b16 25
b16 25
b16 25
A N A M E R I C A N A T I O N A S
L T A N D A R D
BUTTWElOlNG EMDS
ASME B16.25-1NU7
(Revision of ASME B16.25-1!!2)
The 1997 edition of this Standard is being issued with an automatic addenda
subscription service. The use of an addenda allows revisions made in
response to public review comments or committee actions to be published
as necessary; revisions published in addenda will become effective 6 months
after the Date of Issuance of the addenda. The next edition of this Standard
is scheduled for publication in 2002.
This code or standard was developed under procedures accredited as meeting the criteria for
American National Standards. The Consensus Committee that approved the code or standard
was balanced to assure that individuals from competent and concerned interests have had an
opportunity to participate. The proposed code or standard was made available for public review
and comment which provides an opportunity for additional public input from industry, academia,
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ASME does not "approve," "rate," or "endorse" any item, construction, proprietary device,
or activity.
ASME does not take any position with respectto the validity of any patent rights asserted in
connection with any items mentioned in this document, and does not undertake to insure anyone
of any applicable LettersPatent, nor assume
utilizing a standard against liability for infringement
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ASME procedures and policies which preclude the issuance of interpretations by individual
volunteers.
Copyright 0 1997 by
THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS
All Rights Reserved
Printed in U.S.A.
. ..
111
OFFICERS
W. N. McLean, Chair
R. A. Schmidt, Vice Chair
K. Ciciora, Secretary
COMMllTEE PERSONNEL
W. Ballis, Consultant, Columbus, Ohio
R. R. Brodin, Fisher Controls International, Inc., Marshalltown, Iowa
K. Ciciora, ASME, New York, New York
M.A. Clark, NIBCO, Inc., Elkhart, Indiana
A. Cohen, Copper Development Association, New York, New York
W. C. Farrell, Jr., Consultant, Birmingham, Alabama
D. R. Frikken, Monsanto Co., St. Louis, Missouri
M. W. Garland, Frick Company, Waynesboro, Pennsylvania
J. C. Inch, Mueller Refrigeration Products Co., Hartsville, Tennessee
G. A. Jolly, Vogt Valve Co., Louisville, Kentucky
W. G. Knecht, Consultant, Williamsport, Pennsylvania
R. Koester, The William Powell Co., Cincinnati, Ohio
W. N. McLean, Newco Valves, Palos Park, Illinois
R. A. Schmidt, Ladish Co., Russellville, Arkansas
W. M. Stephan, Flexitallic, Inc., Pennsauken, New Jersey
T. F. Stroud, Ductile Iron Pipe Research Association, Birmingham, Alabama
R. E. White, Richard E. White & Associates, South Bend, Indiana
0. A. Williams, Southern Company Services, Birmingham, Alabama
L. A. Willis, Dow Chemical Co., Freeport, Texas
W. R. Worley, Union Carbide Corp., South Charleston, West Virginia
1 Scope ............................................................. 1
2 Transition Contours .............................................. 1
3 Welding Bevel
Design ............................................ 1
4 Preparation of Inside Diameter of Welding End . . . . . . . . . . . . . . . . . . 5
5 Tolerances ........................................................ 6
Figures
1 Maximum
Envelope for Welding End Transitions .................... 2
2 Weld
Bevels for Wall Thickness Not Over 22 mrn (0.88 in.) . . . . . . . . . 3
3 Weld
Bevel Details for Wall Thickness Over 22 mm (0.88 in.) ....... 4
4 Weld
Bevel Details for GTAWRoot
Pass [Wall Thickness Over
3 mm (0.12 in.) to 10 mm (0.38 in.), Inclusive] . . . . . . . . . . . . . . . . . . . 5
5 Weld
Bevel Details for GTAWRoot
Pass [Wall Thickness Over
10 mm (0.38 in.) to 25 mm (1.0 in.), Inclusive] . . . . . . . . . . . . . . . . . . . 6
6 Weld
Bevel Details for GTAW
Root
Pass
[Wall Thickness Over 25 mm (1.0 in.)] ........................... 7
Table
I Dimensions of Welding
Ends ..................................... 8
Annexes
A Inch Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
B Quality System Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
C References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
SPECIAL NOTE:
The interpretations to ASME B16.25 are included in this Edition as a separate section for the users convenience.
This section. however.is notpartofthe Standard.
vii
BUTTWELDING ENDS
Component or Fitting
) Maximum [Note (2)l
[Note
(5)l I Radius 2 0.05 tmin [Note
(5)l
1
-----I
Inside
I
2t,in transitionregion
NOTES:
(1) The value of t m i n is whichever of the following is applicable:
(a) the minimum ordered wall thickness of the pipe;
(b) 0.875 times the nominal wall thickness of pipe ordered to a pipe schedule wall thickness that has an under-tolerance of 12.596;
(c) the minimum ordered wall thickness of the cylindrical welding end of a component or fitting (or the thinner of the two) whenthe
joint is between two components.
(2) The maximum thickness at the end of the component is:
(a) the greater of tmin + 4 m m (0.16 in.) or 1.15tmin when ordered on a minimum wall basis;
(b) the greater of tmin + 4 mm (0.16 in.) or l.lOtnwhen om ordered on a nominal wall basis.
(3) Weld bevel shown is for illustration only.
(4) The weld reinforcement permitted by applicable code may lie outside the maximum envelooe.
(5)Where transitions using maximum slope do notintersect inside or outside surface, as shown by phantom outlines, maximum slopes
shown or alternate radii shall be used.
i
\
---J 8
I
[Note (2)1
(0.06 20.03)
A
1 A
c +0.25 - 0
(c) Welding End Detail for Joint Using Continuous (d) Welding End Detail for Joint Using Continuous
Rectangular Backing Ring Tapered Backing Ring
GENERAL NOTES:
(a) Broken lines denote maximum envelope for transitions from welding bevel and root
face into body of component.
See Fig. 1 for details.
(b) See Section 5 for tolerances other than those given these
in sketches.
(C) Purchase order must specify contour of any backing ring tobe used.
(d) Linear dimensions are in millimeters with inchvalues in parentheses.
NOTES:
(1) Internal surface may be as-formed or machined for dimension 6 at root face. Contour within the envelope shallbe in accordance
with Section 2.
(21 Intersections should be slightly rounded,
FIG. 2 WELD BEVELS FOR WALL THICKNESS NOT OVER 22 mm 10.88 in.)
It
---
4 r-
10 deg t 1 deg
10deg t l d e g
- 0 -
I
I
'\
(\ \
\
(0.75 20.06)
1.6 t0.8
(0.06 t0.03) (0.06 20.03)
[Note (1)l
(a) Welding End Detail for JointWithout Backing Ring (b) Welding End Detailfor Joint Using Split
Rectangular Backing Ring
\ \ I
I I
+0.25 - 0 +0.25 - 0
,J (+0.010 - 0) (+0.010 - 0)
I
13(0.5) min 1
(C) Welding End Detail forJoint UsingContinuous (dl Welding End Detail
for Joint Using Continuous
Rectangular Backing Ring Tapered Backing Ring
GENERAL NOTES:
(a) Broken lines denote maximum envelope for transitions from welding groove and root
face into body of components.
See Fig. 1 for details.
(b) See Section 5 for tolerances other than those givenin these sketches.
(c) Purchase order must specify contour of any backing ring to be used.
( d l Linear dimensions are in millimeters withinch values in Darentheses.
NOTES:
(1) Internal surface may be as-formed or machined for dimension 8 at root face. Contour within the envelope shall be in accordance
with Section 2.
(2) Intersections should be slightly rounded.
FIG. 3 WELD BEVEL DETAILS FOR WALL THICKNESS OVER 22 mm (0.88 in.)
(0.06 +0.03)
shall have 37'/2 deg ? 2!4 deg bevels or slightly
concave bevels. See Fig. 4.
GENERAL NOTES:
(c) Components having nominalwall thicknesses (a) This detail applies for gas tungsten arc welding (GTAW) of
over 10 mm (0.38 in.) to 25 mm (1.0 in.) inclusive the root pass where nominal wall thickness is over
shall have bevels as shown in Fig. 5. 3 m m (0.12 in.) t 3 10 m m (0.38in.) inclusive.
(d) Components having nominal wall thicknesses (b) Linear dimensions are in millimeters with inch values in
parentheses.
greater than 25 mm (1.0 in.) shall havebevelsas
shown in Fig. 6 .
FIG. 4 WELDBEVELDETAILSFOR GTAW
ROOT PASS
4 PREPARATION OF INSIDE DIAMETER OF [Wall Thickness Over 3 mm (0.12 in.)
WELDING END to 10 mm (0.38 in.), Inclusive]
4.1 General
Preparation of the inside diameter attheend of a and 6 are tabulated in Table 1 for DN 65 through 900
component shall be in accordance with one of the (NPS 21/, through 36).
following, as specified by the purchaser. Dimensions for other sizes and/or wall thicknesses
(a) Components to be welded without backing rings canbe determined by the following formulas:
shall meet the requirements of the standard or specifica-
tion for the component.
(b) Components to be welded using split or noncon- C =A - 0.79 - 1.75r - 0.25 mrn
tinuous backing rings shall be contoured with a cylindri-
cal surface atthe end as shown in Fig.2, sketch (b) (C = A - 0.031 - 1.75t - 0.010 in.)
andFig. 3, sketch (b). If the backingring contour is
other than rectangular, details mustbe furnished by
the purchaser.
(c) Components to be welded using solid or continu-
where
ous backing rings shall be contoured with a cylindrical A = nominal O.D. of pipe (see column 3 in
or tapered surface at the end asspecified by the Tables I and Al, taken from ASME
purchaser. End preparation is illustrated in Fig. 2, sketch B36. IOM)
(c) andFig.3, sketch (c) for rectangular ends and in 0.79
Fig. 2, sketch (d) and Fig. 3, sketch (d) for tapered ends. (0.031) = minus tolerance on O.D. of pipe, mm
(d) Components to beweldedusing consumable (in.), as covered by ASTM specifications
insert rings or GTAW root pass shall be contoured havingthemore restrictive requirements
with a cylindrical surface at the end as shown in Figs. suchas A 106, A 335, etc.
4, 5, and 6. 1.75 = minimalwall of 871/2% of nominalwall
(permitted by ASTM specification having
the more restrictive requirements such as
4.2 Dimension C A 106, A 335, etc.) multiplied by 2 to
Values for dimension C shown in Fig. 2, sketches convert into terms of diameter
(c) and (d); Fig. 3, sketches (c) and (d); and Figs. 5 t = nominal wall thickness of pipe, mm (in.)
-- 1 20 deg 22.5
deg
-- i2.5deg
20deg
i\ \
+- 0 to 2 (0.06)
5(0.19) R
--J
30 deg f0maxL??!!fl 5(0.19) min I +0.25
(4.010 'I
- 0.040)
- 1.02
--J 5(0.19) min
Type B
rLPe A
GENERAL NOTES:
(a) This detail applies for gas tungsten arc welding (GTAW) of the root pass where nominal wall thickness is over 10 mm (0.38in.) to
25 mm ( 1.0 in.) inclusive.
(b) Broken lines denote maximum envelope for transitions from welding groove and land into body of component. See Fig. 1 for details.
(c) See Section 5 for tolerances other than those given in these sketches.
(d) Linear dimensions are in millimeters with inch values in parentheses.
NOTE:
(1) Inside corners should be slightly rounded.
.
-1
\.
10 deg +1 dag -1 kldeg 10deg
'.
\
'
r
\
\ '3(0.12) \
\ \ + +0 to 2 (0.06)
20 deg k2.5 deg
20 deg 4 5 deg
19 t o 25
19 t o 25 (0.75 to 1.00)
(0.75 to 1.00)
f
1
Ir (+0.010-0.040) 5(0.19) rnin
--J ,J
GENERAL NOTES:
(a) This detail applies forgas tungsten arc welding (GTAW) of root pass where nominal wallthickness is greater than 25 rnrn (1.0 in.).
(b) Broken lines denote maximum envelope for transitions from welding groove and land into body of component. See Fig. 1 for details.
(c) See Section 5 for tolerances other than those givenin these sketches.
Id) Linear dimensions are in millimeters with inchvalues in parentheses.
NOTE:
(1) Inside corners should be slightly rounded
Wrought or
Nominal Schedule Fabricated Cast Steel
Pipe Size No. Components, Valves,
[Note
(DN) (1)l A [Note (111 A [Note (211 B C [Note (311 t
Wrought or
Nominal Schedule Fabricated Cast Steel
Pipe Size No. Components, Valves,
[Note
(DN) (111 A [Note (111 A [Note (211 B C [Note (311 t
300 323.8 329 289 292.17 17.48
100 323.8 329 281 285.24 21.44
120 323.8 329 273 278.31 25.40
140 323.8 329 266.5 272.75 28.58
160 323.8 329 257 264.45 33.32
Wrought or
Nominal Schedule Fabricated Cast Steel
Pipe Size No. Components, Valves,
[Note
(DNI (111 A [Note (111 A [Note (211 B C [Note (3J1 f
GENERAL NOTES:
(a) Dimensions are in millimeters.
(b) See Section 5 for tolerances.
NOTES:
(1) Letter designations signify:
(a) STD = standard wall thickness
(b) XS = extra-strong wall thickness
(c) XXS = double extra-strong wall thickness
(2)The diameters listed are not requirements. They are provided for the convenience of the user.
(3)Internal machining for continuous backing rings for sizes DN 50 and smaller is not contemplated. See para. 4.2 for C
dimension for sizes not listed.
10
ANNEX A
INCH TABLE
(This Annex is an integral part of ASME B16.25 and is placed after the main text for convenience.)
Wrought or
Nominal Schedule Fabricated Cast Steel
Pipe Size No. Components, Valves,
12
13
Wrought or
Nominal Schedule Fabricated Cast Steel
Pipe Size No. Components, Valves,
[Note
INPSI I1 I1 A [Note (1)1 A [Note (211 B C [Note (3I1 t
GENERAL NOTES:
(a) Dimensions are i n inches.
(b) See Section 5 for tolerances.
NOTES:
(1) Letter designations signify:
(a) STD = standard wall thickness
(b) XS = extra-strong wall thickness
(c) XXS = double extra-strong wall thickness
(2) The diameters listed are not requirements. They are provided for the convenience of the user.
(3) Internal machining for continuous backing rings for sizes NPS 2 and smaller is not contemplated. See para. 4.2 for C
dimension for sizes not listed.
14
The products manufactured in accordance with ASME manufacturers quality system program by an indepen-
B16.25 shall be produced under a quality system pro- dent organization shall be the responsibility of the
gram following the principles of an appropriate standard manufacturer. The detailed documentation demonstra-
fromthe I S 0 9000 series. A determination of the ting
program compliance shallbe available to
the
need for registration and/or certification of the product purchaser at the manufacturers facility. A written sum-
mary description of the program utilized by the product
manufacturer shall be available tothe purchaser upon
The series is also available from the American National Standards request. The product manufacturer is defined as the
Institute(ANSI) and theAmericanSocietyforQualityControl entity whose name or trademark appears on the product
(ASQC)asAmericanNationalStandardsthatare identified by a
prefix Q replacing the prefix ISO. Each standard of the series in accordance with the marking or identification require-
is listed underreferences. ments of ASME B16.25.
ANNEX C
REFERENCES
(This Annex is an integral part of ASME B16.25 and is placed after the main text for convenience.)
17