BR-G-REG-1329-0313-01-A*

Model 122 Industrial Combustion Regulators

Construction and Design Features

Model 122 Industrial Combustion Regulators Periodic Inspection

For an unbeatable combination of capacity, performance and Regulators are pressure control devices with numerous moving
economy, install the Sensus Model 122 industrial combustion- parts subject to wear that is dependent upon particular operating
type gas pressure regulator. conditions. To assure continuous satisfactory operation, a periodic
inspection schedule must be adhered to with the frequency of
Streamlined body passages provide large capacity. Carefully
inspection determined by the severity of service and applicable
engineered internal sensing produces accurate pressure control
laws and regulations.
without an external control line. And, just in case a particular
application necessitates one, a handy tap on the 122 makes
connection into an external control line a simple matter. Maximum Emergency Pressures
Diaphragm cases are high strength, corrosion resistant die-cast The maximum inlet pressure that a Model 122 regulator may be
aluminum alloy. This makes a better looking regulator at a better subjected to under abnormal conditions without causing internal
price. In addition, on 1" through 2½" sizes a large area double damage is 20 psi.
acting damper in the vent assures fast speed of response while The maximum pressure the diaphragm may be subjected to
maintaining stability, which is just the thing for those troublesome under abnormal conditions without causing internal damage is
“snap-acting" loads. set-point plus 2 psi. Set-point is defined as the outlet pressure
Soft seats plus a precision machined “knife-edge" orifice provide that a regulator is adjusted to deliver.
positive tight shutoff, and the orifice is removable. If either of the above limits is exceeded then the regulator must
be taken out of service and inspected. Damaged or otherwise
Maximum Inlet Pressure Is 15 psig unsatisfactory parts must be repaired or replaced before returning
the regulator to service.
Outlet pressure is easily adjusted throughout a range of inches
w.c. to 2 psig. The springs are color coded for easy identification. The maximum pressure that can be safely contained by the
diaphragm case on a Model 122 regulator is 5 psi. Safely
Temperature Limits contained means no leakage as well as no bursting.
Model 122 regulators can be used for temperatures from -20°F to Before using any of the above data, make sure this entire section
+150°F. is clearly understood.

Buried Service
These regulators are designed for above ground or vault
installations and are not recommended for direct earth burial.

Outlet Pressure Ranges and Springs – Standard Regulator

OUTLET NOMINAL
SPRING SPRING
SIZE PRESSURE DIAPHRAGM
COLOR PART NUMBER
RANGE SIZE
Blue-black 143-82-021-01 (main spring)
1½" to 3½" w.c.
Black 143-41-021-00 (counter spring)
Green-black 143-82-021-02 (main spring)
1½" to 12" w.c.
Black 143-41-021-00 (counter spring)
1" and 1¼"
8"
Model 122-8 3½" to 6½" w.c. Red-black 143-82-021-00
5" to 8½" w.c. Blue-black 143-82-021-01
6" to 14" w.c. Green-black 143-82-021-02
12" to 28" w.c. Green 143-16-021-05
1 psi to 2 psi Orange 143-16-021-06
Red 143-16-021-03 (main spring)
1½" to 3½" w.c.
Red-black 121-10-021-50 (counter spring)
Maroon 121-42-021-00 (main spring)
1½" to 12" w.c.
Red-black 121-10-021-50 (counter spring)
1½", 2" and 2½"
3½" to 6½" w.c. Red 143-16-021-03 12"
Model 122-12
5" to 8½" w.c. Blue 143-16-021-04
6" to 14" w.c. Green 143-16-021-05
12" to 28" w.c. Orange 143-16-021-06
1 psi to 2 psi Black 143-16-021-07
½ psi to 2 psi Cadmium 143-16-021-08

*This document replaces R-1329 Rev. 10

Model 122 Industrial Combustion Regulators Construction and Design Features

122-12 Standard Regulator with Internal Control

(See IN-G-REG-1329-0312-01-A for Other Variations)

OPTIONAL
TRAVEL
INDICATOR2

COLOR DOUBLE ACTING2

CODED VENT DAMPER
SPRINGS • Assures fast response
plus stable operation

OPTIONAL
EXTERNAL
CONTROL
LINE

DIE CAST ALUMINUM ALLOY INTERNAL CONTROL TUBE

DIAPHRAGM CASE • Engineered for accurate
• High Strength pressure control
• Light Weight
• Corrosion Resistant

OUTLET PRESSURES
INLET PRESSURES 1½" w.c. to 2 psi
to 15 psi

REMOVABLE ORIFICE1 CAST IRON BODY

• Precision knife-edge plus CDF1329-005 (ASTM A126, 2"/2½" body shown)
molded soft seats assure • Strong, durable, maximum
positive tight shutoff pipe thread reusability

Construction shown is for 1½", 2" and 2½" pipe sizes.

1

Orifice in ¾", 1" and 1¼" pipe size is screwed-in.

2
Applies to 1", 1¼", 1½", 2" and 2½" pipe sizes.

2
 Model 122 Industrial Combustion Regulators Construction and Design Features

Typical Performance Curves

Pressure label for each curve is INLET PRESSURE.

11.0
1" – 122-8 Regulator (Blue-Black Spring)
9.0

7.0
5 psi 10 psi 15 psi

5.0
9" w.c. 14" w.c. 1 psi 2 psi 3 psi

3.0
0 2 4 6 8 10 12 14 16 18 20
CDF1329-010

11.0
1¼" – 122-8 Regulator (Blue-Black Spring)
9.0

15 psi
7.0
10 psi
5 psi
5.0
9" w.c. 14" w.c. 1 psi 2 psi 3 psi

3.0
OUTLET PRESSURE: Inches Water Column ("w.c.)

0 2 4 6 8 10 12 14 16 18 20
CDF1329-015

11.0
1½" – 122-12 Regulator (Blue Spring)
9.0

7.0 15 psi

10 psi
5.0
9" w.c. 14" w.c. 1 psi 2 psi 3 psi 5 psi

3.0
0 2 4 6 8 10 12 14 16 18 20
0
CDF1329-020

11.0
2" – 122-12 Regulator (Blue Spring)
15 psi
9.0
10 psi
7.0

2 psi 3 psi 5 psi

5.0
9" w.c. 14" w.c. 1 psi

3.0
2 6 10 14 18 22 26 30 34 38
CDF1329-025

11.0
2½" – 122-12 Regulator (Blue Spring)
15 psi
9.0

10 psi
7.0

5.0
9" w.c. 14" w.c. 1 psi 2 psi 3 psi 5 psi

3.0
0 5 10 15 20 25 30 35 40 45 50
CDF1329-030

FLOW in 1000 scfh natural gas (0.6 Specific Gravity – 14.65 psia – 60°F)

3
Model 122 Industrial Combustion Regulators Construction and Design Features

Capacity in SCFH of Natural Gas (0.6 Specific Gravity – 14.65 psia – 60°F)
SET POINT SET POINT SET POINT SET POINT SET POINT SET POINT
5" w.c. 7" w.c. 11" w.c. 18" 28" w.c. 2 psi
INLET REGULATOR SIZE
PRESSURE RED/BLACK BLUE/BLACK GREEN/BLACK GREEN GREEN ORANGE AND MODEL
SPRING SPRING SPRING SPRING SPRING SPRING
1" w.c. DROOP 1" w.c. DROOP 2" w.c. DROOP 2" w.c. droop 3" w.c. DROOP ¼" psi DROOP
8" w.c. 1550 1000 – – – –
14" w.c. 2500 2300 2000 – – –
1 psi 4200 4000 3600 2500 – –
2 psi 5700 5500 5300 4000 4500 – 1"
3 psi 7300 7000 6000 4900 5200 4000 Model 122-8

5 psi 8000 8000 8400 7800 8000 7500

10 psi 9000 9500 10000 9500 9700 9000
15 psi 9000 9500 11000 11500 11500 11000
8" w.c. 2000 15000 – – – –
14" w.c. 3500 3000 2200 – – –
1 psi 5000 4800 4000 3600 – –
2 psi 7300 7000 6400 5700 6000 – 1¼"
3 psi 9000 8700 8000 6900 7200 6300 Model 122-8

5 psi 10000 9800 9500 8800 9100 8100

10 psi 15000 15700 15200 14500 14900 13800
15 psi 15000 15700 15800 15000 15000 14000

SET POINT SET POINT SET POINT SET POINT SET POINT SET POINT
5" w.c. 7" w.c. 11" w.c. 18" w.c. 28" w.c. 2 psi
INLET REGULATOR SIZE
PRESSURE ORANGE ORANGE AND MODEL
RED SPRING BLUE SPRING GREEN SPRING BLACK SPRING
SPRING SPRING
1" w.c. DROOP 1" w.c. DROOP 2" w.c. DROOP ¼" psi DROOP
2" w.c. DROOP 3" w.c. DROOP
8" w.c. 4000 3000 – – – –
14" w.c 4900 4500 3700 – – –
1 psi 6600 6500 6000 5750 – –
2 psi 10500 10000 9800 9000 9500 – 1½"
3 psi 12000 12000 11100 10000 10500 8900 Model 122-12

5 psi 14500 14500 13900 12000 12700 10000

10 psi 16000 16000 15000 13500 14000 12700
15 psi 18000 18000 19000 19000 20000 18000
8" w.c. 5000 4000 – – – –
14" w.c. 8800 8000 6600 – – –
1 psi 12200 12000 11500 10700 – –
2 psi 18200 18000 17300 16500 16900 – 2"
3 psi 25000 25000 24000 22300 23000 18000 Model 122-12

5 psi 32000 32000 30000 28100 29000 27400

10 psi 38000 38000 35000 32200 33000 30000
15 psi 38000 38000 40000 39000 40000 36000
8" w.c. 5500 4500 – – – –
14" w.c. 9600 9000 7300 – – –
1 psi 13600 13400 12100 11300 – –
2 psi 20700 20000 19200 18200 18800 – 2½"
3 psi 27000 27000 26500 24900 25400 20000 Model 122-12

5 psi 35000 35000 32000 30200 31000 29000

10 psi 42000 42000 39000 36000 37000 33000
15 psi 48000 48000 48000 42000 45000 39900
NOTE: The above performance data is based on normal testing at 70°F flowing temperature.
Changes in performance can occur at extreme low flowing temperatures.

4
Model 122 Industrial Combustion Regulators Construction and Design Features

Overpressurization Protection Other Gases

Protect the downstream piping system and the regulator’s low Standard Model 122 regulators are most widely used on natural
pressure chambers against overpressurization due to possible gas. However, they perform equally well on LP gas, nitrogen, dry
regulator malfunction or failure to achieve complete lock up. CO2, and air.
The allowable outlet pressure is the lowest of the maximum For capacities, multiply the table values on page 4 by the
pressures permitted by federal codes, state codes, Sensus following correction factors:
Metering Systems IN-G-REG-1498, or other applicable
standards. Type of Gas Correction Factor

The method of protection can be a relief valve, monitor regulator, Air (Specific Gravity 1.0) 0.77
shutoff device, or similar mechanism. Propane (Specific Gravity 1.53) 0.63
1350 BTU Propane-Air Mix (Specific Gravity 1.20) 0.71
Materials of Construction
Nitrogen (Specific Gravity 0.97) 0.79
Body .......................................................................Cast Iron
Diaphragm Case ........................... Die Cast Aluminum Alloy Dry Carbon Dioxide (Specific Gravity 1.52) 0.63
Stem Bushing and Plate .................................... Plated Steel For other non-corrosive gases, use the following formula:
Main and Seal Diaphragms ...............................Buna-N with
(Vitron Not Available) Nylon Fabric Insert
Orifice ........................... Cast Iron (1½" and 2½" Model 122)
CORRECTION FACTOR = √ 0.60
Specific gravity of the gas

Orifice ....................................Brass (1" and 1¼" Model 122) For use with gases not listed above, please contact your Sensus
Valve .................Plated Steel with Molded Buna-N Soft Seat representative or industrial distributor for recommendations.
Stem .................................................................. Plated Steel
Diaphragm Pans, Collars and Washers ............ Plated Steel
O-Rings and Tetra Seals .......................................... Buna-N CAUTION
Adjustment Spring Button........................... Zinc Die Casting
It is the user’s responsibility to assure that all residential
(1" and 2½" Model 122)
service regulator vents and/or vent lines exhaust to a
Seal Cap, 243-8HP.......... Zinc Die Casting (1" through 2½")
non-hazardous location away from any potential sources of
ignition. Refer to Sensus Bulletin IN-G-REG-1329 for more
Full Open Capacity detailed information.
Capacity of the Model 122 in the wide-open position can be
calculated using the following formula and K factors: 122 Variations
1. Q = K√ Po(Pi – Po) The following variations of the Model 122 are also available:
Q = Full open capacity in SCFH of 0.6 specific gravity Atmospheric Regulator/Zero Governor
natural gas).
All pipe sizes through 2½".
Pi = Absolute inlet pressure (psia)
Po = Absolute outlet pressure (psia) Set-point pressures:
-1" w.c. to +1½" w.c .................. (1" through 2½" Model 122)
2. K Factors =
Differential Regulator
1" Model 122-8 ...................... K = 1400
1¼" Model 122-8 ................... K = 1750 All pipe sizes through 2½".
1½" Model 122-12 ................. K = 2750
Set points to maximum differential of 1 psi.
2" Model 122-12 .................... K = 4750
2½" Model 122-12 ................. K = 5250 Back Pressure Regulator/Relief Valve
Remember, at the above full open capacities the droop is All pipe sizes through 2½".
significantly greater than specified in the capacity tables. Set-point pressures:
When checking 122 regulator capacity to provide adequate 3" w.c. to 2 psi.............................. (1" and 1¼" Model 122-8)
relief valve capacity, use the full open capacity. Do not use 122 3" w.c. to 1¾" psi .................... (1½" and 2½" Model 122-12)
capacity from the tables. For more complete information refer to IN-G-REG-1329. For other
variations or special applications, please contact your Sensus
Representative or industrial distributor.

Larger Sizes
The 122 is manufactured in 1" through 2½" pipe sizes only. For
larger sizes, see the 3" and 4" Model 121.

5
Model 122 Industrial Combustion Regulators Construction and Design Features

Metrication How to Order

Use the following for metric conversions: Specify:
1. Model number
std. meters3/hr. x 35.31 = std. ft.3/hr. (SCFH)
std. ft.3/hr. (SCFH) x 0.0283 = std. meters3/hr. 2. Pipe size

kilograms/centimeter²(kg/cm²) x 14.22 = psig 3. Inlet pressure

psig x 0.0703 = kilograms/centimeter²(kg/cm²) 4. Outlet pressure
kilopascals (kPa) x 0.145 = psig 5. Capacity required, SCFH
psig x 6.90 = kilopascals (kPa)
6. Kind of gas (natural gas, propane, air, etc.)
bars x 14.50 = psig
psig x 0.69 = bars
millimeters water (mm H2O) x .0394 = in. w.c. CAUTION
in. w.c. x 25.4 = millimeters water (mm H2O) Turn gas on very slowly. If an outlet stop valve is used, it
millimeters mercury (mm Hg) x 0.535 = in. w.c. should be opened first. Do not overload the diaphragm with
in. w.c. x 1.868 = millimeters mercury (mm Hg) a sudden surge of inlet pressure. Monitor the outlet pressure
during start-up to prevent an outlet pressure overload.

Dimensions

A (Diameter)

Vent Outlet
1" NPT

B
F
Optional Inlet and Outlet
Taps ¼" NPT

C Optional Control Line

Connection ¼" NPT

D CDF1329-035

SHPG.
A B C D E F
WT.
1" NPT 10¼" 115⁄8" 17⁄8" 5¾" 2½" 37⁄16" 15 lbs.
1¼" NPT 10¼" 115⁄8" 17⁄8" 5¾" 2½" 37⁄16" 15 lbs.
1½" NPT 14" 13" 2 ⁄ 8"
3
7½" 3 ⁄16"
15
3 ⁄16"
9
28 lbs.
2" NPT 14" 13" 23⁄8" 7½" 315⁄16" 39⁄16" 28 lbs.
2½" NPT 14" 13" 2 ⁄ 8"
3
8¼" 3 ⁄16"
15
3 ⁄16"
9
30 lbs.

6
Model 122
NameIndustrial
and InfoCombustion Regulators Construction and Design Features

Notes:

7
BR-G-REG-1329-0313-01-A

Model 122 Industrial Combustion Regulators

Construction and Design Features

Authorized Distributor:

All products purchased and services performed are subject to Sensus’ terms of sale, available at either http://na.sensus.com/TC/TermsConditions.pdf or 1-800-METER-IT. Sensus reserves the right to modify
these terms and conditions in its own discretion without notice to the customer.
This document is for informational purposes only, and SENSUS MAKES NO EXPRESS WARRANTIES IN THIS DOCUMENT. FURTHERMORE, THERE ARE NO IMPLIED WARRANTIES, INCLUDING
WITHOUT LIMITATION, WARRANTIES AS TO FITNESS FOR A PARTICULAR PURPOSE AND MERCHANTABILITY. ANY USE OF THE PRODUCTS THAT IS NOT SPECIFICALLY PERMITTED HEREIN
IS PROHIBITED. © 2013 Sensus.

805 Liberty Boulevard For more information, visit us at sensus.com/gas

DuBois, PA 15801
1-800-375-8875