Alfa Laval Unique RV-ST, Instruction Manual

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4 Operation
Pay attention to possible faults. Study the instructions carefully.
The items refer to the parts list and service kits (chapter 7 Parts list and service kits).
4.2 Troubleshooting
NOTE!
Study the maintenance instructions carefully before replacing worn parts. See chapter 5.1 General maintenance.
Problem Cause/result Repair
External product leakage
Worn or product affected lip seal and/or
O-ring
- Replace the seals
- Replace with seals of a different rubber
grade
Internal product leakage - Worn or product affected plug seal - Replace the seal
- Replace with a seal of a different
rubber grade
- Product deposits on the seat and/or
plug
- Frequent cleaning
- The product pressure on the plug is
too high - Reduce product pressure
Water hammer The flow direction is the same as the
closing direction - The flow direction should be against
the closing direction
The valve does not open/close - The pressure on the plug is too high - Reduce the product pressure
Deviation in the flow regulation - Mechanical parts have come loose
(vibrations) - Tighten and adjust
Actuator does not regulate - No air Check air supply
- Actuator errors - Return the actuator to the supplier
- Positioner errors - Check positioner (see positioner
instruction)
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