bushing is
otherwise defective. Reduced oil pressure and noise from the crosshead pin area are
indications that bearing clearances have become excessive.
If replacement of a connecting rod bushing becomes necessary, follow these

recommended Steps:
1. Press or machine the old bushing out of the connecting rod. If a machining operation is
used, be careful not to cut into the connecting rod.
2. Clean the rod and check to make sure it is not bent or twisted. Maximum allowable
bend and/or twist is 0.003 inch (0.076 mm).
Always use liquid nitrogen in a well-ventilated area and protect

the eyes and skin from contact. Improper use may result in
frostbite, respiratory ailments or asphyxia.
3. The back of the bushing and connecting rod eye must be wiped clean before installing
the bushing. The replacement bushing must be chilled (using liquid nitrogen) to reduce
its outer dimension sufficiently so that it can be pressed into the eye of the connecting
rod without applying an appreciable amount of force.
4. Use an insertion tool as shown in Figure 4-8 to guide the chilled bushing into the rod.
The tool will aid in keeping the bushing square as it enters the rod. Do not allow the
bushing to warm up during this procedure. Excessive force on these thin-walled
bushings will cause distortion.
SERVICE NOTE
The bushing should project 0.125 inches (3.2 mm) equally on each
side of the connecting rod. (See Figure 4-7.)
There is a hole in the connecting rod bushing, which must

align with the rifle-drilled hole in the rod to ensure sufficient
lubrication of the crosshead. If the hole is not aligned
properly, the crosshead bushing will be quickly destroyed.
4-17
TP-5115
Figure 4-8. Bushing Insertion Tool
5. Make sure the oil hole in the bearing is lined up with the oil hole in the connecting rod.
Secure the bushing in place until it reaches ambient temperature to prevent it from
moving.
6. After the bushing has reached ambient temperature, measure the bushing I.D. which
should be 5.016 - 5.013 inches (127.41 – 127.33 mm). Then measure the pin-to-
bushing diametrical clearance and compare it to the value specified in CHAPTER 5,
GENERAL DATA AND SPECIFICATIONS Paragraph 5-2 in this Instruction Book for
assembly fits and clearances. If the clearance is not correct, investigate the cause and
take corrective action.
4-8.4. Removing the Connecting Rod

1. Remove the top frame cover and frame extension covers that will give access to the
connecting rod being removed.
4-18

2. Bar the compressor over until the cylinder is at mid-stroke and the connecting rod being
worked on is positioned at the top of the frame. First remove the wire ties (#6) then
break the connecting rod bolts (#2) loose – DO NOT REMOVE. Refer to Figure 4-7.
3. Continue to bar the compressor over until the cylinder is at top-dead-center. Remove
the lockwire (#8) and capscrews (#5) that fasten the pin end caps (#4) to the crosshead
pin (#2) then remove the crosshead pin caps. Refer to Figure 4-10.
4. Place a protective cover over the crosshead guide surface to prevent damage when the
connecting rod is pulled out if the crosshead. Attach suitable lifting tackle to facilitate
pulling the pin (#2). At the same time, support the pin end of the connecting rod to take
the weight off of the crosshead pin, then slide the pin (#2) out of the crosshead.
5. Inspect the condition of the pin for excessive wear or damage; repair or replace if
required. If damaged, contact Dresser-Rand for technical advice or analysis.
6. Separate the connecting rod from the crosshead by slowly continuing to bar the
compressor over carefully withdrawing the connecting rod from the crosshead. Stop
barring when the connecting rod cap is at the top of the frame being careful not to
damage the crosshead guide.
7. Support the connecting rod from falling when the cap is removed. Remove the
connecting rod bolts.
8. Using an overhead hoist of sufficient capacity and a 0.375-16UNC eyebolt with a sling,
carefully remove the connecting rod cap and both bearing halves out of the frame.
9. Again using 0.375-16UNC eyebolts and a sling, carefully start to lift the connecting rod
out of the frame. Move the connecting rod and crankshaft as required to gain space for
removing the rod. Ease the large end of the connecting rod past the crankshaft.
Continue to rotate the crankshaft until the webs are positioned such that the small end
of the connecting rod will pass, using care to prevent damage to any of the components.
4-19
4-8.5. Installing the Connecting Rod

connecting rod is placed down into the crosshead.
SERVICE NOTE
Be sure the rifle-drilled oil passage in the rod is clear of any

obstruction before installing the rod. Also check the wrist pin
bushing clearance. Replace the busing if the clearance is
excessive or if the bushing is otherwise defective.

2. Using an overhead hoist of sufficient capacity and 0.375-16UNC eyebolts and a sling,
carefully lower the small end of the connecting rod shank past the webs of the
crankshaft rotating the crankshaft to allow for clearance. Continue lowering the small
end of the connecting rod until it enters the crosshead and the large end of the
connecting rod passes the crankshaft crankpin while rotating the crankshaft to provide
clearance. Use care to prevent damage to any of the components.
4-20
3. Rotate the crankshaft so that the crankpin is positioned at the top of the frame.
Lubricate and insert the correct bearing shell half into the shank portion of the
connecting rod. Position the large end of the connecting rod so that the bearing shell
has engaged the crankpin while supporting the small end of the connecting rod. Work
carefully to assure correct assembly and to prevent damage to both the crosshead and
crosshead guide. Then support the connecting rod from falling.
4. Lubricate and insert the other bearing shell half in to the connecting rod cap. Again
using a 0.375-16UNC eyebolt with an overhead hoist of sufficient capacity and sling,
install the connecting rod cap and bearing onto the crankpin. Install the connecting rod
bolts (#2) and snug them up lightly. Refer to Figure 4-7.
5. Slowly rotate the crankshaft to top-dead-center position using blocking to support the
small end of the connecting rod and help guide it into the crosshead.
6. Referring to Figure 4-10, attach suitable lifting tackle to lift the crosshead pin (#2), then
lubricate and install the pin (#2). Install the crosshead pin caps (#4) and tighten the
capscrews (#5) to the torque value specified in CHAPTER 5, GENERAL DATA AND
SPECIFICATIONS Paragraph 5-3.8 in this Instruction Manual. Wire tie (#8) together the
bolts (#5) on each side remembering to position the wire so that it pulls on the bolt head
in the tightening direction.
7. Check the bearing to crankpin clearance using Plastigage® as described in Paragraph

4-8.1.
8. Referring to Figure 4-7, finally tighten the bolts (#2) in the connecting rod uniformly until
the bolts are elongated (stretched) the amount given in CHAPTER 5, GENERAL DATA
AND SPECIFICATIONS Paragraph 5-3.8. Bolt elongation is determined by measuring
the length of the bolt both before and after tightening. (See Paragraph 4-8.6.)
9. As a final check of proper connecting rod installation, it is suggested that the unit be
barred through one complete revolution while watching the connecting rod to see that it
runs true on the crankpin. Finally, wire tie the connecting rod bolts (#2) together
positioning the wire (#6) so that it pulls on the bolt head in the tightening direction.
10. Check to be sure no tools have been left inside the frame and replace the frame
extension covers, along with the frame top cover.
4-8.6. Connecting Rod Bolt Stretch Micrometer Procedure

1. Prior to assembly, thoroughly degrease with solvent and dry all contact surfaces of the
connecting rod, bolts and cap.
4-21
2. Thoroughly lubricate the bolt threads and the bolt head contact surface with a coating of
clean mineral oil before placing the bolt into the connecting rod and tightening.
3. Bolts should be prick (center) punched on each end, before assembly, to ensure that
the micrometer reading is taken in the same place before and after elongation.
4. The micrometer reading of the bolt length should be taken before the bolt is tightened
(see Figure 4-9). This dimension should be recorded for reference.
Starrett Micrometer
Connecting Rod Bolt
Knurled Nut
Knurled Head Screw

TP-5116
Figure 4-9. Stretch Micrometer
The connecting rod bolts must be kept tight at all times. If they
are allowed to loosen, broken bolts and considerable damage
will occur. If these connecting rod bolts have been allowed to
run in a loosened conditioned, as noted upon inspection, they
should be replaced to prevent future fatigue failure no matter
what their visual appearance. New bolts must be securely
tightened to the proper stretch value specified in CHAPTER 5,
GENERAL DATA AND SPECIFICATIONS.
5. Each bolt should be tightened in small increments (using a 12 point socket) in a cross
pattern until the micrometer reading indicates the bolt has been elongated (stretched)
the specified amount. For the proper stretch dimension, refer to CHAPTER 5
GENERAL DATA AND SPECIFICATIONS Paragraph 5-3.8 in this Instruction Manual.
6. As a reminder when the connecting rod assembly has been completed, make sure to
wire tie the connecting rod bolts together positioning the wire so that it pulls on the bolt
head in the tightening direction.
4-22
4-9. CROSSHEADS
TP-5117
Figure 4-10. Crosshead
The compressor crosshead (see Figure 4-10) is a box type with shim adjustable shoes
(#6) that can be adjusted by adding or removing shims (#9) to provide the proper running
clearance between the crosshead guide and crosshead. Shims (#9) can also be transferred
between the top and bottom shoes (#6) to adjust the vertical piston rod runout.
The crosshead pin (#2) is semi-floating and is secured in place by end plates (#4)
attached with bolts (#5). A dowel pin (#3) in one of the end plates (#4) prevents rotation of the
crosshead pin (#2) within the crosshead (#1). The compressor piston rod screws into the
crosshead (#1) and is secured by a crosshead lock nut. Normal running clearance of the
crosshead in the crosshead guide is specified in CHAPTER 5, GENERAL DATA AND
SPECIFICATIONS Paragraph 5-2 of this Instruction Manual.
Balance weights may be bolted onto the nose of the crosshead. These balance weights
are custom made, by total weight, for each compressor and cannot be intermixed with other
balance weights on this compressor or with those from any other unit. The part number and
weight of each balance weight is stamped on its outer face (the face towards the cylinder).
4-23
4-9.1. Removing the Crosshead
Before doing any maintenance work on the cylinders, closely observe the minimum
safety precautions as described previously in Paragraph 4-2.
Also, before servicing the cylinders, review the Cylinder Parts List illustrations thoroughly
to become familiar with the particular assemblies involved. There may be slight design
differences on a particular assembly that can require a modification to the recommended
maintenance procedures.
To protect personnel, it is imperative that all pressure be bled

from the cylinder passages before attempting to open the
cylinder.
1. Remove the outer head of the cylinder that corresponds to the crosshead being
removed.
2. Remove the frame top cover, frame extension covers and distance piece (yoke) covers
that will give access to the crosshead being removed.

3. If required, bar the compressor over until there is easy access to the crosshead balance
weight. Make sure to identify the location of the counterweight on the crosshead to
allow replacement back in the same location. Remove the lockwire and capscrews.
Sling the counterweight from an overhead hoist of sufficient capacity and/or block the
counterweight inside the frame extension to support the counterweight.
4-24
4. Bar the compressor over until the cylinder is at bottom-dead-center. Block the
crosshead by jamming wooden blocks between the crosshead and the frame extension
to prevent twisting of the crosshead and/or connecting rod when removing the
crosshead lock nut. Loosen the crosshead lock nut on the piston rod.
Never use a pipe wrench, or any other tool that can scratch or
otherwise damage the piston rod. Most pistons are drilled and
tapped which will allow a tee bar-type wrench (see Figure 4-11)
to be attached to the outer face of the piston to screw the
piston and rod assembly in or out of the crosshead. Where
this is not possible, a mechanical strap (parmalee) wrench is
recommended to turn the rod.
5. Unscrew the piston rod from the crosshead using a strap wrench or the piston rotation
tool as shown in Figure 4-11, until the piston rod thread disengages from the crosshead.
6. Pull the piston away from the crosshead being careful not to pull the threads into the
scraper rings. Unscrew the crosshead lock nut off of the piston rod. Finally, if required,
remove the crosshead balance weight.
7. Referring to Figure 4-10, bar the compressor over to top-dead-center being careful not
to jam the crosshead (#1) into the piston rod threads. Remove the lockwire (#8) and
capscrews (#5) that fasten the two pin end caps (#4) to the crosshead (#1) then remove
the crosshead pin caps.
connecting rod is pulled out of the crosshead. Attach suitable lifting tackle to facilitate
TP-5118
Figure 4-11. Piston Rotation Tool
4-25
9. Inspect the condition of the pin for excessive wear or damage; repair or replace it if
compressor over withdrawing the connecting rod from the crosshead. Stop baring when
the rod is at bottom-dead-center being careful not to damage the crosshead guide.
11. Rotate the crosshead 90° in the guide to place it on its side. Using 2 X 4 lumber to lift
and support the crosshead, carefully slide and then lift the crosshead out of the frame.
12. Immediately mark the crosshead to identify which cylinder it is associated with and
which crosshead shoe (#6) is positioned on top.
4-9.2. Installing the Crosshead
1. Using the appropriate micrometers, measure the I.D. of the crosshead guide and the
O.D of the crosshead shoes (#6) and verify that the running clearance matches the
value listed in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-2 in
this Instruction Manual. If not, continue to install the crosshead, then follow the
instructions in Paragraph 4-10.1 to adjust and correct the clearance problem.
2. Clean and lubricate both of the crosshead guide surfaces. Lift and install the crosshead
into the frame extension bore using 2 X 4 lumber to help support and not damage the
crosshead guide or crosshead shoe surfaces. Carefully rotate the crosshead 90°
making sure that the crosshead shoe (#6) previously marked is on top. See Figure 4-
10.

3. Slowly rotate the crankshaft toward top-dead-center position using blocking to support
the small end of the connecting rod and help guide it into the crosshead. Be careful not
to damage the crosshead guide surface.
4-26
4. Inspect the condition of the pin for excessive wear or damage; repair or replace it if
5. Referring to Figure 4-10, attach suitable lifting tackle to lift the crosshead pin (#2), then
lubricate and install the pin (#2). Install the crosshead pin caps (#4) and tighten the
capscrews (#5) to the torque value specified in CHAPTER 5, GENERAL DATA AND
SPECIFICATIONS Paragraph 5-3.8 in this Instruction Manual. Wire-tie (#8) together
the bolts (#5) on each side remembering to position the wire so that it pulls on the bolt
head in the tightening direction.
6. Bar the compressor over to bottom-dead-center in the direction that does not jam the
crosshead into the piston rod threads.
7. If required, verify that the crosshead counterweight is being put back into the correct
location. Sling the counterweight from an overhead hoist of sufficient capacity and
install the counterweight inside the nose of the frame extension. Use blocking to help
support the counterweight from falling.
8. Gently push the piston rod back (if required - through the counterweight) into the
cylinder stopping short of the crosshead to allow the crosshead lock nut to be installed.
Thread the crosshead lock nut onto the piston rod to the top of the threads.
9. Continue to push the piston rod back into the cylinder until it engages the crosshead.
Gently guide the piston rod into the crosshead and screw the piston rod into the
crosshead using a strap wrench or the piston rotation tool as shown in Figure 4-11.
10. Follow the instructions on the proper procedure for setting the cylinder end clearance in
Paragraph 4-13. Then tighten the crosshead lock nut, again following the proper
procedure as outlined in Paragraph 4-13.
11. If required, install the crosshead counterweight and tighten the capscrews to the proper
torque specified in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph
5-3.8 in this Instruction Manual. Wire tie the bolts together on each side remembering to
position the wire so that it pulls on the bolt head in the tightening direction.
12. As a check of a proper crosshead installation, it is suggested that the unit be barred
through one complete revolution while watching the crosshead to see if it runs true in
the crosshead guide. As a final check, the piston rod runout procedure (Paragraph 4-
10.2) should be followed to verify the piston rod runout.
13. Check to make sure that no tools have been left inside the frame and replace the frame
4-27
top cover, frame extension covers and distance piece (yoke) covers. Also replace the
outer head of the cylinder.
4-10. CROSSHEAD SHOES
The crosshead shoes are fitted at the factory with the clearance listed in CHAPTER 5,
GENERAL DATA AND SPECIFICATIONS Paragraph 5-2 of this Instruction Manual, between
the top shoe and upper crosshead guide. However, this clearance as well as the compressor
piston rod alignment must be checked before starting up a new unit and also after any
replacement of the compressor cylinder, piston, piston rod, crosshead or crosshead shoes.
Adjustment or replacement of the crosshead shoes is indicated when the shoes become noisy
or when the compressor piston rod runout exceeds the specified limits.
4-10.1. Crosshead Shoe Replacement
SERVICE NOTE
It is not necessary to completely remove the crosshead from the

frame extension to replace the crosshead shoes.
safety precautions as described previously in Paragraph 4-2.

cylinder.
The following procedure is recommended for replacing the crosshead shoes:
1. Remove the outer head of the cylinder that corresponds to the crosshead being serviced
only if the piston rod rotation tool (see Figure 4-11) will be used.
2. Remove the frame top cover, frame extension covers and distance piece (yoke) covers
that will give access to the crosshead being serviced.
4-28

3. Bar the compressor over until the cylinder is at top-dead-center. Refer to Figure 4-10.
Remove the lockwire (#8) and capscrews (#5) that fasten the two pin end caps (#4) to
the crosshead (#1) then remove the crosshead pin caps.
connecting rod is pulled out of the crosshead. Attach suitable lifting tackle to facilitate
5. Inspect the condition of the pin for excessive wear or damage; repair or replace if
compressor over carefully withdrawing the connecting rod from the crosshead. Stop
barring when the connecting rod has cleared the crosshead sufficiently to allow the
crosshead to be turned 90°. Be careful not to damage the crosshead guide.
7. Remove all the setscrews (#10) that lock the capscrews (#7) in place. Immediately
mark the crosshead to identify which crosshead shoe (#6) is positioned on top.
4-29
8. Place a suitable protected support inside the distance piece (yoke) as close to the
crosshead as possible to raise and support the piston rod when the crosshead is turned
and the shoes no longer support the crosshead.
9. Rotate the piston rod 90° using a mechanical strap (parmalee) wrench or the piston
rotation tool as shown in Figure 4-11.
SERVICE NOTE
Ensure that the shims (#9) which are removed are reinstalled in the
same position. This minimizes the change to both the crosshead
shoe clearance and the piston rod runout.
10. Remove a crosshead shoe (#6) one at a time. Remove the capscrews (#7) that hold the
shoe onto the crosshead (#1). Gently remove the crosshead shoe, and then remove the
shims (#9).
There is a hole in the crosshead shoe shim that must align with
the drilled holes in both the crosshead and crosshead shoe to
ensure sufficient lubrication of the crosshead shoe. If the hole
is not aligned properly, the crosshead shoe will be quickly
destroyed.
11. Install the new crosshead shoe (#6) making sure that the shims (#9) are reinstalled in
the same position. Apply a light coat of Loctite® 242 Threadlocker to the threads of the
capscrews (#7) and tighten the capscrews to the proper torque specification as shown
in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-3.8 in this
Instruction Manual.
12. If required, repeat Steps 10 through 11 for the other crosshead shoe.
13. Rotate the piston rod back 90° using a strap wrench or the piston rotation tool as shown
in Figure 4-11 making sure that the proper crosshead shoe is positioned on top. Then
remove the piston rod support.
4-30
14. Check that the crosshead shoe is sitting down on the guide by ensuring that a 0.0015
inch (0.04 mm) feeler will not fit between the crosshead shoe and guide on either bottom
end. Also check the top shoe-to-crosshead guide running clearance against the value
specified in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-2 in
this Instruction Manual. If required, adjust the top shoe-to-crosshead guide clearance
by adding or removing shims to the top crosshead shoe only.
15. Install all the locking setscrews (#10) that lock the capscrews (#7) on both crosshead
shoes and tighten securely.
16. Slowly rotate the crankshaft to top-dead-center position using blocking to support the
small end of the connecting rod and help guide it into the crosshead.
17. Attach suitable lifting tackle to lift the crosshead pin (#2), then lubricate and install the
pin (#2). Install the two crosshead pin caps (#4) and tighten the capscrews (#5) to the
torque value specified in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS
Paragraph 5-3.8 in this Instruction Manual. Wire tie (#8) together the bolts (#5) on each
side remembering to position the wire so that it pulls on the bolt head in the tightening
direction.
18. As a check of a proper crosshead installation, it is suggested that the unit be barred
through one complete revolution while watching the crosshead to see if it runs true in
the crosshead guide. As a final check, the piston rod runout procedure (Paragraph 4-
10.2) should be followed to verify the piston rod runout.
19. Check to make sure that no tools have been left inside the frame and replace the
distance piece (yoke) covers, frame extension covers, along with the frame top cover. If
required, also replace the outer head of the cylinder.
4-10.2. Piston Rod Runout Adjustment
With the compressor cylinder correctly installed and the piston rod crosshead lock nut
properly tightened (see Paragraph 4-13), check the crosshead to be sure it is resting squarely
on the lower guide. Do this by checking for clearance under the bottom crosshead shoe; a
0.0015 inch (0.04 mm) feeler should not enter between the center of the bottom shoe and guide
at either end of the shoe. Measure the clearance between the top shoe and the upper guide at
all four corners. Record these clearances for later reference.
One of the primary reasons to keep rod runout within limits is to keep the rod running
true through the packing, thus ensuring the longest possible packing life with the least amount
of leakage.
Piston rod runout is usually checked with the unit "cold". Vertical rod runout under these
conditions is mainly influenced by the crosshead-to-crosshead guide cold clearance and the
compressor piston-to-cylinder bore clearance. Because the compressor piston "grows" as it
heats up during operation, it is normal to see a cold vertical runout much larger than what it will
be when the unit is operating.
Runout limits are given in Table 4-1. All runout figures assume that the piston end of the
rod is "low" to compensate for thermal growth of the piston. After running for four hours under
full load and temperature conditions, check the "hot" runout. Runout should be as close to zero
as possible.
4-31
There is no adjustment for horizontal piston rod runout, and it should not exceed 0.0030
inch (0.08 mm) if everything is fitted properly.
Table 4-1. Normal Cold Vertical Piston Rod Runout
Cylinder Bore Approximate Cold Runout

Diameter (Inches) (Inches)
4.75 – 7.75 0.0000 – 0.0020

8.00 – 10.50 0.0005 – 0.0025
11.50 – 13.00 0.0015 – 0.0030
14.00 – 16.25 0.0025 – 0.0035
17.50 – 19.00 0.0030 – 0.0055
20.50 – 23.00 0.0040 – 0.0060
24.50 – 26.50 0.0045 – 0.0065
NOTE: All rod runouts will be negative when starting from the outer end. Runouts will
be positive if starting from the frame end.
Factors that can influence piston rod runout are as follows:
1. Lack of proper supports, particularly on larger cylinders where excessive cylinder

"droop" can occur.
2. Excessive piping strain on the cylinder, and/or distorted cylinder supports pulling the
cylinder out of alignment.
3. Cylinder-to-frame joint burrs or debris in the joint, causing the cylinder to be misaligned.
4. Excessive piston or cylinder bore wear. This can be checked by measuring the piston
and bore with the appropriate micrometers.
5. Worn crosshead shoes. Crosshead shoes are the adjustable type and may be shimmed
if worn.
6. A worn (or bent) piston rod. Check rod diameters along the full length of the rod if this is
suspected. Also, check for bending. A worn or bent rod should be replaced.
7. A crosshead lock nut not seating squarely against the crosshead nose. Improperly
machined parts or debris can cause this situation.
The following procedure is recommended for checking and adjusting the compressor
piston rod runout:

4-32
1. Remove the distance piece (yoke) side covers. Bar the compressor over to the top-
dead-center position.
2. Mount a dial indicator in the distance piece (yoke) so that it will read on the top of the
piston rod close to the crosshead. Be sure the indicator is securely mounted and
depress the indicator button, rotating the pointer approximately one revolution on the
dial to preload the dial indicator. Then set the dial to the zero mark.
3. Bar the compressor through 180, starting from the maximum outboard stroke. The
largest reading seen during this 180 traverse to the inboard stroke position, whether
plus or minus, is the total vertical runout and it should be recorded using the proper sign
(±) for the number. In order to check the accuracy of the reading, continue to bar the
compressor an additional 180 (in the same direction of rotation) back to the maximum
outboard stroke position. The dial indicator should now be pointing to zero; if not, the
indicator has moved.
SERVICE NOTE
If the indicator needle "jumps" at the extreme ends of the stroke, it

is an indication of either a loose crosshead lock nut or a nut face
that is not square to the crosshead nose.
4. The piston rod runout is adjusted in the vertical direction by adding or removing shims
between the crosshead and it’s bottom shoe. If the piston rod is high at the piston end,
shims must be added under the bottom shoe. If the piston rod is high at the crosshead
end, shims must be removed from under the bottom shoe. If there is some confusion as
to which end of the piston rod is high, a machinist's level can be placed on the piston
rod to tell whether the crosshead must be raised or lowered. Always remember that the
shim thickness removed or added to one of the shoes must then be either added or
removed from the other shoe if the required top shoe-to-crosshead guide clearance is to
be maintained. If the top shoe-to-crosshead guide clearance needs to be adjusted, then
either add or remove shims between the crosshead and top shoe only until the proper
top shoe-to-crosshead guide clearance is achieved.
5. Since the piston rod runout is initially checked and adjusted with the parts cold, the
piston rod should normally be set slightly lower at the piston end to compensate for the
piston thermal expansion when running at the design load and temperature conditions.
The amount the piston is set lower than the crosshead is determined by both the size
and material of the piston. (Larger piston sizes should be set slightly lower to
compensate for the increased expansion.) See Table 4-1.
4-33
6. It is necessary to remove the shim from under the crosshead shoe to adjust the shim
thickness. To remove the shoe, follow the crosshead shoe replacement procedure
found in Paragraph 4-10.1. Take off the shim and add or remove laminations as
required. Generally, adding or removing one shim lamination will change the indicated
rod runout about 0.001 inch (0.03 mm); therefore, to raise the indicated rod runout 0.002
inch (0.05 mm) at the crosshead end, it would be necessary to add two laminations to
the shim used under the bottom shoe. Always remove or add the like number of
laminations to the upper shoe to maintain the required top shoe-to-crosshead guide
clearance.
7. Re-check the piston rod runout with a dial indicator, as described in Steps 2 through 3,
after each shoe adjustment. Always check the rod runout with the piston rod crosshead
lock nut firmly tightened as a loose nut can alter the runout reading.
8. After setting the rod runout initially, and before operating the compressor, check that
there is running clearance between the piston rod and piston rod packing glands/cups.
9. There is no adjustment for horizontal piston rod runout. It is important, however, that the
rod runout be checked in the horizontal direction by rearranging the dial indicator to read
on the side of the piston rod. If the horizontal indicated rod runout exceeds 0.003 inch
(0.08 mm), the cause must be located and corrected. Check the cylinder, yoke and
frame mating surfaces for dirt, nicks or burrs. Another possible cause of misalignment is
an improperly tightened crosshead lock nut or a nut that is not seating squarely against
the crosshead. The possibility of cylinder supports or piping pulling the cylinder out of
alignment should also be explored.
10. Both the piston rod alignment and the crosshead top shoe-to-crosshead guide
clearance should be checked after operating the compressor for at least four hours
under full load and temperature conditions. These checks must be made immediately
after shutting down before the parts have had a chance to cool. Piston rod runout
should be as close to zero as possible and must not exceed 0.002 inch (0.05 mm) in
any plane. The minimum acceptable clearance between the top crosshead shoe and
crosshead guide with the parts at operating temperature is given in CHAPTER 5,
GENERAL DATA AND SPECIFICATIONS Paragraph 5-2 in this Instruction Manual. If it
is necessary to remove the shims to obtain this minimum clearance, be sure they are
removed only from under the top shoe. Record the hot clearance for future reference.
4-11. COMRESSOR CYLINDERS
The standard HOSS cylinder is a water-cooled design cast in nodular iron as shown in
Figure 4-12. Specialized cylinders are also available by request from the Dresser-Rand Gas
Field Compressors Customer Service Group in Tulsa, Oklahoma.
A wide variety of cylinder bore sizes are available from 4.75 inches to 26.50 inches in
diameter. The standard cylinder line-up for the HOSS is shown in Table 4-3.

4-34
TP-5119
Figure 4-12. Typical HOSS Cylinders

4-35
The cylinder bores, valves, valve passages, piston rod packings and any regulation
equipment supplied should be inspected at regular intervals (refer to the routine maintenance
schedule in CHAPTER 3, OPERATION AND TROUBLESHOOTING), and any accumulations of
foreign matter should be removed. Valves must be dismantled, soaked in safety solvent and
physically brushed to soften and remove any deposits; a light scraping usually will suffice to
clean the cylinder passages.
Dresser-Rand Type PF valves are used as standard in HOSS cylinders. Detailed

instructions for the servicing of these valves can be found in this chapter in Paragraph 4-19.
With water-cooled cylinders, mud will be deposited in the cylinder jackets, water heads
and packing cooling sleeves if the circulating coolant (usually a mixture of 50-50 ethylene glycol
and water) is dirty. This will eventually obstruct the flow of coolant unless care is used to
prevent such an accumulation. Clogged passages will interfere with proper cooling, which will
result in possible damage to the cylinder, pistons and packing.
The cylinder water jacket cover plate or hand hole covers (depending on design) should
be removed occasionally and the water jackets and passages inspected. If any mud deposits
are found, clean them out thoroughly and flush the jackets with clean water.
The piston and ring clearances for the standard water-cooled HOSS cylinders are given
in Table 4-3. Clearances for non-standard bore diameter cylinders will be given in a separate
addendum sheet prepared for your unit. The specified clearance limits are those to which the
parts are originally assembled. Varying operating conditions at different installations make it
generally impractical to specify the maximum acceptable clearances. Careful observation by the
operator and good judgment by the mechanic are often the most effective means of determining
when the clearances have become excessive and an adjustment or replacement of parts is
required.
4-11.1. Removing the Compressor Cylinder
safety precautions described previously in Paragraph 4-2.

cylinder.
The compressor cylinder can be opened and the various cylinder components serviced
as described in the maintenance instructions that follow.
4-36
Remove the compressor cylinder from the compressor frame as follows:
1. If the complete cylinder is to be removed from the compressor frame, it is first necessary
to disconnect all of the gas, oil, water and control piping from the cylinder, as applicable.
2. The compressor piston and piston rod should be removed next from the cylinder as
explained in the instructions that follow in Paragraph 4-12.1.
3. To remove the cylinder from the frame, support the weight of the cylinder and distance
piece (yoke) with the proper rigging from an overhead hoist of sufficient capacity or
other means. Refer to Table 4-3 for the weight of the cylinder and distance piece (yoke)
assembly. Then unbolt the distance piece (yoke) from the frame, along with any
cylinder supports, and carefully lower the cylinder assembly to the floor. Refer to Figure
4-12.
4. If required, remove the distance piece (yoke) and tie rods from the cylinder.
4-11.2. Installing the Compressor Cylinder
Normally, the cylinders are mounted on the compressor frame when it is shipped to the
installation site. However, in some instances, usually because of shipping and packaging
restrictions, the cylinders are shipped separately and must be installed at the compressor site.
Refer to the installation plans prepared for the compressor to determine the position in which
each cylinder is to be mounted.
SERVICE NOTE
Cylinders must be returned to their original mounted locations on

the frame. Never change the cylinder mounting locations.
Install one cylinder at a time on the unit. Where cylinder supports are used, insert the
leveling screws in the support bases being sure that the threads are greased and free to turn.
Install and align the compressor cylinder on the compressor frame as follows:
SERVICE NOTE
All mating surfaces must be checked for flatness. Flatness of each

mating component should be within 0.002 inch (0.05 mm).
1. Referring to Figure 4-12, if disassembled, thoroughly clean the mating surfaces between
the cylinder and the distance piece (yoke). Coat both surfaces with gasket shellac - do
not use a gasket.
2. A locating shoulder, which fits closely into the yoke bore, centers the cylinder in the
distance piece (yoke). Insert the (4) four cylinder-to-frame tie rods through the yoke
and thread them into the cylinder until they are snug. Then using (4) four 0.750-10UNC
x 2.00-inch long capscrews, bolt the cylinder and distance piece (yoke) together.
3. Thoroughly clean the mating surfaces between the frame extension and distance piece
4-37
(yoke). Coat both surfaces with gasket shellac - do not use a gasket.
4. Using a suitable lifting sling and an overhead hoist of sufficient capacity, mount the
cylinder and distance piece (yoke) assembly to the frame. Refer to Table 4-3 for the
weight of the cylinder and distance piece (yoke) assembly. The cylinder yoke is
centered in the frame extension by a locating shoulder, which fits closely into the frame
extension bore. Support the cylinder and snug down only the top (2) two cylinder-to-
frame tie rod nuts.
5. Clean the gasket surface for the inlet (flange) on top of the cylinder and place a
machinist’s level on this surface parallel to the crankshaft. Rotate the cylinder until the
gasket surface is level, then secure the cylinder by tightening all (4) four of the cylinder-
to-frame tie rod nuts following the procedure specified in CHAPTER 5, GENERAL DATA
AND SPECIFICATIONS, Paragraph 5-3 in this Instruction Manual.
6. Depending on the particular compressor, the cylinder may be equipped with a distance
piece (yoke) support, or an outer end cylinder support, or a combination of both. With
either support location, the support(s) must be adjusted so that it is supporting the
weight of the cylinder but not placing an upward/downward strain on the cylinder-to-
frame bolting. The following procedure is recommended when an outer end cylinder
support is used:
A. Loosen the bottom (2) two cylinder-to-frame tie rod nuts and all (4) four
capscrews, leaving the top (2) two cylinder-to-frame tie rod nuts snugged down
tightly.
B. Carefully raise the cylinder with the support leveling screws until a 0.0015 inch
(0.04 mm) feeler gauge can just be started at the bottom cylinder-to-frame joint.
C. Lower the cylinder to just close the joint, then retighten the bottom (2) two
cylinder-to-frame tie rod nuts to the value specified in CHAPTER 5, GENERAL
DATA AND SPECIFICATIONS, Paragraph 5-3.8 in this Instruction Manual.
7. If not already removed, remove the outer head from the cylinder. Using a machinist’s
level having a cross level, check that the cylinder bore in the piston travel area is level.
Locate the cause of any misalignment. Do not use the support leveling screws to
force the cylinder into alignment.
8. Check the level of the crosshead guide. The cylinder bore and the crosshead guide
need not be perfectly level, but both should be in the same plane. Do not use the
cylinder inlet (or discharge) connection as an alternate to the cylinder bore. If the
crosshead guides are level but one or more cylinders is not, the most likely cause is dirt
or raised material in the joint where the cylinder fits the distance piece (yoke) or where
the yoke mates with the frame extension.
The continuing assembly of the compressor cylinder includes the assembly and
installation of the piston and piston rod, piston rings, piston rod packing and valves. Also
included is the adjustment of the piston end clearances. Follow the appropriate assembly
procedures outlined in this Instruction Manual to complete these tasks.
4-38
4-12. PISTON AND PISTON RODS
Before doing any maintenance work on the piston and piston rods, closely observe the
minimum safety precautions as described previously in Paragraph 4-2.

cylinder.
4-12.1. Removing the Piston Rod
1. Remove the cylinder outer head, frame top cover, frame extension covers and distance
piece (yoke) covers that will give access to the piston rod being removed.

SERVICE NOTE
If a balance weight or weights are present, depending on the size of

the weights, it may be necessary to remove them first. Slide the
weight(s) out toward the stuffer plate to get access to the lock nut.
In very rare instances the stuffer plate may have to be removed to
make additional room.
4-39
2. If required, bar the compressor over until there is easy access to the crosshead balance
weight. Make sure to identify the location of the counterweight on the crosshead to
allow replacement back in the same location. Remove the lockwire and capscrews.
Sling the counterweight from an overhead hoist of sufficient capacity and/or block the
counterweight inside the frame extension to support the counterweight.
3. Bar the compressor over until the cylinder is at bottom-dead-center. Block the
crosshead by jamming wooden blocks between the crosshead and the frame extension
to prevent twisting of the crosshead and/or connecting rod when removing the
crosshead lock nut. Loosen the crosshead lock nut on the piston rod.
SERVICE NOTE
When the packing cup and oil scraper gland assemblies are
removed from the cylinder, be sure that the parts are marked or
tagged to facilitate the proper reassembly.
4. Remove the piston rod pressure packing and the piston rod oil scraper rings as
explained later in these instructions in Paragraphs 4-16 and 4-17, respectively. Always
remove the packing rings before pulling or installing the piston rod; never slide these
rings over the end of the rod.
5. Unscrew the piston rod from the crosshead using a strap wrench or the piston rotation
tool as shown in Figure 4-11, until the piston rod thread disengages from the crosshead.
6. Pull the piston and piston rod assembly through the outer end of the cylinder. Be careful
to support the piston until the piston rod is clear of the cylinder to prevent bending or
scratching the rod. Mark the piston and rod assembly so that it can be installed back
into the same cylinder.
7. Set the piston and rod in a safe place and protect the finished surfaces from damage. If
the piston and rod are not integral, and if the piston is to be separated from the piston
rod, then refer to the proper piston and rod disassembly and reassembly instructions
that follow.
4-40
4-12.2. Piston and Rod Disassembly – Cast/Nodular Iron Pistons
The SUPERBOLT® torque nut is threaded onto the piston rod with a washer positioned
between the crosshead or piston and the torque nut as shown in Figure 4-13. Once the torque
nut is properly positioned, actual tensioning is accomplished by tightening the jackbolts (located
around the main thread) against the washer.
1. Install the piston rod assembly in a clamping fixture as shown in Figure 4-14, or a similar
device that will keep the piston rod from turning while loosening the piston rod nut. Use
a soft bearing material (such as brass or copper) next to the rod surface to prevent the
scoring or scratching of the piston rod.
2. Using the appropriate CIRCULAR PATTERN shown in figure 4-15, loosen each
individual jackbolt and then run it back in until it just touches the hardened washer.
Repeat this process until the torque nut comes loose.
3. After all of the jackbolts have been loosened, then the torque nut body and washer can
be removed from the piston rod.
4. Finally, using an overhead hoist and sling of sufficient capacity, carefully remove the
piston from the piston rod.`
Figure 4-13. Piston SUPERBOLT® Torque Nut Application

4-41
TP-5120
Figure 4-14. Suggested Piston Rod Clamping Fixture

4-42
Figure 4-15. Torque Nut Loosening/Tightening Sequence
4-12.3. Piston and Rod Assembly – Cast/Nodular Iron Pistons
The SUPERBOLT® torque nut is threaded onto the piston rod with a washer positioned
between the crosshead or piston and the torque nut as shown in Figure 4-13. Once the torque
1. Install the piston rod in a clamping fixture as shown in Figure 4-14, or a similar device
that will keep the piston rod from turning while tightening the piston rod nut. Use a soft
bearing material (such as brass or copper) next to the rod surface to prevent the scoring
or scratching of the piston rod.
2. Inspect the mating surfaces of the piston rod collar, piston faces, flat washer and torque
nut for dirt, burs and general condition. Clean up the parts as required.
3. Using an overhead hoist and sling of sufficient capacity, assemble the piston onto the
piston rod as shown in Figure 4-13. Check the seating surfaces between the piston rod
collar and piston by “bluing” to assure that at least 85 percent of evenly distributed
seating contact is made on both contact surfaces. If necessary, lap the contact surfaces
with valve lapping compound. Be sure to remove all traces of the lapping compound
using soap and hot water.

4-43
DANGER
Never use a petroleum-based lubricant with oxygen equipment.
A mixture of oxygen with petroleum-based lubricants is
violently explosive and could cause property damage, personal
injury or death.
If the jackbolts must be cleaned or re-lubricated, they MUST be

lubricated with the type of lubricant stamped on the O.D. of the
torque nut body. The current version of the torque nuts are
lubricated with Dow Corning® “G-n” Metal Assembly Paste, per
the stamped “G-n” on the O.D. of the nut. Dow Corning® “G-n”
Metal Assembly Paste is available through most commercial
suppliers. Previous versions of the torque nuts were
lubricated with SUPERBOLT® “JL-M” molybdenum disulfide-
based lubricant, and are stamped “JL-M” on the torque nut
O.D. SUPERBOLT® “JL-M” lubricant is only available through
SUPERBOLT®. The jackbolt torque value is based exclusively
on the type of lubricant used. Consult with Dresser-Rand
Reciprocating Technical Support at 1-607-937-2626 if you
should desire to change the type of jackbolt lubricant.
4. Prior to assembly of the piston onto the piston rod, thoroughly degrease with solvent
and dry the piston rod threads, the rod thread inside of the torque nut body and the flat
washer supplied with the torque nut. Lightly coat just the piston rod threads with a small
amount of Dow Corning® “G-n” Metal Assembly Paste.
5. Apply a small amount of the specified jackbolt thread lubricant to the thrust end of each
jackbolt. Ensure that the thrust end of each jackbolt is retracted below the face of the
torque nut body.
6. Install the flat washer and then the torque nut body onto the piston rod. Tighten the
torque nut body as tight as possible by hand. (Make sure that the flat washer is
bottomed out in the counterbore of the piston before tightening the jackbolts.)
7. Tighten the jackbolts to 10 percent of the final torque value stamped on the torque nut
body O.D. following the appropriate STAR PATTERN shown in Figure 4-15, unless
otherwise indicated by the directions supplied with the torque nut.
8. Tighten the jackbolts to 25 percent of the final torque value following the appropriate
STAR PATTERN shown in Figure 4-15.
STAR PATTERN shown in Figure 4-15.
CIRCULAR PATTERN shown in Figure 4-15.
4-44
11. Tighten the jackbolts to 100 percent of the final torque value, again following the
appropriate CIRCULAR PATTERN shown in Figure 4-15.
12. Repeat Step 11 three or four times or until the jackbolts do not advance anymore upon
further torquing.
13. Remove the piston and piston rod assembly from the clamping fixture used.
4-12.4. Piston and Rod Disassembly – Aluminum Pistons
1. Install the piston rod assembly in a clamping fixture as shown in Figure 4-14, or a similar
device that will keep the piston rod from turning while loosening the piston rod nut. Use
a soft bearing material (such as brass or copper) next to the rod surface to prevent the
scoring or scratching of the piston rod.
2. Remove the piston nut-locking setscrew. Then remove the piston rod nut using the
wrench adapter provided. If available, a suitable size impact wrench is ideal for
loosening the nut. If it is necessary to sledge or use a cheater on the wrench, then first
support the end of the piston to prevent the bending of the piston rod.
3. Carefully remove the outer end piston collar. Utilizing an overhead hoist and sling of
sufficient capacity, remove the piston. Finally, remove the frame end piston collar from
the piston rod.
4-12.5. Piston and Rod Assembly – Aluminum Pistons
1. Install the piston rod in a clamping fixture as shown in Figure 4-14, or a similar device
that will keep the piston rod from turning while tightening the piston rod nut. Use a soft
bearing material (such as brass or copper) next to the rod surface to prevent the scoring
or scratching of the piston rod.
2. Inspect the mating surfaces of the piston rod collar, frame end and outer end piston
collars, piston faces and piston rod nut for dirt, burrs and general condition. Clean up
the parts as required.
3. Place the frame end piston collar on the rod and check the mating surfaces between the
rod shoulder and collar by "bluing" to assure that at least 85 percent of evenly
distributed seating contact is made on both surfaces. Using an overhead hoist and sling
of sufficient capacity, assemble the piston onto the piston rod and again check the
mating surfaces by “bluing”. Repeat this process for the outer end piston collar contact
to the piston. If necessary, lap the contact surfaces with valve lapping compound. Be
sure to remove all traces of the lapping compound using soap and hot water.
SERVICE NOTE
With step cylinders, both an inboard and outboard piston and piston
spacer, as well as the piston collars and nut must be “blued” to 85
percent contact in the appropriate order.
4-45
4. Finally check the mating surfaces between the piston nut and the outer end piston collar
for adequate contact as in Step 3. If the bearing area is insufficient, then check the
squareness of the nut face with the nut threads. Scrape or lap the faces, if necessary,
using a valve lapping compound until the adequate bearing area is obtained. Again, be
sure to remove all traces of the lapping compound using soap and hot water.

DANGER
Never use a petroleum-based lubricant with oxygen equipment.
A mixture of oxygen with petroleum-based lubricants is
violently explosive and could cause property damage, personal
injury or death.
5. Prior to assembly of the piston onto the piston rod, thoroughly degrease with solvent
and dry the piston rod threads, piston collars and piston nut. Coat the piston rod and
piston nut threads with a suitable anti-galling compound, such as Felpro C-100
(distributed by Felpro, Inc., Skokie, IL 60776) or Jet Lube #20 (distributed by Marlon
Supply Co., 5016 Edgewood Rd., Crystal Lake, IL 60014). Also apply a thin film on the
seating faces of the piston nut and outer end piston collar. Tighten the piston nut to 150
ft.-lb. (200 Nm) to ensure adequate metal-to-metal contact.
6. Refer to Graph 4-1 to determine the number of degrees the piston nut must be turned
with relation to the piston rod. The use of torque is strongly discouraged because of
the variations obtained with small changes in lubrication and surface condition of
the mating parts.
7. Scribe a line (A) through the centerline of the rod and extend it out onto the piston as
shown in Figure 4-16.
8. Measure from the scribe line (A) the number of degrees that the piston nut must be
turned. Prick punch point (B) on the piston and then scribe a line through this point (B)
and the centerline of the piston rod.
SERVICE NOTE
With the wrench socket on the adapter, it will be impossible to see

the scribe mark on the piston nut. It is essential that the scribe
mark between the piston rod and piston nut line up. It is therefore
recommended that the scribe mark on the socket be turned slightly
beyond the second scribe mark on the piston, as the piston may
have rotated slightly on the rod due to friction.
4-46
TP-5121
Graph 4-1. Piston Nut Tightening Angle
9. Install the piston nut adapter. Mark the adapter (or socket, if an impact wrench is being
used) adjacent to the first scribe line (A) as shown in Figure 4-16.
10. Tighten the piston nut until the mark on the adapter (or socket) coincides with the
second scribe line (B).
4-47
Figure 4-16. Marking Piston Nut and Adapter or Socket
SERVICE NOTE
It is anticipated that the piston will go beyond the original scribe

mark; therefore, it is imperative to re-scribe each time the piston nut
is tightened.
11. If a new piston, piston rod or piston nut is being installed, tighten the assembly at least
twice to the full pre-load as described in Steps 7 through 10. Then, loosen the
assembly again and repeat Steps 7 through 10 (for at least the third time) to secure the
piston onto the piston rod.
12. After completing the piston nut tightening procedure, drill and tap the piston rod and nut
for the locking setscrew. (Facing the outer end of the piston, half of the tapped hole
should be in the piston rod and half in the piston nut.)
13. Lock the piston nut to the piston rod using the setscrew.
4-48
4-13. INSTALLING the PISTON ROD and ADJUSTING END CLEARANCE
When adjusting the piston end clearance, it is desirable to have more clearance at the
outer end than at the frame end. This is because expansion from operating heat tends to
increase the frame end clearance and decrease the outer end clearance. For this reason, when
setting the piston end clearance, the outer end is usually given about 50% more lineal clearance
than the frame end. Specific end clearances are shown on the cylinder nameplate. Standard
HOSS cylinder clearances are as follows:
Frame End = 0.043-0.082 inch (1.09-2.08 mm)

Outer End = 0.064-0.123 inch (1.63-3.12 mm)

The operator must insure that the driver will not start either by
engine-driven units or by insuring that power cannot be turned
The piston end clearance, after having been correctly set at the time of installation,
should rarely require adjustment. It should be checked occasionally as follows:
To measure the end clearance, first remove the cylinder indicator plugs for each end.
When the machine is cold, find the exact clearance by barring over the compressor until the
piston is at the innermost end of its stroke. Using feeler gauges, measure the distance between
the face of the piston and the inboard cylinder head. Note this measurement and then bar the
compressor 180 to bring the piston to the outermost end of its stroke. Again using feeler
gauges, measure the clearance between the face of the piston and the outboard cylinder head.
Note any difference in the clearances and then screw the piston rod in or out of the crosshead
to make the clearance about 50% more at the outer end than at the frame end.
If it is necessary to change the clearance at either end, loosen the lock nut on the piston
rod at the crosshead following the required Steps in Paragraph 4-12.1 of this Instruction
Manual. Turn the piston rod in or out of the crosshead as required. Each quarter turn of the rod
changes the end clearance by 0.031 inch (0.79 mm). After the proper clearance in the cylinder
is established, tighten the crosshead lock nut on the piston rod, as described in Step 5 of this
section.
4-49
1. Place an entering sleeve onto the end of the piston rod to protect the packing. Coat the
piston rod and sleeve with oil, then push the piston assembly into the cylinder. Remove
the entering sleeve.
SERVICE NOTE
If a balance weight or weights are present, depending on the size of

the weights, it may be necessary to assemble the weight(s) onto the
crosshead after the lock nut has been tightened.
2. Install the lock nut on the piston rod and balance weights (if required) making sure the
machined surface will contact the crosshead.
Never use a pipe wrench on the piston rod. Take every

precaution to avoid scratching or nicking the piston rod
surface. Even a slight nick in the rod can ruin the packing
rings.
3. Screw the piston rod into the crosshead until the required piston frame end clearance is
obtained. (Refer to the instructions above for a discussion of the piston end clearance.)
A mechanical strap (parmalee) wrench or a piston rotation tool (see Figure 4-11) should
be used to screw the piston rod into the crosshead. Snug the piston rod lock nut
against the crosshead, but do not tighten it at this time. Check to see that there is some
clearance between the piston rod and the connecting rod in the crosshead.
4. Check the seating surfaces between the crosshead and lock nut by "bluing" to ensure
that at least 80% seating contact is made. Check that the seating area is uniform
completely around the circumference and across the seating face. If the seating is
insufficient, check the squareness of the nut face with the nut threads. Scrape or lap
the faces, if necessary, using a valve lapping compound until adequate seating area is
obtained. Remove all traces of the compound using soap and water.
5. Tighten the crosshead lock nut as follows:
A. Block the crosshead by jamming wooden blocks between the crosshead and the
frame extension to prevent twisting the crosshead and/or connecting rod during
tightening.
B. Coat the piston rod and lock nut threads with a suitable anti-galling compound or
extreme pressure lubricant, such as Felpro C-100 (distributed by Felpro, Inc.,
Skokie, IL 60776) or Jet Lube #20 (distributed by Marlon Supply Co., 5016
Edgewood Rd., Crystal Lake, IL 60014). Also apply a thin film on the seating
faces of the lock nut and crosshead. Tighten the nut to 150 ft.-lb. (200 Nm) to
ensure adequate metal-to-metal contact.
C. Refer to Figure 4-17. Match mark a flat on the nut with the face of the
crosshead using a punch, scribe, or other suitable instrument. To mark the
proper nut-tightening angle, measure clockwise 15 degrees from the first mark
using a protractor and make a second mark on the crosshead face.
D. Tighten the lock nut until the first mark (on the nut flat) is aligned with the second
4-50
mark (on the crosshead face).
TP-5122
Figure 4-17. Marking Crosshead and Crosshead Lock Nut Tightening Angle
7. Check the piston rod runout and adjust it as required as described in Paragraph 4-10.2
of this Instruction Manual.
8. Install the outer head assembly onto the cylinder and tighten to the value specified in
CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-3 in this
Instruction Manual. Check the piston end clearance at each end of the stroke as
described in the instructions above.
4-14. INSPECTION / MAINTENANCE of CYLINDER BORES
Follow the instructions in Paragraph 4-11.1 of this Instruction Manual for the proper
procedure on how to remove the cylinder if required.

1. Place the cylinder in a clean work area and wipe down the bore with clean rags. It may
be necessary to use a safety solvent to remove some of the deposits.
2. Shine a light down the cylinder bore and visually inspect the surface for scratches,
gouges and and/or nicks.
3. Using the appropriate internal micrometer, measure the bore at the frame end, center
4-51
portion and outer end at the limits of piston travel, taking measurements 90 apart.
Comparing the measurements will give figures for taper (end-to-end in the same bore
position) and out-of-round (the same bore position but 90 apart). Maximum allowable
taper is determined by multiplying the stroke (whether in inches or mm) by 0.0005.
Maximum allowable out-of-round is determined by multiplying the bore size (whether in
inches or mm) by 0.0005. This applies to TFE or thermoplastic rings.
4. A bore not exceeding the limits specified above may be cleaned up just using a glaze
breaker or a rigid portable hone. For the recommended procedure and surface finish
required, see Paragraph 4-14.1 "Honing", later in this section. After honing, new piston
rings can then be installed.
5. Any wear in excess of the limits specified above indicates that cylinder bore
reconditioning is required. Any taper and/or out-of-round condition must be corrected by
minimal re-machining the cylinder bore, then honing to a maximum of 0.062 inch (1.57
mm) oversize, or out to the cylinder counterbore diameter, which ever is less.
NOTE
Generally, standard rings may be used in cylinders worn up to the

limits shown in Table 4-2. For cylinders with bore diameters greater
than specified, oversize piston rings should be used. The bore
must be round. Oversize rings are not the cure for an out-of-round
or tapered bore condition. When ordering oversize rings, furnish
Dresser-Rand with the cylinder bore measurements. Rings ordered
through Dresser-Rand will be tagged, indicating the proper side and
end gap clearances. Use Table 4-2 as a guide to determine at what
increase of bore diameter are oversize piston rings required.
Table 4-2. Cylinder Reconditioning Data

Original Cylinder Size Maximum Bore Diameter Increase
Nominal Bore Diameter Allowed Before Oversize Rings Required
(Inches) (Inches)
4.75 0.0143
5.75 0.0173
6.00 0.0180
6.50 0.0195
7.00 0.0210
7.75 0.0233
8.00 0.0240
9.00 0.0270
9.50 0.0285
10.50 0.0315
11.50 0.0345
12.25 0.0368
13.00 0.0390
14.00 0.0420
15.00 0.0450
16.25 – 26.50 0.0480
NOTE: Inch-to-millimeter conversion-multiply inches by 25.4 to obtain millimeters.
4-52
4-14.1. Honing
NOTE
The major difference between a glaze breaker and a cylinder hone

is that the glaze breaker will follow the contour of the cylinder. If the
bore is out-of-round, the glaze breaker will only clean it up; it will not
"true up" the bore. The hone, on the other hand, will true up a
slightly out-of-round or tapered cylinder bore, although it too tends
to follow the existing bore contour.
In all cases where a bore is being field reconditioned, it is important to achieve a surface
finish at least as good as the factory finish to ensure adequate ring seating and longevity. Hone
the cylinder bore to restore the surface finish. Bores finishes should be at least Ra 32 µ inches
(0.8 µm). Honing will polish scratches and remove burrs, and will often restore a cylinder bore
after minor scuffing. This can be achieved using a glaze breaker or hone, finishing with extra
fine honing stones. A crosshatch pattern can be used if desired. ALWAYS WASH THE GRIT
FROM HONING OUT OF THE CYLINDER BORE USING SOAP AND HOT WATER.
4-15. NON-METALLIC COMBINATION PISTON & RIDER RINGS
These segmented, non-metallic combination piston/rider rings function as both piston

rings and rider rings. The function of the piston ring is to create a seal between the piston and
cylinder bore. There must be sufficient clearance at the side and underneath so that gas
pressure can force the ring outward against the cylinder bore and against the ring groove. The
function of the rider ring is to carry the weight of the piston and part of the piston rod. These
“combo rings” are used as standard on all HOSS cylinders. The 26.00 and 26.50 inch (660 and
673 mm), “combo rings” also contain a 3/16” round wire expander to ensure sealing pressure
toward the cylinder bore.
The combination piston/rider rings also hold the piston away from the cylinder bore
during operation, thus preventing piston-to-cylinder bore contact and the resultant scoring and
cylinder wear. To promote longer ring life, the surface finish of the cylinder bore must be a
minimum of Ra 32 µ inches (0.8 µm).
Standard size rings may be used in oversized cylinder bores up to 0.003 inch (0.08 mm)
for each inch (25.4 mm) of bore diameter up to and including 0.045 inch (1.14 mm) maximum
oversize. For cylinders with bore diameters greater than that allowed for standard size rings at
the nominal bore size, oversized piston rings should be used. Remember that the bore must be
round. Oversize rings will not correct or compensate for out-of-round or tapered bore
conditions.
4-15.1. Handling Instructions
These piston rings are fragile (when compared to metallic parts) and can be easily
damaged by careless handling. Always use extreme care during storage, handling, installation
and removal of these rings.
4-53
During long shutdowns (over six months), the pistons and rods should be removed from
the compressor. Coat the piston and rod assembly with a rust preventative that meets Military
Specification MIL-C-16173 latest revision. The rings are to be removed from the piston and
stored flat. No special covering or rust preventative is required for the rings. Do not lay the
piston and rod assembly down with the rings installed.
4-15.2. Establishing Ring Wear Rate
The combination piston/rider rings may wear more rapidly than other rings because of
the functions they are designed to perform. (These are sealing of the cylinder bore, and the
prevention of piston to cylinder bore contact.) Operating and maintenance personnel must take
this factor into consideration when scheduling inspections and normal part replacement.
As wear occurs, piston rod runout will eventually exceed allowable limits. If oversized
rings are installed in an oversized bore the ring wear factor is more critical because the rod drop
will be increased by one-half the total oversize. For example, if the bore is 0.026 inch (0.66
mm) oversize, the rod will drop an additional 0.013 inch (0.33 mm) before the bottom clearance
or ring radial thickness indicates replacement is required. Therefore, the operator must keep in
mind that the rings must be replaced when their original radial thickness is reduced by one-half
of the original (new radial) thickness. Also, note the clearance between the piston rod and
packing housing. DO NOT allow these items to come into contact with each other.
Because of the many variables involved, it is impossible to accurately predict the rate of
ring wear. (Some of the variables are pressure, temperature, lubrication, or lack thereof, piston
weight, gas type, gas wetness, gas cleanliness and cylinder bore finish.)
To prevent scoring of the cylinder bore, piston or the piston

rod, the amount of ring wear (clearance between the piston and
cylinder bore) must be checked on a regular basis. This action
will tell the operator if wear is excessive, allowing replacement
before damage is done.
The importance of frequently checking ring wear rate cannot be over-emphasized. The
rate of ring wear must be determined so that a replacement schedule can be established.
Measurement of the piston to cylinder bore clearance ("A", Figure 4-18) should be taken at
intervals of 10, 100, 250, 500 and 1000 hours. Record these numbers for future reference, or
plot a simple wear versus time curve that will indicate both the rate of wear and the approximate
number of hours running time before the combination rings need to be replaced.
NOTE
When plotted, the wear rate curve will usually show a relatively
rapid rate of wear during the first few hours of operation. As the
rings wear, the curve should flatten out.
4-54
TP-5123
Figure 4-18. Locations for Checking Clearance - See Table 4-3 for Dimensions
4-15.3. Replacing Rings
Rings are replaced when the bottom piston to cylinder bore clearance ("B", Figure 4-18)
has been reduced to the minimum allowable clearance or if the original radial thickness of the
rings has been reduced by one-half.
Never measure piston-to-cylinder bore clearance through a

valve opening; always remove the outer head. Refer to the
appropriate instructions to remove and install the outer head.
Failure to comply with this warning may result in severe
personal injury caused by compressor roll.
4-15.4. Installing Rings
The rings must be assembled in the piston grooves as the piston is slid into the cylinder
bore. These rings will extend beyond the piston's outside diameter after installation. After the
piston is installed, measure the bottom clearance between the piston and cylinder bore (see "A"
Figure 4-18). This is the point of reference from which the amount of wear will be determined.
4-55
Table 4-3. Piston and Ring Clearance for Standard HOSS Cylinders
"E" “F” “F”

Nominal Lifting1 Groove "C"
2 Piston3 Side Total Total
Cylinder Weight Piston Width Running
Ring Clear. (In.) Angle Cut Step Cut
Size of Cylinder Mat'l. (In.) Clear. (In.)
Mat'l. Between End Gap End Gap
Plus Yoke +0.001 Top-New
Ring & New New
(Inches) (lbs) -0.000 Rings
Groove Parts (In.) Parts (In.)
4.75 2200 CI PTFE 0.500 0.023/0.010 0.013/0.009 0.067/0.057 0.095/0.081
5.75 2850 CI PTFE 0.500 0.025/0.011 0.013/0.009 0.081/0.069 0.115/0.098
6.00 2700 CI PTFE 0.500 0.026/0.012 0.013/0.009 0.084/0.072 0.120/0.102
6.50 2930 CI PTFE 0.500 0.027/0.013 0.013/0.009 0.091/0.078 0.130/0.111
7.00 2930 CI PTFE 0.625 0.028/0.014 0.015/0.011 0.098/0.084 0.140/0.119
7.75 3110 CI PTFE 0.500 0.029/0.016 0.013/0.009 0.109/0.093 0.155/0.132
8.00 3110 CI PTFE 0.500 0.030/0.016 0.013/0.009 0.112/0.096 0.160/0.136
9.00 3050 CI PTFE 0.625 0.032/0.018 0.015/0.011 0.126/0.108 0.180/0.153
9.50 3050 CI PTFE 0.625 0.033/0.019 0.015/0.011 0.133/0.114 0.190/0.162
10.50 3050 CI PTFE 0.625 0.035/0.021 0.015/0.011 0.147/0.126 0.210/0.179
11.50 3100 CI PTFE 0.625 0.037/0.023 0.015/0.011 0.161/0.138 0.230/0.196
12.25 3500 CI PTFE 0.500 0.039/0.024 0.013/0.009 0.172/0.147 0.245/0.208
13.00 3500 CI PTFE 0.500 0.040/0.026 0.013/0.009 0.182/0.156 0.260/0.221
14.00 3650 CI PTFE 0.625 0.042/0.028 0.015/0.011 0.196/0.168 0.280/0.238
15.00 3650 CI PTFE 0.625 0.044/0.030 0.015/0.011 0.210/0.180 0.300/0.255
16.25 3650 CI PTFE 0.625 0.048/0.033 0.015/0.011 0.228/0.195 0.325/0.276
17.50 5165 AL PTFE 0.625 0.067/0.053 0.015/0.011 0.245/0.210 0.350/0.298
19.00 5725 AL PTFE 0.625 0.072/0.057 0.015/0.011 0.266/0.228 0.380/0.323
20.50 5600 AL PTFE 0.625 0.077/0.062 0.015/0.011 0.287/0.246 0.410/0.349
22.00 6400 AL PTFE 0.625 0.081/0.066 0.015/0.011 0.308/0.264 0.440/0.374
23.00 6200 AL PTFE 0.625 0.084/0.069 0.015/0.011 0.322/0.276 0.460/0.391
24.50 6500 AL PTFE 0.625 0.088/0.073 0.015/0.011 0.343/0.294 0.490/0.417
26.00 6750 AL PTFE 0.625 0.093/0.078 0.015/0.011 0.364/0.312 0.520/0.442
26.50 6750 AL PTFE 0.625 0.094/0.079 0.015/0.011 0.371/0.318 0.530/0.451
NOTES:
1
= Weight of cylinder plus yoke – does not include piston, piston rod, valves and covers
2
= CI – Cast Iron, AL - Aluminum
3
= PTFE - Carbon-Glass-Carbon Filled Teflon
 Multiply clearance dimension by 25.4 to obtain (soft converted) metric dimension.

 Metric groove width tolerance is +0.025/-0.000 mm.
(A 0.500" width is 12.70 mm; a 0.625" width is 15.88 mm).
 Dimensions Refer to Figure 4-18. All dimensions are for new parts.
4-56
To install the rings, follow these Steps. Clearances are listed in Table 4-3.
1. Check the ring part number against the parts list to ensure the correct parts are being
installed.
2. Manufacture a ring gauge that has the same nominal inside diameter as the cylinder
bore. Insert each ring, measure and record the total ring end gap clearance. See
Figures 4-19 and 4-20 for Angle Cut or Step Cut rings, respectively.
3. Measure the radial thickness of each ring. Record this dimension for future reference.
4. Be sure the piston ring grooves are clean and smooth.
5. Install the packing entering sleeve on the piston rod.
6. Push the piston into the cylinder until the innermost groove is just outside the cylinder.
7. Make if required from thin shim stock, a tool to hold the ring segments in the piston
grooves.
8. Place the ring segments into the piston grooves and take the side clearance as shown
in "E" Figure 4-18. Record these clearances.
9. LIFT the piston slightly and push it into the cylinder until the cylinder bore holds the ring
segments in place. Remove the shim stock.
10. Measure the clearance between the ring and cylinder bore at "C" Figure 4-18. Repeat
Steps 8 and 9 until all of the rings have been installed.
11. After all of the rings are in place, push the piston all the way into the cylinder; remove
the entering sleeve and connect the piston rod to the crosshead and install the outer
head following the appropriate Paragraphs in this Instruction Manual.
TP-5124
Figure 4-19. Taking End Gap Clearance (Angle Cut)
4-57
TP-5125
Figure 4-20. Taking End Gap Clearance (Step Cut)
4-15.5. Breaking in Combination Rings
Full pressure normally can be applied to the rings when they are initially placed in
service. However, on new or overhauled units, consideration of the break-in requirements of
the compressor "running gear" must also be considered. Always watch operating temperatures
for indications of overheating, especially during break-in. Refer to CHAPTER 3, OPERATION
AND TROUBLESHOOTING. If possible (pump-to-point systems only) set the cylinder lubricator
feed rate to provide maximum delivery during the break-in period. At the end of the break-in
period, the feed rate can be reduced back to normal.
4-16. PISTON ROD PRESSURE PACKING
TP-5126
Figure 4-21. Piston Rod Pressure Packing Typical Construction

4-58
Generally, all piston rods are packed with floating type packing (see Figure 4-21). There
is no adjustment or take-up for this type of packing. Tighten the flange stud nuts evenly and
squarely to obtain even crushing of the gasket at the bottom of the stuffer. Refer to the Cylinder
Instructions Sheet supplied with each cylinder for the proper cylinder bolting torque values. This
will prevent cocking of the packing cups and ensure that the packing rings are perpendicular
with respect to the piston rod.
4-16.1. Packing Rings
The packing rings are the most important part of the packing. They seal the pressure,
take the normal wear and must be serviced and lubricated. When sludge and carbon from poor
or incorrect lubricating oil have fouled them, they must be cleaned. When the rings (except
backup rings) have worn so that no end clearance exists between the segments, the rings
should be replaced. The rings are the working parts in any packing set and it is they that
require the most attention. Usually these rings have a long life, but it is a good policy to have a
set of replacement rings on hand to meet emergencies. Replacement rings may be ordered in
sets, without ordering the flange or cups.
Packing ring material and type of packing is supplied to suit each application. While it is
possible that special, non-standard packing may be encountered in the field, Dresser-Rand
currently supplies only three basic types of packing, based on the pressure application. These
are as follows:
Type I. 2750 PSI (19.0 Mpa) Packing – Water cooled
This packing is used on standard 4.75, 5.75, 6.00, 6.50, 7.00, 7.75 and 8.00-inch water-
cooled cylinders.
1 - Zero end gap cast iron pressure breaker ring.

5 - Single-acting rings comprised of one carbon-filled PTFE radial cut packing ring,
one carbon-filled PTFE step tangential cut packing ring and a third cast iron
radial cut backup ring having zero clearance at the cut.
1 - Double-acting side loaded carbon-filled PTFE wedge packing ring set composed
of two outer butt tangent cut rings, and 2 outer wedge rings with 1 center wedge
ring.
Type II. 1999 PSI (13.8 Mpa) Packing
This packing is used on standard 9.00, 9.50, 10.50, 11.50 and 12.25-inch water-cooled
cylinders.

ring.
4-59
Type III. 999 PSI (6.9 Mpa) Packing
This packing is used on standard 13.00-inch and larger water-cooled cylinders.

ring.
The PTFE ring joints are cut tangent to a diameter slightly smaller than the rod size.
These joint surfaces seal, so they must be in good condition. On some rings, the pressure side
will have radial notches. These notches must face toward the pressure when installed. The
metallic backup ring is designed to remove heat from the rod and prevent extrusion of the PTFE
rings. The backup ring has radial joints, which butt, when the ring is assembled on the rod,
leaving the ring slightly larger than the rod. No end clearance should exist at the joints, which
would permit the ring to pressure-load the rod. The joints must be smooth and butt squarely to
prevent leakage.
The outside edges only of any pair of rings should have approximately 1/16-inch (1.6
mm) radius and are normally furnished this way. Do not radius the mating (inside) edges of any
pair of rings. The faces of the rings are usually lettered or numbered on each segment of each
ring for easy identification and assembly. These identification letters or numbers must face
toward the pressure. The depth of the cup in each packing flange and the axial width of each
packing ring or ring pair should be measured using depth and outside micrometers, or a
straightedge and feelers.
The pressure breaker, Figure 4-22, is installed in the first packing cup that faces the
pressure. Its purpose is to slow down, or "break", the effects of gas pressure without totally
sealing. The type pressure breaker used is a "zero end gap" type design which has zero gap at
the joints and a 0.002-0.006 inch (0.05-0.15 mm) clearance on diameter over the rod. This ring
has pressure relief cuts in the face that is towards the pressure.
TP-4414-B
Figure 4-22. Zero End Gap Pressure Breaker
4-60
Both single acting (Figure 4-23) and double acting (Figure 4-24) rings are free to float
(move axially and vertically with the piston rod) in their respective cups.
TP-5127
Figure 4-23. Single-Acting PTFE Packing Rings with Metallic Back-Up
TP-5128
Figure 4-24. Double-Acting PTFE Wedge Packing Rings
SERVICE NOTE
Clearances should be as those listed in Table 4-4. If the

measured clearance is outside of the limits shown, refer the
problem to the Dresser-Rand Gas Field Compressors
Customer Service Group Tulsa, OK before re-machining either
the packing rings or flange cups.
4-61
Table 4-4. Packing Clearances
Ring Axial Clearance Axial Clearance Maximum

Material Cast Iron Cups Steel Cups Radial Clearance
Inch (mm) Inch (mm) Inch (mm)
Carbon Filled 0.011 - 0.015 0.020 - 0.024 0.060

PTFE (0.28 - 0.38) (0.51 – 0.61) (1.50)
4-16.2. Packing Gasket
Next in importance to the packing rings is the end gasket. Keep the gasket surfaces
clean and dry. No matter how perfectly the packing rings seal around the rod, if the end gasket
leaks, the pressure forces the gas to bypass the rings by leaking around the case into the area
between the case and the bore and then to the atmosphere. The packing flange stud nuts must
be tightened evenly to ensure a proper seal of the gasket at the front end of the packing and to
ensure complete closure of the ground/lapped joints on the packing cases. The packing rings
have been given sufficient side clearance so that normal tightening will not pinch the packing
rings in their grooves.
After a short period of operation, soft gaskets should be re-tightened to take up any
additional deformation caused by the working pressure on the packing.
Spare gaskets should be carried in stock and a new gasket installed each time the
packing case is removed. This prevents forced shutdowns due to leaks occurring after the
cylinder is pressurized.
4-16.3. Packing Cases
The cases are made up of cup-like sections. The joints are ground and/or lapped. Each
contacting surface must be cleaned of dirt and lint and inspected for scratches and burrs before
assembling. The mating surfaces must occasionally be lapped to maintain a tight seal. To do
this, lap the cup to a surface plate after making sure that the surface plate is in good condition.
On packing assemblies that are designed for internal water cooling, small O-rings are used
between the cups. See the instructions, which follow in the next paragraph concerning the
proper installation of these seal rings.
4-16.4. Installing the Packing
The packing should not be installed until the unit is ready to start, since the rings may
corrode the piston rod where they rest on it. The cup sections are held together by tie rods
which are screwed into tapped holes in the nose piece (end cup) of the packing, and are held
on the outer end by nuts on the face of the flange. Become acquainted with the construction of
the packing you are about to install. Learn how it will go into the cylinder, and know the proper
location of each cup and ring set. Note the location of vent cups, oil cups and cooling water
cups and gaskets, if used. Pay particular attention to the rings located in each cup and know
how they are assembled and which side faces the pressure. Before any packing is taken apart,
it is recommended that each cup and the flange be stamped in numerical sequence so they can
be reassembled in their original positions.
4-62
1. If the compressor piston and piston rod have previously been installed in the cylinder,
unscrew the piston rod from the crosshead and move the crosshead away from the
piston rod.
2. If the oil scraper packing was previously installed, disassemble and remove the scraper
rings as described in Paragraph 4-17 in this Instruction Manual.

3. After marking the outside of the packing cups (on a non-critical surface) in numerical
sequence as discussed previously, disassemble the packing cups and rings; be careful
not to lose any gaskets, ring segments or garter springs. Lay the packing components
out on a clean surface in the order removed. Clean all the parts with a safety solvent.
Be sure that there is no dirt, chips or other foreign matter in the oil or vent passages that
can be carried into the packing during operation or obstruct the flow of oil into the
packing.
4. Thoroughly clean the piston rod and packing cavity in the frame end of the cylinder.
Make certain that the piston rod is not scratched, nicked or otherwise marred where it
will operate inside the packing.
5. The packing cups should be disassembled and the rings taken apart when the packing
is installed (this also applies when the packing is being removed or when it is necessary
to pull the piston rod). It is not a recommended practice to attempt to slide the packing
rings over the end of the piston rod, unless an entering sleeve is used, because the rod
threads can nick or otherwise damage the rings.
6. New packings come assembled with the correct type of rings in their proper grooves and
in the proper relation to one another. All the rings must be reassembled in their original
positions or they will not function correctly. Refer to the previous instructions in
Paragraph 4-16.1 on the proper assembly orientation of the packing rings.
7. Slide the end cup (or nose cone) over the end of the piston rod and assemble its
packing ring(s) over the rod by first fastening the garter spring around the rod and then
inserting the ring segments, one at a time, under the spring. Be sure the rings are
assembled exactly in their original positions with all the segments in the correct relation
to each other and with the correct side facing the pressure. Be sure the dowels and
dowel holes are lined up between ring pairs. On non-lubricated service, slide the rings
into their cups. On lubricated service, lubricate the rings generously with oil and then
slide them into their cups.
4-63
SERVICE NOTE
For packings having O-rings between the cups, as is the case with
water-cooled packing assemblies, be sure that the O-rings are
correctly located in their grooves before tightening the tie rod nuts.
A thin coating of grease (or a silicone type lubricant) on the O-rings
aids in keeping them in the grooves prior to tightening the
assembly. As the O-rings can be easily damaged, it is a good
practice to carry sufficient spare sets and to replace them each time
the packing is dismantled.
8. Continue with each packing cup and ring arrangement in sequence, sliding the cups
together over the tie rods. Slide the flange into position being certain that all of the cups
are evenly centered around the piston rod. Then tighten the tie rod nuts.
9. Make certain the gasket on the end cup is in good condition and clean. Oil the rod only
if lubricated packing is being used. Slide the packing assembly into place in the frame
end of the cylinder. Center the packing with respect to the piston rod and then
assemble and tighten the packing flange stud nuts evenly to assure the end gasket is
evenly compressed. If this gasket is not properly seated, leakage can occur around the
end cup.
10. Recheck the gap between the piston rod and packing flange at several points around
the circumference of the rod. The possibility of the rod dropping slightly because of
piston ring wear must be given due consideration.
Should the rod contact the packing flange or cups during

operation, damage to the rod is almost certain to result.
11. The packing rings are free to float in their cups (assuming they have proper side
clearance) regardless of the stud tightening forces. The packing cups are designed to
transmit uniform stud pressure through the joints without deflection. Like any gasketed
joints, the packing stud nuts must be periodically tightened.
12. Install the oil scraper rings per Paragraph 4-17 and then attach and adjust the piston rod
in the crosshead per Paragraph 4-13 found in this Instruction Manual.
13. When the machine is started, oil the packing rings and piston rod generously only on
lubricated units until the rings wear in. The packing may leak slightly while creating a
satisfactory fit with the rod; however, the packing should not blow profusely during
break-in. Should severe leakage (blowing) occur, the compressor must be immediately
shut down and the packing dismantled to determine the cause. Abnormal leakage can
also be caused by dirt or chips cutting the rings, an improper grade (or too much)
lubricating oil in the sump, or inadequate side clearance of the rings in their cups.
4-64
4-16.5. Packing Operation and Maintenance
After installing a new packing or set of renewal rings, start the compressor up with no
load in the same manner as breaking in a new unit. On lubricated units, feed two or three times
the usual amount of oil to the packing while it is wearing in. The oil that works out along the rod,
or through the packing vent, should be checked frequently. If the oil remains clear, it is a good
indication that the packing is wearing in properly. During break-in of higher-pressure packings
(over 1000 PSIG or 6900 kPa), the oil normally will become darker and show some wear
particles; however, the oil should not become black. Should the oil become black (indicating
premature wear), or should blow-by be excessive, the cause may be a too rapid of increase in
the load or pressure on the packing. Often, by reducing the load slightly and running for a short
period of time, the oil will clear up to the point where the load can then be increased again.
Because there are so many variables (such as temperature, pressure, type of lubricant,
material, gases being handled, etc.), there are no hard and fast rules set for the allowable rate
of increase in pressure while breaking in a new packing. With filled Teflon® packing rings, the
break-in time is normally much shorter than with metallic rings. Often, the break-in time with
this ring material is a matter of minutes, and the load may be increased rapidly. Watch the
piston rod and packing temperatures carefully to avoid excessive heat buildup in the packing
during the rapid break-in.
During operation, the packing leakage may become progressively worse over a period of
time. This indicates the packing is faulty and it should be inspected as soon as possible.
Operation of the unit with excessive packing leakage will result in abnormal wear of the packing
rings or piston rod.
4-16.6. Inspecting the Packing
Periodically, the packing should be removed for inspection and cleaning. In removing
the packing, take care to avoid damage to the gasket or to any surface that makes a pressure
tight joint. Do not use a chisel or sharp instrument to open any joint between the packing cups.
In the inspection of packing rings, wire edges may be found around the bore of the rings if
considerable wear has occurred. Remove these wire edges with a file. However, do not break
the corners where any two surfaces of packing rings match and do not disturb the bore of the
rings except to remove the wire edges. Wash the springs clean of carbon and sludge. If the
springs have lost their tension, replace them. Observe the clearance between the ends of the
segments of the wearing rings. As long as some clearance is present, the rings may be re-
used. However, when the rings have worn to the point where the ends butt, they should be
replaced.
4-16.7. Replacing the Packing
In replacing the piston rod packing, take care to tighten the flange nuts evenly, while
checking with feelers in the space between the rod and the packing flange. Make sure the
clearance is equal all the way around the rod. Make sure the rod-packing flange does not touch
the piston rod, as the rod and the packing can be seriously damaged. When ordering parts or
inquiring for additional information regarding the packing, always give the serial number
stamped on the end of the case, along with the cylinder size and the cylinder serial number.
4-65
4-17. PISTON ROD OIL SCRAPER RINGS
A stuffer is bolted to the frame end of the cylinder yoke. It contains a set of oil scraper
rings with a flange, and prevents the frame oil from being carried out of the frame along the
piston rod. The rings also reduce the possibility of cylinder gases and cylinder lubricating oil
from entering the frame and possibly contaminating the frame lubricating oil.
Current stuffer and oil scraper ring arrangements are illustrated in Figure 4-25. Some
distance pieces are equipped with a set of double acting (Type BD) seal rings located in the
gland closest to the cylinder. For those applications requiring a purged distance piece (2)
standard sets of (3) 3RWS rings are used. This helps to seal the distance piece.
TP-5129
Figure 4-25. Piston Rod Oil Scraper Packing
Metallic oil scraper rings must be disassembled and the rings

taken apart when they are being removed or installed. Do not
attempt to slide the rings over the end of the piston rod
because the threads can nick the rings and permanently
damage them.
Before starting the unit for the first time, wipe out the stuffers and clean the piston rods.
Take care to keep a smooth bearing on the rod, as nicks or dents in the rings or scores on the
rod will prevent a tight seal.
Oil scraper rings normally require little attention except for periodic cleaning which is
determined by the operating conditions. Inspect the rings for wear by checking the end
clearance after slipping the rings over a mandrel the same diameter as the piston rod. When
the rings have worn sufficiently to butt the ends, it is best to replace them.
4-66
Renewal oil scraper rings are furnished in sets. The ring segments are usually
numbered and adjacent segments must match. With the current design shown in Figure 4-25,
the radial cut grooves on the scraper rings should face the cylinder and the flat faces of the
rings should face the crosshead. The packing rings can face either direction.
Use the following Steps to install replacement oil scraper rings in the unit:
1. Unscrew the piston rod from the crosshead, then back the crosshead away from the
piston rod and remove the stuffer from the yoke.

2. Disassemble the rings and lay the parts on a clean surface. Note the identification
marking on each segment of each ring. Clean the parts thoroughly with a safety
solvent.
3. Make certain that the piston rod is clean and free of nicks or burrs. If any are found,
these should be carefully removed with a file and the rod polished using a fine emery
cloth.
4. Clean the stuffer thoroughly and install it in the yoke. Be sure a gasket is placed
between the stuffer and yoke mounting surfaces. Bolt the stuffer securely in place.
5. Place the ring flange on the piston rod and then assemble the oil scraper rings over the
rod; the flat sides of the rings face the crosshead. First fasten the garter springs around
the rod, and then place the ring segments under the springs, making sure to match the
segments according to the letters or numbers stamped on them.
6. Move the flange into position over the rings. The flange is designed to provide 0.002 to
0.004 inch (0.05 to 0.10 mm) total end clearance for the scraper rings. Check this
clearance before securing the flange. If the clearance is insufficient for the rings to
"float" on the rod, they will not function properly. Make sure the drain holes in the flange
are at the bottom, then attach the flange to the stuffer; tighten the flange capscrews
evenly. Check to be sure that the flange is centered around the piston rod. Avoid any
possibility of the rod touching the flange or stuffer as the rod, flange and rings may be
damaged if this happens.
7. Liberally oil the scraper rings before starting the compressor when new rings have been
installed. The oil from within the frame will then keep the rings lubricated during normal
operation and subsequent starts.

pressure before barring. Failure to depressurize the
compressor cylinders prior to barring may result in unexpected
rollover that can cause personal injury.
4-67
Failure to heed this WARNING can result in a fatal accident if
the unit rolls over unexpectedly.
SERVICE NOTE
When the compressor is shut down for a long period and the piston
rod packing and the oil scraper rings are not removed, bar over the
compressor once every 24 hours to distribute any oil held in the
packing and to prevent localized corrosion of the piston rods.
4-18. BALANCE CYLINDER (If Used)
TP-5130
Figure 4-26. Balance Cylinder
A balance cylinder (Figure 4-26) is supplied on those compressors where less than a full
complement of cylinders is required (for example, a four-throw unit using only three cylinders).
The balance cylinder mounts directly on the frame extension and utilizes a piston rod and
balance piston that is similar to a conventional compressor piston and piston rod for
disassembly and assembly purposes.
4-68
To remove the balance cylinder, disconnect the lube supply tubing and drain piping.
Take out the capscrews that hold the end plate in place, then remove the cover to expose the
cylinder bore. Unscrew the balance piston rod from the crosshead and pull the piston and rod
out through the bore. Support the balance cylinder and then remove the capscrews and locking
rings that hold the cylinder onto the frame extension. Finally, remove the cylinder and O-ring.
Replacement of the balance cylinder is the reverse of the removal Steps.
NOTE
When installing the balance piston assembly ensure that the
piston rod is threaded into the crosshead a minimum of 1.5
times the piston rod thread diameter. The balance piston should
be approximately centered in the balance cylinder bore at mid-
stroke. The balance piston should also be in a vertical position
within the balance cylinder bore to within 5 degrees. The balance
piston to bore clearance should be .013”-.019”.
4-19. COMPRESSOR VALVES
The "PF Type" valve, a high-speed ported plate valve of Dresser-Rand design, is used
as the standard valve in HOSS cylinders. These instructions cover only the PF valve. If other
types of valves are used, then the supplemental instructions for those valves must be consulted.
The valve consists of a seat, stopplate, closing springs and a valve plate. The valve is held
together by a center capscrew. A gasket is used under the stopplate on inlet valves and the
valve seat on discharge valves where they seat in the cylinder gas passage, preventing gas
leakage past the valve. A typical inlet valve is shown in Figure 4-27, while a typical discharge
valve is shown in Figure 4-28. The seat and stopplate have polarized diameters on the nose of
the valve to help ensure that the valves are positioned correctly in the cylinder.
TP-5131
Figure 4-27. Typical "PF Type" Inlet Valve

4-69
TP-5132
Figure 4-28. Typical "PF Type" Discharge Valve
4-19.1. Description of Operation
A compressor valve acts as a check valve in the inlet and discharge passages to the
cylinder bore. The inlet valve allows the gas to enter the cylinder on the suction stroke and then
closes to prevent back flow of the gas into the inlet gas passage on the discharge stroke. The
discharge valve opens to allow gas to leave the cylinder on the discharge stroke and then
closes to prevent the gas in the discharge passage from re-entering the cylinder on the suction
stroke.
Compressor valves are opened by differential pressure across the valve. The valve
plate moves off its seat and is guided into the stopplate recess by the guide ring when opening.
As the piston nears the end of its stroke, pressure across the valve starts to equalize. At this
point, the springs start to move the valve plate toward the seat. A combination of spring load
and differential pressure will hold the inlet valve closed on the discharge stroke and the
discharge valve closed on the suction stroke.
4-19.2. Valve Maintenance Recommendations
1. To obtain maximum efficiency from a compressor cylinder, the inlet and discharge
valves must be clean and tight. The valves and cylinder gas passages must be
periodically examined and thoroughly cleaned wherever dirt is evident. Operating
experience will dictate both the length of time between valve inspections and the valve
maintenance cycle. At start-up, check the valves during break-in at least once, then one
week after start-up or more frequently if the gas being handled is known to be dirty. If
the valves are found to be particularly dirty, locate and eliminate the cause. See Item 2
for a suggested MINIMUM maintenance schedule.
4-70
2. We recommend the following valve inspection and maintenance schedule as a

MINIMUM:
 Prior to initial start-up and EVERY TIME valve or unloader maintenance is
performed.
 At least ONCE during the break-in period.
 One week after start-up (including after valve or unloader maintenance or after
overhauls).
 Once a month thereafter for three months.
 Once every three months thereafter for a full year.
 Once each year thereafter, or as conditions dictate.
3. The center setscrews used with unloaders, and all other valve fasteners, particularly the
stud nuts that secure the valve cover, MUST be properly tightened to the torque values
given in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-3 of this
Instruction Manual. DO NOT USE AN IMPACT WRENCH ON ANY VALVE
FASTENER.
4. Never attempt to tighten fasteners on a compressor cylinder, including the valve or

unloader setscrews, while the compressor is running or with the cylinder pressurized.
This practice is extremely hazardous, and can result in a life-threatening accident
should a stud or bolt break during the tightening process.
5. Always make sure there is no residual gas pressure in the cylinder bore or passages
before removing the valve or unloader covers.
6. Venting of hazardous gases must be performed in accordance with established safety

practices at the installation site.
7. The importance of keeping accurate valve maintenance records cannot be

overemphasized. Record all valve failures, the cylinder and location on that cylinder,
the type of damage and any other data that may be helpful in finding a trend.
8. To eliminate dirt found in the compressor valves, a suitable intake filter or scrubber
should be installed and properly maintained. Experience will dictate the filter or
scrubber maintenance cycle.
9. Cylinder lube oil in excess of the amount required to properly lubricate the cylinder bore
and valves is detrimental to valve life. The oil feed rate of the cylinder lubricator (with
pump-to-point systems) can be reduced to eliminate excess lubrication based on the
condition of the cylinder gas passages, valves and cylinder bore. On inspection, the
valve should have a greasy appearance, but not have oil droplets showing. Shortened
valve life often results from using oil with improper viscosity or poor quality, or delivery at
the improper feed rate. Recommendations for selecting a cylinder lubricating oil are
given in CHAPTER 2, LUBRICATION. These recommendations should be reviewed
with a reputable oil supplier to determine the best oil for a particular application.
10. All compressor valves should be inspected for leakage (which may result in abnormally
high temperatures). In addition, the cylinder cooling water system (if used) should be
examined for general cleanliness and obstructions to ensure the proper quantity of
coolant at the required temperature is available. Periodic cleaning of the cylinder water
4-71
passages may be required.
11. Liquids in the gas stream can wash or dilute cylinder bore lubricating oils, causing rapid
wear and early failure of the valve (and cylinder) parts. A slug of liquid can cause a
failure of the valve plates or, in severe cases the valve seat. Some "wetness" in the gas
stream often can be dealt with by the selection of a suitable lubricating oil. With very
wet applications, adequate separators should be located close to the cylinders. Also, it
is important that the cylinder inlet piping be arranged without low spots where liquid can
accumulate.
12. Mark or tag valves with the following minimum information as they are being removed
from the cylinder. This information will be useful when troubleshooting valve problems
and will help prevent the intermixing of valve parts, when more than one valve is
disassembled.
 Compressor Serial Number....
 Cylinder Serial Number....
 Inlet or Discharge Valve....
 Cylinder location - Frame or Outer end....
 Hours of Operation.
13. Special materials and manufacturing methods are used such that only genuine Dresser-
Rand parts should be used. The reconditioning procedures given in these instructions
are valid only when genuine Dresser-Rand parts are being used.
14. Carefully check the part number of new parts against the specified valve parts list.
15. Never change the valve lift.
16. The valve seat may have to be reconditioned as described in Paragraph 4-19.5.
17. A new valve plate must be used if the valve seat has been reconditioned.
18. Never turn (invert) the valve plate over. Always replace the valve plate and recondition
the seat.
19. When handling valve assemblies or parts, take care not to contaminate the items.
4-19.3. Removing the Valves – O-Ring Valve Cover
The current standard valve cover design used with HOSS cylinders is the O-ring cover
design, as illustrated in Figure 4-29. When removing an inlet valve from a location where an
unloading device is also being used in conjunction with the valve as a means of capacity
regulation, refer to the applicable unloader instructions found latter in this Instruction Manual
first before removing the valve.
4-72
TP5133
Figure 4-29. O-Ring Seal Type Valve Cover Arrangement
Observe the safety precautions (Paragraph 4-2 in this

Instruction Manual) before attempting to remove a compressor
valve. It is particularly important that ALL PRESSURE is
released from the cylinder passages and piping before pulling
valve covers. CAREFULLY CRACKING OPEN drain valves on
inlet and discharge manifolds is a good method to determine if
any pressure exists in the cylinder bore, cylinder passages and
piping. INJURY TO PERSONNEL CAN OCCUR IF THESE
PRECAUTIONS ARE NOT STRICTLY OBSERVED. Whenever
compressor valves have been removed, it is extremely
important that the inlet and discharge valves be correctly
reinstalled back into the cylinder. INCORRECT ASSEMBLY
CAN CAUSE AN EXTREMELY HAZARDOUS CONDITION,
WHICH CAN RESULT IN SEVERE DAMAGE TO THE
COMPRESSOR AND INJURY OR DEATH TO THE
OPERATING/MAINTENANCE PERSONNEL.
4-73
With the O-ring body seal used on this type valve cover, any
pressure that may be left in the cylinder will not be released
when the cover nuts are loosened, but will remain under the
cover trapped by the O-ring. To prevent the possibility of the
valve cover being "blown off" by residual pressure when the
cover nuts are removed, two longer studs are required to
permit the safe removal of the cover. These studs are either
present (they are double nutted if factory supplied) or should
be fabricated at the site. FAILURE TO OBSERVE THE
FOLLOWING VALVE REMOVAL PROCEDURE CLOSELY CAN
RESULT IN POSSIBLE PROPERTY DAMAGE, INJURY OR
DEATH TO THE OPERATING/MAINTENANCE PERSONNEL.
1. Mark or tag the valves and valve holes as the valves are removed to ensure that they
are returned to their original locations.
2. Locate the two longer studs; these are diametrically opposed across the valve cover bolt
pattern. If such studs are not installed, then fabricate two studs and install them (with 2
nuts on each stud) 180 degrees apart before loosening or removing any other stud nuts.
3. Evenly loosen all the valve cover stud nuts. Remove only those nuts on the short valve
cover studs. At this point, the nuts on the long studs are securing the valve cover.
4. Equally loosen the nuts on the long studs two turns at a time. As the stud nuts are
loosened, it may be necessary to tighten down the valve cover jackscrews (if so
equipped) or to carefully pry under the valve cover to keep the cover in contact with the
stud nuts. This will prevent the sudden loosening or blowing off of the valve cover when
the O-ring breaks free of the valve passage. As the O-ring is slowly pulled free of the
valve passage, any residual pressure will be safely vented from under the cover.
SERVICE NOTE
A retaining setscrew in the side of the valve cage is used to hold the
valve and cage in a valve hole located in the bottom half of the
cylinder. However, care still must be exercised when removing the
valve cover so that the valve does not fall out should the setscrew
not hold.
5. Remove the valve cover.
6. Larger valves have two tapped holes in the discharge seat, or inlet stopplate, on the
face toward the cylinder bore. To simplify this valve removal when the valve is located
in the bottom half of the cylinder, first remove the top valve that is located 180 degrees
opposite the bottom valve being removed. Then, working through the top valve port,
(the compressor piston must be positioned so that it does not interfere with this
operation) screw a threaded rod into the tapped hole in the bottom valve. The valve and
cage assembly then can be supported from above while the valve cover is removed.
4-74
SERVICE NOTE
If the compressor valve is stuck in the cylinder, striking edgewise on

the valve crab with a wood block or soft metal bar (to prevent
damage to the cage or valve) can jar it free. Do not use a hammer
on the cage.
7. Loosen the retaining setscrew from the valve cage, then carefully remove the valve
cage and valve from the cylinder. Remove the valve seat gasket that is located under
the valve. This gasket should not be reused. Always install a new gasket when re-
installing the valve. Most valves are attached to the valve cage with two capscrews or
machine screws to facilitate handling. To separate the valve from the cage, remove
these fasteners.
4-19.4. Disassembling and Servicing the Valve
If the valve must be held in a vise, do not clamp the valve

tightly enough to cause distortion. Distorting the valve will
render it useless.
1. Place the valve in a valve holder. See Figure 4-30 for a suggested design for a valve-
clamping fixture.
TP-4253
Figure 4-30. Valve Clamping Fixture

4-75
2. Remove the capscrew that fastens the valve together. DO NOT allow the stopplate to
turn in relation to the valve seat. To do so may shear the locating pins.
Care must be taken when disassembling these valves to

ensure that the valve plates and springs do not become
intermixed. Failure to follow this caution will result in the
incorrect loading of the various plates, resulting in premature
valve failure. Even when the valves are of the same type (inlet
or discharge) and of the same size, the components of the
various valves must not be intermixed. This is because each
valve has established its own wear pattern and sealing surface,
which will not function in another valve. Failure to follow this
caution will result in the incorrect loading of the valve plates,
valve leakage and premature valve failure.
3. Very carefully, separate the stopplate and valve seat. Note the position of all valve
internals; do not allow them to become intermixed. Remove the closing springs and
place them in a separate location. Identify each spring so that it can be returned to the
same spring hole.

when storing, handling or using solvents.
4. Clean all of the parts. (Soaking the valve parts overnight in safety solvent followed by a
stiff brushing or light scraping will aid in the removal of carbon.) Brush the parts with a
soft wire brush to remove stubborn deposits, but use a soft bristle brush only on all
seating surfaces.
5. Rinse the parts in clean solvent. Then thoroughly dry the parts using clean dry
compressed air.
SERVICE NOTE
Replace the valve plate if the ring depth is greater than 0.010 inch
(0.25 mm). However, it is recommended to use a new valve plate
each time the valve is rebuilt.
6. On the valve plate, there will be annular rings worn in by the valve seat, these are
normal. Check the rings for uniformity of contact. Any dull or uneven contact is an
indication of improper seating. Do not grind or invert the valve plate to obtain a new
seating surface. Replace the plate with a new one.
4-76
7. Examine the valve seat for cracks, nicks, burrs, scoring, steps, leakage paths and other
signs of defects. The valve plate seating area (rings) on the valve seat should be very
bright and evenly polished. Check the rings for uniformity of contact. Any dull or
uneven contact is an indication of improper seating.
When rebuilding a valve, always renew the seating surfaces.

That is, provide a new valve plate when a new or reconditioned
valve seat is used. Likewise, when a new valve plate is
required, a new or refaced valve seat must also be provided.
Failure to follow this caution will result in leakage and early
valve failure.
8. The valve seat can be re-machined to correct for wear or minor defects to the seating
surfaces. The valve seat reconditioning operations are described in detail in Paragraph
4-19.5 that follows. An excessively worn or damaged seat must be replaced.
9. Check the valve springs for cracks, pits or set (set is determined by measuring the free
height of a used spring against the height of a new one). Also, check for weakness by
comparing the used spring against a new one with the same part number. If any are
found to be defective, replace all the springs with new ones. It is also recommended to
use new springs each time the valve is rebuilt regardless of the condition of the springs.
10. Examine the stopplate for wear and damage. The stopplate can be re-machined to
correct for wear or minor defects. The stopplate reconditioning operations are
described in detail in Paragraph 4-19.6 that follows. An excessively worn or damaged
stopplate must be replaced.
4-19.5. Reconditioning the Valve Seat
Valve seats, which have become worn or damaged, can be resurfaced provided that
certain dimensional limits are not exceeded. Refer to the Valve Reconditioning Data Sheet
provided for the dimensions for each valve. Every “PF Type” valve has its own individual
reconditioning sheet.
A valve seat can be re-machined as indicated below without affecting the valve's
performance (see Figure 4-31 for dimensional locations):
Refer to the Valve Reconditioning Data Sheet for the minimum

allowable seat thickness. The seat must be replaced if the
thickness is less than the minimum. Also, be certain that any
re-facing extends over the entire seating surface.
4-77
TP-4265-D
Figure 4-31. Critical Valve Seat Reconditioning Dimensions
When reconditioning the valve seat, the land width (s) is to be maintained at 0.025 to
0.050 inch (0.63 to 1.20 mm). If the land width exceeds this value, the mud grooves between
the ports (b) must be machined to obtain the original land width. In addition, the depth of the
mud grooves (a) should be maintained at 0.031 inch (0.79 mm) and a full radius must be
maintained where the mud groove meets the land. Moreover, a 0.005 to 0.015 inch (0.13 to
0.39 mm) chamfer edge must be maintained on each land where it meets the port. The port
width (b) must not be increased beyond the factory dimension. Surface finish must also be held
to at least 16 Ra.
4-19.6. Reconditioning the Stopplate
Machining of the stopplate is usually not required during a valve overhaul. If an

inspection reveals minor damage to the stopplate, the defective part can be re-machined
provided that certain dimensional limits are not exceeded. Refer to the Valve Reconditioning
Data Sheet provided for the dimensions for each valve. Every “PF Type” valve has its own
individual reconditioning sheet.
If the locating pins are damaged, pull them out. If the locating pins cannot be pulled out,
then gently push the pin through the locating pin hole that is drilled through the stopplate.
A stopplate can be re-machined as indicated below without affecting the valve's

performance (see Figure 4-32 for dimensional locations):
4-78
TP-4266
Figure 4-32. Critical Stopplate Reconditioning Dimensions
The stopplate can be reconditioned provided that the counterbore depth (T) is
maintained and the maximum removal from the stopplate is 0.031 inch (0.79 mm). If the
counterbore depth is not maintained, then the valve lift will be altered. The correct counterbore
depth is equal to the guide ring height +0.002 inch / -0.000 inch (+0.05 mm / -0.00 mm).
Furthermore, the original spring hole depth must be maintained to within a tolerance of +/-0.010
inch (+/-0.26 mm). Therefore, if the stopplate counterbore is re-machined, the spring holes
must be re-machined by the same amount. Refer to the Valve Reconditioning Data Sheet for
the correct counterbore and spring hole depth.
4-19.7. Assembling the Valve
1. If removed, reinstall the locating pins flush with the top of the stopplate rim.
2. If not already cleaned, clean the internal threads in the valve seat/stopplate and the
external threads on the center capscrew.
3. Place the stopplate on a clean, flat surface with the locating pins up.
4. Place the valve springs into the spring holes in the stopplate. Ensure the springs are
inserted into the same holes from which they were removed. If new springs are being
installed, refer to the parts list for proper identification.
5. Install the valve plate orientating the holes to the locating pins in the valve seat. If a
used plate is being reinstalled, ensure that its seating surface matches the valve seat.
New valve plates should be used with new or re-machined seats. When installing the
valve plate, ensure that the ports in the valve plate line up with the ports in the stopplate.
It is possible to incorrectly install the valve plates in certain valves if care is not
exercised.
6. Fit the valve seat to the stopplate. Apply an anaerobic adhesive primer to the threads
and allow it to dry for 5 minutes. Apply Loctite® 242 Threadlocker (two drops only) to
the external threads of the capscrew and install it finger tight. On discharge valves, it is
necessary to carefully turn the valve over to install the capscrew.
4-79
7. Place the valve in a holding fixture. A typical valve holder is shown in Figure 4-30.
When tightening the capscrew, DO NOT allow the stop plate to

rotate with relation to the valve seat. If this is allowed to
happen, it may shear the locating pins.
8. Torque the capscrew to 25,000 PSI (172 Mpa) pre-stress following the tightening
instructions found in Paragraph 5.3 located in CHAPTER 5, GENERAL DATA AND
SPECIFICATIONS in this Instruction Manual. DO NOT allow the stopplate to turn in
relation to the valve seat as this may shear the location pins.
9. Check for the free movement of the valve plate by pushing on it with a rigid but soft
instrument made out of wood or plastic that will not scratch the valve plate.
4-19.8. Installing the Valves – O-Ring Valve Cover
When installing an inlet valve in a location where an unloading device is also being used
in conjunction with the valve as a means of capacity regulation, refer to the applicable unloader
instructions first before installing the valve.
Whenever compressor valves have been removed, it is

extremely important that the inlet and discharge valves be
correctly reinstalled back into the cylinder. INCORRECT
ASSEMBLY CAN CAUSE AN EXTREMELY HAZARDOUS
CONDITION, WHICH CAN RESULT IN SEVERE DAMAGE TO
THE COMPRESSOR AND INJURY OR DEATH TO THE
OPERATING/MAINTENANCE PERSONNEL. The type "PF"
valve is always placed in the cylinder with the head of the
capscrew located AWAY from the cylinder bore. Fasten the
valve cage or unloader cage to the valve first, when possible,
to ensure that the valve is not reversed at installation. IF IN
DOUBT as to whether a valve is inlet or discharge, or as to
which cylinder holes receive an inlet or discharge valve,
CHECK WITH YOUR SUPERVISOR.
1. Prior to installing the valve, check to see that the seating surfaces on the valve
assembly, valve cover and the cylinder valve hole are smooth and clean. If any
evidence of defective seating surfaces are found, use the following Steps to ensure the
proper valve installation:
A. Place lapping compound on the gasket seating surface of the valve and
place the valve in the valve hole without using the seat gasket. Lap the
valve and valve hole gasket surfaces to obtain at least 95% contact area, as
evidenced by “bluing” or an equivalent method.
4-80
B. Remove the valve and clean both it and cylinder valve hole thoroughly with
soap and hot water to remove all the traces of the lapping compound.
Solvent will not remove the lapping compound no matter how clean the
surface appears to the eye.
SERVICE NOTE
Valves and cages must be returned to the same valve holes from
which they were removed. The threaded rod used to facilitate
handling large valves, as described previously in the valve removal
procedure, also may be used to assist in the valve and cage
installation.
2. Install a new valve seat gasket, and then install the valve and cage in the cylinder valve
hole. This task is made easier if these parts are fastened together with machine screws
and lockwashers before installation. Be certain the valve seats firmly on the ledge in the
cylinder and rests squarely on the valve seat gasket.
3. On the bottom half of the cylinder, the valve and cage assembly is held in the valve hole
by a retainer, normally a setscrew through the side of the valve cage on this valve
design. Install the setscrew with an Allen wrench to hold the valve and cage in place
until the valve cover can be installed.
4. Place a new O-ring in the valve cover body groove. A light coat of a silicone lubricant or
other lubricant compatible with the O-ring material and process applied on the O-ring will
facilitate its entry into the cylinder valve hole.
5. Place the valve cover over the valve hole. Watch the cover O-ring as it enters the valve
hole to be sure it is not rolled out of its groove. Install the stud nuts.
Tightening of the valve cover stud nuts is critical. Under

torquing will result in the loss of sealing capacity between the
valve seat gasket and the valve seat and the possible
loosening of the valve cover during operation with the
possibility of releasing process gas. Over torquing will result
in excessive stresses and loads being imparted to the valve,
valve cage and cylinder seating ledge. It is imperative that
when using the "TIGHTENING REQUIREMENTS" instructions in
CHAPTER 5, GENERAL DATA AND SPECIFICATIONS
Paragraph 5-3, the proper pre-stress column in the chart is
selected. Go to the column header in the torque table for the
pre-stress required. Then move down the column to the correct
fastener size to obtain the proper torque value. This torque
value only applies when the specified thread lubricant is used.
6. Tighten the valve cover stud nuts alternately across the bolt circle to ensure that the
cover is drawn down squarely. We require that this tightening progress be in
4-81
incremental stages rather than applying the full torque on the initial tightening. The
required torque value is listed in CHAPTER 5, GENERAL DATA AND
SPECIFICATIONS Paragraph 5-3 of this Instruction Manual.

The operator must insure the driver will not start either by
engine-driven units or by insuring that power cannot be turned
7. After all of the valves are installed, bar the compressor through at least one complete
revolution to be certain there is no interference between any moving parts.
Never tighten the valve cover stud nuts while the compressor
is in operation or pressure exists within the cylinder. A life-
threatening release of gas or an explosion can occur if a stud
breaks during the tightening operation.
8. The compressor now may be started in the normal manner.
Use extreme caution when checking the valve covers. The

discharge valve cover can experience temperatures in excess
of 250°F (121°C). Touching a valve cover with an unprotected
hand can cause severe burns. We recommend the use of a
contact thermometer for checking temperature and a
stethoscope for checking noises.
4-82
9. After the cylinder has reached operating temperature and pressure, shut down the
compressor and relieve all the pressure in the cylinder. Check the tightness of the stud
nuts on all the valve covers. If required, re-torque the valve cover stud nuts as
described previously.
10. At regular and frequent intervals (as established by operating experience) check the
valve covers for looseness by using a stethoscope on the valve cover to listen for
pounding or knocking of the valve cage against the cover while the compressor is
operating. Any pounding or knocking indicates that the valve is loose. A loose valve
may break apart and drop into the cylinder bore, causing serious damage to the
compressor.
4-20. REGULATION DEVICES
Regulation devices can be of two basic types: the inlet valve unloader or the clearance
pocket (either fixed volume or variable volume). Instructions for both of these basic types of
devices follow. These instructions cover only the basic, standard type of regulation
devices. Some design differences are to be expected due to special operating requirements
and these variants will undoubtedly be encountered in the field from time to time. Refer any
questions regarding the unloaders or clearance pockets to your nearest Dresser-Rand service
representative.
Regulation devices when activated or adjusted affect the

performance of the compressor. Unloading sequences not
initially approved or reviewed can lead to overloads, non-
reversal, overheating, and/or valve reliability problems.
Consult with a Dresser-Rand representative if such unloading
sequences have not been approved.
4-20.1. Unloaders - Inlet Valve and Clearance Pocket
SERVICE NOTE
The instructions that follow are based on a typical Dresser-Rand

unloader design. Refer to the job-specific cylinder parts list located
in the PARTS LIST section of the unit Service Manual to determine
the type of unloader supplied and the actual arrangement of parts.
Three types of Dresser-Rand unloaders are available as described later in this section:
1) Port, 2) Plug, and 3) Clearance Pocket. An Inlet Valve Unloader (See Figure 4-34) is used
on a compressor cylinder inlet valve to render the valve inoperative. A Clearance Pocket
Unloader (See Figure 4-34) is used to add clearance to the cylinder. These unloaders are used
as a way of unloading the cylinder for start-up, shutdown, or to control capacity of the
compressor during operation. Customer requirements and compressor design determine the
specific applications for the type of unloader to be used. Refer to Figure 4-33 for the features of
a typical unloader.
4-83
TP-5134
Figure 4-33. Features of a Typical Unloader

4-84
Dresser-Rand unloaders are standard Air-to-Load (Direct-Acting). That is, pneumatic

pressure is applied to the unloader to load the end of the cylinder. When pneumatic pressure to
the unloader is turned off or fails, the unloader will automatically unload that end of the cylinder.
This reduces capacity and horsepower for that cylinder. While not very common, Air-to-Unload
(Reverse-Acting) operators are available. On both types of unloaders, a protruding indicator
pin shows the unloaded condition, while a recessed indicator pin shows the loaded condition.
Refer to Figure 4-34 for details of typical D-R inlet valve unloader configurations.
TP-5064
Figure 4-34. Typical Inlet Valve Unloader Configurations

4-85
Figure 4-35. Typical Outer Head Clearance Pocket Unloader
Port Unloader:
The port unloader is installed in a suction valve hole with the suction valve removed.
The unloader valve seats against a valve blank or “donut” instead of the actual cylinder valve
port. When the unloader valve is seated, the suction passage is closed, effectively loading that
end of the compressor cylinder. When the unloader valve is unseated, the suction passage is
opened, creating a bypass and unloading that end of the cylinder. Gas admitted to the
compressor cylinder on the suction stroke passes freely back on the discharge stroke without
being compressed.
Plug Unloader:
The plug unloader is used in conjunction with a partial suction valve. The partial suction
valve has a hole through the center of the valve. When the unloader valve is seated, the center
hole is “plugged” and the suction valve functions normally. When the unloader valve is
unseated, the center hole is “unplugged” which allows the gas in the cylinder to bypass the
valve through the center opening, unloading that end of the compressor cylinder.
4-86
Clearance Pocket Unloader:
The clearance pocket unloader is used to open and close a cylinder clearance pocket.
When the unloader valve is seated, the additional volume of the clearance pocket is closed off
from the cylinder. When the unloader valve is unseated, the additional clearance volume of the
pocket is opened to the compressor cylinder, thus reducing cylinder capacity.
Packing Gland Designs:
Dresser-Rand unloaders are supplied with a

standard O-ring packing gland design with vent and
purge capability. With the standard sweeping
purge O-ring gland (Figure 4-36), any gas leakage
is directed into the plant gas disposal (flare) or
vapor recovery system through the gland vent.
Figure 4-36. Sweeping Purge Unloader Gland
An optional multi-O-ring gland with inert

buffer gas purge (Figure 4-37) may be
encountered. The multi-O-ring gland design
prevents process gas from passing the O-ring
seals during normal operation. However, if
leakage occurs, it is contained within the vent
system by an additional set of O-rings.
TP-5066
Figure 4-37. Optional Buffer Purge Unloader Gland
An alternate packing gland design may be

encountered that utilizes spring-energized Teflon®
seals (Figure 4-38). The Teflon® seals are energized
by special metal springs to maintain lip contact during
no or low pressure conditions. The Teflon® gland
consists of three seals (bottom, middle, top)
separated by two spacers (one spacer on each side
of the middle seal). The spacers are drilled through
for alignment with the vent passages in the unloader
cover.
T P -5 0 6 7
Figure 4-38. Teflon® (Flexi®seal) Packing

4-87
Dresser-Rand has available an optional Bellows

Type Seal on its plug, port and pocket unloaders. 1. Bellows Seal
The bellows seal (1) surrounds the piston rod (2) 2. Piston rod
where it protrudes beneath the unloader cover (3) 3. Unloader cover
as shown in Figure 4-39. The bellows configuration
allows the seal to expand and contract while 3
maintaining the seal, as the piston rod moves in the
process of plugging and unplugging the valve
discharge hole, preventing gas from escaping
along the piston rod.
2
When the bellows type seal is employed,
1
the packing gland around the smaller diameter of
the piston rod going through the unloader cover,
becomes a secondary, or backup seal, to prevent
any gas from escaping along the piston rod. TP-5068
Figure 4-39. Bellows Type Seal

Replacement Parts:
The design of the Dresser-Rand unloader is such that special materials and
manufacturing methods are required. To ensure correct operation of the unloader, use only
genuine Dresser-Rand parts replacement parts.
When ordering replacement parts, give the compressor frame and cylinder serial
numbers, and the size of the compressor valves, as well as the applicable parts numbers from
the unloader parts list. A convenient unloader rebuild kit is available that contains a
complete set of O-rings, backup rings and gaskets needed for servicing the unloader.
Replacement parts inventories must be carefully handled to prevent mixing similar parts
for different unloaders. The unloaders are designed for various service and pressure
conditions; many of the parts are similar in appearance but have latent differences. Accidental
use of incorrect unloader parts can result in reduced compressor performance and shortened
valve and unloader service life. It is advisable to maintain an easily recognizable and practical
spares control system for the unloaders and other compressor parts.
A. Control and Vent Piping Considerations
DO NOT plug the vent/purge connection in the unloader cover.

The vent/purge opening must always be left open to assure
safe and effective operation of the unloader. When the process
gas is toxic, flammable, narcotic, or in any other way
objectionable in the compressor building, all applicable safety
precautions must be observed. The vent/purge must be piped
to a non-hazardous area, such as a gas disposal (flare) or
vapor recovery system. Vent piping must not be less than 3/8-
inch (9.5 mm) O.D. and, if combined with other vent systems,
there must not be any back pressure or vacuum in this piping.
4-88
Typically a ¼-inch NPT operating pressure inlet connection is located in the operator
and a ¼-inch NPT vent/purge connection is located in the unloader cover. Refer to the job-
specific Capacity Control Piping and Instrumentation Diagram located in the DRAWINGS
section of the Service Manual, which shows the arrangement of the factory-supplied piping,
control logic and operating pressure requirements.
B. Unloader Cleanliness
1. The unloaders must be clean and tight to operate satisfactorily. Each unloader should
be examined during normally scheduled valve maintenance and/or compressor
maintenance inspection cycles. Experience and operating conditions will dictate the
time interval between inspection intervals.
2. Working in a well-lit and clean environment, examine the operator, indicator, unloader
guide and packing gland, for cracks, nicks, scoring, steps, leaks or other signs of
defects. Replace any worn or broken components.
3. Examine all O-rings, backup rings, seals and gaskets carefully; replace if they are cut,
scored, deformed or appears brittle. An O-ring, which shows evidence of a thin edging
on its outside diameter, has been permitted to extrude from its retaining cavity when
under pressure. This could be the result of inadequate tightening or there could be dirt,
nicks or burrs between the mating surfaces. Always use replacement O-rings identified
by the proper part number. Identical physical dimensions do not necessarily indicate the
proper replacement O-ring, since many services require specially compounded rings to
obtain specific physical characteristics, such as high oil resistance, heat resistant,
abrasion resistance, extrusion resistance, etc. Before assembling O-rings, lightly coat
the O-ring and mating surfaces with a lubricant compatible with the O-ring material and
application. Parker® Super O-Lube is a silicone lubricant that can be used with any
rubber polymer and most applications.

4. To thoroughly clean the unloader assembly, it must be completely dismantled. Soaking

the unloader parts in a safety solvent, followed by a stiff brushing or light scraping, will
aid in the removal of hardened deposits. Brush the parts carefully with a soft wire brush,
but use a bristle brush for all the seating surfaces. Blow away all of the loose particles
with compressed air. All components must be thoroughly dried before reassembly.
4-89
C. Removing the Operator, Unloader and Valve Assembly
PRESSURED EQUIPMENT. Before performing any service on

the unloader, including the removal of the upper housing cover
for inspection purposes be certain there is no pressure in the
compressor cylinder bore and piping. Failure to vent pressure
before removing the unloader could cause the unloader to be
ejected during removal resulting in severe personal injury or
death.
1. Shut down and vent ALL pressure from the compressor cylinder and piping.
2. Disconnect the vent/purge tubing from the unloader along with the operating pressure
tubing to the unloader operator.
3. Mark or tag the unloader and its related assemblies (unloader cover, cage, donut, etc.)
as they are removed. Ensure that the parts are returned to their original locations at
reassembly.
PROJECTILE HAZARD-TRAPPED PRESSURED GAS. With the

O-ring body seal used on this type valve cover, any pressure
that may be left in the cylinder will not be released when the
cover nuts are loosened, but will remain under the cover
trapped by the O-ring. To prevent the possibility of the valve
cover being "blown off" by residual pressure when the cover
nuts are removed, two longer studs are required to permit the
safe removal of the cover. These studs are either present (they
are double nutted if factory supplied) or should be fabricated at
the site. FAILURE TO OBSERVE THE FOLLOWING VALVE
REMOVAL PROCEDURE CLOSELY CAN RESULT IN POSSIBLE
PROPERTY DAMAGE, INJURY OR DEATH TO THE
OPERATING/MAINTENANCE PERSONNEL.
4. Locate the two longer cover studs. These are diametrically opposed across the
unloader cover bolt pattern. If such studs are not installed, then fabricate two studs and
install them (with 2 nuts on each stud) 180 degrees apart before loosening or removing
any other stud nuts.
5. Evenly loosen all the unloader cover stud nuts. Remove only those nuts on the shorter
unloader cover studs. At this point, the nuts on the longer unloader cover studs are the
only items securing the unloader cover.
4-90
SERVICE NOTE
If the unloader assembly is stuck in the cylinder, striking edgewise

on the unloader cage (or yoke) with a wooden block or a soft metal
bar usually can jar it free.
6. Equally loosen the nuts on the longer studs two turns at a time. As the stud nuts are
loosened, it may be necessary to tighten down the unloader cover jackscrews (if so
equipped) or to carefully pry under the unloader cover to keep the cover in contact with
the stud nuts. This will prevent sudden loosening or blowing off of the unloader cover
when the O-ring breaks free of the valve passage. As the O-ring is slowly pulled free
from the valve passage, any residual pressure will be safely vented from under the
cover while the unloader is retained to the cylinder by the longer studs and nuts. Finally,
remove the nuts from the longer studs.
7. Using an overhead hoist and sling of sufficient capacity, carefully remove the unloader
assembly along with the valve cage and suction valve (“donut”) assembly from the
cylinder. (Typically, the valve cage is fastened to the suction valve to facilitate handling
the parts as an assembly.)
8. Finally, remove the valve seat or “donut” gasket that is located under the valve. This
gasket should not be reused. Always install a new gasket and O-rings when re-
installing the unloader assembly.
SERVICE NOTE
If two or more unloaders are removed, then mark each one to be

sure it is reinstalled into the same valve passage from which it was
removed. Also, install temporary covers over all of the unloader
passage(s) to prevent debris from falling into the cylinder.
9. If required, service the suction valve as described in Paragraph 4-19 of this Instruction
Manual.
D. Disassembling the Operator – Air-to-Load (Direct-Acting)
1. Referring to Figure 4-33, remove the long external piston housing capscrews, then
remove the piston housing cover with indicator. Finally, remove and discard the housing
gasket.
2. Remove the capscrew that fastens the actuating piston to the unloader rod, then remove
the piston and piston return spring from the piston housing. Remove and discard the
piston O-ring and gasket.
3. Remove the piston (upper) housing from the operator (lower) housing
4. Remove the capscrews that fasten the operator (lower) housing to the top of the
unloader cover. Then remove the operator housing.
4-91
5. Refer to Paragraph G - "Disassembling the Unloader Guide" to access the packing

gland.
E. Disassembling the Operator – Air-to-Unload (Reverse-Acting)
PROJECTILE HAZARD – SPRING(S) IN COMPRESSION

With air-to-unload, (reverse-acting) operators (spring(s) located
above actuating piston), the piston return spring(s) exerts
considerable force against the piston housing cover. To
prevent the spring(s) from being ejected when the cover is
removed, two longer capscrews are supplied with the piston
housing. These longer capscrews allow the spring(s) to fully
decompress while maintaining thread engagement with the
housing.
1. Referring to Figure 4-34, first remove the stud nuts or capscrews with the shorter
thread engagement. Slowly and evenly remove the capscrews with the longer thread
engagement allowing the piston return spring(s) to decompress. Remove the remaining
stud nuts or capscrews and the piston housing cover.
2. Remove the spring(s) from the piston housing.
3. Grasp the indicator rod attached to the top of the actuating piston and pull the piston out
of the piston housing. Then remove and discard the piston O-ring.
4. Remove the piston housing from the unloader cover. Then remove and discard the
housing gasket.
5. Refer to Paragraph G - "Disassembling the Unloader Guide" to access the packing

gland.
F. Disassembling the Indicator (If Applicable)
SERVICE NOTE
The indicator installed in the piston housing cover is sealed with a

gasket while the indicator stem is sealed with an O-ring. Periodic
inspection and replacement of these sealing pieces is
recommended to ensure an airtight chamber.
4-92
1. Stem
2. O-ring
3. Housing
4. Spring
5. Retaining Ring
6. Gasket
TP-5135
Figure 4-40. Indicator
1. Unscrew the indicator from the piston housing upper cover.
2. Refer to Figure 4-40, remove the external retaining ring (#5) from the indicator stem
(#1).
3. Withdraw the indicator stem (#1) from indicator housing (#3). Then remove and discard
the O-ring (#2).
4. If the retaining spring (#4) did not come out with the indicator stem, it may be lodged in
the hole where the stem was withdrawn from. If required, carefully remove the spring.
5. Remove and discard the gasket (#6) from the indicator housing (#3).
G. Disassembling the Unloader Guide
1. Referring to Figure 4-33, remove the capscrews that fasten the unloader valve to the
crossbar, then pull the unloader valve off the unloader guide. (It may be necessary to
slide the unloader valve down on the guide to provide access to the capscrew heads.)
Clean and inspect the unloader valve's tapered seating surface for excessive wear or
damage. Replace the unloader valve if necessary.
2. Remove the shoulder bolt that fastens the crossbar to the bottom of the unloader rod.
Then remove the crossbar.
3. Remove the capscrews that fasten the unloader guide to the bottom of the unloader
cover. Then remove the guide.
4. Remove and discard the unloader guide seal ring(s). Clean and inspect the seal ring
groove(s) for excessive wear or damage. Replace the guide if necessary.
5. Finally, remove the unloader rod.
4-93
H. Servicing the Packing Gland
1. If applicable, remove the packing gland flange capscrews. Then remove the flange.
2. Referring to Figures 4-36 through 4-38), pull the O-ring packing gland (or Teflon® seals
and spacers) from the unloader cover counterbore.
3. Remove and discard the gland O-rings and backup rings, or Teflon® seals.
SERVICE NOTE
Refer to Paragraph B – “Unloader Cleanliness” before the

reassembly of any unloader component begins.
Figure 4-41. Gland Seal Detail
4. Install new O-rings and backup rings (if used) on the gland seal (see Figure 4-41).
Notice that the backup ring is placed above the O-ring and that the concave surface of
the backup ring faces toward the O-ring.
5. Insert the O-ring gland (or Teflon® seals and spacers as shown in Figure 4-38) into the
unloader cover counterbore. Make sure the beveled end of the O-ring gland is facing
down or, if used, make sure the Teflon® seal springs are facing down toward the
pressure.
4-94
6. If applicable, reinstall the packing gland flange. Tighten the capscrews firmly.
I. Reassembling the Unloader Guide
SERVICE NOTE

1. Referring to Figure 4-33, lubricate the unloader rod with O-ring lube. Then carefully
install the rod up through the unloader cover and packing gland or if used the Teflon®
seals and spacers.
2. Fit the unloader guide to the bottom of the unloader cover. Apply Loctite® 242
Threadlocker to the capscrew threads, then install the unloader guide capscrews and
tighten firmly.
3. Fit the crossbar to the bottom of the unloader rod. Apply Loctite® 242 Threadlocker to
the shoulder bolt, then install the shoulder bolt and tighten firmly. (Wrench flats are
usually provided on the unloader rod to hold the rod and prevent it from turning while
installing the shoulder bolt.)
4. Install a new seal ring(s) into the groove(s) on the unloader guide.
5. While carefully compressing the seal ring(s), push the unloader valve onto the unloader
guide.
6. Fit the unloader valve to the crossbar. Apply Loctite® 242 Threadlocker to the unloader
valve capscrews, then install the capscrews and tighten firmly. (It may be necessary to
slide the unloader valve down on the guide to provide access to the capscrew heads.)
J. Reassembling the Indicator (If applicable)
SERVICE NOTE

1. Referring to Figure 4-40, lubricate a new indicator O-ring (#2) and place in the groove of
the indicator stem (#1).
2. Place the spring (#4) over the stem (#1) and insert the stem and spring together into the
hole in housing (#3).
3. Place the retaining ring (#5) in the groove at the end of the stem to keep the stem in
place in the indicator.
4-95
4. Assemble using a new gasket (#6) and attach the indicator as shown in Figure 4-33 to
the operator housing cover before attaching the cover to the operator.
K. Reassembling the Operator – Air-to-Load (Direct-Acting)
SERVICE NOTE

reassembly of any unloader component begins. Also, make sure
the indicator is installed (see Paragraph J) before continuing the
assembly process of the operator, if required.
1. Referring to Figure 4-33, place the operator (lower) housing onto the unloader cover.
Apply Loctite® 242 Threadlocker to the housing capscrews. Then install the capscrews
and tighten firmly.
2. Place the piston return spring into the operator (lower) housing. Then place the piston
(upper) housing on top of the operator (lower) housing.
3. Install a new gasket between the actuating piston and unloader rod. Install a new piston
O-ring, then apply O-ring lubricant. Fit the piston to the unloader rod. Apply Loctite®
242 Threadlocker to the piston capscrew and install the capscrew to compress the
piston spring and draw the piston down into the piston housing.
4. Install a new piston (upper) housing gasket. Then place the piston housing cover with
indicator onto the piston housing. Install the long piston housing capscrews and tighten
firmly.
L. Reassembling the Operator – Air-to-Unload (Reverse-Acting)
SERVICE NOTE

1. Referring to Figure 4-34, install a new piston O-ring, then apply O-ring lubricant. Place
the actuating piston with the indicator rod pointing up on top of the unloader rod.
2. Install a new piston housing gasket into the groove on top of the unloader cover. Then
carefully place the piston housing over the piston and down onto the unloader cover.
Make sure the inlet connection is down and properly aligned so that it will reconnect to
the installed tubing.
3. Place the piston spring(s) on top of the piston.
4. Place the piston housing cover on top of the piston spring(s). Then reinstall the two
piston housing capscrews with the longer thread engagement. Tighten the capscrews
gradually and evenly to compress the spring(s) and draw the cover down. Finally,
4-96
reinstall the remaining stud nuts or capscrews with the shorter thread engagement.
M. Installing the Operator – Air-to-Load (Direct-Acting)
1. Remove the temporary covers that were placed over the unloader passage(s).
2. Install a new suction valve (or donut) gasket as applicable. If applicable, install new
valve/unloader cover O-ring(s). Place the suction valve (or donut) and cage into the
valve hole. (Typically, the suction valve is fastened to the cage to facilitate handling
these components as an assembly.)
3. Using an overhead hoist and sling of sufficient capacity, install the unloader into the
cylinder valve hole; valve cage or clearance pocket as applicable. Make sure the
unloader guide tabs engage the "donut", partial valve or clearance pocket port.
4. Reconnect the operating pressure inlet, vent and purge (if used) piping.
5. Rundown the unloader cover nuts until they contact the cover, and then back them off
approximately one full turn.
6. Apply operating pressure to the unloader operator to seat the unloader valve. This will
align the unloader valve with its seating surface; i.e., the "donut", partial valve or
clearance pocket port.
7. Release and then reapply operating pressure to the unloader operator.
Tightening of the unloader cover stud nuts is critical. Under

loosening of the unloader cover during operation with the
pre-stress required. Then move down the column to the
correct fastener size to obtain the proper torque value. This
torque value only applies when the specified thread lubricant is
used.
8. With the operating pressure applied, tighten the unloader cover stud nuts to the torque
value specified in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-
3.6 in this Instruction Manual. Make several passes, working back and forth across the
stud circle, to ensure the unloader cover is drawn down tightly and evenly.
4-97
9. Release the operating pressure to the unloader operator, and re-torque the unloader
cover nuts one more time to the proper torque value.
N. Installing the Operator – Air-to-Unload (Reverse-Acting)
1. Remove the temporary covers that were placed over the unloader passage(s).
2. Install a new suction valve (or donut) gasket as applicable. If applicable, install new
valve/unloader cover O-ring(s). Place the suction valve (or donut) and cage into the
valve hole. (Typically, the suction valve is fastened to the cage to facilitate handling
these components as an assembly.)
3. Using an overhead hoist and sling of sufficient capacity, install the unloader into the
cylinder valve hole; valve cage or clearance pocket as applicable. Make sure the
unloader guide tabs engage the "donut", partial valve or clearance pocket port.
4. Reconnect the operating pressure inlet, vent and purge (if used) piping.
5. Apply operating pressure to the unloader operator to retract the unloader valve.
Rundown the unloader cover nuts until they contact the cover, and then back them off
approximately one full turn
6. Release the operating pressure to seat the unloader valve. This will align the unloader
valve with its seating surface; i.e. the “donut”, partial valve or clearance pocket port.
7. Apply, and then release, operating pressure to the unloader operator.
Tightening of the unloader cover stud nuts is critical. Under

loosening of the unloader cover during operation with the
pre-stress required. Then move down the column to the
correct fastener size to obtain the proper torque value. This
torque value only applies when the specified thread lubricant is
used.
8. With the operating pressure released, tighten the unloader cover stud nuts to the torque
value specified in CHAPTER 5, GENERAL DATA AND SPECIFICATIONS Paragraph 5-
3.6 in this Instruction Manual. Make several passes, working back and forth across the
stud circle, to ensure the unloader cover is drawn down tightly and evenly.
4-98
9. Apply the operating pressure to the unloader operator, and re-torque the unloader cover
nuts one more time to the proper torque value.
4-20.2. Variable Volume Clearance Pockets
The Variable Volume Clearance Pocket (VVCP) is installed in the outer head of the
compressor cylinder. For cylinder bores 13.00 inch and smaller, the outer head is a one-piece
style (See Figure 4-42). For cylinder bores larger that 13.00 inch, the outer head is a two-piece
style (See Figure 4-43). For plug style (See Figure 4-44). The VVCP can be adjusted while the
compressor is running OR when the compressor is shut down and the cylinder depressurized.
DO NOT plug the vent connection in the VVCP housing. The

vent opening must always be left open to assure safe and
effective operation of the lantern ring seals. When the
process gas is toxic, flammable, narcotic, or in any other
way objectionable in the compressor building, all applicable
safety precautions must be observed. The vent must be
piped to a non-hazardous area, such as a gas disposal
(flare) or vapor recovery system. Vent piping must not be
less than 3/8-inch (9.5 mm) O.D. and, if combined with other
vent systems, there must not be any back pressure or
vacuum in this piping.
The VVCP is equipped with seals that are installed on each side of a lantern ring. This
seal assembly is held in place by a flat washer and secured by a retaining ring (See Detail A in
Figures 4-42, 4-43 and 4-44). There is also a vent port in the main body housing that is located
over the lantern ring that allows a test gauge or a vent to be connected.
The volume is changed by means of a movable piston. The piston is attached to the
piston rod by a threaded connection between the piston and the rod. Loosening the Locking
Wrench and turning the Actuating Wrench handle in the clockwise direction, which will draw the
piston outward away from the cylinder, increases the clearance volume. Within the limits of the
pocket capacity (See Table 4-5), the exact amount of clearance volume can be added by
turning the Actuating Wrench. Close control over the required cylinder capacity can be
accomplished by setting the piston at some intermediate position between fully closed and fully
open.
A grease fitting in the main body housing allows the piston rod threads to be greased.
Periodic maintenance consists of applying a small amount of grease, compatible with the
process gas, to this grease fitting. It is suggested that the grease fitting be greased before each
adjustment. If adjustment is infrequent, then the grease fitting should be greased at least one a
month.
To operate the VVCP, first use an NON-SPARKING HAMMER to loosen the Locking
Wrench in the counter-clockwise direction. Move the plunger pin handle to the locked (slotted)
position and continue to turn the Locking Wrench counter-clockwise until the plunger pin
engages the Actuating Wrench. Once the Locking Wrench is loose and engaged with the
Actuating Wrench, the Adjusting Wrench handle can be turned by hand clockwise to open the
pocket, or counter-clockwise to close the pocket. The position of the pocket is conveyed by the
Position Indicator, which can be seen through the sight glass (See Figure 4-45). Once the
4-99
pocket is in the desired position, the plunger pin needs to be pulled out of the slot and rotated to
the unlocked position. Then, just the Locking Wrench can be hand tightened in the clockwise
direction. To finish locking, use the non-sparking hammer to fully tighten the Locking Wrench.
Figure 4-42. Variable Volume Clearance Pocket (One-Piece Head)
4-100
Figure 4-43. Variable Volume Clearance Pocket (Two-Piece Head)

4-101
Figure 4-44. Variable Volume Clearance Pocket (Plug Type)
TP-5138
Figure 4-45. VVCP Position Indicator

4-102
Table 4-5. Maximum Allowable Clearance Volume
Nominal Cylinder Maximum Stroke Maximum Total

Size of VVCP Piston VVCP Volume
3
Inch Inch Inch
4.75 5.00 79.5
5.75 5.00 84.0
6.00 5.00 93.3
6.50 5.00 98.2
7.00 5.00 108.2
7.75 5.00 141.4
8.00 5.00 153.4
9.00 5.00 192.4
9.50 5.00 220.9
10.50 5.00 267.3
11.50 5.00 318.1
12.25 5.00 354.4
13.00 5.00 392.7
14.00 5.00 464.4
15.00 5.00 542.2
16.25 5.00 663.7
17.50 5.00 825.7
19.00 5.00 883.6
20.50 5.00 1037.0
22.00 5.00 1151.7
23.00 5.00 1254.7
24.50 5.00 1610.3
26.00 5.00 797.4
26.50 5.00 797.4
A. Removal/Disassembly of the One-Piece Style Outer Head

outer head. It is particularly important that ALL PRESSURE is
the VVCP. CAREFULLY CRACKING OPEN drain valves on inlet
and discharge manifolds is a good method to determine if any
pressure exists in the cylinder bore, cylinder passages and
PRECAUTIONS ARE NOT STRICTLY OBSERVED.
4-103
Figure 4-46. VVCP Assembly – (One-Piece Head)
1. Referring to Figure 4-46, use an NON-SPARKING HAMMER to first loosen the Locking
Wrench (#15). Then loosen, but do not remove, the eight (twelve on some units) long
bolts (#29) that secure the Cover (#12) to the VVCP. Also loosen but do not remove the
stud nuts (#4) that secure the VVCP Outer Head (#1) to the cylinder.
2. Using a hoist arrangement capable of taking the weight along with a sling, fully support
the VVCP assembly and then remove the stud nuts (#4). Carefully pull the clearance
pocket head assembly straight out of the cylinder keeping it level until the Outer Head
(#1) clears the bore.
3. While suspended, remove the piston retaining ring (#30) by first prying one end out of
the groove, then by winding the ring completely out. Carefully set the assembly down
on the Outer Head (#1) so the VVCP is standing upright.
4. Remove the Locking Wrench (#15), Actuating Wrench (#14), the 8 (or 12) long cover
bolts (#29) and the Cover (#12). With these removed, the Actuating Wrench can then
be placed back over the Retaining Nut (#11) and key (#13) and used to remove the
Retaining Nut off the VVCP Rod (#20).
5. Remove the sight glass (#23) and unthread the Position Indicator screw (#22) from the
VVCP Rod.
6. Slowly and carefully lift the main body Housing (#10) over the VVCP Rod and off of the
Outer Head.
4-104
7. Remove the seal retaining ring (#6) and washer (#7). Then pull the two seals (#8),
Lantern Ring (#9) and remaining washer (#7) from the main body Housing bore.
8. Remove scraper ring (#34), if any. Examine the bushing (#33). Unless seriously
damaged, it should not need to be removed.
9. Slowly and carefully lift the Outer Head off the VVCP Piston and Rod assembly.
Remove the Piston Ring (#21) from the VVCP Piston (#20). Leave the Piston attached
to the VVCP Rod.
10. Finally, remove and discard the Outer Head Gasket (#2) and two O-rings (#5) from the
main body Housing.
B. Assembly/Installation of the One-Piece Style Outer Head

1. Prior to assembly and referring to Figure 4-46, thoroughly degrease with solvent and dry
the VVCP Rod (#20), main body Housing (#10), Retaining Nut (#11) and Locking
Wrench (#15). Check the threads of these components for any damage and replace
them if necessary.
2. Install a washer (#7), the Lantern Ring (#9) and two new Seals (#8) with the open cup
side of the seals facing the pressure (towards the cylinder bore) into the main body
Housing. Then install the remaining Washer (#7) and Retaining Ring (#6), making sure
the retaining ring is tight in its groove. Install the Scraper Ring (#34), if any, from the
frame end of the Outer Head.
3. Install a new Piston Ring (#21) onto the VVCP Piston (#20). Carefully lower the Outer
Head (#1) slowly and carefully back down over the Piston. Install two new O-rings (#5)
and place the main body Housing back on the outer head with the sight glass opening
oriented toward the top of the head.
4. Thread the Retaining Nut (#11) back onto the VVCP Rod. Place the Cover (#12) over
the nut and secure with the 8 (or 12) long Cover Bolts (#29). Put the Key (#13),
Actuating Wrench (#14) and the Locking Wrench (#15) onto the Piston.
5. Locate the indicator thread hole on the VVCP Rod and thread in the Position Indicator
screw (#22) using a small amount (two drops) of Loctite® 242 Threadlocker or
equivalent. Install the sight glass (#23).
6. Using a hoist arrangement capable of taking the weight along with a sling, lift and rotate
the VVCP assembly into a horizontal position. While suspended, install the piston-
Retaining Ring (#30) making sure it is tight in its groove.
4-105
7. Install a new Outer Head Gasket (#2) and carefully slide the VVCP assembly straight
into the cylinder bore making sure that the Outer Head is positioned correctly.
8. Install the stud nuts (#4). Torque up all of the stud nuts, and the long cover bolts (#29),
in a criss-cross fashion, in several stages, to the torque value specified in CHAPTER 5,
GENERAL DATA AND SPECIFICATIONS Paragraph 5.3 in this Instruction Manual, Bolt
Type. Exception: the long Cover Bolts (#29) are to be tightened to the 40,000-psi pre-
stress value.
9. Using the grease fitting (#27) on the main body Housing, apply grease compatible with
the process gas.
10. Make sure to adjust the VVCP Piston to the desired location and then tighten the
Locking Wrench (#15) securely with an NON-SPARKING HAMMER.
C. Removal/Disassembly of the Two-Piece Style Outer Head
Figure 4-47. VVCP Assembly – (Two-Piece Head)
4-106

Wrench (#15). Then loosen, but do not remove, the eight long Bolts (#29) that secure
the Cover (#12) to the VVCP. Also loosen but do not remove the stud nuts (#4) that
secure the VVCP Outer Head (#1) to the cylinder.
2. Using a hoist arrangement capable of taking the weight along with a sling, fully support
the VVCP assembly and then remove the stud nuts (#4). Carefully pull the clearance
pocket head assembly straight out of the cylinder keeping it level until the Outer Head
(#1) clears the bore.
3. Carefully set down the assembly on the Outer Head (#1) so that the VVCP is standing
upright. Loosen but do not remove the four Allen-head capscrews (#32) that secure the
Outer Head Cover (#30) to the Outer Head (#1)
4. Remove the Locking Wrench (#15), Actuating Wrench (#14), the 8 (or 12) long cover
bolts (#29) and the Cover (#12). With these removed, the Adjusting Wrench can be
placed back over the Retaining Nut (#11) and Key (#13) and then used to remove the
Retaining Nut off the VVCP rod (#20).
5. Remove the sight glass (#23) and unthread the Position Indicator screw (#22) from the
VVCP Rod.
6. Slowly and carefully lift the main body Housing (#10) over the VVCP Rod and off of the
Outer Head Cover (#30).
7. Remove the seal retaining ring (#6) and washer (#7). Then pull the two seals (#8),
Lantern Ring (#9) and remaining washer (#7) from the main body Housing bore.
8. Remove scraper ring (#35), if any. Examine the Bushing (#33). Unless seriously
damaged, it should not need to be removed.
9. Remove the four Allen-head capscrews (#32) from the outer head cover. Then slowly
and carefully lift the Outer Head Cover off the VVCP Piston and Rod assembly.
10. Slowly and carefully lift the VVCP Piston and Rod assembly (#20) out of the Outer
Head. Remove the piston ring (#21) from the VVCP Piston (#20). Leave the Piston
attached to the VVCP Rod.
11. Finally, remove and discard the Outer Head gasket (#2) and three O-rings (#5 and #31)
from the main body Housing and Outer Head, respectively.
4-107
D. Assembly/Installation of the Two-Piece Style Outer Head

1. Prior to assembly and referring to Figure 4-47, thoroughly degrease with solvent and dry
the VVCP Rod (#20), main body Housing (#10), Retaining Nut (#11) and Locking
Wrench (#15). Check the threads of these components for any damage and replace
them if necessary.
2. Install a washer (#7), the Lantern Ring (#9) and two new seals (#8) with the open cup
side of the seals facing the pressure (towards the cylinder bore) into the main body
Housing. Then install the remaining washer (#7) and retaining ring (#6), making sure the
retaining ring is tight in its groove. Install scraper ring (#35), if any.
3. Install a new piston ring (#21) onto the VVCP Piston (#20), along with a new O-ring
(#31) into the Outer Head (#1). Carefully lower the VVCP Piston and Rod assembly
slowly back down into the Outer Head. Place the Outer Head Cover (#30) onto the
Outer Head and secure with the four Allen-head capscrews (#32).
4. Install two new O-rings (#5) and place the main body Housing back on the Outer Head
Cover with the sight glass opening oriented toward the top of the head.
5. Thread the Retaining Nut (#11) back onto the VVCP Rod. Place the Cover (#12) over
the nut and secure with the 8 (or 12) long cover bolts (#29). Put the Key (#13),
Actuating Wrench (#14) and Locking Wrench (#15) onto the VVCP Rod.
6. Locate the indicator thread hole on the VVCP Rod and thread in the Position Indicator
screw (#22) using small amount (two drops) of Loctite® 242 Threadlocker or equivalent.
Install the sight glass (#23).
7. Using a hoist arrangement capable of taking the weight along with a sling, lift and rotate
the VVCP assembly into a horizontal position. Install new Outer Head gasket (#2) and
carefully slide the VVCP assembly straight into the cylinder bore making sure that the
outer head is positioned correctly.
8. Install the stud nuts (#4). Torque up all of the stud nuts, and the long cover bolts (#29),
in a criss-cross fashion, in several stages, to the torque value specified in CHAPTER 5,
GENERAL DATA AND SPECIFICATIONS Paragraph 5.3 in this Instruction Manual. Bolt
Type Exception: the long cover bolts (#29) are to be tightened to the 40,000-psi pre-
tress value.
9. Using the grease fitting (#27) on the main body Housing, apply grease compatible with
the process gas.
10. Make sure to adjust the VVCP Piston to the desired location and then tighten the
Locking Wrench (#15) securely with a NON-SPARKING HAMMER.
4-108
E. Removal /Disassembly The Plug Type VVCP, Use The Following Steps;
Figure 4-48 Plug Type VVCP Assembly
WARNING
Wrench (#15). Then loosen and remove the 8 or 12 stud nuts (#4) that secure the
VVCP assembly to the cylinder.
2. Pull the clearance pocket plug assembly from the cylinder, keeping the unit level until
the Outer Plug Head (#1) clears the bore. Be sure the assembly is fully supported at all
times with a sling and hoist arrangement capable of taking the weight.
4-109
3. Set down the assembly so that the VVCP is standing upright with the Outer Head face
on the ground.
4. Remove the three cap screws attaching the Housing to the Outer Head. Remove two
cap screws (#29) from the Cover (#12).
5. Remove the Locking Wrench (#15), Actuating Wrench (#14) and the Cover (#12). With
these removed, the Actuating Wrench (#14) can be placed back over the Retaining Nut
(#11) and Key (#13) and then used to unthread the Retaining Nut (#11) off the VVCP
Rod (#20). Remove sight glass (#23) and unthread the Position Indicator screw (#22)
from the VVCP Rod (#20).
6. Slowly and carefully lift the main body Housing (#10) off the Outer Plug Head (#1), flip
180 degrees and set on the ground.
7. Remove the seal Retaining Ring (#6) and Washer (#7)and then pull out the two Seals
(#8) and Lantern Ring (#9) and remaining washer.
8. Carefully remove VVCP Rod (#20) from Outer Plug Head (#1). Piston will stay attached.
Remove the Piston Ring (#21) from the Piston.
9. Remove and discard Outer Head Gasket (#2) and two O-rings (#5) from the Housing.
F. Installation /Assembly the Plug Type VVCP, use the following steps;
1. Prior to assembly, thoroughly degrease with solvent and dry VVCP Rod, Housing
Retaining Nut and Locking Wrench.
2. Install Washer (#1), Lantern Ring (#9) and new Seals (#8) with the open side of the
seals facing pressure. Install the remaining Washer (#7) and Retaining Ring (#6),
making sure the ring is tight in its grove.
3. Install new Piston Ring (#21). Then install new O-rings (#5) to Housing.
4. Place Outer Plug Head with frame end face on the ground. Carefully lower VVCP and
Rod Assembly back down into the Outer Plug Head (#1). Carefully place the Main Body
Housing down over the VVCP Rod and onto the Head.
5. Thread the Retaining Nut (#11) back on to the VVCP Rod (#20), place the Cover (#12)
over the nut and secure it with the two Cap Screws (#29). Put the Key (#13), Adjusting
Wrench (#14) and Locking Wrench (#15) on the VVCP Rod (#20).
6. Locate the indicator thread hole on the VVCP Rod (#20) and thread in position indicator
screw (#22) using small amount (two drops) of Loctite ® 242 thread locker or
equivalent. Install the Sight Glass Gasket (#30) and Sight Glass (#23).
7. Sling and lift the VVCP. Install new Outer Head Gasket (#2).
4-110
8. Slide into position and install over the long tie rod/studs from the cylinder. Torque up all
stud nuts in a criss-cross fashion, in several stages, to 40,000 psi pre-stress.
9. Using the grease fitting on the Housing, apply grease compatible with the process gas.
10. Adjust the VVCP Piston to the desired location and tighten the Locking Wrench securely
with a NON-SPARKING HAMMER.
4-111
Form PG-4875-C
DRESSER-RAND GENERAL DATA AND SPECIFICATIONS
HOSS
CHAPTER 5
Paragraph Page
5-1. GENERAL AND OPERATING DATA ................................................................ 5-2

Table 5-1. HOSS Compressor General Data ................................. 5-2
5-2. ASSEMBLY FITS AND CLEARANCES ............................................................ 5-4
Table 5-2. Running Gear Fits and Tolerances (Inches) ................. 5-4
Table 5-2A. Running Gear Fits and Tolerances (Metric) ................ 5-5
5-3. TIGHTENING REQUIREMENTS ...................................................................... 5-6
5-3.1. Preparation of Thread and Seating Surfaces .............................................. 5-6
5-3.2 Recommended Tightening Sequence / Procedure ..................................... 5-6
5-3.3. Closely Observe the Following .................................................................... 5-6
5-3.4. Checking Fastener Tightness...................................................................... 5-7
A. When to Check Fastener Tightness .................................................. 5-7
B. How to Check Fastener Tightness .................................................... 5-8
5-3.5. Fastener Pre-Stress .................................................................................... 5-8
5-3.6. Compressor Cylinder Bolting ....................................................................... 5-9
Table 5-3. Pre-Stress Levels for HOSS.......................................... 5-9
5-3.7. Standard Torque Values ............................................................................. 5-10
Table 5-4. Torque Values Based on Common Mineral Oil ............. 5-10
5-3.8. Frame and Running Gear Bolting ................................................................ 5-11
Table 5-5. HOSS Torque Wrench Values ...................................... 5-11
5-1
General Data and Specifications PG-4875-C (HOSS)
5-1. GENERAL AND OPERATING DATA
The specifications supplied in this section apply to both the standard 6-inch and 7-inch
stroke HOSS compressor, rated at 75,000 pounds (34 000 kg) rod load. Contact the nearest
Dresser-Rand branch office if there is any question about a specification or recommendation in
Table 5-1. HOSS Compressor General Data
Number of Throws 2 4 6
Number of Main Bearings 2 4 6
Oil Sump Capacity (GAL) 34 69 105

(L) 129 261 397
Main Oil Pump (GPM) 63 94 125

Output @ 1000RPM (LPM) 238 356 473
Main Oil Pump (GPM) 76 113 150

Output @ 1200RPM (LPM) 288 428 568
Maximum Operating Speed

7.00-Inch Stroke (RPM) 1000 1000 1000
6.00-Inch Stroke (RPM) 1200 1200 1200
Minimum Operating Speed

500 500 500
7.00-Inch Stroke (RPM)
6.00-Inch Stroke (RPM) 500 500 500
Frame:
Nominal Operating Temperature ..........................................................................160F (71C)
Lubricating Oil:
Normal Oil Pressure (at Header) ..................................................... 50-65 PSIG (344-448 kPa)
Minimum Oil Pressure (at Header) .............................................................. 40 PSIG (275 kPa)
Shutdown Oil Pressure (at Header) ............................................................. 35 PSIG (240 kPa)
Minimum Start-up Oil Temperature (Electric Drive) ................................................ 80F (27C)
Minimum Load Oil Temperature (Engine and Electric Drives) ................................ 90F (32C)
Normal Oil Operating Temperature .................................................. 150 to 170F (66 to 77C)
**NOTE: Not to exceed 180F (82C) for continuous operation
For units containing main bearing RTD’s:
Maximum Alarm Setting ........................................................................................210F (99C)

Maximum Shutdown Setting .................................................................................220F (105C)
Main Bearing ∆T (Bearing to Bearing) ......................................................... Not to Exceed 20F
(Compressor fully heat soaked)
NOTE: It is recommended that the main bearing RTD alarm and shutdown be set at 20°F &
30°F respectively above the average of all the main bearing temperatures.
5-2
PG-4875-C (HOSS) General Data and Specifications
Recommended minimum prelube capacity @ 35 psi (241 kPa) (on electric motor driven
machines only):
Frame Size Gallons per Minute (Liters per

Minute)
2 Throw ..................................................................................................... 32 GPM (119 LPM)
4 Throw ..................................................................................................... 47 GPM (178 LPM)
6 Throw ..................................................................................................... 63 GPM (237 LPM)
Water-Cooled Cylinders:
Minimum Coolant Temperature (Outlet) ............................................................... 110F (43C)

Minimum Coolant Temperature (Inlet) ................................................................. 100F (38C)
Water-Cooled Packing [GPM (LPM)] per packing......................................................... 2.5 (9.5)
Nominal Pressure.........................................................................................35 PSIG (241 kPa)
Maximum Pressure ......................................................................................75 PSIG (517 kPa)
Distance Pieces:
Maximum Internal Pressure .........................................................................25 PSIG (172 kPa)
5-3
5-2. ASSEMBLY FITS AND CLEARANCES
Table 5-2. Running Gear Fits and Tolerances

(ALL DIMENSIONS ARE GIVEN IN INCHES)
Location of Original Clearance Original Clearance

Clearance or Fit Micrometer Feeler
Main Bearing Clearance (Vertical-

measured between top of crankshaft 0.006 to 0.012 0.005 to 0.011
and main bearing shell)
(Shimless Steel-Backed Bronze)
Crankshaft Total Thrust Clearance ---- 0.014 to 0.027
Connecting Rod Bearing to
Crankpin (Diametrical Clearance) 0.006 to 0.012 0.005 to 0.011
Main Bearing Cap in Frame
(Total Interference) (0.001 to 0.003) ----
Crosshead Pin in Crosshead
(Diametrical Clearance) 0.001 to 0.003 ----
Total Side Clearance between
Connrod Bushing and Crosshead ---- 0.017 to 0.029
Crosshead Pin to Connecting Rod
Bushing (Diametrical Clearance) 0.006 to 0.011 0.005 to 0.010
Crosshead Pin Bushing to Connecting
Rod (Interference) (0.003 to 0.006) ----
Crosshead Shoe to Guide (Cold) 0.014 to 0.019 0.013 to 0.018
(Hot) ------- 0.007 Minimum
Main Bearing Tie Rod Spacer to
Frame (Interference) (0.006 to 0.008) ----
[Spacer Length Less Opening
Stamped on Frame]
5-4
Table 5-2A. Running Gear Fits and Tolerances

(ALL DIMENSIONS ARE GIVEN IN MILLIMETERS)
Location of Original Clearance Original Clearance

Clearance or Fit Micrometer Feeler
Main Bearing Clearance (Vertical-

measured between top of crankshaft 0.15 to 0.30 0.13 to 0.28
and main bearing shell)
Crankshaft Total Thrust Clearance ---- 0.36 to 0.69
Connecting Rod Bearing to Crankpin
(Diametrical Clearance) 0.15 to 0.30 0.13 to 0.28
Main Bearing Cap in Frame
(Total Interference) (0.03 to 0.08) ----
Crosshead Pin in Crosshead
(Diametrical Clearance) 0.03 to 0.08 ----
Total Side Clearance between
Connrod Bushing and Crosshead ---- 0.43 to 0.74
Crosshead Pin to Connecting Rod
Bushing (Diametrical Clearance) 0.15 to 0.28 0.13 to 0.25
Crosshead Pin Bushing to Connecting
Rod (Interference) (0.08 to 0.15) ----
Crosshead Shoe to Guide (Cold) 0.36 to 0.48 0.33 to 0.46
(Hot) 0.18 Minimum
Main Bearing Tie Rod Spacer to
Frame (Interference) (0.15 to 0.20) ----
[Spacer Length Less Opening
Stamped on Frame]
5-5
5-3. TIGHTENING REQUIREMENTS
5-3.1. Preparation of Thread and Seating Surfaces
The preparation of thread and seating surfaces are equally important. In most torque
applications, more than 80% of the applied torque is used to overcome friction and the balance
is to actually stress the fastener. It is therefore imperative that the threads are clean and be
free of nicks and burrs; that the seating surfaces on the nut or bolt head and the mating surface
be smooth, flat and parallel; and that the threads and contact surfaces be properly lubricated.
The torque values provided are based on the usage of clean petroleum type oils as the
lubricant. Unless specifically specified, using Molybdenum disulfide lubricants or Anti-Seize are
not recommended due to the higher lubricity of these lubricants and the resultant over stressing
of the bolt or stud.
5-3.2. Recommended Tightening Sequence / Procedure
All fasteners used on multi-fastener joints require a tightening procedure that will allow
the fasteners to be evenly and sequentially tightened, in gradual increments, to the specified
torque. This prevents distortion of mating surfaces and "cocking" of flanged connections.
Tighten each bolt until snug using a criss-cross pattern. Next, tighten each bolt to 25
percent of the full torque value, again using a criss-cross pattern. Repeat for 50, 75 and finally
100 percent of the full torque value. Always apply a steady slow pulling force on the torque
wrench until the click is felt. Never jerk the torque wrench, as this will produce a higher torque
than desired.
5-3.3. Closely Observe the Following
1. All torque values are for clean, well-lubricated threads that are free of nicks and burrs.
For stud (or bolt) and nut combinations, the nut should turn freely on the stud threads.
Capscrews should run in freely at least up to the final assembled depth. (Some thread
interference is normal on certain self-locking fasteners.) Lubricant should be evenly
applied to both the internal and external threads, and well as the seating surfaces.
2. Wrench torques can produce fastener pre-stress variations of ±35%, depending on the
degree of lubrication or non-lubrication, and also on the condition of the seating
surfaces. A properly calibrated torque wrench is essential in obtaining satisfactory
tightening results. Under no circumstances is an impact wrench to be used for the
tightening of any fastener.
3. Geared head wrenches (torque multipliers) will not produce the full mechanical
advantage from the reduction gears. There are mechanical and friction losses of about
10% in the tool head. The tool manufacturer's instructions should be observed to
determine the exact reduction percentage for a particular torque multiplier. The required
input torque must then be increased by that percentage.
4. The torque values listed in the Standard Torque Table should be used only on those
fasteners for which a specific torque is not given.
5-6
5-3.4. Checking Fastener Tightness
The fasteners used in engines and compressors must be

correctly tightened to the design pre-stress to ensure safe
operation. After startup, fasteners that were properly tightened
can loosen due to operating temperatures and pressures,
gasket crush, fastener and joint relaxation. THEREFORE, IT IS
IMPORTANT THAT FASTENERS BE CHECKED FOR
TIGHTNESS TO ENSURE FULL MECHANICAL INTEGRITY.
Particular attention should be given to all bolts, studs and nuts
on the compressor cylinders and distance pieces and to the
cylinder-to-frame bolting.
Never check fastener tightness or tighten fasteners with the

compressor in operation or pressurized. Potential equipment
damage and/or release of process gas could result, causing
severe personal injury or death. Always check and/or tighten
fasteners when the compressor is shut down and
depressurized.
A. When to Check Fastener Tightness
Maintaining fastener tightness is very critical to fastener reliability. Dresser-Rand

recommends the following schedule for checking the tightness of all fasteners:
 Before start up, check fasteners at all the joints that have gaskets and any joints not
assembled at the Dresser-Rand factory. (Consult the job-specific instruction manual
parts list section to locate the joints containing gaskets).
 One week after startup for joints with gaskets and the entire cylinder frame bolting.
Take note of any fasteners that have loosened and pay close attention to these
fasteners. Increase the periodic checking of these fasteners.
 Anytime a joint containing a gasket has been opened, replace the gasket and tighten
the fasteners as prescribed. Then check the joint once again one week after re-start.
 Periodically based on experience, but annually is considered a typical interval.
 Anytime there is an incident, a slugging event (liquid ingestion) or excessive vibration,

which has caused a compressor overload to occur.
5-7
B. How to Check Fastener Tightness
To check the tightness of a torqued fastener, first mark the position of the bolt head or
nut to the member and then loosen it; clean it and re-lubricate with the proper lubricant. Then
tighten the fastener to the required torque value. Observe to see whether the bolt head or nut
returns back to its reference position. If it does, then the fastener was assembled correctly. If it
advances past the reference, then the fastener was loose, or it was not originally torqued
correctly. Inspect the fastener for fatigue or stress cracks and replace as required. Contact
Dresser-Rand for technical advice.
5-3.5. Fastener Pre-Stress
Fastener pre-stress (initial tightening) is calculated to prevent separation of the

connected members when they are subjected to operating forces and, in cases of cyclic
loading, to protect the fastener from the fatigue effects of the alternating tensile and
compressive stresses. Wrench torque is the most widely used method of applying fastener pre-
stress. A properly calibrated torque wrench is essential in obtaining satisfactory results. An
accurate torque cannot be applied to fasteners using a commercial impact wrench. Under no
circumstances is an impact wrench to be used for the final tightening of any fastener.
NOTE
Refer to the job-specific Instruction Manual for the specific bolting

torque values before applying these general guidelines.
In general, unless otherwise specified, the pre-stress level for a particular bolting
application can be determined as follows:
 For connections with metal-to-metal contact, use 30,000 PSI (207 MPa) stress level.
 For connections with non-metallic gaskets, use 20,000 PSI (138 MPa) stress level.
 For foundation bolts of the J type or bent bar use 25 000 PSI (172 MPa) stress level.
Note this type of anchor bolt should NEVER be used for locations that have to withstand
the dynamic loads from the compressor frame or cylinders.
 For foundation bolts which use plate type anchors (recommended for compressor frame
and cylinder anchor bolt locations) tighten to 30,000-psi (207 MPa) stress level.
5-8
5-3.6. Compressor Cylinder Bolting
In many cases, the specific torque values are given in the job-specific Instruction Manual
for each fastener required for the compressor cylinder bolting. If the specific torque value is not
given, then use the information in the following tables. Determine the application and fastener
pre-stress level, and then apply the torque value listed in the Standard Torque Table.
Table 5-3. Pre-Stress Levels for HOSS
Joint Location Fastener Pre-Stress
Cylinder To Head 30,000 psi (207 MPa)
Cylinder To Valve Cover 30,000 psi (207 MPa)
Cylinder To Packing 40,000 psi (276 MPa)
Inlet & Discharge Flange 30,000 psi (207 Mpa)
Cylinder Tie Rod 40,000 psi (276 MPa)
Clearance Device To Outer Head 30,000 psi (207 MPa)
Adjust-On-The-Fly VVCP to Outer Head/Cylinder 40,000 psi (276 MPa)
5-9
5-3.7. Standard Torque Values
Table 5-4. Torque Values Based on Common Mineral Oil

20,000 PSI 25,000 PSI 30,000 PSI 40,000 PSI
(138 Mpa) (172 Mpa) (207 Mpa) (276 Mpa)
Bolt Pre-Stress Bolt Pre-Stress Bolt Pre-Stress Bolt Pre-Stress
NOMINAL
BOLT SIZE Torque Torque Torque Torque
(inches)
Ft-lbs. Nm Ft-lbs. Nm Ft-lbs. Nm Ft-lbs. Nm
1/4 3 4 3 4 4 6 5 7
5/16 5 7 7 10 8 11 11 15
3/8 9 12 12 16 14 19 19 26
7/16 15 20 18 24 22 30 29 39
1/2 22 30 28 38 33 45 44 60
9/16 31 42 39 53 47 64 63 85
5/8 44 60 55 75 66 90 88 119
3/4 76 103 95 129 114 155 152 206
7/8 120 163 150 203 180 244 240 325
1 175 237 220 300 265 360 350 475
1-1/8 260 355 330 450 390 530 520 705
1-1/4 360 490 450 610 530 720 710 965
1-3/8 480 650 600 815 710 965 950 1290
1-1/2 620 840 770 1045 920 1250 1230 1670
1-3/4 950 1290 1190 1615 1420 1925 1890 2565
2 1470 1990 1830 2480 2200 2980 2930 3970
2-1/4 2130 2890 2670 3620 3200 4340 4270 5970
2-1/2 2950 4000 3650 4950 4400 5970 5850 7930
2-3/4 3950 5360 4900 6640 5900 8000 7850 10640
3 5150 6980 6400 8680 7700 10440 10250 13900
Observe the following when using this Torque Table:
 All information and instructions given under Paragraph 5-3. TIGHTENING

REQUIREMENTS must be thoroughly reviewed before applying the specified torque
values.
 The torque values are based on a common petroleum type oil lubricant.
 The torque values are applicable to both National Fine and National Course thread
series. Any difference in the torque values because of the thread series is within the
normal variation if the torque wrench accuracy.
 When tightening fasteners that incorporate a self-locking feature, a certain amount of

the applied torque is lost because of the additional friction of the locking feature. Use a
torque wrench to measure the “run-down” torque and then add it to the listed torque
value.
5-10
5-3.8. Frame and Running Gear Bolting
Table 5-5. HOSS Torque Wrench Values 1

Thread At = Thread Tensile Area
Bolt or Stud Size Distance Required Torque Torque

Location & Pitch Across Pre-
(inches) Flats (in) Stress (Ft-lbs) (N•m)
(PSI)
Frame Tie Rod 1.750- 40 000 2 2
2-3/4
Studs 8UNR-3A Thread At
Main Bearing Cap 0.875- 40 000
1-7/16 240 325
Studs 9UNC-3A Thread At
Thrust Bearing 0.375- 40 000
7/32 Hex 19 26
Capscrews 16UNC-2A Thread At
Connecting Rod 1.250- 1-1/4 40 000 0.014 to 0.013 in 3
Cap Bolts 12UNJF-2A 12 pt Thread At (0.36 to 0.33 mm)
Crosshead Pin 0.500- 40 000
3/4 44 60
Cap Bolts 13UNC-2A Thread At
Crosshead Shoe 0.500- 40 000
3/8 Hex 44 60
Cap Bolts 13UNC-3A Thread At
Crosshead
0.750- 40 000
Balance Weight 1-1/4 152 206
10UNC-3A Thread At
Cap Bolts
Frame 1.500- 4
2-3/8 ---- ----
Foundation Bolts 8UNR-3A
Oil Pump 0.500- 40 000
3/4 44 60
Mounting Bolts 13UNC-2A Thread At
Oil Pump Drive 0.375- 40 000
3/16 19 26
Hub Setscrew 16UNC-3A Thread At
Oil Slinger 0.375- 40 000
3/16 19 26
Capscrews 16UNC-3A Thread At
Cylinder/Distance
1.500- 40 000
Piece Tie Rod 2-3/8 1230 1670
8UN-3A Thread At
Studs
Crosshead Lock 2.750- 5 5
4-1/4 ----
Nut 8UNJ-3A
Aluminum Piston 2.500- 6 6
---- ----
– Piston Rod 8UNJ-3A
Nodular Iron 1.72x
2.500- N/A See SUPERBOLT
Piston – Piston MACCRL
8UNJ-3A Supernut Torque Table
Rod =29,040
NOTES:
1
= Torque wrench values are based on common mineral oil thread lubricants.
2
= See Paragraph 4-5.2. Step 12 for the frame tie rod nut tightening procedure.
3
= Stretch method is required for this fastener.
4
= See Paragraph 5-3.5 for the proper pre-stress value for these fasteners.
5
= See Paragraph 4-13 Step 5 for the crosshead lock nut tightening procedure.
6
= See Paragraph 4-12.5 for the piston nut tightening procedure.
5-11
Form PG-2818-L
May, 2008
Instruction Supplement
SUPERBOLT® TORQUE NUTS

for
COMPRESSOR PISTONS
AND CROSSHEADS
Paragraph Page
GENERAL DESCRIPTION ................................................................................................ 1

CROSSHEAD NUT APPLICATION ................................................................................... 3
PISTON NUT APPLICATION............................................................................................. 8
LOOSENING THE TORQUE NUT ..................................................................................... 9
GENERAL DESCRIPTION
Some compressor piston rods are fitted with a special multi-bolt torque nut instead of the
standard hex-type jam nut to fasten the piston rod to the crosshead or the piston to the piston
rod. These applications are illustrated in Figures 1 and 3. This instruction form is to be used in
conjunction with the piston and rod installation procedure and the crosshead removal procedure
found in the Maintenance Section of the compressor job-specific Service Manual.
The Superbolt® torque nut is threaded onto the piston rod with a washer positioned
between the crosshead or piston and the torque nut, as shown in Figures 1&3. Once the torque
DANGER
Never use a petroleum-based lubricant with oxygen
equipment. A mixture of oxygen with petroleum-based
lubricants is violently explosive and could cause property
damage, personal injury or death.
WARNING
Compressor cylinders must be depressurized to
atmospheric pressure before working in the frame interior.
Compressor pistons will move to bottom-dead-center as an
equilibrium condition due to the difference in piston surface
area (by piston rod cross sectional area) exposed to the
process gas pressure. Failure to depressurize the
compressor cylinders prior to working may result in
unexpected rollover that can cause personal injury.
PG-2818-L SUPERBOLT® TORQUE NUTS
WARNING
Before working in the frame interior, ensure the compressor
is blocked against accidental roll-over and that the prime
mover is locked out and is tagged with a sign bearing the
legend "WORK IN PROGRESS - DO NOT START".
WARNING
Previous versions of these nuts may use a different jackbolt
thread lubricant, or number of jackbolts and therefore
require a different torque value. The pre-load applied when
using different thread lubricants will vary significantly.
ALWAYS USE THE TORQUE VALUE AND TYPE OF THREAD
LUBRICANT STAMPED ON THE NUT O.D. If there is a
discrepancy, contact Dresser-Rand Recip Technical Support
at 1-607-937-2626 for tightening specifications. Failure to
achieve the proper pre-load value based on the type of
thread lubricant can lead to an improperly tightened joint.
CAUTION
The torque nut is shipped with pre-lubricated jackbolts. The
jackbolt lubricant and torque value is stamped on the torque
nut O.D. DO NOT re-lubricate the jackbolts upon arrival of
the torque nut. If the jackbolts do not appear to be
lubricated, contact Dresser-Rand Recip Technical Support at
1-607-937-2626 immediately.
CAUTION
If the jackbolts must be cleaned or re-lubricated, they MUST
be lubricated with the type of lubricant stamped on the
torque nut O.D. The jackbolts torque value is based
exclusively on this lubricant. Consult with Dresser-Rand
Recip Technical Support at 1-607-937-2626 if you should
desire to change the jackbolt lubricant. Newer versions of
the torque nuts are lubricated with Dow Corning® G-n Metal
Assembly Paste. These versions are stamped "G-n" on the
torque nut O.D. Dow Corning® G-n Metal Assembly Paste is
available through most commercial suppliers. Previous
versions of these torque nuts were lubricated with
Superbolt® JL-M moly based lubricant, and are stamped "JL-
M" on the torque nut O.D. Superbolt® JL-M is only available
through Superbolt®.
2
SUPERBOLT® TORQUE NUTS PG-2818-L
If no jackbolt thread lubricant designation is stamped on the

torque nut O.D.; either it is an older (pre-1992) torque nut
and the jackbolts were lubricated with mineral oil or
Superbolt® JL-CN grease, or the jackbolts were lubricated
with Superbolt's® standard JL-G graphite based lubricant. If
the D-R part number is stamped on the torque nut O.D.,
contact Dresser-Rand Recip Technical Support at 1-607-937-
2626 to determine the correct jack bolt thread lubricant and
torque value.
CAUTION
When working with stainless steel piston rods, a
commercially available molybdenum disulfide (MoS2) based
lubricant known as Dow Corning® G-n Metal Assembly
Paste should be used when screwing the crosshead nut
onto the piston rod, the piston rod into the crosshead and
the piston nut onto the piston rod. Lubricants equivalent in
chemical make up and nut factor may still allow galling of
the components.
CROSSHEAD TORQUE NUT APPLICATION
DANGER
DANGER! WARNING! and CAUTION! Alerts, appearing
in the General Description Section of this instruction
form should be thoroughly reviewed and understood
before proceeding any further. The information in
these alerts is of paramount importance to maintain
personal and equipment safety.
Figure 1. Crosshead Torque Nut Application
3
1. The condition of the face of the crosshead nose is very important. Any burrs or surface
damage can degrade the effectiveness of the fasteners. Burrs and all other surface
damage should be removed with an oilstone to ensure the surface is flat.
2. Before screwing the piston rod into the crosshead, clean the piston rod threads,
crosshead threads and the main threads in the torque nut body. Then lightly lubricate
by applying a small amount of Dow Corning® G-n Metal Assembly Paste and spreading
it evenly over piston rod threads.
3. Clean the flat washer supplied with the torque nut. Install the washer and torque nut
onto the piston rod.
CAUTION
Take every precaution during piston and piston rod
installation to avoid scratching or nicking the piston rod
surface. Even a slight nick in the rod can ruin the pressure
packing or oil scraper rings.
CAUTION
Never use a pipe wrench, or any other tool that can scratch
or otherwise damage the piston rod. Most pistons are
drilled and tapped which will allow a tee bar-type wrench to
be attached to the outer face of the piston to turn the piston
and rod assembly. Where this is not possible, a mechanical
strap (Parmalee®) wrench is recommended to turn the rod.
SERVICE NOTE
It may be helpful to utilize a piston rod support tool (DR Part No:
MLG14403G1) under the piston rod to facilitate
installation/removal. Adjusting the height of the piston rod with
the aid of this tool will help support the weight of the rod and
prevent galling of the mating threads as the rod
engages/disengages the crosshead. Dresser-Rand can provide
this piston rod support tool to facilitate installation/removal.
4. As shown in Figure 1, screw the rod into the crosshead, using a tee bar-type wrench to
be attached to the outer face of the piston, or use a mechanical strap wrench until the
required piston frame end clearance is obtained. (Refer to the job-specific Service
Manual for piston frame end clearance procedure.) If required, turn the piston rod
slightly, so that the dowel can be inserted through the crosshead and the slots in the
piston rod.
5. Before tightening the crosshead nut jackbolts; use one (#1) or two (#2 & #3) dial
indicators, (See Figure 2.) depending upon the situation, to center the external piston
rod thread vertically in the internal crosshead thread, instead of relying on the tightening
of the crosshead nut jackbolts to do this.
4
1. Dial Indicator
2. Dial Indicator
3. Dial Indicator
4. Crosshead
5. Piston Rod
6. Jackscrew
7. Xhead Shoes
8. Xhead Guide
Figure 2. Centering Piston Rod Threads in the Crosshead Threads
5.1. One dial indicator (#1) - if access to the face of the crosshead (#4) is
unobstructed.
5.1.1. With the piston rod screwed into the crosshead nose, attach a dial
indicator (#1) magnetic base to the crosshead (#4). Position the gauge
90º to the horizontal top surface of the piston rod (#5).
5.1.2. Set the dial to “0”.
5.1.3. To measure the piston rod-to-crosshead pitch line clearance use either a
D-R piston rod support tool (MLG14403G1) or a very small screw jack
(#6) and lift the piston rod till it contacts the top threads in the crosshead.
5.1.4. Take the dial indicator reading.
5.1.5. To check the indicator, lower the piston rod as far as it will go and check
the reading. It should read “0”.
5.1.6. Lift the piston rod ½ of the measured pitch line clearance. (½ the
distance read on the dial indicator when the piston rod was raised to the
maximum.)
5.2. Two dial indicators (#2 & #3) - if access to the face of the crosshead is
obstructed.
5.2.1. With the piston rod screwed in to the crosshead nose attach a dial
indicator (#2) to the upper crosshead guide (#8). Set the indicator
making contact 90º with the horizontal top surface of the piston rod (#5).
5.2.2. Set up the second indicator (#3) with the magnetic base on the lower
crosshead guide (#8) and the indicator on the upper surface of the lower
crosshead shoe (#7).
5.2.3. Zero both indicators.
5
5.2.4. To measure the piston rod-to-crosshead pitch line clearance use either a
D-R piston rod support tool (MLG14403G1) or a very small screw jack
(#6), lift the piston rod until the lower indicator needle just starts to move.
5.2.5. Take the upper dial indicator reading.
5.2.6. To check the indicator, lower the piston rod as far as it will go. It should
read “0”.
5.2.7. Lift the piston rod ½ of the measured pitch line clearance. (½ the
distance read on the upper dial indicator when the piston rod was raised
to the top.)
nut body.
CAUTION
Steps 7 through 14 are extremely important. If the proper
procedure is not followed, the crosshead/piston rod
connection can be distorted and crosshead can lift off the
lower guide.
NOTE
On some crosshead guides having only one side cover, it will be

necessary to use a torque adapter to reach the jackbolts on the
backside of the piston rod.
7. Hand-tighten the torque nut against the crosshead, but do not tighten the jackbolts at
this time.
8. Using a 0.0015 inch (0.04mm) feeler gauge, measure between the nose of the
crosshead and the torque nut washer to ensure that the washer is making metal-to-
metal contact with the crosshead.
9. Using a 0.0015” feeler gauge, probe between the bottom crosshead shoe and the lower
guide at the 6 o'clock position at both ends of the shoe, to ensure the crosshead is
setting evenly on the lower guide. Measure the crosshead-to-lower guide clearances at
the four corners to be certain that the crosshead is not cocked in the guide.
10. Hand tighten the jackbolts gently, following the appropriate star pattern as indicated in
Figure 4 based on the number of jackbolts, so as to tighten them against the washer but
not move the torque nut. Check between the torque nut body and washer all the way
around with a feeler to make sure the nut body has not been moved away from the
washer while hand tightening the jack bolts.
6
11. Torque the jackbolts to 5% of the final torque value stamped on the torque nut O.D.
Tighten the jackbolts following the appropriate star pattern as indicated in Figure 4
based on the number of jackbolts, unless otherwise indicated on the torque nut.
11.1. Using a feeler gauge, measure and record the clearance between the torque nut
and washer at 3, 6, 9, and 12 o'clock positions.
11.2. Once you find the lowest clearance reading of the four, check further around that
part of the circumference to locate the smallest clearance.
11.3. Recommence tightening the jack bolts at the location identified in step 11.2.
11.3.1. If it is an odd numbered bolt, follow the ascending numbers in the

appropriate star pattern, as indicated in Figure 4 based on the number
of jackbolts, returning to the number with which you began.
11.3.2. If it is an even numbered bolt, follow the descending numbers in the

appropriate star pattern, as indicated in Figure 4 based on the number
of jackbolts, returning to the number with which you began.
NOTE
If at the completion of any step a recorded clearance is 0.003

inch (0.08mm) greater than any of the other three clearances,
and stays greater than 0.003 inch (0.08mm) after completion of
the next step, loosen the jackbolts and start over again at Step
10.
12. Starting at the position where the smallest clearance was recorded in Step 11, tighten
the jackbolts to 10% of the final torque value following the appropriate star pattern.
Repeat Steps 11.1, 11.2 and 11.3.
the jackbolts to 75% of the final torque value following the appropriate circular pattern.
16. Starting at the position where the smallest clearance was recorded in Step15, tighten
the jackbolts to 100% of the final torque value, again using the appropriate circular
pattern.
17. Repeat Step 16 three to four times or until the jackbolts do not rotate farther upon re-
torquing.
7
18. Using a 0.0015 inch (0.04mm) feeler gauge, probe between the bottom shoe and the
lower guide at the 6:00 o'clock position at both ends of the shoe to ensure the
crosshead is resting on the lower guide; the feeler should NOT enter. Also, measure
the crosshead-to-lower guide clearances at the four corners of the shoe to be certain
that the crosshead is not cocked in the guide. If the crosshead is not resting squarely
on the lower guide, loosen the jackbolts (refer to loosening procedure which follows)
and repeat Steps 10 through 17.
PISTON TORQUE NUT APPLICATION
DANGER
DANGER! WARNING! and CAUTION! Alerts, appearing
these alerts is of paramount importance to maintain
1. Chuck the piston rod in a hollow spindle lathe or clamp the rod down on a milling
machine bed or a worktable. In all cases, use a soft bearing material next to the rod
surface. Clamp the rod immediately behind the rod collar.
2. Assemble the piston onto the rod as shown in Figure 3. Check the seating surfaces
between the piston rod collar and piston by "bluing" to assure that at least 85 percent of
evenly distributed seating contact is made on all contact surfaces. If necessary, lap the
faces using lapping compound. Remove all traces of lapping compound, using soap
and hot water.
Figure 3. Piston Torque Nut Application
8
3. Before screwing the torque nut onto the piston rod, clean the piston rod threads and the
main threads in the torque nut body. Then lightly lubricate by applying a small amount of
Dow Corning® G-n Metal Assembly Paste and spreading it evenly over the piston rod
threads.
nut body.
5. Clean the flat washer supplied with the torque nut. Install the washer and torque nut
body onto the piston rod.
6. Screw the torque nut body onto the rod as tight as possible by hand. (Make sure the nut
is bottomed in the counterbore before tightening jackbolts.)
7. Tighten the jackbolts to 10% of the final torque value stamped on the torque nut O.D.
following the appropriate star pattern shown in Figure 4, unless otherwise indicated on
the torque nut.
8. Tighten the jackbolts to 25% of the final torque value following the appropriate star
pattern.
9. Tighten the jackbolts to 50% of the final torque value following the appropriate star
pattern.
10. Tighten the jackbolts to 75% of the final torque value following the appropriate circular
pattern.
11. Tighten the jackbolts to 100% of the final torque value, again following the appropriate
circular pattern.
12. Repeat Step 11 three to four times, or until the jackbolts do not advance anymore, upon
further torquing.
TORQUE NUT LOOSENING
DANGER
DANGER! WARNING! and CAUTION! alerts appearing
these alerts, is of paramount importance to maintain
9
Caution
Removal requires strict procedures! Jackbolts must be
unloaded gradually. If some jackboots are fully unloaded
prematurely, the remaining jackbolts will carry the entire
load and may be hard to turn. With extreme abuse, a
jackbolt tip can deform making removal difficult.
Service Under 250˚F
1. Spray the jackbolts with penetrating oil or hydraulic oil prior to beginning loosening
process.
2. Loosen each jackbolt 1/8 turn following a circular pattern around the tensioner. (1 round
only) As you move around and get back to the first jack bolt, it will be tight again. Do
this for all jackbolts on the joint prior to the next step.
3. Repeat a second round as in step 2 for all jackbolts, loosening each jackbolt ¼ turn in a
circular pattern.
4. Continue loosening ¼ turn for a 3rd and successive rounds until all jackbolts are loose.
NOTE
Usually after the 3rd or 4th round, an impact wrench can be used
to completely extract the jackbolts, one by one. For long bolts or
tie rods, additional rounds may be required before removing the
jackbolts with an impact tool.
5. Remove, clean and re-lubricate the jackbolts prior to next use with correct Superbolt
lubricant as stamped on the nut.
Service Over 250˚F
NOTE
Above 300˚F the petroleum base of the lubricant burns off. Oil
per “Step 1” below to reduce to the removal torque.
1. As the equipment is cooling down (around 300˚F), apply hydraulic oil to the jackbolts
and washers and let sit for several hours. Thoroughly “wet-down” all components and
re-apply during equipment cool down period. If the tensioner is inverted, squirt oil in the
gap between the nut body and the washer. Synthetic oil can be used for oiling above
300˚F.
2. Wait for tensioners to cool below 200˚F. Using a circular pattern, “crack” each jackbolt
only enough to ensure movement. Do not turn beyond the break loose point. Do this
for all jackbolts.
3. Now begin with “STEP 1” of the procedure for service under 250˚F.
10
Figure 4. Torque Nut Tightening/Loosening Sequence
11
Figure 4 (Cont'd). Torque Nut Tightening/Loosening Sequence
12
PARTS LIST
GFC ORDER C-2314

(121955/90032109)
CONTENTS
ORDERING REPLACEMENT PARTS .................................................................. PG-3832-B
REPORTING DEFECTIVE PARTS ....................................................................... PG-707-C
FRAME & GEAR PARTS ...................................................................................... TAB 'A'
15.0-INCH CYLINDER PARTS ............................................................................. TAB ‘B’
9.50-INCH CYLINDER PARTS ............................................................................. TAB ‘C’
SHIP LOOSE KIT .................................................................................................. TAB ‘D’
SPARES ................................................................................................................ TAB ‘E’

Form PG-3832-B
February, 2012
How to order replacement parts...

WARNING
The use of repair parts other than those included
within the Dresser-Rand approved parts list may
create hazardous conditions over which the
company has no control. Such hazardous
conditions can lead to accidents that may be life-
threatening, cause substantial bodily injury, or
result in damage to the equipment.
When ordering replacement parts, please specify:
1. The SERIAL NUMBER as stamped on the machine nameplate.
2. The QUANTITY desired and the PART NAME and PART NUMBER, exactly as listed.
Careful observance of the following will help us to fill your order correctly and promptly:
 THE MACHINE SERIAL NUMBER MUST BE GIVEN WITH EVERY ORDER FOR PARTS. This
number will be found on a nameplate attached to the unit. It consists of a combination of letters and
numerals (Example: YRS312, YRH590, Y6R565, A17922). The serial number is often permanently
stamped in the metal near the nameplate location.
 DO NOT use such terms as "complete" and "sets" unless these words appear specifically in the
Parts List. State quantity wanted and give the part number and part name exactly as shown in the
Parts List. DO NOT use illustration numbers when ordering parts.
 When ordering spares for parts not manufactured by Dresser-Rand Company, such as Lubricators,
Magnetos, Oil Pumps, Governors, etc., always give the serial or type numbers of these parts as well
as the Dresser-Rand machine serial number. This will enable us to more quickly send the correct
material, as manufacturers often make changes over which we have no control.
 If returning parts for inspection or repair, be sure to include the serial number of the machine from
which the parts were removed.
1
Parts Ordering Instructions PG-3832-B
How to use approved parts lists...

PARTS LIST INDEX
The assemblies and major subassemblies comprising the complete unit are listed in the index in
the order in which they are displayed and broken down in the Parts List. The Part Number for each
assembly and major subassembly listed in the index appears at the top right corner of the Parts List
which lists the subassemblies and individual parts of that assembly.
PARTS LIST
The Parts List contains the listings and illustrations of the parts for your unit. Interpretation of
the Parts List is described on the next page.
NOTE
Some illustrations may have illustration numbers which do not

appear in the Parts List. This simply means those parts are not
used on your unit.
A plus (+) sign next to a part name indicates that sub-manufacturer's literature for that part is
available elsewhere in the Service Manual. A notation at the bottom of the parts list page calls
attention to this fact.
RECOMMENDED SPARE PARTS DATA
The spare parts data shown in the Spares Usage Code column of the Parts List identifies for
you those Spare parts which you may require in the maintenance of the Dresser-Rand equipment.
It is desirable to forecast as accurately as possible your requirements for Spare Parts to assure
that the necessary parts and materials will be available when needed to keep your equipment in
efficient and continuous operating condition.
We feel that you are in a better position than we to decide how much you wish to invest in
Spare Parts. The importance of minimizing shut-down time due to possible breakdowns in
operation, together with the distance from source of supply and transportation facilities, should be
considered when ordering spare parts.
MAINTAIN THE MAXIMUM OPERATING CHARACTERISTICS AND

DEPENDABILITY OF YOUR EQUIPMENT BY USING GENUINE DRESSER-
RAND SPARE PARTS.
2
PG-3832-B Parts Ordering Instructions
How to interpret parts list columns...
PISTON & ROD  MLH43705CG1 
K UNITS UM SPARES
ILLUS. PART NUMBER PART NAME I PER NE USAGE
NO.   T ASSEMBLY I A CODE
   T S 

 Part name and number for the total assembly. Includes all parts listed.
 ILLUSTRATION NUMBER column. The illustration number is the item number

assigned to the part in the listing. The illustration number identifies the part on the
associated illustration. When a parts list has no illustration, this column will be blank.
 PART NUMBER column. All numbers shown are Dresser-Rand part numbers. The
relationship of a part to its next higher assembly is indicated by indenture in the Part
Number column. An included item is denoted by indenture under the item with which is
included. For example:
PART NUMBER PART NAME Note: When ordering any part having an indented line or lines
following the part, the indented items are always included with
.1H28571A Liner the part. Indented items may also be ordered separately.
. .W54857A O-ring
. .W81556 Gasket
 PART NAME column. This column contains noun-names with major modifiers. When
ordering an item, give the part name exactly as shown.
 KIT CODE column. This column indicates parts that are included in one or more kits.
Code Definition
G Item included in a Gasket Set.
 UNITS PER ASSEMBLY column. The quantities specified in this column indicate the
number of parts used per next higher assembly and are not necessarily the total number
used in the complete unit.
 UNITS OF MEASURE column. This column designates what unit of measure is

applicable for a particular part number. For example:
PC = piece HA = halves SI = square inch

IN = inchGA = gallons SF = square feet
FT = feet LB = pounds QT = quarts
 SPARES USAGE CODE column. This column identifies parts that are recommended
under one or more of five classes of spare parts.
Code Definition
R Parts normally used during routine maintenance.
O Parts normally used for overhaul.
C Parts for convenience in minimizing down time at overhaul.
E Insurance items normally used over an extended period.
M Insurance items required for major failure, otherwise not likely to be used.
3
Parts Ordering Instructions PG-3832-B
Sales Support Operation...
DRESSER-RAND
Gas Field Products
1354 S. Sheridan Rd.
Tulsa, OK 74112
New Equipment Marketing

After Market Services
Phone: (918) 254-4099

Fax: (918) 252-9055
Parts Order Line

1 (800) 721-4271
Parts 24-hour Hot-Line

1 (716) 378-4486
4
Form PG-707-C
April, 1995
Reporting Defective Parts...

It is recognized by the Dresser-Rand Company that there are instances where service
parts are received at the job site unsuitable for use. There are numerous causes that can be
responsible for such defects, which can occur before shipment, during transit, or upon being
received, handled and stored at the destination. In an attempt to eliminate this problem as much
as possible, the Dresser-Rand Services Division is requesting information on any defective parts
received in a Service Order. A special "Defective Parts Report" has been prepared for this
purpose and outlines the information needed to properly research the problem; a copy of this form
is reproduced on the back side of this page.
We encourage our customers to utilize this form in reporting defective parts. Instructions
for filling in the required information and the mailing address for the completed report are included
on the report form. Duplication of the form as required is authorized by Dresser-Rand Company.
DEFECTIVE PARTS REPORT
(Make a separate report for each different part)
The purpose of this report form is to alert the Group of potential quality problems of stocked parts. For this
form to be effective, it must be completed, as much as possible, and sent to Dresser-Rand Services
Division, Painted Post, NY 14870 the day the defect is noted or reported. Information not readily available
should be mailed when obtained. Do not hold the report until you get this information. The follow-up report
should be a copy of the original with the added information.
Customer Location
Type of equipment S/N (if applicable)
Date defect reported Defective part no.
Date part received by customer Part Description
D-R Control No . covering part Number of pieces involved
Parts Received from (check one):
Chicago Regional o Midland o Branch (Specify) o

New Orleans Regional o Houston Regional o Vendor (Specify) o
L.A. Regional o D-R Factory (Specify) o
When was defect noted (check one):
At time part was received o When part was being installed o

After part had been operated o
Description of defect:
Probable cause of defect (check applicable reasons):
Improper machining o Design o

Improper installation o Improper packaging o
Shipping damage o Improper preservation for long-term storage o
Other (explain):
Resolution of defective part (check):
Repaired o Scrapped o Returned for new part o

Returned for credit o
Other (explain):
CSD Number, if applicable CSD-
Reported by Location
(D-R Office, Shop, etc.)
Date
PG-707-C, pg. 2 Does not replace CSD, MRR or Credit Reports

Report Date: 23 January 2013
PARTS LIST
Assembly Item Rev Assembly Item Description Drawing/Illustration
7SHF162 002 SN: 7SHF162 MODEL: FRAME 7HOSS4
Designator/Illus BOM Item Number Item Description Qty UOM Service Level
Number Level
1 MLAIZK0401G3 FRAME & GEAR 7HOSS4 1 EA
1 MLQHHA0489G1 LUBRICATION SYSTEM 1 EA ....M
1 MLW140338EG7 WEIGHT XHD BAL 2 EA
1 MLXAZK0401G1 KIT BALANCE 1 EA
1 W151744AX4X1 CLAMP TUBE - 1/4" X 1 TUBE 10 EA
1 35A2D1 CAPSCREW 16 EA
1 610116E10 CLIP TWO TUBE 6 EA
© 2013 DRESSER-RAND COMPANY 7SHF162

Report Date: 19 November 2012
PARTS LIST
MLAIZK0401G3 001 FRAME & GEAR 7HOSS4 NONE
Number Level
1 MLH65316G1 CONNROD COMPRESSOR 4 EA
1 MLH65320G1 CRANKSHAFT 1 EA
1 MLH65322G1 CROSSHEAD 4 EA
1 MLH65330G1 COVER DRIVE END 1 EA
1 MLH65341G1 PUMP OIL 4 THROW 1 EA
1 MLH65386G1 HEADER OIL STRAINER 1 EA
1 MLH65390G1 FRAME 4 CYL 1 EA
1 MLH65408G1 PIPING FRAME OIL 1 EA
1 MLH65411AG1 COVER PRELUBE PUMP 1 EA
1 R88716 NAMEPLATE FRAME 1 EA
© 2012 DRESSER-RAND COMPANY MLAIZK0401G3

PARTS LIST
4 CYLINDER FRAME ASSEMBLY
H65390, REV. B
PARTS LIST
MLH65390G1 002 FRAME 4 CYL H65390
Number Level
001 1 MLH65389G1 FRAME 4CYL BARE 1 EA
002 1 12592416 BOX CRANKPIN 4 EA .O..E.M
003 1 MLH65369G1 COVER PUMP END TOP 1 EA
004 1 H65376 GASKET CVR PUMP END 1 EA R.O.C.E.M
005 1 MLH65370G1 COVER SPACER BAY 1 EA
006 1 H65377 GASKET FR TOP BAY 1 EA
007 1 MLH65371G1 COVER FR TOP ROD BAY 2 EA
008 1 H65378 GASKET FR TOP CVR ROD BAY 2 EA R.O.C.E.M
009 1 MLH65372G1 COVER DRIVE END 1 EA
010 1 H65379 GASKET FR TOP CVR DR END 1 EA R.O.C.E.M
011,014,017 1 35A2D217 CAPSCREW 279 EA
012 1 MLH65373G1 COVER FR EXT SIDE 8 EA
013 1 H65380 GASKET FR EXT SIDE CVR 8 EA R.O.C.E.M
015 1 R71929A CAP OIL HDR HOSS 1 EA
016 1 R88770 GASKET 1 EA R.O.C.E.M
018 1 32A7S2 PLUG ROUND HEAD 1 EA
019 1 W82537 GAUGE OIL LEVEL 1 EA ....M
020 1 65A7M9 ELBOW 90 DEGREE 1 EA
021 1 31A7C10 PLUG SQUARE COUNTERSUNK 1 EA
022 1 W82559 BREATHER FR RDS HOS 1 EA .O..E.M
023 1 122A2S57 DRIVESCREW 4 EA
024 1 20A11CM279 ORING 4 EA R.O.C.E.M
026 1 2SCH80J5.7C NIPPLE 1 EA
© 2012 DRESSER-RAND COMPANY MLH65390G1

PARTS LIST
4CYLINDER FRAME (BARE) ASSEMBLY
H65389, REV. B
PARTS LIST
MLH65389G1 001 FRAME 4CYL BARE H65389
Number Level
001 1 G15049 FRAME 4 HOSS 1 EA
005 1 1H65333P1 CAP MAIN BRG REPAIR 4 EA
006 1 R88501 SHOE THRUST 2 EA .O..E.M
007 1 139A2Z200 CAPSCREW 8 EA
008 1 R78164VX07031 STUD 16 EA
009 1 38A4K9 NUT 16 EA
010 1 R88499 SPACER MB TIEROD 4 EA
011 1 R78164MX14132 STUD 4 EA
012 1 X1016T8 WASHER 8 EA
013 1 W30980 NUT TIE ROD 8 EA
015 1 W29804A BOLT LOCK 8 EA
016 1 00143C PLUG PIPE 2 EA

PARTS LIST
CRANKSHAFT ASSEMBLY
H65320, REV. B
PARTS LIST
MLH65320G1 001 CRANKSHAFT H65320
Number Level
001 1 G15041 CRANKSHAFT 7HOSS4 1 EA
002 1 17A13A208 DOWEL PIN 2 EA R.O.C.E.M
003 1 H65327P2 COUNTERWEIGHT 2 EA
004 1 17A13A466 DOWEL PIN 1 EA
005 1 1H61734D RING CRANKSHAFT OIL 1 EA
006 1 119A2A204 CAPSCREW 2 EA

PARTS LIST
DRIVE END COVER ASSEMBLY
H65330, REV. 01
PARTS LIST
MLH65330G1 002 COVER DRIVE END H65330
Number Level
001 1 F43301 COVER DRIVE END 1 EA
002 1 H65329 GASKET FR D E 1 EA R.O.C.E.M
003 1 25A13C293 ROLLPIN 2 EA R.O.C.E.M
004 1 R78164VX04013 STUD 2 EA
005 1 38A4K5 NUT 2 EA
006 1 35A2D220 CAPSCREW 16 EA
007 1 W118658P7 SEAL CRANKSHAFT 1 EA ..C.E.M
008 1 R88498 RETAINER SEAL 1 EA

PARTS LIST
CONNECTING ROD ASSEMBLY
H65316, REV. 02
PARTS LIST
MLH65316G1 002 CONNROD COMPRESSOR H65316
Number Level
001 1 1G15040 ROD CONNECTING 1 EA
002 .2 R86223A BOLT CONNROD 4 EA ...E.M
003 .2 17A13A287 DOWEL PIN 2 EA R.O.C.E.M
004 .2 H65313 BUSHING CONNROD 1 EA .O..E.M
005 1 12592416 BOX CRANKPIN 1 EA .O..E.M
006 1 X1636T062 LOCKWIRE STL .062 24 IN
007 .2 W86526A WASHER BOLT NUT 4 EA

PARTS LIST
CROSSHEAD ASSEMBLY
H65322, REV. A
PARTS LIST
MLH65322G1 001 CROSSHEAD H65322
Number Level
001 1 F43292 CROSSHEAD 1 EA ....M
002 1 H65318 PIN CROSSHEAD 1 EA ...E.M
003 1 W139376C DOWEL PIN 1 EA
004 1 R88489 CAP PIN CROSSHEAD 2 EA
005 1 35A2D217E CAPSCREW 8 EA
006 1 H65317 SHOE CROSSHEAD 2 EA .O..E.
009 1 1R88492 SHIM XHD SHOE 4 EA .O..E.M
010 1 108A2A28 SET SCREW HEX SKT 8 EA ...E.M

PARTS LIST
4 THROW OIL PUMP ASSEMBLY
H65341, REV. C
PARTS LIST
MLH65341G1 003 PUMP OIL 4 THROW H65341
Number Level
1 MLH65341P1G1 KIT REBUILD HOSS4 1 EA
1 MLH65341P2G1 KIT OVERHAUL HOSS4 1 EA
001 1 1G15056 COVER PUMP END 1 EA
002 .2 W31371P1 BUSHING OIL PUMP 2 EA .O..E.M
003 1 1H65344A PUMP BODY 4 THROW 1 EA
005 1 W73193A GASKET 2 EA R.O.C.E.M
006 1 1H53637 HEAD OIL PUMP 1 EA
007 1 12629663 KIT GASKET PUMP 1 EA
008 1 17A2C1109 BOLT HEX 8 EA
009 1 1R12972P2 GEARS PR OP RDS HOS 1 EA
012 1 23A9C807 KEY 3 EA
013 1 11A9C83 KEY SQUARE 1 EA
014 1 W86236C HUB OIL PUMP 1 EA .O..E.M
016 1 H65345 GASKET FR OPE CVR 1 EA R.O.C.E.M
017 1 25A13C400 ROLLPIN 2 EA
020 1 W83585 COVER LUB HOLE 1 EA
021 1 W83586 GASKET 1 EA R.O.C.E.M
023 1 W71539 NAMEPLATE ROTATION 1 EA
024 1 122A2S78B DRIVESCREW 4 EA
025 1 W73193B GASKET 2 EA R.O.C.E.M

PARTS LIST
4 THROW OIL PUMP REBUILD KIT
H65341P1
PARTS LIST
MLH65341P1G1 001 KIT REBUILD HOSS4 H65341P1
Number Level
002 1 R44267B SHAFT DRIVE RH 1 EA
003 1 W83550 SHAFT PUMP DRIVEN 1 EA
004 1 23A9C807 KEY 3 EA
006 1 W31371P1 BUSHING OIL PUMP 4 EA .O..E.M
008 .2 H65345 GASKET FR OPE CVR 1 EA R.O.C.E.M
009 .2 W83586 GASKET 1 EA R.O.C.E.M
010 .2 W73193A GASKET 2 EA R.O.C.E.M
011 .2 W73193B GASKET 2 EA R.O.C.E.M
012 .2 32A11C6 GASKET 1 EA R.O.C.E.M
015 .2 20A11CM328 ORING 1 EA R.O.C.E.M
© 2013 DRESSER-RAND COMPANY MLH65341P1G1

PARTS LIST
4 THROW OIL PUMP OVERHAUL KIT
H65341P2
PARTS LIST
MLH65341P2G1 001 KIT OVERHAUL HOSS4 H65341P2
Number Level
002 1 R44267B SHAFT DRIVE RH 1 EA
002 .2 W31371P1 BUSHING OIL PUMP 2 EA .O..E.M
003 1 W83550 SHAFT PUMP DRIVEN 1 EA
004 .2 17A13A208 DOWEL PIN 4 EA R.O.C.E.M
004 1 23A9C807 KEY 3 EA
006 1 W31371P1 BUSHING OIL PUMP 2 EA .O..E.M
008 .2 H65345 GASKET FR OPE CVR 1 EA R.O.C.E.M
009 .2 W83586 GASKET 1 EA R.O.C.E.M
010 .2 W73193A GASKET 2 EA R.O.C.E.M
011 .2 W73193B GASKET 2 EA R.O.C.E.M
015 .2 20A11CM328 ORING 1 EA R.O.C.E.M
016 1 1H65344A PUMP BODY 4 THROW 1 EA
018 1 1H53637 HEAD OIL PUMP 1 EA
020 1 17A2C1109 BOLT HEX 8 EA
© 2013 DRESSER-RAND COMPANY MLH65341P2G1

PARTS LIST
FRAME OIL PUMP PIPING
H65408, REV. G
PARTS LIST
MLH65408G1 004 PIPING FRAME OIL H65408
Number Level
001 1 MLH65351G1 PIPING OIL PMP SUCT 1 EA
002 1 ML66972G7 BOLTING FLANGE 1 EA
003 1 32A11C8 GASKET 1 EA R.O.C.E.M
005 1 R88502BT2 ELEMENT FILTER OIL 1 EA
006 1 W93317B VALVE PRESS CONTROL 1 EA ....M
008 1 MLH65467G1 PIPING PUMP DISCH 1 EA
011 1 1R88502B KIT OIL FILTER 1 EA
012 1 H65449 SUPPORT FILTER 1 EA
014 1 38A4K5 NUT 4 EA
015 1 12A5C6 WASHER 8 EA
016 1 14A5C101 LOCKWASHER 8 EA
018 1 MLH65457AG1 BRACKET FILTER TOP 1 EA
019 1 12597159 UBOLT 1 EA
021 1 MLH65468G1 PIPING FILTER TO MB 1 EA
023 1 R88770 GASKET 1 EA R.O.C.E.M
028 1 33941550 TUBING 0.38X065W 65 IN

PARTS LIST
FRAME OIL PUMP PIPING
H65408, REV. G
PARTS LIST
MLH65408G1 004 PIPING FRAME OIL H65408
Number Level
029 1 427A10S08 CONNECTOR FEMALE 2 EA
030 1 431A10S06 TEE UNION TUBE 1 EA
031 1 W149599AT2 CAP TUBE 1 EA
032 1 20DPG-OS-30 GAUGE DIFF PRESS 1 EA ....M
033 1 1R60971T7D CLOSURE 2 EA
034 1 ZTZM0015 BRACKET OIL GAUGE 1 EA
036 1 11A5C2 WASHER PLAIN 2 EA
037 1 426A10S12 CONNECTOR MALE 2 EA

PARTS LIST
ML66972G7 001 BOLTING FLANGE NONE
Number Level
1 R78164VX05014 STUD 4 EA
1 31A11C8 GASKET 1 EA R.O.C.E.M
1 38A4K7 NUT 8 EA
© 2013 DRESSER-RAND COMPANY ML66972G7

PARTS LIST
Number Level
1 R78164VX05012 STUD 4 EA
1 38A4K7 NUT 8 EA

PARTS LIST
1R88502B 001 KIT OIL FILTER./.%
Number Level
1 R88502BT1 FILTER OIL 1 EA
1 R88502BT2 ELEMENT FILTER OIL 1 EA
© 2013 DRESSER-RAND COMPANY 1R88502B

PARTS LIST
Number Level
1 R78164VX05013 STUD 4 EA
1 38A4K7 NUT 8 EA

PARTS LIST
PRIMING OIL PUMP COVER
H65411A
PARTS LIST
MLH65411AG1 002 COVER PRELUBE PUMP H65411A
Number Level
001 1 RCHM0001 COVER PRELUBE PUMP 1 EA
004 1 30A7S6 PLUG SOLID SQUARE HEAD 1 EA
© 2012 DRESSER-RAND COMPANY MLH65411AG1

PARTS LIST
OIL STRAINER HEADER
H65386
PARTS LIST
MLH65386G1 002 HEADER OIL STRAINER H65386
Number Level
001 1 MLW91652JG1 STRAINER OP SUCTION 1 EA
003 1 R78164VX05012 STUD 4 EA
004 1 38A4K7 NUT 4 EA
005 1 R86287 FOOT HEADER 1 EA
006 1 11A5C4 WASHER PLAIN 1 EA

PARTS LIST
LUBRICATION SYSTEM ASSEMBLY
QHHA0489
PARTS LIST
MLQHHA0489G1 001 LUBRICATION SYSTEM QHHA0489
Number Level
1 ZTZM0001 BRACKET CYL LUBE 1 EA
1 119A2A152 CAPSCREW 4 EA
001 1 QIHP0238-04E LUBRICATOR UNIT 1 EA
002 1 QJZP0038E PUMP LUBRICATOR 2 EA ....M
004 1 QQZP0432 MANIFOLD LUBRICATOR 1 EA
005 1 QKZP0002 GAUGE PRESSURE 1 EA
006 1 QLZP0001 FILTER INLINE 10M 1 EA .O..E.M
007 1 QSZP3063 BLOCK DIVIDER 1 EA
00 .2 QMZP0001 INDICATOR CYC PIN 4 EA
010 1 QOZP0001 SWITCH PROXIMITY 1 EA
011 1 1000189513 KIT SRVC ITEM/S 1 EA
012 1 QMZP0001 INDICATOR CYC PIN 1 EA
013,015 1 426A10S06 CONNECTOR MALE 7 EA
016 1 431A10S04 TEE UNION TUBE 2 EA
017 1 430A10S04 ELBOW UNION 1 EA
018 1 437A10S03 UNION 4 EA
020 1 QRZP0001 DISK ATMOSPHERIC INDTR 1 EA
© 2012 DRESSER-RAND COMPANY MLQHHA0489G1

PARTS LIST
WEIGHT CROSSHEAD BALANCE ASSEMBLY
W140338E
PARTS LIST
MLW140338EG7 001 WEIGHT XHD BAL W140338E
Number Level
001 1 H49944FT2 WEIGHT BAL 5.74# 1 EA
002 1 35A2J376E CAPSCREW 8 EA
© 2012 DRESSER-RAND COMPANY MLW140338EG7

PARTS LIST
7SHC401/02 001 SN: 7SHC401 MODEL: CYLINDER 15.00
Number Level
1 MLHIHA1571G2 CYLINDER 15.00 HOS 1 EA
1 MLH50037G6 ACCESS VALVE HOS 8 EA
1 MLH50042MG1 PISTON 15.0 &ROD 7HOSS 1 EA
1 MLH56039NG4 VALVE 67PF INLET 4 EA
1 MLH56040LG4 VALVE 67PF DISCH HOS 4 EA
1 MLH65498G3 YOKE 16.00 1 EA
1 MLLAHA0174G1 PACKING ECR COMPLETE 1 EA
1 MLMDHA1572G1 HEAD OUTER VVCP 1 EA
1 MLQBZA0001G75 LUBE SYS CYLINDER 1 EA
© 2012 DRESSER-RAND COMPANY 7SHC401

PARTS LIST
CYLINDER ASSEMBLY
HIHA1571, REV. 01
PARTS LIST
MLHIHA1571G2 003 CYLINDER 15.00 HOS HIHA1571
Number Level
1 VAHK1401 KIT GASKET 1 EA
1 1R60971T33C CLOSURE 2 EA
001 1 1HIHM1571 CYLINDER 15.00 1 EA
005 1 UAZM0003T2 ADAPTER QUILL 2 EA
006 1 143A7TT2 ELBOW 90 DEG ST 2 EA
007 1 W71484 COVER HAND HOLE 2 EA
008 1 W67095 GASKET HAND HOLE 2 EA R.O.C.E.M
010 1 11021953 PIPE PLUG 6 EA
011 1 R78164X08043R STUD 24 EA
012,015 1 38A4K10 NUT 88 EA
013 1 R78164X08041R STUD 32 EA
014 1 R78164X08049R STUD 16 EA
016 1 R78164X07064R STUD 4 EA
017 1 38A4K9 NUT 4 EA
018 1 REHM7502 COVER VALVE 8 EA
019 1 20A11KM445 ORING 8 EA R.O.C.E.M
020 1 11117074 KIT NAMEPLATE 1 EA
021 1 R85226 VALVE CHECK 2 EA ....M
© 2012 DRESSER-RAND COMPANY MLHIHA1571G2

PARTS LIST
VAHK1401 001 KIT GASKET NONE
Number Level
1 W67095 GASKET HAND HOLE 2 EA R.O.C.E.M
1 X1498T29U GASKET PKG CASE 1 EA R.O.C.E.M
1 20A11KM445 ORING 8 EA R.O.C.E.M
1 35A11C13 GASKET RING 2 EA R.O.C.E.M
© 2013 DRESSER-RAND COMPANY VAHK1401

PARTS LIST
VVCP ASSEMBLY
MDHA1572, REV. 01
PARTS LIST
MLMDHA1572G1 004 HEAD OUTER VVCP0'+$
Number Level
1 1TWZM0004A WRENCH LOCKING 1 EA
1 1000236113 COVER 15.0 VVCP OUTER HEAD 1 EA
001 1 MDHM1571 HEAD 15.0 VVCP OUTER 1 EA
003 1 R78164CX09057R STUD 12 EA
004 1 46A4K11 NUT HVY HEX 12 EA
005 .2 VBZP0001T433 ORING 2 EA R.O.C.E.M
006 .2 183A13SXRRT350 RING RETAINING 1 EA .O..E.M
007 .2 W127907BP1 WASHER RETAINER 2 EA
008 .2 211A11F163P SEAL 2 EA
009 .2 W127848 RING LANTERN 1 EA
010 1 MEHM0001P1 HOUSING VVCP 1 EA
011 1 TEVM0008D NUT ACME RETAINING 1 EA
012 1 TEVM0015H COVER RETAINING NUT 1 EA
013 1 1000227418 KEY ROUNDED END 1 EA
014 1 TWZM0003 WRENCH ACTUATING 1 EA
016 .2 ZZHM0002T2 PLUNGER 1 EA
017 .2 PP1022 SPRING 1 EA R.O.C.E.M
018 .2 ZZHM0002T1 HANDLE PLUNGER 1 EA
019 1 ZZHM0003 COVER VVCP ROD 1 EA
020 1 12617478 PISTON ROD VVCP ASSY 1 EA
021 1 KBHP1571 RING 11.75 VVCP 1 EA
023 1 ZZVM0006 COVER WINDOW 1 EA
© 2012 DRESSER-RAND COMPANY MLMDHA1572G1

PARTS LIST
VVCP ASSEMBLY
MDHA1572, REV. 01
PARTS LIST
Number Level
027 1 250A10X1610B FITTING GREASE 1 EA
028 1 X1010A NUT SPECIAL 8 EA
029 1 TAHM0071 STUD VVCP 8 EA
031 1 W149594 CLOSURE VENT 2 EA
033 .2 ZZZP0071 BEARING JOURNAL 1 EA .O..E.M
034 1 VAZM0007 COVER GASKET WINDOW 1 EA R.O.C.E.M
035 1 VBZP0001T458 ORING 1 EA R.O.C.E.M
038 1 1000258169 KIT PKG REBUILD VVCP 1 EA

PARTS LIST
PISTON & ROD ASSEMBLY
H50042M
PARTS LIST
MLH50042MG1 003 PISTON 15.0 &ROD 7HOSS H50042M
Number Level
001 1 IAUM1571 ROD PISTON 15.00 HOSS 1 EA
002 1 W84456B NUT PISTON HOS 1 EA ....M
004 1 X1010T13 NUT 1 EA
005 1 1JAHM1503 PISTON 15.00 1 EA ....M
006 1 KCHP1412 RING 15.00 PISTON 2 EA
007 1 R72004CP1 COLLAR FR END HOS 1 EA ....M
008 1 R72005P4 COLLAR OUT END HOS 1 EA ....M
© 2012 DRESSER-RAND COMPANY MLH50042MG1

PARTS LIST
ECR PACKING COMPLETE
LAHA0174
PARTS LIST
MLLAHA0174G1 001 PACKING ECR COMPLETE/$+$
Number Level
001 1 LAHP0171 CASE PISTON ROD PKG 1 EA
002 1 1000195356 RING SET RENEWAL 1 EA R.O.C.E.M
003 .2 R87096AVX436T46A RING PACKING 1 EA
004 .2 R87096BHX728XBT46 PACKING ECR RING 3 EA .O..E.M
005 .2 R87096VX728T46 RING PACKING 1 EA
006 1 X1498T29U GASKET PKG CASE 1 EA R.O.C.E.M
© 2012 DRESSER-RAND COMPANY MLLAHA0174G1

PARTS LIST
PACKING CASE REFERENCE DRAWING

SEE DRAWING FOR PART NUMBERS
PARTS LIST
67 PF INLET VALVE ASSEMBLY
H56039N
PARTS LIST
MLH56039NG4 001 VALVE 67PF INLET H56039N
Number Level
001 1 F36497N SEAT INLET VALVE 1 EA
002 1 F36498VT3 STOPPLATE INLET 1 EA
005 1 PP1428 SPRING 16 EA R.O.C.E.M
006 1 H56068D PLATE VALVE 1 EA R.O.C.E.M
007 1 121A2R202 SCREW SKT SHLDR 1 EA
© 2012 DRESSER-RAND COMPANY MLH56039NG4

PARTS LIST
67 PF DISCHARGE VALVE ASSEMBLY
H56040L
PARTS LIST
MLH56040LG4 001 VALVE 67PF DISCH HOS H56040L
Number Level
001 1 F36499M SEAT VALVE DISCH 1 EA
002 1 F36500NT3 STOPPLATE DISCH 1 EA ..C.E.M
© 2012 DRESSER-RAND COMPANY MLH56040LG4

PARTS LIST
VALVE ACCESSORIES
H50037, REV. A
PARTS LIST
MLH50037G6 001 ACCESS VALVE HOS H50037
Number Level
003 1 R70778P7 CRAB VALVE 1 EA ...E.M
004 1 30A11F0740X13 GASKET 1 EA R.O.C.E.M
005 1 112A2S23 SET SCREW HEX SKT 1 EA ...E.M

PARTS LIST
YOKE ASSEMBLY
H65498, REV. 02
PARTS LIST
MLH65498G3 005 YOKE 16.00 H65498
Number Level
001 1 F43320 DISTANCE PC 16.00 1 EA
002 1 MLR88766G1 COVER DISTANCE PC 2 EA
003 1 R88767 GASKET 16 DIST PCE 2 EA
005 1 R70754P6 TIEROD YOKE HOS 16 4 EA
009 1 R70691F OIL STUFFER 2.88ROD 1 EA
011 1 LEHP0002 DEFLECTOR PLATE OIL 1 EA
013 1 MLLEHA0626G1 WIPER STD HOSS 1 EA
016,020 1 W47886 ADAPTER 2 EA
017 1 33037417 VALVE CHECK LUBR 1 EA ....M
018 1 428A10S06 ELBOW MALE 3 EA
019,022 1 UHZP0001T24 FLEXIBLE HOSE .25 2 EA

PARTS LIST
THIS PAGE IS
INTENTIONALLY
LEFT BLANK
Report Date: 11 July 2011
PARTS LIST
MLLEHA0626G1 001 WIPER STD HOSS NONE
Number Level
1 LEHP0626 CASE PKG OIL WIPER 1 EA
.2 C3-CE9950-OHH15 RING SCRAPER (SET) 1 EA R.O.C.E.M
.2 C3-CE9951-OHH14 RING SEAL TFE (PAIR) 1 EA R.O.C.E.M
000 1 KEHK0626 KIT RNL WIPER RING 1 EA R.O.C.E.M
© 2011 DRESSER-RAND COMPANY MLLEHA0626G1

PARTS LIST

PARTS LIST
CYLINDER LUBRICATION SYSTEM
QBZA0001, REV. E
PARTS LIST
MLQBZA0001G75 002 LUBE SYS CYLINDER QBZA0001
Number Level
001 1 ZTZM0003 BRACKET DIV BLOCK 1 EA
008 1 33941519 TUBING 0.25X065W 120 IN
© 2012 DRESSER-RAND COMPANY MLQBZA0001G75

PARTS LIST
7SHC403/04 001 SN: 7SHC403 MODEL: CYLINDER 9.50
Number Level
1 MLHIHA0971G7 CYLINDER 9.50 1 EA
1 MLH49998HG2 PISTON 9.50 & ROD HOSS 1 EA
1 MLH50020G9 ACCESS VALVE HOS 8 EA
1 MLH54474VG15 VALVE PF60 INLET 4 EA
1 MLH54475LG21 VALVE PF60 DISCH 4 EA
1 MLH65498G3 YOKE 16.00 1 EA
1 MLLAHA0175G1 PACKING COMPLETE ECR 1 EA
1 MLMDHA0973G2 HEAD OUTER VVCP 1 EA
1 MLQBZA0001G41 LUBE SYS CYLINDER 1 EA
© 2012 DRESSER-RAND COMPANY 7SHC403

PARTS LIST
CYLINDER ASSEMBLY
HIHA0971, REV. 02
PARTS LIST
MLHIHA0971G7 002 CYLINDER 9.50 HIHA0971
Number Level
1 VAHK0901 KIT GASKET 1 EA
001 1 1HIHM0979 CYLINDER 9.50 1 EA
005 1 UAZM0003T2 ADAPTER QUILL 2 EA
007 1 W71484 COVER HAND HOLE 2 EA
008 1 W67095 GASKET HAND HOLE 2 EA R.O.C.E.M
010 1 11021953 PIPE PLUG 6 EA
011 1 R78164X07065R STUD 4 EA
012 1 38A4K9 NUT 4 EA
013 1 R78164CX09053R STUD 24 EA
014,017 1 46A4K11 NUT HVY HEX 88 EA
015 1 R78164CX09054R STUD 16 EA
016 1 R78164CX09045R STUD 32 EA
018 1 R72019A COVER VALVE 8 EA ...E.M
019 1 VBZP0001T438 ORING 8 EA R.O.C.E.M
020 1 R85226 VALVE CHECK 2 EA ....M
021 1 11117074 KIT NAMEPLATE 1 EA
© 2012 DRESSER-RAND COMPANY MLHIHA0971G7

PARTS LIST
VAHK0901 001 KIT GASKET NONE
Number Level
1 VBZP0001T438 ORING 8 EA R.O.C.E.M
© 2013 DRESSER-RAND COMPANY VAHK0901

PARTS LIST
VVCP OUTER HEAD
MDHA0973, REV. 1
PARTS LIST
Number Level
1 1TWZM0004A WRENCH LOCKING 1 EA
1 12633194 HEAD 9.50 VVCP OTR 1 EA
002 1 H32894T3 GASKET 1 EA R.O.C.E.M
003 1 R78164CX09053R STUD 12 EA
005 .2 VBZP0001T433 ORING 2 EA R.O.C.E.M
006 .2 183A13SXRRT350 RING RETAINING 1 EA .O..E.M
007 .2 W127907BP1 WASHER RETAINER 2 EA
008 .2 211A11F163P SEAL 2 EA
009 .2 W127848 RING LANTERN 1 EA
010 1 MEHM0001P1 HOUSING VVCP 1 EA
011 1 TEVM0008D NUT ACME RETAINING 1 EA
012 1 TEVM0015H COVER RETAINING NUT 1 EA
013 1 1000227418 KEY ROUNDED END 1 EA
014 1 TWZM0003 WRENCH ACTUATING 1 EA
016 .2 ZZHM0002T2 PLUNGER 1 EA
017 .2 PP1022 SPRING 1 EA R.O.C.E.M
018 .2 ZZHM0002T1 HANDLE PLUNGER 1 EA
019 1 ZZHM0003 COVER VVCP ROD 1 EA
020 1 12617445 PISTON ROD VVCP ASSY 1 EA
021 1 KBHP0004 RING 7.50 VVCP 1 EA
023 1 ZZVM0006 COVER WINDOW 1 EA

PARTS LIST
VVCP OUTER HEAD
MDHA0973, REV. 1
PARTS LIST
Number Level
027 1 250A10X1610B FITTING GREASE 1 EA
028 1 X1010A NUT SPECIAL 8 EA
029 1 TAHM0071 STUD VVCP 8 EA
030 1 183A13SXRRT750 RING RETAINING 1 EA .O..E.M
031 1 W149594 CLOSURE VENT 2 EA
032 1 VAZM0007 COVER GASKET WINDOW 1 EA R.O.C.E.M
033 .2 ZZZP0071 BEARING JOURNAL 1 EA .O..E.M
036 1 1000258169 KIT PKG REBUILD VVCP 1 EA

PARTS LIST
PISTON & ROD ASSEMBLY
H49998H
PARTS LIST
MLH49998HG2 001 PISTON 9.50 & ROD HOSS H49998H
Number Level
001 1 JAUM0971 PISTON 9.50 HOSS 1 EA ....M
002 1 IAUM0971 ROD PISTON 9.50 HOSS 1 EA
003 1 1R81224YT3 PISTON JAMNUT 1 EA ....M
004 1 X1010T13 NUT 1 EA
005 1 KCHP0616T1 RING 9.50 PISTON 3 EA R.O.C.E.M
© 2012 DRESSER-RAND COMPANY MLH49998HG2

PARTS LIST
PACKING ECR COMPLETE
LAHA0175
PARTS LIST
MLLAHA0175G1 001 PACKING COMPLETE ECR/$+$
Number Level
001 1 LAHP0172 CASE PISTON ROD PKG 1 EA
002 1 1000195357 RING SET RENEWAL 1 EA R.O.C.E.M
006 1 X1498T29U GASKET PKG CASE 1 EA R.O.C.E.M
© 2012 DRESSER-RAND COMPANY MLLAHA0175G1

PARTS LIST

PARTS LIST
PF60 INLET VALVE ASSEMBLY
H54474V
PARTS LIST
MLH54474VG15 001 VALVE PF60 INLET H54474V
Number Level
001 1 F35755LP1 SEAT INLET 60PF 1 EA ...E.M
002 1 F35756NT3 STOPPLATE 60PF INL 1 EA ..C.E.M
© 2012 DRESSER-RAND COMPANY MLH54474VG15

PARTS LIST
PF60 DISCHARGE VALVE ASSEMBLY
H54475L
PARTS LIST
MLH54475LG21 001 VALVE PF60 DISCH H54475L
Number Level
001 1 F35757JP1 SEAT DISCH 60PF 1 EA ...E.M
002 1 F35758LT2 STOPPLATE 60PF 1 EA ..C.E.M

PARTS LIST
ACCESS VALVE
H50020
PARTS LIST
MLH50020G9 001 ACCESS VALVE HOS H50020
Number Level
003 1 OAHM6006 CRAB VALVE 1 EA
004 1 30A11F0650X12 GASKET 1 EA R.O.C.E.M
005 1 112A2S23 SET SCREW HEX SKT 1 EA ...E.M

PARTS LIST
YOKE ASSEMBLY
H65498, REV. 02
PARTS LIST
MLH65498G3 005 YOKE 16.00 H65498
Number Level
001 1 F43320 DISTANCE PC 16.00 1 EA
002 1 MLR88766G1 COVER DISTANCE PC 2 EA
003 1 R88767 GASKET 16 DIST PCE 2 EA
005 1 R70754P6 TIEROD YOKE HOS 16 4 EA
009 1 R70691F OIL STUFFER 2.88ROD 1 EA
011 1 LEHP0002 DEFLECTOR PLATE OIL 1 EA
013 1 MLLEHA0626G1 WIPER STD HOSS 1 EA
016,020 1 W47886 ADAPTER 2 EA
017 1 33037417 VALVE CHECK LUBR 1 EA ....M
019,022 1 UHZP0001T24 FLEXIBLE HOSE .25 2 EA

PARTS LIST
THIS PAGE IS
INTENTIONALLY
LEFT BLANK
Report Date: 11 July 2011
PARTS LIST
MLLEHA0626G1 001 WIPER STD HOSS NONE
Number Level
1 LEHP0626 CASE PKG OIL WIPER 1 EA
.2 C3-CE9950-OHH15 RING SCRAPER (SET) 1 EA R.O.C.E.M
.2 C3-CE9951-OHH14 RING SEAL TFE (PAIR) 1 EA R.O.C.E.M
00 1 KEHK0626 KIT RNL WIPER RING 1 EA R.O.C.E.M
© 2011 DRESSER-RAND COMPANY MLLEHA0626G1

PARTS LIST

PARTS LIST
CYLINDER LUBRICATION SYSTEM
QBZA0001, REV. E
PARTS LIST
MLQBZA0001G41 002 LUBE SYS CYLINDER QBZA0001
Number Level
001 1 ZTZM0003 BRACKET DIV BLOCK 1 EA
008 1 33941519 TUBING 0.25X065W 120 IN
© 2012 DRESSER-RAND COMPANY MLQBZA0001G41

PARTS LIST
1000257729 002 KIT SHIP LOOSE (7SHF162)
Number Level
1 MLZBHA0005G3 KIT TOOL HOSS 1 EA
1 VAZK4002 GASKET KIT 1 EA
1 W106865 COOLER OIL 1 EA ....M
1 W82559 BREATHER FR RDS HOS 1 EA .O..E.M
© 2013 DRESSER-RAND COMPANY 1000257729

PARTS LIST
TOOL KIT
ZBHA0005, REV. O1
PARTS LIST
MLZBHA0005G3 001 KIT TOOL HOSS ZBHA0005
Number Level
1 7718A BOX TOOL DRI 1 EA
001 1 MLZBHA0006G1 SLEEVE ENTERING COML 1 EA
002 1 ZBHM0001 ADAPTER PISTON NUT 1 EA
003 1 12607685 WRENCH 4.25 OPEN 1 EA
© 2013 DRESSER-RAND COMPANY MLZBHA0005G3

PARTS LIST
ENTERING SLEEVE TOOL KIT
ZBHA0006, RE V. 01
PARTS LIST
MLZBHA0006G1 001 SLEEVE ENTERING COML ZBHA0006
Number Level
001 1 ZBHM0010T1 SLEEVE COLLAR 1 EA
002 1 ZBHM0010T2 SLEEVE PISTON ROD 1 EA
© 2013 DRESSER-RAND COMPANY MLZBHA0006G1

PARTS LIST
THIS PAGE IS
INTENTIONALLY
LEFT BLANK
PARTS LIST
VAZK4002 001 GASKET KIT NONE
Number Level
1 H65329 GASKET FR D E 1 EA R.O.C.E.M
1 H65345 GASKET FR OPE CVR 1 EA R.O.C.E.M
1 H65376 GASKET CVR PUMP END 1 EA R.O.C.E.M
1 H65377 GASKET FR TOP BAY 1 EA
1 H65378 GASKET FR TOP CVR ROD BAY 2 EA R.O.C.E.M
1 H65379 GASKET FR TOP CVR DR END 1 EA R.O.C.E.M
1 H65380 GASKET FR EXT SIDE CVR 8 EA R.O.C.E.M
1 R88770 GASKET 1 EA R.O.C.E.M
1 W73193A GASKET 2 EA R.O.C.E.M
1 W83586 GASKET 1 EA R.O.C.E.M
1 20A11CM279 ORING 4 EA R.O.C.E.M
© 2013 DRESSER-RAND COMPANY VAZK4002

PARTS LIST
1000263759 001 SPARES
Number Level
1 1000263883 SPARES START UP 7HOSS4 1 EA
1 1000263884 SPARES 2 YR 7HOSS4 1 EA
1 1000263885 SPARES 2 YR 15.00 CYL HOSS 1 EA
1 1000263886 SPARES 2 YR 9.50 CYL HOSS 1 EA
1 1000263887 SPARES START UP 15.00 CYLINDER 1 EA

HOSS
1 1000263888 SPARES START UP 9.50 CYLINDER 1 EA

HOSS

PARTS LIST
1000263883 001 SPARES START UP 7HOSS4
Number Level
.2 H65329 GASKET FR D E 1 EA R.O.C.E.M
.2 H65345 GASKET FR OPE CVR 1 EA R.O.C.E.M
.2 H65376 GASKET CVR PUMP END 1 EA R.O.C.E.M
.2 H65377 GASKET FR TOP BAY 1 EA
.2 H65378 GASKET FR TOP CVR ROD BAY 2 EA R.O.C.E.M
.2 H65379 GASKET FR TOP CVR DR END 1 EA R.O.C.E.M
.2 H65380 GASKET FR EXT SIDE CVR 8 EA R.O.C.E.M
.2 R88770 GASKET 1 EA R.O.C.E.M
.2 W73193A GASKET 2 EA R.O.C.E.M
.2 W83586 GASKET 1 EA R.O.C.E.M
.2 20A11CM279 ORING 4 EA R.O.C.E.M

PARTS LIST
1000263884 001 SPARES 2 YR 7HOSS4
Number Level
1 H65313 BUSHING CONNROD 8 EA .O..E.M
1 H65318 PIN CROSSHEAD 4 EA ...E.M
.2 H65329 GASKET FR D E 2 EA R.O.C.E.M
.2 H65345 GASKET FR OPE CVR 2 EA R.O.C.E.M
.2 H65376 GASKET CVR PUMP END 2 EA R.O.C.E.M
.2 H65377 GASKET FR TOP BAY 2 EA
.2 H65378 GASKET FR TOP CVR ROD BAY 4 EA R.O.C.E.M
.2 H65379 GASKET FR TOP CVR DR END 2 EA R.O.C.E.M
.2 H65380 GASKET FR EXT SIDE CVR 16 EA R.O.C.E.M
1 R88501 SHOE THRUST 2 EA .O..E.M
.2 R88770 GASKET 2 EA R.O.C.E.M
1 W118658P7 SEAL CRANKSHAFT 2 EA ..C.E.M
1 W31371P1 BUSHING OIL PUMP 2 EA .O..E.M
.2 W73193A GASKET 4 EA R.O.C.E.M
1 W82537 GAUGE OIL LEVEL 1 EA ....M
1 W82559 BREATHER FR RDS HOS 2 EA .O..E.M
1 W93317B VALVE PRESS CONTROL 1 EA ....M
1 1R88492 SHIM XHD SHOE 16 EA .O..E.M
1 12592416 BOX CRANKPIN 8 EA .O..E.M
.2 20A11CM279 ORING 8 EA R.O.C.E.M
1 20DPG-OS-30 GAUGE DIFF PRESS 1 EA ....M

PARTS LIST
1000263887 001 SPARES START UP 15.00 CYLINDER HOSS
Number Level
1 H56068D PLATE VALVE 8 EA R.O.C.E.M
1 KCHP1412 RING 15.00 PISTON 3 EA
1 PP1428 SPRING 64 EA R.O.C.E.M
1 1000195356 RING SET RENEWAL 1 EA R.O.C.E.M
1 30A11F0740X13 GASKET 8 EA R.O.C.E.M

PARTS LIST
1000263885 001 SPARES 2 YR 15.00 CYL HOSS
Number Level
1 IAUM1571 ROD PISTON 15.00 HOSS 1 EA
1 KBHP1571 RING 11.75 VVCP 2 EA
1 KCHP1412 RING 15.00 PISTON 6 EA
1 KEHK0626 KIT RNL WIPER RING 1 EA R.O.C.E.M
1 MLH56039NG4 VALVE 67PF INLET 4 EA
1 MLH56040LG4 VALVE 67PF DISCH HOS 4 EA
1 R85226 VALVE CHECK 2 EA ....M
1 R88767 GASKET 16 DIST PCE 4 EA
1 1JAHM1503 PISTON 15.00 1 EA ....M
1 183A13SXRRT350 RING RETAINING 1 EA .O..E.M
1 25A13C98 ROLLPIN 32 EA R.O.C.E.M
1 33037417 VALVE CHECK LUBR 1 EA ....M

PARTS LIST
KEHK0626 001 KIT RNL WIPER RING NONE
Number Level
1 C3-CE9950-OHH15 RING SCRAPER (SET) 1 EA R.O.C.E.M
1 C3-CE9951-OHH14 RING SEAL TFE (PAIR) 1 EA R.O.C.E.M
© 2013 DRESSER-RAND COMPANY KEHK0626

PARTS LIST
67 PF INLET VALVE ASSEMBLY
H56039N
PARTS LIST
MLH56039NG4 001 VALVE 67PF INLET H56039N
Number Level
001 1 F36497N SEAT INLET VALVE 1 EA
002 1 F36498VT3 STOPPLATE INLET 1 EA
© 2013 DRESSER-RAND COMPANY MLH56039NG4

PARTS LIST
67 PF DISCHARGE VALVE ASSEMBLY
H56040L
PARTS LIST
MLH56040LG4 001 VALVE 67PF DISCH HOS H56040L
Number Level
001 1 F36499M SEAT VALVE DISCH 1 EA
002 1 F36500NT3 STOPPLATE DISCH 1 EA ..C.E.M

PARTS LIST
1000195356 001 RING SET RENEWAL
Number Level
1 R87096AVX436T46A RING PACKING 1 EA
1 R87096BHX28XBT46 PACKING ECR RING 3 EA .O..E.M
1 R87096VX728T46 RING PACKING 1 EA

PARTS LIST
1000263888 001 SPARES START UP 9.50 CYLINDER HOSS
Number Level
1 H32894T3 GASKET 1 EA R.O.C.E.M
1 KCHP0616T1 RING 9.50 PISTON 3 EA R.O.C.E.M

PARTS LIST
Number Level

PARTS LIST
1000263886 001 SPARES 2 YR 9.50 CYL HOSS
Number Level
1 H32894T3 GASKET 2 EA R.O.C.E.M
1 IAUM0971 ROD PISTON 9.50 HOSS 1 EA
1 JAUM0971 PISTON 9.50 HOSS 1 EA ....M
1 KBHP0004 RING 7.50 VVCP 2 EA
1 KCHP0616T1 RING 9.50 PISTON 6 EA R.O.C.E.M
1 KEHK0626 KIT RNL WIPER RING 1 EA R.O.C.E.M
1 MLH54474VG15 VALVE PF60 INLET 4 EA
1 MLH54475LG21 VALVE PF60 DISCH 4 EA
1 R85226 VALVE CHECK 2 EA ....M
1 R88767 GASKET 16 DIST PCE 4 EA
1 183A13SXRRT350 RING RETAINING 1 EA .O..E.M
1 25A13C98 ROLLPIN 32 EA R.O.C.E.M
1 33037417 VALVE CHECK LUBR 1 EA ....M

PARTS LIST
KEHK0626 001 KIT RNL WIPER RING NONE
Number Level
1 C3-CE9950-OHH15 RING SCRAPER (SET) 1 EA R.O.C.E.M
1 C3-CE9951-OHH14 RING SEAL TFE (PAIR) 1 EA R.O.C.E.M
© 2013 DRESSER-RAND COMPANY KEHK0626

PARTS LIST
PF60 INLET VALVE ASSEMBLY
H54474V
PARTS LIST
MLH54474VG15 001 VALVE PF60 INLET H54474V
Number Level
001 1 F35755LP1 SEAT INLET 60PF 1 EA ...E.M
002 1 F35756NT3 STOPPLATE 60PF INL 1 EA ..C.E.M
© 2013 DRESSER-RAND COMPANY MLH54474VG15

PARTS LIST
PF60 DISCHARGE VALVE ASSEMBLY
H54475L
PARTS LIST
MLH54475LG21 001 VALVE PF60 DISCH H54475L
Number Level
001 1 F35757JP1 SEAT DISCH 60PF 1 EA ...E.M
002 1 F35758LT2 STOPPLATE 60PF 1 EA ..C.E.M

PARTS LIST
THIS PAGE IS
INTENTIONALLY
LEFT BLANK
PARTS LIST
Number Level

NAO Parts Center CLIENT PDVSA Rec. Spares
Paul Clark Drive LOCATION QUOTE # 215321
Olean, NY 14760-0560 PROJECT # 121955 JAN 17/2013
Fax: (716) 376-2833 ORACLE #90032109
S/N 7SHF162
Contact: Cheryl Dodge MODEL 7HOSS4
Phone: (716) 375-5041
Line No. Part Number Part Description Qty Per Unit Comments
7HOSS4 FRAME (7SHF162)

1 R88501 SHOE THRUST 2
2 12592416 BOX CRANKPIN 4
3 W82537 GAUGE OIL LEVEL 1
4 W82559 BREATHER FR RDS HOS 1
5 H65313 BUSHING CONNROD 4
6 R86223A BOLT CONNROD 16
7 12592416 BOX CRANKPIN 4
8 H65318 PIN CROSSHEAD 4
9 H65317 SHOE CROSSHEAD 8
10 1R88492 SHIM XHD SHOE 32
11 MLH65341G1 PUMP OIL 4 THROW 1
12 QJZP0038E PUMP LUBRICATOR 2
13 QLZP0001 FILTER INLINE 10M 1
14 QMZP0001 INDICATOR CYC PIN 1
15 R88502BT2 ELEMENT FILTER OIL 1
15.0 IN CYLINDER (7SHC401/2) (X2)

16 20A11KM445 ORING 8
17 R85226 VALVE CHECK 1
18 W139566 GASKET 1
19 KBHP1571 RING 11.75 VVCP 1
20 IAUM1571 ROD PISTON 15.00 HOSS 1
21 1JAHM1503 PISTON 15.00 1
22 KCHP1412 RING 15.00 PISTON 2
23 1000195356 RING SET RENEWAL 1
24 X1498T29U GASKET PKG CASE 1
25 MLH56039NG4 VALVE 67PF INLET 4
26 MLH56040LG4 VALVE 67PF DISCH HOS 4
27 25A13C98 ROLLPIN 16
29 PP1428 SPRING 128
30 H56068D PLATE VALVE 8
31 30A11F0740X13 GASKET 8
32 R88767 GASKET 16 DIST PCE 2
33 KEHK0626 KIT RNL WIPER RING 1
34 33037417 VALVE CHECK LUBR 1
9.5 IN CYLINDER (7SHC403/4) (X2)

35 W67095 GASKET ! HAND COVER HOLE 2
36 VBZP0001T438 ORING 8
37 R85226 VALVE CHECK 2
38 H32894T3 GASKET 1
39 KBHP0004 RING 7.50 VVCP 1
40 JAUM0971 PISTON 9.50 HOSS 1
41 IAUM0971 ROD PISTON 9.50 HOSS 1
42 KCHP0616T1 RING 9.50 PISTON 3
43 1000195357 RING SET RENEWAL 1
44 X1498T29U GASKET PKG CASE 1
45 MLH54474VG15 VALVE PF60 INLET 4
46 MLH54475LG21 VALVE PF60 DISCH 4
48 PP1089 SPRING 64
49 H54460D PLATE VALVE 8
50 30A11F0650X12 GASKET 8
51 R88767 GASKET 16 DIST PCE 2
52 KEHK0626 KIT RNL WIPER RING 1
53 33037417 VALVE CHECK LUBR 1
Separable Assembly - Data Pack
Frame Serial # 7SHF162

Client Order # 90032109 Frame Inspection # C24108
(include DRI Serial # if applicable) DRI:
Frame Model HOSS Stroke Length 7 # of Throws 4

Clock # Date
Verify frame and caps are fit complete with proper stamping, painted and checked for
1 1709 10/9/12
cleanliness.
All oil passages have been checked for cleanliness; oil header checked for loose
2 10496 10/9/12
debris, all debris has been removed
Clean, install, and swedge riser tubes; wash header and spray with light oil after tubes
3 1766 10/9/12
are installed; re-inspect oil header for cleanliness
4 Install frame nameplate 10496 10/30/12
5 Verify tie bar spacer fit dimensions are stamped on frame (HOS,HOSS,BOS & DVIP) 11277 10/9/12
Crankshaft is inspected, oil holes are clean. Crankshaft inspection record is attached
6 2387 10/8/12
to datapack
7 Crankshaft dowel and counter weights fitup and installed 1709 10/9/12
Clock # Date
8 Record crank pin diametrical clearance
Crankshaft
Stretch conn rod; verify oil holes Record stretched crank pin
Calculated
are clean and fit up (transfer clock conn rod bearing diameter per
clearance
# from sub-assembly record) diameter crankshaft
record
Throw #1 2.387 8.2590 8.2495 0.0095 2387 10/8/12

Throw #2 2.387 8.2580 8.2495 0.0085 2387 10/8/12
Throw #3 2.387 8.2585 8.2490 0.0095 2387 10/8/12
Throw #4 2.387 8.2590 8.2495 0.0095 2387 10/8/12
Throw #5 0.0000
Throw #6 0.0000
Clock # Date
9 Record connecting rod weight and crank web side clearances
VIP/HOSS/BOS
Record conn rod Conn Rod
Visual check for
weight Serial #
no interference
Throw #1 230.4 127 OK 2387 10/8/12

Throw #2 229.1 138 OK 2387 10/8/12
Throw #3 229.4 129 OK 2387 10/8/12
Throw #4 229.1 145 OK 2387 10/8/12
Throw #5
Throw #6
QAF 262 - Rev.19 - Page 1 of 10 Rer

Clock # Date
Bearing inside diameters are oiled with bearing break in oil (i.e. STP) and
10 1766 10/9/12
crankshaft is installed
Clock # Date
11 Record connecting rod and crosshead to pin clearances
HOSS/BOS side HOS side
clearance, clearance,
checked checked between
Conn rod small Crosshead pin
Calculated between conn conn rod and
end I.D. as marked O.D. as marked
clearance rod bushing crankshaft web
on rod on pin
and crosshead with feelers or
with indicator calculated with
bump check inspection record
Throw #1 5.014 5.0065 0.0075 0.0155 N/A 2387 10/8/12
Throw #2 5.015 5.0065 0.0085 0.0160 2387 10/8/12
Throw #3 5.014 5.0065 0.0075 0.0150 2387 10/8/12
Throw #4 5.015 5.0065 0.0085 0.0155 2387 10/8/12
Throw #5 0.0000
Throw #6 0.0000
Clock # Date
12 Record main bearing clearances - checked with "stacked" feeler gauges or plastigage
1 Top 0.008 7119/1766 10/9/12
2 Top 0.008 7119/1766 10/9/12
3 Top 0.009 7119/1766 10/9/12
4 Top 0.008 7119/1766 10/9/12
5 Top
6 Top
Clock # Date
13 Record thrust by bump check - with indicator 0.025 7119/1766 10/9/12
Clock # Date
Record tie rod spacer final fit (HOS, HOSS, BOS, DVIP) within .001" of stamped dimension; verify
14
fit with top covers and stamp alignment mark across frame and spacer to finalize location
Throw #1 16.2500 11277 10/9/12
Throw #2 16.2500 11277 10/9/12
Throw #3 16.2500 11277 10/9/12
Throw #4 16.2500 11277 10/9/12
Throw #5
Throw #6

Record balance requirement (lbs.) -
15 Crosshead balancing process from frame lead sheet
Throw # 1 - Pump 2 3 4 5 6 - Drive
Conn Rod
Assembly
230.4 229.1 229.4 229.1 0.0 0.0
Piston, Rod,
Rings, Jamnut
223.0 225.9 223.2 225.9
Crosshead
Assembly
156.7 156.3 155.8 156.3
Balance Weights
Other
(i.e. Capscrews)
1.0
Crosshead Pin
and Pin Balance
Stub Shaft
VIP
Only
Jamnut
Washer
Tweak weights Add Tweak Weights

No Tweak Weights
Add Tweak Weights
No Tweak Weights No Tweak Weights No Tweak Weights
needed? Required Required Required Required
Min. tweak
weight package
1.2 0.0 1.9 0.0 0.0 0.0
Max. tweak
weight package
1.2 0.0 1.9 0.0 0.0 0.0
Tweak weight
used
1.680
Total 610.1 611.3 611.1 611.3 0.0 0.0
Clock # 11279 11279 11279 11279

Clock # Date
16 Record crosshead serial number and pin bore to pin clearance
Crosshead Pin Crosshead Pin
Crosshead CMM Crosshead Crosshead to
Bore I.D Pump Bore I.D Drive
number pin O.D. Pin clearance
End End
Throw #1 90.12 5.0065 5.0090 5.0090 0.0025 2387 10/8/12
Throw #2 78.12 5.0065 5.0090 5.0090 0.0025 2387 10/8/12
Throw #3 84.12 5.0065 5.0090 5.0090 0.0025 2387 10/8/12
Throw #4 76.12 5.0065 5.0090 5.0090 0.0025 2387 10/8/12
Throw #5 0.0000 0.0000
Throw #6 0.0000 0.0000
Clock # Date
Install crossheads after verifying that all oil holes are clean and fit up; after installation
17 11279 10/9/12
rotate crankshaft to make sure there is smooth operation and no interference
Install oil pump and set proper coupling clearance per instruction manual (indicate
18 11279 10/9/12
centering of pump shaft on HOSS)
Crankshaft oil slinger is installed properly per instruction manual, gap is even and
19 1709 10/11/12
checked for fit
20 Drive end cover is installed with top surface flush and is drilled and doweled 11277 10/16/12
21 Side mounted oil piping and filter are clean, fitup and installed 8234 10/10/12

Clock # Date
Record compressor cylinder and piston dimensions; record piston and rider ring clearance -
22
verifying clearances against cylinder instructions in the cylinder datapack
Piston diameter Diameter over
Bore diameter as Piston to bore (A) Piston to bore
with rings - wired tight
stamped clearance top clearance bottom
micrometer with micrometer
Throw # 1 9.5010 9.4150 9.4690 0.0590 0.0270 11279 10/16/12

Throw # 2 15.0010 14.8890 14.9530 0.0800 0.0320 11279 10/16/12
Throw # 3 9.5020 9.4180 9.4720 0.0570 0.0270 2105 10/16/12
Throw # 4 15.0005 14.8870 14.9540 0.0800 0.0335 11277 10/17/12
Throw # 5 0.0000 0.0000
Throw # 6 0.0000 0.0000
Clock # Date
23 Piston and rider ring clearances
(D) OD of piston
to piston ring (E) Ring side
(A) Piston to
(C) Rider band to pushed into clearance -
bore clearance
top of bore groove measured with
bottom
measured with feeler gauges
depth mic
Throw # 1 0.0270 0.0320 N/A 0.012 11279 10/16/12
Throw # 2 0.0320 0.0480 0.012 11279 10/16/12
Throw # 3 0.0270 0.0300 0.012 2105 10/16/12
Throw # 4 0.0335 0.0465 0.013 11277 10/16/12
Throw # 5 0.0000 0.0000
Throw # 6 0.0000 0.0000
Clock # Date
24 Verify cylinder bore is clean, lube bore and stab piston & rod assembly
Cylinder data
pack released
Serial #
from supervisor
(QAF-339)
Throw #1 7SHC403 10496 11277 10/18/12
Throw #2 7SHC401 10496 10496 10/30/12
Throw #3 7SHC404 10496 2105 10/16/12
Throw #4 7SHC402 10496 11277 10/17/12
Throw #5
Throw #6
Clock # Date
25 Hang cylinders in accordance with lead sheet
Throw #1 11277 10/18/12
Throw #2 8682 10/19/12
Throw #3 11277 10/17/12
Throw #4 8682 10/19/12
Throw #5
Throw #6

Clock # Date
26 Tighten piston rod jam nuts
Required Degree
Throw # 1 15 112277 10/18/12
Throw # 2 15 8682 10/18/12
Throw # 3 15 11277 10/17/12
Throw # 4 15 8682 10/18/12
Throw # 5
Throw # 6
Clock # Date
27 Record Compressor piston end clearances
Frame end - set with feeler
Outer end - measure with
gauges, measure with solder
digital depth micrometer and
and micrometers - cycle (3) X
account for gasket
before measuring
Throw # 1 0.066 0.075 11277/11279 10/17/12
Throw # 2 0.066 0.103 8177/8682 10/19/12
Throw # 3 0.060 0.079 11277/11279 10/16/12
Throw # 4 0.072 0.102 8177/8682 10/19/12
Throw # 5
Throw # 6
Clock # Date
28 Pressure packing verified as centered on rod - visual check - torqued per manual
Throw # 1 11279 10/17/12
Throw # 2 8682 10/24/12
Throw # 3 11277 10/16/12
Throw # 4 8682 10/24/12
Throw # 5
Throw # 6
Clock # Date
29 Stuffer Plate has been centered and torqued per assembly manual; deflector installed
Throw # 1 11279 10/17/12
Throw # 2 8682 10/24/12
Throw # 3 11277 10/16/12
Throw # 4 8682 10/24/12
Throw # 5
Throw # 6
Clock # Date
30 Record crosshead running clearance with feeler gages
Top - Frame End Top - Outer End Bottom
Throw # 1 0.016 0.017 0.0000 11279 10/17/12
Throw # 2 0.017 0.018 0.0000 8682 10/24/12
Throw # 3 0.017 0.018 0.0000 11279 10/16/12
Throw # 4 0.017 0.016 0.0000 8682 10/24/12
Throw # 5
Throw # 6

Clock # Date
31 Measure rod runout with digital or dial indicator
Vertical Horizontal
Throw # 1 -0.0015 -0.0005 8682 10/24/12
Throw # 2 -0.0030 0.0005 8682 10/24/12
Throw # 3 -0.0015 -0.0005 11279 10/16/12
Throw # 4 -0.0030 -0.0010 8682 10/24/12
Throw # 5
Throw # 6
Clock # Date
All critical fasteners are checked for tightness and are torqued and marked. Critical
32 fasteners include test bed bolting, spacer tie rods, conn rod bolts, crosshead pin caps, 2105 10/29/12
main bearing cap bolts, crosshead jamnut, and cylinder train bolting.
Weigh the fully assembled compressor while moving to the test bed,
33 29500.000 10844 11/5/12
record value
For all VVCP units, leave VVCP rods partially retracted before bolting to the head.
34 2105 10/29/12
Verify VVCP rods are greased
35 Fill Crank Case with Oil 2105 10/29/12
Flush Unit (See Note 3 below) - Open flush header on all HOSS models and all 6 throw
36 2105 10/29/12
HOS models
37 Torque hub and coupling 7207 10/29/12
38 Fill cylinder lubricator reservoir to proper level 10812 10/19/12
Prime each lubricator pump. Pumps are adjusted to full open for entire test. Verify lube
39 10812 10/19/12
to cylinder and to packing case
* Do Not exceed test RPM (from lead sheet) for any Run Test interval
Run Test RPM
Five Minute Ten Minute Twenty Minute Test Run
HOS /
HOSS 600 750 750
VIP-A 900 1200 1500
VIP-B 600 800 1000 See lead sheet for test
RPM and duration of
VIP-C 600 800 1000 final run
VIP-D 600 800 1000

BOS 500 600 700
Notes:
1. Turn on oil cooler at 160 deg. F
2. Adjust oil relief valve to maintain 55-psi min. oil pressure
3. Refer to D-R standard 32,950-02 for run test procedure

Initial 5 Minute Test Run
Start 9:42 Stop 9:47 See Table for RPM Page 5.
RPM 600 Oil Pressure 64 Oil Temp Start 85 Oil Temp End 90
Main Bearing Temperature Rod Bearing Temperature Crosshead Temperature
1 104 110 103
2 109 109 103
3 110 112 102
4 106 110 102
5
6
Intermediate 10 Minute Test Run

1 119 126 116
2 123 127 118
3 126 126 117
4 122 125 116
5
6
Intermediate 20 Minute Test Run

1 133 143 135
2 138 142 134
3 139 142 135
4 139 142 132
5
6
Test Run - Per frame lead sheet

1 155 158 145
2 157 162 146
3 159 158 145
4 158 160 144
5
6
Clock # Date
During Run Test
40 During hour or four hour test, drive end oil seal has been checked for leakage 2105 10/30/12
41 Verify pump cover and all oil piping does not leak 2105 10/30/12
42 There were no vibrations or knocking during testing 2105 10/30/12
43 The lubricator pump works with no leaks and all cycle pin indicators are functioning 2105 10/30/12
44 The oil scraper glands work, with no excessive leakage 2105 10/30/12
45 Frame covers have been checked for leakage 2105 10/30/12
Test Performed by: 2105/7207 Date: 10-30-12
Test Witnessed by: Brent Hoban Date: 10-30-12
Company: Date:

Clock # Date
Post Run Test
46 Ensure relief valve jamnut is tight 2105 10/30/12
Pull #1 main bearing cap and check bearing and crankshaft (except VIP-C, Inspect rod
47 2105/10496 10/30/12
bearings), take photos
48 Record thrust by bump check - with indicator 0.026 2105 10/30/12
49 Oil pump coupling is checked for clearance 2105 10/30/12
50 Frame tie bars are flush with frame top 8803 10/30/12
51 All cylinder bores have been visually checked for proper lubrication and are clean. 2105 10/30/12
52 All fasteners have been rechecked for torque marks, tab locks and safety wiring 8803 10/30/12
53 Crankcase has been drained and inspected for any signs of metal debris or distress 8803 10/30/12
54 Bottom of frame has been wiped clean - no debris left in frame 8803 10/30/12
Shipping category has been verified and all cylinders and frame are prepared
55 8803 10/30/12
accordingly
56 All closures have been installed (use steel closures only) 8803 10/30/12
57 All openings in cylinders and frames are plugged - bull plugs only 8803 10/30/12
58 All tube fittings have been gauged for being swedged correctly and for being tight 8803 10/30/12

Clock # Date
Auditor Check List
1 Inside of frame is clean 8803 10/30/12
2 Any cosmetic fitting, grinding, or filling is complete 8803 10/30/12
3 Lead sheet ECN level is correct 10844 11/5/12
4 All quality documents are complete and signed off, unless it is identified with N/A 10844 11/5/12
5 Crankshaft inspection record is attached 8803 10/30/12
6 Frame inspection serial number is recorded 10496 10/30/12
7 Namesplates are correct 10844 11/5/12
8 Frame stamping is complete 8803 10/30/12
9 Suction and discharge port closures are in place 8803 10/30/12
10 All holes are plugged 8803 10/30/12
11 Balance requirements are verified 8803 10/30/12
12 Torque marks are visually checked 8803 10/30/12
13 Packing case is installed correctly 8803 10/30/12
14 All tubing is tied properly and not interfering with the piston rod 8803 10/30/12
15 Outerhead has cylinder serial number stamped on it 8803 10/30/12
16 All heat numbers are recorded on the QAF-387 8803 10/30/12

Audit Report
Audit Team:
QC:
SBU / Eng:
Supervison:
Resp. Done By
Findings:
(Dept) (Clock #)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Finding Sign-off: Date

QC:
SBU / Eng:
Supervison:
Note: Compressor is authorized for final preservation and shipment after findings are signed off complete.

PG-581-B
DEC. 1991
SUB-MANUFACTURER'S EQUIPMENT
The instructions and replacement parts lists for sub-manufacturer supplied

equipment are located in this section. The content of these instructions and parts
lists are the responsibility of the particular sub-manufacturer. Prices that may be
given in the literature are those of the manufacturer and not those of Dresser-Rand
Company; no assurance can be given that these prices were current at the time this
Service Manual was issued.
UNIMAZE SMALL FILTERS
UNIMAZE ®
filters and filter silencers
The elements are interchangeable

Wing Nut Stem
in each model size to meet
filtering requirements of different
Top environment where equipments
may operate. See performance
chart for ratings of each. (See insert)
Features
Element • Simplified construction with
four basic components.
• Three easily interchangeable
filter elements.
• Nine standard MPT sizes
from 3/4” to 4”.
• Directly mounted on air
intake.
• Operation in temperature
range: -65° to 250°F.
• No sealant required on pipe
connection.
Base Tray Gasket • Lightweight and durable
components.
• No sharp edges.
• Optional weatherhood
protection.
Base Connector • Satisfactory sound attenuation
on silencer models.
Unimaze Small Filters and Hardware includes wing nut,

Filter Silencers have been stem, and gasket.
designed and engineered for air
intake of all small internal The base connector is glass
combustion engines, air reinforced engineered plastic.
compressors, and blowers with It combines strength, stability,
rated air flows to 450 CFM. and chemical resistance, with
distortion resistance and
aesthetic appeal. The glass
Filter Design reinforced plastic forms a
Unimaze Small Filters include naturally tight bond to metal to
just four component parts (1) eliminate air leakage.
element, (2) base connector, (3) (cont. on page 3)
top or optional weatherhood, Three filter elements are available:
and (4) base tray or body oil wetted wire mesh, synthetic
assembly. with wrap around prefilter, and
resin impregnated paper media.
Unimaze Filter
Applications
NB Wire Mesh Media
Silencers
Unimaze Small Filters are available
Where filtration of dirt particles
in Filter-Silencer models. They
10 micron or larger is required.
include a silencing chamber
The viscous impingement
which attenuates in the frequency
principle provides up to 94%
arrestment efficiency on harmful
dirt particles 10 micron and
larger. Crimped cylindrical-
shaped wire mesh element
permits greater filter surface
resulting in minimal pressure efficiency using SAC fine dust
drop. The elements are test. The element can be cleaned
reusable if cleaned properly by washing and reused.
and regularly.
UD Low Profile Filter
DA Synthetic Media Where maximum dirt holding
Where high efficiency filtration capacity and a high degree of
filtration of extremely fine dirt range of 250 to 8000 hertz per
particles is required; but where second. An expansion chamber
filter space is limited. Also for attenuates low frequency noise
where low initial air flow re- and an acoustical absorptive
striction is desired. Low pro- pad and baffles reduce high
frequency sound emissions.
Optional Weatherhoods
All Unimaze Small Filter and
Filter-Silencer models can be
supplied with attractive,
lightweight durable plastic
and long life at low pressure weatherhoods.
drop is required. Performance
is better than 98% efficiency on
particles of 3 micron mean
diameter, over 99% efficiency
on 5 micron mean particles, and
virtually 100% efficiency on 10 file design eliminated need to
micron particles and larger. The sacrifice filter capacity due to
polyester media element comes cramped installation envelope.
with a wrap around Efficiency, initial pressure loss
prefilter providing extended identical to DM Dry Paper
service life. Media. For better protection,
elements with foam safety
DM Dry Paper Media media are also available.
Where a high degree of filtration
of extremely fine dirt particles
is required. Standard laboratory
tests indicate better than 99.3%
UNIMAZE filters and filter silencers
SERVICING
NB Wire Mesh Media DA Synthetic Media DM Dry Paper Media
Remove hood top and lift out DA Filters must be cleaned at Dry Filters can be easily field
element. Since element is oil regular intervals. Filter elements serviced since accumulated
wetted, they should be cleaned should be replaced if ruptured or dirt can be removed by tapping
in any commercial cleaning torn. When the outside surface the element against the hand.
solution such as Oakite and of the element appears to be Implant, clean by: (1) directing
water. Dry thoroughly and evenly coated with dirt, it should compressed air up and down
immerse in SAE 30 engine oil. be cleaned as follows. Remove the pleats on the element
Drain off excess oil and wing nut and lift off hood or top; “clean” side (opposite the normal
reassemble. DO NOT CLEAN remove wrap-around prefilter operating air flow direction) at
FILTER ELEMENT IN GASOLINE element and replace or clean nozzle pressure no greater than
due to possible explosion on the by washing in water; lift out the 30 psi; or (2) use garden hose
receiver of a compressor. main element; shake or blow to direct clean, warm water (70°
off heavy dirt accumulations; if to 100°F) up and down side of
required, wash main element element at pressure no greater
in cold or warm water (a mild than 30 psi; or (3) wash in a mild
detergent solution will assist in detergent solution. Rinse and
cleaning); rinse and allow allow element to dry. Do not
element to dry; reassemble use other cleaning fluids. When
using new or cleaned wrap washing fails to restore element,
around prefilter element. it should be replaced.
ISO 9001:2000 & AS9100 Certified
115 East Steels Corners Road

Stow, OH 44224
330-928-4100
www.fallsfti.com
Falls Filtration Technologies reserves the right to change any
model or specification at any time without notice.
UNIMAZE performance data
UNIMAZE filter selection and parts list
P-95033N
Installation Instructions for Pressure and Vacuum Revised 07-99
Section 05
2 and 2-1/2 in. (51 and 64 mm) Dial MURPHYGAGE® (00-02-0162)
and SWICHGAGE® Instruments. 20, 25, A20, A25 Series

Please read the following instructions before installing. A visual inspection of this product for damage during shipping is recommended.
GENERAL INFORMATION
Typical Mounting Dimensions

20 Series shown A
WARNING Low Pressure
Port (DP Series)
Mounting Hole
B D
BEFORE BEGINNING INSTALLATION OF THIS MURPHY PRODUCT 1/8-27 NPTM Mounting
Pressure Port
✔ Disconnect all electrical power to the machine. Clamp
✔ Make sure the machine cannot operate during installation.
✔ Follow all safety warnings of the machine manufacturer.
✔ Read and follow all installation instructions. See Note
C
Description 20 Series A20 Series 25 Series A25 Series

The 2 and 2-1/2 in. (51 and 64 mm) dial size MURPHYGAGE® and SWICHGAGE® A 2-7/32 (56) 2-9/64 (54) 2-1/8 (54) 1-51/64 (46)
instruments are diaphragm-actuated, pressure or vacuum gages with a 1/8-27 NPTM B 2-15/64 (57) 2-1/4 (57) 3-1/8 (79) 2-29/32 (74)
pressure port connection (2 pressure ports for differential pressure models).
Models with face-adjustable contact(s) are rated for 2 A @ 30 V (pilot duty). If the C 1-5/16 (33) 1-27/64 (36) 1-3/8 (35) 1-27/64 (36)
gage case is steel (20P, 25P, 20DP, 25DP etc.) the ground path for the contact circuit D 2-1/16 (53) 2-1/16 (53) 2-11/16 (68) 2-11/16 (68)
is through the case. Therefore, the case must be installed in the ground plane of the
electrical power supply. NOTES: 20/25 Series: 18 AWG pigtails. A20/A25 series: #4/#6
screws. The dimensions above are in inches and (millimeters).
If the case is polycarbonate (A20P, A20DP, A25P, A25DP etc.) the ground path
is isolated and is made through the “C” or “P” terminals on the back of the gage Panel Mounting
case (“C” for A20 models; “P” for A25 models). All models can be installed in a panel from 0.032 to 0.250 in. (1 to 6 mm) thick.
Models 20PE, 25PE, A20PE, A25PE etc. have a snap-acting switch instead of Remove the mounting bracket and insert the gage from the front side of the panel.
the face adjustable pointer type contact. Electrical rating is 3 A @ 30 VDC, 4 A Replace bracket and secure it. Do NOT overtighten. (See Figure 2).
@ 125 VAC. Reset differential for the switch is approximately 10% of the scale.
NOTE: Select a scale so your normal operating pressure is in the upper middle of the scale.
Connecting the Pressure Port
CAUTION: Certain dangers to human safety and to equipment may occur 1. Pressure tubing is generally not provided. Use of good quality flexible pressure
if some equipment is stopped without pre-warning. It is recommended tubing/hose and fittings is strongly suggested. Use at least 3/16 in. (5 mm) I.D.
that monitored functions be limited to alarm-only or to alarm before shutdown. tubing. If using copper or rigid tubing, install at least 12 in. (305 mm) flexible
hose from the gage to the rigid tubing. This prevents damaging vibration from
Alarm Before Shutdown Models reaching the gage. For most models a pulsation orifice, within the pressure port,
The 20PABS, A20PABS, 25PABS and A25PABS feature a front limit contact for is provided and it is remov- Panel Mounting
equipment shut-down and an internal SPDT snap switch for Alarm Before Shut- able for cleaning (Figure 2). Bracket
Down. When the low side (preset point) of the snap switch trips, the N.C. terminal 2. Connect tubing to the 1/8-27
completes a circuit to activate an alarm. A continued decrease in pressure will com- NPTM port. Use of non-hard-
plete the shutdown circuit. An increase in pressure of approximately 10% of scale is ening thread sealing com-
necessary before the snap-switch (alarm) will RESET and open the circuit. Gage
pound is recommended
NOTE: Face contact shut-down limit setting and snap switch low point are fac- although thread is “dry seal”. Pressure
tory-set; specify when ordering if setting is other than standard. Port tubing
IMPORTANT: Make sure or hose
NOT to foul pressure orifices Pulsation
Typical TATTLETALE® Magnetic Switch with sealant. NEVER exceed Wire Lead Orifice Wrench
Murphy manufactures several, patented Magnetic Switches for protection of the pilot maximum pressure rating for
duty SWICHGAGE® contacts and to ensure positive shut-down of equipment. There
are Magnetic Switches for CD ignition, Magneto, Battery systems and electric motor
the gage range; see chart on p-2. Figure 2
driven equipment. TATTLETALE® annunciators show the cause of shut-down. The
first one to trip will lockout all other TATTLETALE® annunciators. Be sure the type
of Magnetic Switch/TATTLETALE® matches the power source used to trip it.
IMPORTANT: SWICHGAGE® instruments, Magnetic Switches and shut-
down or alarm devices, properly used, are effective tools in any preventive main-
NOTE: At equipment start-up (for models not having a built-in time delay) the reset but-
tenance program. For optimum performance, check these tools periodically: look
ton must be held in until normal operation occurs, or an external time delay may be
for frozen pointers, kinked/worn tubing, broken wiring or loose connections;
used. Instructions are packed with each Magnetic Switch/TATTLETALE®.
operate the contacts and watch for expected results. Replace damaged/worn parts;
clean/repair as necessary. Check for correct/complete wiring, unbroken insulation
and no accidental grounds. DO NOT run shut-down wires with ignition wiring.
Products covered by this literature comply with EMC Council directive Check all tubing and connections for leaks. Mount Magnetic Switches and valves
89/336/EEC regarding electromagnetic compatibility except as noted. upright, to prevent moisture collection.
1
Pressure Ranges and Factory Settings
Ranges Available Maximum Std. Settings* Hi Settings** 20/25PABS Settings Start-up Lockout Settings
Low Alarm† Contact Lockout Release (max.)
psi Bar Pressure psi Bar psi Bar psi Bar psi Bar psi Bar psi Bar psi Bar
0-15 (103) 1.0 2 x scale 3 (21) 0.2 12 (83) 0.8 3 (21) 0.2 6 (41) 0.3 3 (21) 0.2 4 (28) 0.3 6 (41) 0.4
0-30 (207) 2.0 2 x scale 7 (48) 0.4 24 (165) 1.6 7 (48) 0.4 10 (69) 0.6 4 (28) 0.4 7 (48) 0.5 10 (69) 0.7
0-50 (345) 3.5 2 x scale 10 (69) 0.8 40 (276) 2.8 10 (69) 0.8 13 (90) 1.0 10 (69) 0.5 13 (90) 1.0 20 (138) 1.4
0-75 (517) 5.0 2 x scale 15 (103) 1.0 60 (414) 4.0 15 (103) 1.0 18 (124) 1.5 10 (69) 0.7 15 (103) 1.0 23 (159) 1.6
0-100 (690) 7.0 2 x scale 20 (138) 1.5 80 (552) 5.5 20 (138) 1.0 23 (159) 1.5 20 (138) 1.0 25 (173) 2.0 35 (241) 2.4
0-150 (1.0 MPa) 10 2 x scale 30 (207) 2.0 120 (827) 8.0 30 (207) 1.5 33 (228) 2.0 20 (138) 1.5 30 (207) 2.0 45 (310) 3.1
0-200 (1.4 MPa) 14 2 x scale 50 (345) 3.0 150 (1 MPa) 10 50 (345) 3.0 53 (365) 4.0 40 (276) 3.0 50 (345) 3.5 70 (482) 4.8
0-300 (2.1 MPa) 20 1-2/3 x scale 75 (517) 5.0 225 (1.6 MPa) 15 75 (517) 5.0 78 (538) 5.0 50 (345) 3.5 75 (517) 5.0 105 (724) 7.2
0-400 (2.8 MPa) 28 1-1/4 x scale 150 (1 MPa) 7.0 300 (2.1 MPa) 20 75 (517) 5.0 150 (1MPa) 10 100 (690) 6.0 ––– 7.0 150 (1MPa) 10
Values in ( ) are mathematical conversions from psi to kPa/MPa–they do not reflect second scale range. U.S.A. standard scale is psi/kPa; U.K. standard scale is psi/bar. Consult factory for other scales.
* Standard setting for 20P/25P and 20PE/25PE models.
** Low settings for Hi/Lo option same as standard settings. Hi/Lo option available for 20P/25P models only.
† SPDT Snap-switch is the alarm switch.
Connecting Vacuum Models

The vacuum SWICHGAGE®/MURPHYGAGE® measures intake manifold vac- Panel
uum and gives an indication of the load applied to the engine. Tube or
1. Mount the gage in a suitable location so that the face is visible and easily Port
Fittings
Tubing
accessible.
Gage
CAUTION: Make SURE NOT TO FOUL the pressure orifices with
pipe dope or dirt or the SWICHGAGE® instrument will not operate.
2. Connect suitable tubing to the 1/8-27 NPT port of the gage and to an open Wire
Lead(s)
port in the intake manifold. Mounting kit V5179 is suggested and includes Intake
tubing and necessary fittings. The manifold fitting is 1/4 NPT. Figure 3 Manifold
Fittings
shows a typical mounting using V5179 kit. A Murphy PD2160 is also recom- PD2160
mended. Intake
Pulsation
Dampener
3. Be sure connections are tight—gage will not operate properly if line leaks. Figure 3 Manifold
Connecting Differential Pressure Models

Differential pressure models are typically applied to indicate restriction in oil/fuel fil- 2. You MUST use a second wrench on the Low Pressure port when tightening tube
ters. The “High” pressure port (center mounted) is piped to the Inlet side of the filter. fittings. (Figure 4). Notice that a wrench is used for holding the low pressure port
The “Low” pressure port (top center mounted) is piped to the Outlet side of the filter. while a second wrench will tighten the pressure tubing/hose fitting onto the port.
CAUTION: Make SURE NOT TO FOUL the pressure orifices with WARNING: Failure to use a second wrench on the low pressure
pipe dope or dirt or the SWICHGAGE® instrument will not operate. port when tightening tube fittings may result in damage to the internal
pressure tubing. Do NOT overtighten connection to port.
1. To connect the high pressure tubing use at least 3/16 in. (5 mm) I.D. flexible
pressure tubing/hose and fittings. If using copper or rigid tubing, install at IMPORTANT: NEVER exceed maximum static pressure or differential pres-
least 12 in. (305 mm) flexible hose from the gage to the rigid tubing (to pre- sure ratings for your gage range; stated in chart below.
vent damaging vibration to the gage, see Figure 2).
DO NOT TWIST
Gage Case Low Pressure Port; Ranges* Max. Static Max. Differential Contact
Back View Hold Port with Wrench Available Pressure Pressure Setting
0-15 (0-103) [0-1.0] 200 (1.4) [14] 30 (207) [2.0] 10 (69) [0.8]
Figure 4 0-30 (0-207) [0-2.0] 300 (2.1) [20] 60 (414) [4.0] 20 (138) [1.0]
Attach tubing 0-50 (0-345) [0-3.5] 300 (2.1) [20] 100 (690) [7.0] 30 (207) [2.0]
with Wrench 0-75 (0-517) [0-5.0] 300 (2.1) [20] 150 (1.0) [10] 50 (345) [3.5]
0-100 (0-690) [0-7.0] 300 (2.1) [20] 200 (1.4) [14] 60 (414) [4.0]
*Values are shown in psi, (kPa/MPa) and [bar]. Values in kPa/MPa and bar are mathematical
High
High conversions from psi–they do not reflect actual second scale range.
Pressure
Pressure Port
Port
2
Setting the SWICHGAGE® contacts Testing the Contacts
1. With equipment running; use a 1/16 in. hex wrench to rotate contact until it
IMPORTANT: If the SWICHGAGE has a lockout push but- ®
ton on the face, a contact setting higher than the factory setting touches the pointer. Do NOT force contact against the gage pointer.
will make the lockout device inoperative. Equipment should shut down and/or alarm should operate. Reset the contact
For 20PE, 25PE, 25DPE, A20PE, A25PE and A25DPE models (See Figure 5).
the switch trip point CANNOT be set at either the lowest or the highest 2. VERY IMPORTANT Each time you start the machine, observe that the
extremes of the scale. Trip point MUST allow for the switch reset differential. SWICHGAGE® is indicating pressure or vacuum. Visual inspection and regu-
For adjustable switch versions, the switch point is adjustable ONLY lar testing should be normal procedure to ensure proper operation and to
over the lower half of the scale. achieve maximum results from your SWICHGAGE®.
1. All contacts are set using a 1/16 in. hex wrench (Figure 5).
PRESSURE
2. Some models such as A20PE, A25PE, etc. may not have field adjustment.
Consult the factory if in doubt. For adjustable models, 1/4 turn clock-
wise lowers switch operating point approximately 7% of scale.
3. Observe the “normal operating” pressure or vacuum readings. Set the contact
slightly below minimum reading observed or slightly above minimum pres-
sure recommended by equipment manufacturer. For differential pressure mod-
els set the contact slightly below the desired maximum differential pressure. Switch Adjustment
Figure 5 (if applicable)
Wiring Installation
WARNING: DISCONNECT ALL ELECTRICAL POWER BEFORE BEGINNING THE WIRING INSTALLATION.
FOR BATTERY IGNITION SYSTEMS, DISCONNECT THE BATTERY GROUND STRAP. FACE ADJUSTED POINT-
ER TYPE CONTACTS ARE PILOT DUTY. DO NOT EXCEED CONTACT RATINGS ON ANY SWICHGAGE® MODEL.
20 and 25 Series models wire leads are 18 AWG or 20 AWG, 12 in. (305 mm) The pictorial below shows typical wirings for each base model. Look for specific
long. A20 and A25 Series models have number 4 or number 6 screw terminals. typical wiring diagram with your base model number and wire accordingly.
When installing the SWICHGAGE® on a ungrounded panel, you MUST provide a The pointer is shown in the Shelf Position. Face adjusted pointer type contacts
ground wire from the SWICHGAGE® to a common ground. Install ONLY in a 12 are rated pilot duty 2 A @ 30 VAC/DC. Snap-switch contacts are rated 3 A @
or 24 V system. Warning lights or audible signal MUST be of the same voltage as the 30 VDC; 4 A @ 125 VAC.
battery. Current draw should NEVER exceed SWICHGAGE® contact ratings. CAUTION: On some models pointer contact and ABS switch share the same
CAUTION: Ordinary incandescent lights are damaging to SWICHGAGE® contacts. We rec- “Common”. Voltage source MUST be the same. Maximum voltage is 30 V.
ommend using our direct connected alarms TL-7 flashing lamp and/or SAH MINI-SIREN®. Consult factory for applications with 120 VAC systems.
20DP and 20P-HL and 25P-HL 20PABS and 20PE, 20DPE,

20P and 25P 25DP 20V and 25V 25PABS 25PE and 25DPE
N. C. Red N. C. Red
C. White C. White
N. O. Black N. O. Black
LOW HIGH LOW HIGH LOW
Red Black Red Black Red
A20P A20DP A20P-HL and A20V A20PABS A20PE A20DPE
LOW HIGH LOW HIGH LOW ABS SET RESET RESET SET
N. C. C N. O. N. C. C N. O. N. C. C N. O. N.C. C N.O. N. C. C N. O. N. C. C N. O.
A25P-HL and A25PABS A25PABS-HL A25PE A25DPE

A25DP A25V N.C. C N.O. N.C. C N.O. N.C. C N. O. N.C. N.O.
A25P
SET RESET SET RESET SET RESET RESET SET
LOW HIGH LOW HIGH LOW LOW HIGH

L P H L P H L P H L P H L P H L P H L P H
3
Installing The Magnetic Switch
WARNING: DISCONNECT THE BATTERY OR POWER SOURCE BEFORE BEGINNING THE INSTALLATION.
SEE SPECIFIC WIRING INSTRUCTIONS PACKED WITH EACH MAGNETIC SWITCH / TATTLETALE®.
1. Mount with electrical lugs down. Drill mounting holes in panel. NOTE: Murphy components are easily wired and maintained. Use good quality
2. Clean away burrs and filings. Position the Magnetic Switch in the wire and terminals. The type of Magnetic Switch differs for various applications.
panel, making sure the pilot stud is in place. See typical wirings below. Wiring and instructions are packed with each
3. Add decal, then washer, then nut and tighten. Magnetic Switch.
20P Pressure 20P-F Pressure 20T-F Temperature 518PH Magnetic Switch
® ®
SWICHGAGE® 117 Magnetic Switch SWICHGAGE SWICHGAGE
Y SWICHGA Y SWICHGA Y SWICHGA

PH PH G PH
G UR E®
UR
GE
UR E® M PSI M °F ®
M PSI
40 60 80 0 190 220
40 60 80 20 10 0 16
20 10 0 13 25
0 0 R
0
0 300 60 80 100 12
300 60 0 0 60 0
0 0 kPa °C G NC SW1 SW2 B
kPa
PRESSURE
PRESSURE TEMPERATURE
C S B
N.O. SWICHGAGE®
instruments
_ +
Energized To Run Devices _ + N.C. switches option Energized To Run Devices Battery
Battery
Troubleshooting
DO THIS FIRST: Look for broken wiring, frozen pointer, dirty contacts (will not make), burnt pointer or contact. Verify that all wiring is intact and con-
nections are tight. Verify that SWICHGAGE® has not been damaged (hit or dropped). Verify that there is pressure/vacuum supplied to the gage. Verify that the
SWICHGAGE® is operative (it reads). Verify that the alarm or shutdown device is fully operable; and check other components such as spark plugs, ignition, fuel
pump and filter, etc. Reset Magnetic Switch and verify that it stays latched.
SYMPTOM CAUSE TEST/REMEDY

Engine will not start. 1. Short or Open circuit, be sure the Magnetic Switch latches and puts out power to 1. Reset Magnetic Switch and make sure it stays latched. Refer to install-
the run device or removes ground (ignition). Check for power/ground at run device. ation instructions for 518PH Magnetic Switch (provided with unit).
2. Control circuit overloaded by accessories (blown fuse in Magnetic Switch). 2. Find blown fuse and replace (use 14 A fuse). Reroute the accessories.
3. False ground in control circuit. 3. Repair.
False shutdown. 1. SWICHGAGE® circuit has intermittent open or short. 1. Check all wiring and repair/replace as necessary.
2. Vibration causes the Magnetic Switch to trip. 2. Repair and relocate the switch as needed.
SWICHGAGE® closes but 1. Incomplete shutdown circuit. 1. Locate open circuit and repair.
does not trip the magnetic 2. Dirty SWICHGAGE® contacts. 2. Clean and check that contacts make.
switch or kill the engine. 3. Ignition not providing power to primary terminal post. 3. Repair ignition.
4. SWICHGAGE® case may not be grounded. 4. Ground case.
5. Incorrect Magnetic Switch for type of power. 5. Replace with correct Magnetic Switch.
Magnetic Switch tripped but 1. Open circuit between the Magnetic Switch and the shutdown device. 1.Check wiring from Magnetic Switch to shutdown device, repair or replace.
engine is still running. 2. Lost ground to kill the engine. 2. Check all wiring and connections and repair.
Pointer will not operate 1. Frozen pointer 1. Return for repair or replacement.
properly. Inaccurate reading. 2. Loose pointer spring (caused by hitting or dropping gage). 2. Return for repair or replacement.
3. Plugged pressure orifice. 3. Remove and clean.
Pointer/contact burned-in two. Without exception this condition is caused by incorrect wiring or short circuit. Recheck wiring; replace SWICHGAGE® or return for repair.
WARRANTY
A two year limited warranty on materials and workmanship is provided with this Murphy product.
Details are available on request and are packed with each unit.
In order to consistently bring you the highest quality, full featured products, we reserve the right to change our specifications and designs at any time.
FRANK W. MURPHY MANUFACTURER P.O. Box 470248; Tulsa, Oklahoma 74147; USA tel. (918) 627-3550 fax (918) 664-6146 e-mail sales@fwmurphy.com http://www.fwmurphy.com
■ FRANK W. MURPHY SOUTHERN DIVISION ■ MURPHY DE MEXICO, S.A. DE C.V. ■ MURPHY SWITCH OF CALIFORNIA
®
FRANK W.
P.O. Box 1819; Rosenberg, Texas 77471; USA Blvd. Antonio Rocha Cordero 300, Fracción del Aguaje 41343 12th Street West
MFR.
tel. (281) 342-0297 fax (281) 341-6006 San Luis Potosí, S.L.P.; México 78384 Palmdale, California 93551-1442; USA
Since 1939
e-mail sales@fwmurphy.com tel. +52-48-206264 fax +52-48-206336 tel. (661) 272-4700 fax (661) 947-7570
e-mail murmexsl@sanluis.podernet.com.mx e-mail sales@murphyswitch.com
■ FRANK W. MURPHY, LTD.
http://www.murphyswitch.com
BSI Church Rd.; Laverstock, Salisbury SP1 1QZ; U.K. ■ FRANK W. MURPHY PTE., LTD.
tel. +44 1722 410055 fax +44 1722 410088 No. 2 Tuas South Street 2, ■ MACQUARRIE CORPORATION
REG
RM
NATIONAL
ACCREDITATION e-mail sales@fwmurphy.co.uk Sprintecs Bldg., #02-01/02 1620 Hume Highway;
FI
ST OF CERTIFICATION
I
ERED BODIES
http://www.fwmurphy.co.uk Singapore 638042 Campbellfield, Vic 3061; Australia
USA–ISO 9001 FM 28221 tel. +65 863-1398 fax +65 863-0208 tel. +61 3 9358-5555 fax +61 3 9358-5558
4 UK–ISO 9002 FM 29422 ■ FRANK W. MURPHY FRANCE
e-mail fwmsales@fwmurphy.com.sg e-mail murphy@macquarrie.com.au
Printed in U.S.A. tel. +33 1 30 762626 fax +33 1 30 763989
Model P-55U
Pressurized
Suction Pumps
Model P-55U Pressurized Suction Pumps Operating
Operating Instructions Instructions
Pressurized Suction Pumps
• Install pump in lubricator reservoir.
• Loosen union nut on pump outlet and fill pump

with oil and prime by manually pumping
flushing unit until air free oil is observed around For additional information contact:
Premier Lubrication Systems
union nut. It may be necessary to install a
14105 Packard Street
manual hand priming gun in the inlet of the
Houston, Texas 77040
pump to expel the air from pump. After this is Telephone (713) 462-5255
accomplished tighten union nut. Fax (713) 462-7919
Flow Rate
• Loosen lock nut on flushing unit.
• Turn the flushing unit counter clockwise to

increase flow.
• Turn flushing unit clockwise to decrease flow.
• Tighten lock nut when desired flow rate is

achieved.
Pump Outlet, 1/8” NPT
Pump Inlet, 1/8” NPT
Union Nut
Lock Nut
Premier Plunger Maximum Operating

Part Number Size Pressure
92150 3/16” Plunger 6,000 PSI
91222 1/4” Plunger 8,000 PSI
91223 3/8” Plunger 3,500 PSI
© Premier Lubrication Systems, 1998

“Your Single Source For Any Lubrication Application” DropsA
SMX
Divider
Valves
GENERAL FEATURES
• Integral Porting Adapter for Simple Single to Twin Outlet

Conversion, Reduces Inventory Levels
• Air Bleeds Built Into Base Plate
• Maximum Pressure 7,200 PSI (500 BAR)
• Operates With Oil or Grease
• Full Monitoring Capability
• NPTF-Metric-BSP-SAE Threads Available
• Modular Design—Base and Metering Elements
• Zinc Plated Components
ADVATAGES
• Modular Design Eliminates Tie Rods

• Metering Elements Can Be Serviced Without Disturbing Piping
or Tubing METERING ELEMENTS
• Internal Cross Porting
• Auxiliary By-Pass Element Available The Metering Elements are fixed to the base by means of two
cap screws (provided).
• Easy Conversion From Twin to Single, No Need to Stock Twin
and Single Metering Elements The SMX Metering Elements are available in a wide range of
• No Limitation To The Maximum Number of Metering Elements deliveries (See Chart on Page 2). Cycle Indicator Pins are
available on most size elements (See Chart on Page 2).
Notes:
A By-Pass element is also available which allows an addition or
1. A Minimum of 3 Metering Elements is Required to Operate The reduction of lubrication points at any time without having to
Assembly. disconnect any piping or tubing.
2. Each Base And Metering Element Undergoes a Thermal
Explosive Process to Eliminate Foreign Matter. Bridge Elements (Internally Cross Ported) are available. These
interconnect and discharge into the next element.
DESCRIPTION
The Metering Elements are supplied with either one or two
The DropsA SMX is a Modular Design Series Progressive Divider outlets, Conversion Plugs are available for field conversion from
Valve Consisting of Two Main Parts; the Base and Metering one to two outlets (See Chart Below).
Elements.
All Metering Elements are fully interchangeable in various
BASE positions on the base.
The Base is made up of a minimum of three segments:
• Inlet Base Section

• Intermediate Base Section Conversion Plugs
• End Base Section
Plug Type Plug Part No. Plug Color
And can be increased in number by the addition of Intermediate
Base Sections. “S” Single Outlet 641708 Silver
This revolutionary system makes the assembly easy and flexible;
there is no need to determine in advance the size of the base, just
“T” Two Outlets 641709 Gold
add on intermediate base sections by means of Threaded Inserts
and Cap Screws (Patented).
For Additional Information Contact: Telephone / Fax / E-Mail Information

PROGRESSIVE EQUIPMENT INC. Document No. P20-010 Tel: 713.462.1061
14028 Aston Avenue Date Published 03-28-2000 Fax: 713.462.4027
Houston, Texas 77040 USA E-Mail: sales@progressive-equipment.com
Base Plate Assemblies Chart (Standard Mounting) Metering Element Chart
No. of Elements Part Number Metering Delivery In3 Delivery In3 Part
Element Size (Twin) (Single) Number
3 643523 SMX-08 .005 .010 641516
4 643524 SMX-12 .0075 .015 641790
5 643525 SMX-16 .010 .020 641517
6 643526 SMX-25 .015 .030 641518
SMX-35 .020 .040 641519

7 643527
SMX-40 .025 .050 641520
8 643528
SMX-50 .030 .060 641521
9 643529
SMX-60 .035 .070 641522
Note: Bases For 10 or More Sections are available, contact
SMX-65 .040 .080 641523
Progressive Equipment for Part No. / Ordering Information.
SMX-00 By-Pass By-Pass 641514
TECHNICAL DATA
Maximum Pressure: 7,200 PSI (500 BAR)

Note: 3 Working Metering Elements are Required to Complete
an Assembly. A By-Pass is not considered a Working Element.
Minimum Pressure: 215 PSI (15 BAR)
O-Ring Material: Buna, Standard * Viton, Optional

Adapter Single/Twin
Temperature Range:
Buna Seals: -220 F (-300 C) to +2120 F (+1000 C)
Viton Seals: -40 F (-250 C) to + 3920 F (+2000 C)
Maximum No. of Strokes Per Minute: 500* Depending on Pressure

and Delivery.
Oil Viscosity: Minimum 15 cSt (77.31 SSU)

Top View of Metering Element
Grease: Maximum 200 ASTM (NLGI-4)
Weight of Single Element: .68 Lb. (0.31 Kg)

O-Ring (9 Per Element)
Inlet Thread: 1/4” NPT
Outlet Thread: 1/8” NPT
(Consult Pro-Gress for Metric Sizes)
MONITORING OF PISTON MOVEMENT

Bottom View of Metering Element
The following Types of Switches are available to monitor
Piston movement:
• DNFT—Digital No-Flow Timers (Request DNFT Brochure)

PIN INDICATORS (High Pressure, Blocked or
• DNFT—Proximity Switch (Request DNFT Proximity Switch Plugged Line Indication).
Brochure)
• Pin Indicator, Pressure Type w/ Memory—Available in
• DELIRON—Magnetic Cycle Indicator (leak-proof) pressure ratings of: 1500, 2000, 2500, 3000, 3500, 4000
and 5000 PSI.
169LIT Prx Swi
PROXIMITY SWITCH
07/03/01
SPECIFICATIONS DL-PRX FOR

TRABON, LINCOLN
R R
Material......................... .......Stainless Steel, Aluminum

MANZEL & DROPSA
R R
o o
Temperature Range...........................-40 F to +185 F
Switch Rating....10 VA / 200 VDC ½ AMP MAX 125 VAC DIVIDER BLOCK LUBRICATION SYSTEMS
MINIMUM BREAKDOWN 300 VDC
Epoxy Encapsulated............UL LISTED EL-CAST VFR 641
MAGNET SWITCH HOUSING
CLASS 1, Div 1 Grps A,B,C,D HOUSING (B)
#24 AWG 18" LEADS (3)
NRTL/C
LR108334-1 (C)
YELLOW
YELLOW
(Switch
Connections)
1.125"
MAGNET GREEN
(H) (Ground)
ALLEN HEAD SPACER
O-RING SET SCREWS SPRING
3.250" OR METAL GASKET (A)
(F)
INSTALLATION AND ADJUSTMENT PROCEDURE

0-RING SWITCH HOUSING
1. Loosen all (2) Allen head set screws (A) on switch housing (B) and (F)
INTERNAL VIEW OF (B)
remove magnet housing (C). Do not remove magnet, spring, and spacer DIVIDER VALVE HOUSING MAGNET
(E) (H)
from magnet housing.
24S
2. Remove end plug (D) from divider valve where proximity switch will
be installed. Proximity switch can be installed on any available divider
24S MAGNET
valve section. HOUSING WIRE LEADS
3. Screw magnet housing (C) into end of divider valve. Torque to 15 foot 24S (C) (I)
pounds max. Be sure 0-ring or metal gasket (F) is in place on magnet END PLUG
(D)
housing (C) if required. DIVIDER VALVE
4. Slide switch housing (B) all the way onto magnet housing (C). ASSEMBLY
(G)
Connect ohmmeter to yellow switch leads. Do not tighten set screws at
this time.
5.To properly adjust switch housing (B), divider valve assembly (G)
must be cycling so magnet (H) is moving back and forth. This can be ORDERING INFORMATION
achieved with lubrication system functioning or by manually pumping MODEL DESCRIPTION PART
clean oil through divider valve assembly with a hand pump. NUMBER
6. If a cycle is not detected, adjustment is made by sliding switch DL-D-PRX DROPSA 000169
housing (B) out in 1/16" increments. Continuity meter connected to
yellow wires will indicate a switch closure. Adjust 1/16" out until correct DL-L-PRX LINCOLN - O-RING STYLE 000170
adjustment is confirmed. Torque set screws to 25 inch pounds max.
TRABON - GASKET STYLE
7. Use 10 to 12 inches of flexible conduit on the switch housing for ease DL-TG-PRX “1994” AND EARLIER
000171
of adjustment or maintenance. All conduit and connections should be DL-TO-PRX
TRABON - O-RING STYLE
000172
“1995” AND LATER
appropriate for area classification. CAUTION: Conduit and fittings must
be supported to avoid bending magnet assembly.
DISTRIBUTED BY
Odessa, TX USA
1-800-337-3412 www.noflo.com
Manufactured and Assembled in the U.S.A. By DELIRON LIMITED
*ALL TRADEMARK NAMES ARE THE PROPERTY OF THEIR RESPECTIVE COMPANIES AND ARE NOT ASSOCIATED WITH DELIRON LIMITED.
Cycle Indicator 073LIT DCI-D
09.08.01
Model DCI-D - Part# DL 3073

MONITORS AND DISPLAYS OPERATION OF DIVIDER BLOCK LUBRICATION SYSTEMS
0.625" (5/8")
2.300”
HIGHLY VISIBLE SPECIFICATIONS

Material.....................................................Stainless Steel
STAINLESS STEEL HOUSING Application .......Monitors Fluid(Oil)or Grease Systems
Rated Pressure...................................................6500 PSI
FLUID or GREASE SYSTEMS Indication....Highly Visible Snap-Action Bright Orange
LEFT or RIGHT MOUNTING

DESCRIPTION
SNAP-ACTION INDICATION The DELIRON CYCLE INDICATOR is a cost-
effective and easy to install lubrication monitoring
device. It has a custom machined stainless steel
TOTALLY SEALED
housing and powerful internal magnet assembly
built for industrial use. It is totally sealed and can
EASY TO INSTALL accurately monitor fluid or grease systems. It can
be installed on any section and either side of a
ANY SIZE DIVIDER BLOCK divider block. The highly visible indicator has a
SECTION snap-action movement which makes it easy for the
user to see as well as determine the precise timing
of each divider valve cycle.
ORDERING INFORMATION
TM
MODEL DCI-TO................Trabon O-Ring.................P/N# Dl3070
TM
MODEL DCI-D .................Trabon Gasket.................P/N# Dl3071
MODEL DCI-L...................Lincoln.............................P/N# Dl3072
TM
MODEL DCI-D .................Dropsa..............................P/N# Dl3073

TM
Odessa, TX USA
1-800-337-3412 www.noflo.com
Manufactured and Assembled in the U.S.A. By DELIRON LIMITED
*ALL TRADEMARK NAMES ARE THE PROPERTY OF THEIR RESPECTIVE COMPANIES AND ARE NOT ASSOCIATED WITH DELIRON LIMITED.
V-SERIES VALVES
V-SERIES
VALVES
Standard Standard Stainless Steel Handwheel Handwheel
with Screw with Flange with Screw with Screw with Flange
Connections Connections Connections Connections Connections
APPLICATION Widely used in a variety of applications, the “V”

series valves are ideally suited in hydraulic and
The Fulflo “V” Series range in size from 1/4” lubricating systems for load regulation and
through 2” and operate efficiently with liquids of system protection. Special trim or packings are
any viscosity at pressures from 2 to 1000 P.S.I. available for use with fire resisting fluids and
The “V” series valves are available in flange or other liquids of this type. Unusual applications
screw type...cartridge or handwheel in a choice and special requirements should be referred to
of brass, cast iron, steel and stainless steel. our engineering staff for recommendation.
INSTALLATION should be piped back to the tank. Care must be

taken to have the discharge well below the oil
Fulflo valves can be mounted in any position. A level in the tank to prevent air entrainment and
tee may be inserted in the pump discharge line erratic operation.
to mount the valve. The correct size of valve
should be installed, preferably matching the Only if the valve is used as safety or overload
pump discharge line. Screw the valve into the relief and operates infrequently may its
nipple in the tee, or in the case of the flange discharge be piped back into the pump suction
style, bolt the valve to the companion flange line. Frequent or continuous operation under
screwed into the nipple. When the valve is used these conditions will cause excessive heating of
for frequent bypassing of oil pressure, its outlet the oil and possible damage.
11
V-SERIES
SETTING VALVES having a flow meter in the pump discharge line must
be available. With a valve adjusted for cracking
Valves may be set with a hydraulic hand pump for pressure as above, continue closing bypass until the
cracking pressure. If a test stand is available, valve required flow registers on the flow meter and observe
should be connected to the discharge header with the pressure. Readjust pressure, if necessary, to obtain
pump bypass open, and the bypass gradually closed desired pressure at desired flow.
until the desired pressure registers on the gauge.
Adjust valve adjusting screw until valve slightly bleeds
at the set bypass pressure and lock adjusting screw. MAINTENANCE
Fulflo valves are not designed to be positive shut-off, Fulflo valves provide reliable “chatter-free” operation
and will pass a minimal amount of leakage before the when the system is free of abrasives and foreign
V-SERIES
VALVES
set pressure. If a valve is required to bypass a given matter. Continuous filtration of the liquid used is
amount of fluid at a given pressure, a test stand strongly recommended.
TYPICAL DISASSEMBLY OF STANDARD TYPE VALVE
To dismantle valve for inspection or cleaning:

G 1. Remove cap “B”
2. Remove O-Ring “E”
3. Remove lock nut “F”
B
I 4. Remove adjusting screw “C”
5. Remove retainer “D”
E H 6. Remove spring “G”
7. Remove piston “I”
F 8. Remove stop ring “H” (Not Recommended)
A (Special tooling is required to install new stop ring.)
C Inspect valve bore and piston for wear and scoring. Replace
broken or damaged parts. Clean all parts thoroughly and
re-assemble by reversing the above procedure.
D
TYPICAL DISASSEMBLY OF HANDWHEEL TYPE VALVE

To dismantle the valve for inspection or cleaning:
1. Release spring tension by backing off handwheel as far as it
will go.
2. Remove lock nut “A” or set screw and take off handwheel “B”
3. Remove lock nut “D”
4. Unscrew and remove gland “E”
5. Unscrew and remove bonnet “F”
J 6. Remove O-Ring “H”
A
F 7. Remove adjusting screw “C” (turn clockwise and pull out from
B bottom of bonnet “F”)
D K 8. Remove O-ring packing “G”
9. Remove spring “J”
E H 10. Remove piston “K”
11. Remove stop ring “L” (Not Recommended)
G L (Special tooling is required to install new stop ring.)
Inspect valve bore and piston for wear or scoring. Replace broken
C or damaged parts. Clean all parts thoroughly and re-assemble by
reversing the above procedure.
I
12
V-SERIES
ASSEMBLY NUMBER IDENTIFICATION CHART
Symbol No. Designation Code Description
1 Style None Standard Model
H Handwheel Model
2 Series V
3 Material J Cast iron
B Brass
S Steel
SS 316 Stainless Steel
4 Connections None Screw Connections
F Flange Connections 300# Flange Class Standard (250# Flange Class - Cast Iron Standard)
V-SERIES
VALVES
5 Size -1 1/4”
-2 3/8”
-3 1/2”
-4 3/4”
-5 1”
-6 11/4”
-7 11/2”
-8 2”
6,7,8 ASA None 300# Flange Standard (no designation required)
Flange -150
Rating -600
9 Flange A Raised Face, Staggered Bolt Centers (standard on all Flange rating)
Style B Smooth Face, Staggered Bolt Centers
150# & 600# C Raised Face, Bolts on Valve Centerline
Only D Smooth Face, Bolts on Valve Centerlne
10 O-Ring R Buna O-Ring Cap Seal (standard)
Material RV Viton O-Ring Cap Seal
RS Silicone O-Ring Cap Seal
RT Teflon O-Ring Cap Seal (standard on VSS Series)
RA Aflas O-Ring Cap Seal
11 Options SP Steel Parts (used on cast iron only)
P Panel Mount on Handwheel Series
12 Piston /HS Hardened Steel
Material /SS 416 Stainless Steel
/3SS 303 Stainless Steel
13 Spring AS
US
WS
XS
YS
ZS
14 Setting Desired Pressure Setting
EXAMPLES:
VJ-1RVSP/HS/WS VJF-5R/HS/WS VJF-5-150AR/HS/WS
V J -1 RV SP /HS WS V J F -5 R /HS WS V J F -5 -150 A R /HS WS
Series Cast Iron 1/4” Viton O-Ring Steel Parts H.S. Piston WS Spring Series Cast Iron Flanged 1” Buna O-Ring H.S. Piston WS Spring Series Cast Iron Flanged 1” Rating Style Buna O-Ring H.S. Piston WS Spring
NOTE: Stainless steel pistons are supplied on brass valves, unless hardened steel is specified. Hardened steel pistons are supplied on cast iron or steel unless stainless steel is
specified. Buna O-Rings are supplied as standard unless other material is specified.
STANDARD PRESSURE RANGE CHART

Valve Valve SPRING PRESSURE AND IDENTIFICATION NO.
Pipe Flange BLACK-AS RED-US GREEN-WS YELLOW-XS WHITE-YS BLUE-ZS PURPLE-TS BROWN-RS
Size Size
Low High Low High Low High Low High Low High Low High Low High Low High
1/4” 3 15 7 35 30 100 60 175 150 350 300 500 400 600 550 750
3/8” 3 15 7 35 30 100 60 175 150 350 300 500 400 600 550 750
1/2” 3 15 7 35 30 100 60 175 150 350 300 500 400 600 550 750
3/4” 3 15 7 35 30 100 60 175 150 350 300 500
1” 1” 3 15 7 35 30 100 60 175 150 350 300 500
11/4” 11/4” 3 15 7 35 30 100 60 175 150 350 300 500
11/2” 11/2” 3 15 7 35 30 100 60 175 150 350 300 500
2” 2” 3 15 7 35 30 100 60 175 150 350 250 600
13
VJF Cast Iron VSF Steel
V-SERIES VBF Brass VSSF Stainless Steel VJF-SP Cast Iron with Steel Parts
DIMENSIONS DIMENSIONS IN INCHES
Valve
Size AA BB
J B
C 1” 91/2” 31/2”
F
11/4” 1013/16” 33/4”
K E
11/2” 127/16” 41/16”
D
2” 149/16” 49/16”
V-SERIES
G
VALVES
Note: Dimensions reflect
CAP 150# and 300# only
A
AA REF.
(GASKET SEAL) 45˚
I
45˚
221/2˚
PIPE SIZE
45˚
H
221/2˚
BB
-------
-------
-------
-------
FOR 2” VALVE ONLY
PIPE SIZE
BB
PARTS LIST
SYM. NAME MODEL VALVE SIZE
1” 11/4” 11/2” 2”
VJF, VJF-SP 500-F 600-F 700-F 800-F
VBF 500-BF 600-BF 700-BF 800-BF
A BODY VSF 500-SF 600-SF 700-SF 800-SF
VSSF 500-SSF 600-SSF 700-SSF 800-SSF
VJF, VJF-SP 501-R 601-R 701-R 801-R
CAP VBF 501-BR 601-BR 701-BR 801-BR
B (O-RING SEAL) VSF 501-SR 601-SR 701-SR 801-SR
VSSF 501-SSR 601-SSR 701-SSR 801-SSR
VJF, VBF 502-B 602-B 702-B 802-B
C ADJUSTING VSF, VJF-SP 502-S 602-S 702-S 802-S
SCREW VSSF 502-SS 602-SS 702-SS 802-SS
VJF, VBF 503-B 603-B 703-B 803-B
D RETAINER VSF, VJF-SP 503-S 603-S 703-S 803-S
VSSF 503-SS 603-SS 703-SS 803-SS
VJF, VJF-SP 504* 604* 704* 804*
E O-RING ✝ VBF, VSF 504-* 604-* 704-* 804-*
VSSF 504-RT 604-RT 704-RT 804-RT
VJF, VJF-SP 505-S 605-S 705-S 805-S
F LOCK NUT VBF, VSF 505-S 605-S 705-S 805-S
VSSF 505-SS 605-SS 705-SS 805-SS
G SPRING ✝ ALL MODELS 507-** 607-** 707-** 807-**
VJF, VBF 508-B 608-B 708-B 808-B
H STOP RING VJF-SP, VSF 508-S 608-S 708-S 808-S
VSSF 508-SS 608-SS 708-SS 808-SS
HARDENED STEEL 506 606 706 806
I PISTON ✝ 416 STAINLESS STEEL 506-A 606-A 706-A 806-A
303 STAINLESS STEEL 506-SS 606-SS 706-SS 806-SS
VJF, VJF-SP 501 601 701 801
J CAP VBF 501-B 601-B 701-B 801-B
(GASKET SEAL)
VSF 501-S 601-S 701-S 801-S
VJF, VBF 504 604 704 804
K GASKET ✝ VJF-SP, VSF 504-S 604-S 704-S 804-S
* See o-ring selection chart
** See spring pressure chart
✝ Recommended spare parts
15

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SERVICE MANUAL

(1) 7.0-INCH STROKE TYPE HOSS

15.0 + 15.0 + 9.50 + 9.50 X 7HOSS4

ENERFLEX ENERGY SYSTEMS, INC

CUSTOMER P.O. NO. 4500036132

D-R GFC ORDER: C2314

UNIT SERIAL NUMBERS:

Gas Field Compressors

© Dresser-Rand Company 2013

How To Navigate The DRESSER-RAND

11 Will appear when page overfills frame

2. BOOKMARKS - Getting To Sections

2.A.2. - Click on “Window” and Go To

a. Click on the plus (+) sign to show the sub-headings.

Similar arrows and boxes are found in the Bookmark window

As you scroll through the pages using the vertical arrowheads,

3. NAVIGATING IN SECTIONS & BETWEEN SECTIONS

4. TRACKING BACK AND FORTH THROUGH A SEQUENCE OF PAGES

As with the paging arrowheads at the top of the page, when

4.A. 5.A. 6.A.

1. The size may be adjusted by selecting;

1. “Zoom In” makes image larger.

2. “Zoom Out” makes image smaller.

6. LOCATING SPECIFIC INFORMATION

1. Click the Binoculars icon.

3. Click the “Find” button.

TO THE D-R EQUIPMENT OWNER/OPERATOR:

MANUAL HOLDER INFORMATION - FIRST

MANUAL HOLDER INFORMATION - SECOND

ENTERED DESCRIPTION OF CHANGE REVISION

SAFETY PRECAUTIONS ..................................................................................... PG-662-F

SAFETY LABELS.................................................................................................. PG-2914-F

PLACEMENT DRAWING ...................................................................................... G12157C

SERVICE CENTERS ............................................................................................ PG-2697-P

TECHNICAL COMPRESSOR TRAINING............................................................. PG-2551-E

SERVICE LITERATURE READER SURVEY ....................................................... PG-2915-A

METRIC CONVERSIONS ..................................................................................... PG-732-D

REFER ALL COMMUNICATIONS TO THE NEAREST DRESSER-RAND COMPANY

SIGNAL WORDS ARE USED TO IDENTIFY LEVELS OF HAZARD SERIOUSNESS. THEIR

● DEGREE OF SEVERITY (minor injury, severe injury, death)

● THE PROBABILITY OF SEVERITY (will result, could result)

NOTES are used to highlight certain operating or maintenance conditions or

The installation, operation and maintenance of a compressor and auxiliary components

● Piping subject to temperatures in excess of 175ºF (80ºC) which may be touched by

• Compressor manufacturers utilize elastomer seals (O-rings) found in today’s

● Whenever the compressor is shut down because overheating is suspected, a minimum

● If IN DOUBT as to whether a valve is inlet or discharge, or as to which cylinder valve

● Established operating and maintenance procedures, as well as basic safety

UTAH – North Salt Lake City Dresser-Rand Service Center

International Service Centers... Next Pages

INDONESIA – Banten – Cilegon PT Dresser-Rand Services Indonesia

For more information, contact your Dresser-Rand Sales Representative or the

METRIC CONVERSION EQUIVALENTS

The metric conversion equivalents listed below

inches (in) 25.4 millimetres (mm)

pounds (lbs) 0.454 kilograms (kg)

gallons (gals) 3.785 litres (L)

horsepower (HP) 0.746 kilowatts (kW)

British Thermal Units (Btu) 1055 joules (j)

degrees Fahrenheit (°F) 0.556 (°F - 32) degrees Celsius (°C)