BODY SIZE DIAPHRAGM 
MATERIAL
MAXIMUM OPERATING 
INLET PRESSURE(4)
MAXIMUM OPERATING 
DIFFERENTIAL PRESSURE(3)(4)
MAXIMUM EMERGENCY INLET 
AND DIFFERENTIAL PRESSURE MAIN SPRING COLOR
DN NPS bar psig bar psig bar d psid
25 1
17E68 Nitrile (NBR) 20.7 300 20.7 300 20.7 300 Black and Yellow
17E97 Nitrile (NBR) 20.7 300 20.7 300 20.7 300 Black and Yellow
41.4 600 41.4 600 41.4 600 Black and White(2)
17E88 
Fluorocarbon (FKM)
20.7 300 20.7 300 20.7 300 Black and Yellow
41.4 600 34 500 41.4 600 Black and White(2)
50 2
17E68 Nitrile (NBR) 20.7 300 20.7 300 20.7 300 Green and White
17E97 Nitrile (NBR) 20.7 300 20.7 300 20.7 300 Green and White
41.4 600 41.4 600 41.4 600 Purple(2)
17E88 
Fluorocarbon (FKM)
20.7 300 20.7 300 20.7 300 Green and White
41.4 600 34 500 41.4 600 Purple(2)
80 3
17E68 Nitrile (NBR) 20.7 300 20.7 300 20.7 300 Light Blue and White
17E97 Nitrile (NBR) 20.7 300 20.7 300 20.7 300 Light Blue and White
41.4 600 41.4 600 41.4 600 Black(2)
17E88 
Fluorocarbon (FKM)
20.7 300 20.7 300 20.7 300 Light Blue and White
41.4 600 34 500 41.4 600 Black(2)
100 4
17E68 Nitrile (NBR) 20.7 300 20.7 300 20.7 300 Green and White
17E97 Nitrile (NBR) 20.7 300 20.7 300 20.7 300 Green and White
41.4 600 41.4 600 41.4 600 Red(2)
17E88 
Fluorocarbon (FKM)
20.7 300 20.7 300 20.7 300 Green and White
41.4 600 34 500 41.4 600 Red(2)
1. See Table 1 for main valve structural design ratings and Table 2 for pilot ratings.
2. The black and white, purple, black and red springs are only recommended for applications where the maximum inlet pressure can exceed 20.7 bar / 300 psig.
3. Maximum differential pressures may be lower for applications where cavitation may be present.
4.  These are recommendations that provide the best regulator performance for a typical application. Please contact your local Sales Ofce for further information if a deviation from the 
standard recommendations are required.
Table 5. Main Valve Maximum Pressure Ratings, Diaphragm Selection Information and Main Spring Selection(1)
Overpressure Protection
The recommended pressure limitations are 
stamped on the regulator nameplate. Some type of 
overpressure protection is needed if the actual inlet 
pressure exceeds the maximum operating outlet 
pressure rating. Overpressure protection should 
also be provided if the regulator inlet pressure 
is greater than the safe working pressure of the 
downstream equipment.
Regulator operation below the maximum pressure 
limitations does not preclude the possibility of 
damage from external sources or debris in the line. 
The regulator should be inspected for damage after 
any overpressure condition.
Startup
The regulator is factory set at approximately 
the midpoint of the spring range or the pressure 
requested, so an initial adjustment may be required 
to give the desired results. With proper installation 
completed and relief valves properly adjusted, 
slowly open the upstream and downstream 
shutoff valves.
Adjustment
To change the outlet pressure, loosen the jam nut 
and turn the adjusting screw clockwise to increase 
outlet pressure or counterclockwise to decrease it. 
Monitor the outlet pressure with a test gauge during 
the adjustment. Tighten the jam nut to maintain the 
desired setting.
Taking Out of Service (Shutdown)
WARNING
To avoid personal injury resulting from 
sudden release of pressure, isolate the 
regulator from all pressure before 
attempting disassembly.
Table 6. Main Valve Minimum Differential Pressure(1)
MAIN VALVE BODY SIZE
MAIN SPRING PART NUMBER AND COLOR DIAPHRAGM MATERIAL
MINIMUM DIFFERENTIAL, PERCENT OF CAPACITY
For 90% Capacity For 100% Capacity
DN In. bar d psid bar d psid
25 1 GE12727X022, Black and Yellow 17E68 and 17E88 2.1 30 2.1 30
17E97 2.5 35 2.5 35
19B2401X022, Black and White 17E88 and 17E97 3.0 43 3.0 43
50 2 18B2126X022, Green and White 17E68 and 17E88 1.2 18 1.3 19
17E97 1.7 24 1.7 24
18B5955X012, Red 17E88 and 17E97 2.0 29 2.1 31
80 3 19B0781X022, Light Blue and White 17E68 and 17E88 1.5 21 1.9 28
17E97 1.6 23 1.6 23
19B0782X022, Black and White 17E88 and 17E97 2.2 32 2.6 38
100 40 18B8501X022, Green and White 17E68 and 17E88 1.1 16 2.1 30
17E97 1.1 16 2.3 34
18B8502X022, Red and White 17E88 and 17E97 1.5 21 2.8 40
1. See Table 1 for Type LR125 main valve structural design ratings and Table 2 for pilot rating.