Alfa Laval SRC PN10, 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 section
4.2 Fault finding
Problem Cause/result
Repair
The valve plug jerks The lealings seize Lubricate:
-
O-rings (2)
- O-ring (5) and the inside of cylinder (3)
- Lip seal (14)
Product leakage
at stem and/or clamp
- Worn/product affected lip seal (14) and/or
seal ring (17)
- Replace the seal
- Replace with a seal of a
different rubber grade
Product leakage
(closed valve) - Worn/product affected
- Loose plug parts (vibrations)
- Product deposits on the seat and/or plug
- Replace the seal ring
- Replace with a seal of a different rubber
grade
- Tighten the loose parts
- Frequent cleaning
Product leakage
(too high pressure or too
small actuator) - Worn actuator O-rings
- Too small actuator or actuator spring
- Replace the O-rings
- Replace with a larger actuator
(for valve sizes DN/OD38-63.5 mm/
DN40-65)
- Fit a stronger spring (for valve sizes
DN/OD38-63.5 mm/DN40-65)
- Use auxiliary air on the spring
side (NOT-element)
Water hammer The flow direction is the same as the closing
direction - The flow direction should be against the
closing direction
- Fit a damper on the valve (optional extra)
- Use auxiliary air on the spring side
(NOT-element)
The valve does not open/close - Faulty clip assembly (11)
- The pressure on the plug plug is too high
- Replace the clip assembly
- Reduce the pressure plug is too high
- Fit stronger spring/larger actuator (for
valve sizes DN/OD38-63.5 mm/ DN40-65)
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