INOXPA PHARMAVALVE, Installation, Service & Maintenance Manual

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12 ED. 2009/09 /
5. Operating problems: Causes and
solutions
PROBLEM CAUSE/EFFECT SOLUTION
THE MOVEMENT OF
THE VALVE
DIAPHRAGM IS
UNSTEADY
The diaphragm or guide bushing have become worn,
deteriorated, or blocked up.
• Replace the diaphragm.
• Replace the diaphragm with one
of a different material and more
appropriate to the product.
• Lubricate with soapy water or
lubricant compatible with the
material of the diaphragm and
with the product.
Insufficient air pressure.
• Increase the compressed air
pressure.
INTERNAL LEAK OF
THE PRODUCT
(CLOSED VALVE)
Normal wear of the diaphragm.
• Replace the diaphragm.
Premature
wear of the
diaphragm.
Diaphragm worn or damaged by the fluid.
Excessive pressure in the line.
Working temperature too high
Loss of water tightness (vibration).
• Replace the diaphragm with one
of a different material and more
appropriate to the product.
•
Tighten any loose components.
• Clean frequently.
• In actuators NO and A/A, reduce
the air pressure.
Backpressure
• Increase the compressed air
pressure.
• Replace the actuator with a dual
effect one.
•
Reduce the line pressure.
LEAK IN LEAK
DETECTOR
Broken diaphragm
• Replace the diaphragm
VALVE DOES NOT
OPEN/CLOSE
The diaphragm is jammed
The diaphragm is not properly fitted in the actuator
Incorrect fluid flow, combined with high fluid pressure.
Actuator broken.
• Inspect the diaphragm and
replace if necessary.
• Fit correctly. Depending on
whether the diaphragm is fitted by
pressing on or screwing on to the
shaft.
• Change direction of the fluid and
lower the pressure.
• Replace the actuator
HYDRAULIC SHOCK The valve closes too fast.
• Adjust the closing speed of the
actuator (with a flow regulator).
THE ACTUATOR
LOSES AIR
Actuator gaskets worn • Replace the actuator