Operating Procedure; Precautions During Operation; Adjustment Procedures - Yoshitake GP-1200 Installation And Operation Manual

7. Operating Procedure

7.1 Precautions during operation

 Warning
(1) Do not touch the valve directly with bare hands.
※Doing so may result in burns.
(2) Before flow the steam in pipe line, make sure steam can flow without any dangerous at
the end of pipe line and pipe line is connected tightly.
※In case steam blow off, it may result in burns.
 Caution
(1)Close the stop valves before and after the pressure reducing valve, and remove all
foreign matter and scales via the by-pass line before operation. And, open each stop
valve slowly.
※ F ailure to do so may prevent the valve from functioning correctly. And, It may cause
hunting, water hammer, etc., resulting in damage to the valve and other equipment
when the stop valve is opened quickly.
(2)Secondary pressure at by-pass line must be lower than set pressure.
※ S afety valve blows in case secondary pressure at by-pass line becomes higher than
set pressure.
(3)When adjusting pressure, slowly increase loading air pressure.
※ I ncorrect adjustment may cause hunting, water hammer, etc., resulting in damage to
the valve and other equipment.
(4)Remove condensate completely from the line, and close the stop valves before and
after the valve when not using it for long periods of times.
※Rust generated in the valves and lines may cause malfunction.

7.2 Adjustment procedures

Follow the steps below, and slowly turn the adjusting screw to set pressure. Incorrect adjustment may
cause hunting, water hammer, etc., resulting in damage to the valve and other equipment.
（1） Close the stop valve at inlet and outlet side of the pressure reducing valve, and taking sufficient
time not to blow the safety valve, blow off the fluid to remove foreign matter via the by-pass
line. After blowing, close the by-pass line stop valve.
（2） Slowly open the stop valve at the inlet side of the pressure reducing valve, and adjust the travel of
the stop valve at the outlet side of the pressure reducing valve so that a little fluid flows.
（3） Set operating air pressure to no-pressure. And slowly increase the operating pressure until the
desired pressure is reached while observing the pressure gauge on the outlet side.
（4） Slowly open the stop valve at the outlet of the pressure reducing valve, and readjust the desired
pressure.
（5） After adjustment, secure the handle of the standard unit's pressure reducing valve.
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■EPDT-101■