Cashco SCV-30 - Manual (Page 8)

IOM-SCV-30 8
Possible Cause Remedy
A. Ruptured plug diaphragm. A. Remove body, disassemble, remove old dia-
phragm. Install new diaphragm, reassemble and
reinstall.
VII.TROUBLE SHOOTING GUIDE
SECTION VII
Possible Cause Remedy
A. Sizing data not correct; valve undersized. A1.
A2.
Check actual pressures, temperature, and fl ow
rates against the variables used for sizing. Recal-
culate Cv Required.
Replace unit with larger body size.
B. Obstruction at inlet. B. Remove valve from line and inspect for something
causing blockage.
1. Unit can not pass enough fl ow.
Possible Cause Remedy
A. Excess pressure levels. A. Check actual pressures against those indicated
in technical bulletin. Reduce pressures as neces-
sary.
B. Loose clamp. B. Remove valve from service. Disassemble and
clean. Reassemble and properly tighten all
clamps at reinstallation.
C. Excessive piping stress. C. Place hanger on control valve unit.
D. Improper pipe alignment. D. Redo piping properly.
2. Valve body leaking at clamped end or bonnet connection joints.
3. Fluid leakage at bonnet vent or at bonnet/stem guide zone.