172-65260m-05 (S-COS/S-COSR Pressure Reducing Valve) 27 Oct 2008
13
Adjustment
The S-COS/S-COSR pressure reducing valve should be properly adjusted for
protection of the steam equipment against water hammer.
1. It is necessary to blow down all pipe lines thoroughly. The blowdown is especially
important if the line is new or has been shut down for a long period of time.
Take particular care to ensure that matter such as condensate and dirt does not
remain inside the steam equipment.
(Stay clear of any pressurized blow-out from the safety valve.)
2. Make sure that the shut-off valve and the bypass valve located upstream and
downstream of the pressure reducing valve are completely closed.
3. Loosen the locknut and turn the adjustment screw counterclockwise to reduce
tension on the coil spring.
4. Slowly, fully open the shut-off valve at the inlet of the pressure reducing valve.
Allow sufficient time for condensate remaining at the inlet of the pressure
reducing valve to be discharged.
5. Slightly open the shut-off valve at the outlet of the pressure reducing valve.
6. Turn the adjustment screw clockwise until the desired outlet pressure is obtained.
Wait several minutes.
7. Slowly, fully open the shut-off valve at the outlet of the pressure reducing valve.
8. After adjustment, retighten the locknut.
9. When shutting down the system, always close the outlet shut-off valve first and
then the inlet valve.
Loosen the locknut
Pull up the adjustment screw
Decrease Pressure
Counterclockwise
Clockwise
Counterclockwise
Increase Pressure
