KSB CPK - Troubleshooting Guide

CPK
11
- If necessary fit a vent valve.
6. NPSH available is too low (on positive suction head
installation)
- Check liquid level in suction vessel.
- Open isolating valve in suction line fully.
- Install a different suction line if necessary, if the
friction losses in the suction line are excessive.
- Check the suction line strainer.
7. Excessively high suction lift
- Clean out suction strainer basket and suction piping.
- Check liquid level in the pit.
- Alter the suction line.
8. Entrainment of air through the stuffing box.
- Sealing liquid passages are clogged; clean them
out if necessary, arrange a sealing liquid supply
from an outside source, or increase sealing liquid
pressure.
- Fit a new shaft seal.
9. Reverse rotation.
- Change over two of the phase leads of the power
supply cable.
10. Rotational speed is too low
2) 3)
- Increase rotational speed
- Increase voltage of power supply
11. Excessive wear of the pump internals
- Replace worn components by new ones.
12. Pump back pressure is lower than specified in the
purchase order.
- Adjust duty point accurately by means of the isolating
valve in the discharge line.
- In case of persistent overloading, trim the impeller
if necessary
2)
13. Specific gravity or viscosity of the fluid pumped is
higher than that specified in the purchase order
2)
14. Stuffing box gland tightened excessively or askew
- Adjust the gland as required.
15. Excessive rotational speed
- Reduce speed (applies to turbine or I.C. engine
driven pumps
2) 3)
16. Worn shaft seal
- Check condition of shaft seal and renew it if
necessary.
- Check flushing liquid or sealing liquid pressure.
17. Grooving score marks or roughness on shaft protection
sleeve surface.
- Fit a new shaft protection sleeve
18. Lack of cooling liquid or fouled and clogged liquid
compartment.
- Increase the flow of cooling liquid
- Clean out the cooling compartment
- Clean the cooling liquid itself.
19. Stuffing box gland, and cover or seal cover incorrectly
tightened, wrong type of packing material used.
- Remedy the fault.
20. The pump runs rough
- Correct the suction conditions
- Check alignment of pumping set and realign if
necessary
- Re-balance the pump rotor dynamically
- Increase the suction pressure at pump suction
nozzle.
21. Pumping set misaligned
- Check alignment at coupling and realign the set if
necessary
22. The pump is warped
- Check piping connections and pump fixing bolts.
23. Excessive axial thrust
2)
- Clean out balance holes in impeller
- Fit new casing wear ring.
24. Too much or too little lubricant or unsuitable lubricant
quality.
- Top up lubricant, reduce quantity of lubricant or change
lubricant quality.
25. The prescribed coupling gap has not been maintained
- Restore correct coupling gap in accordance with
the data on the foundation drawing.
26. Operating voltage is too low.
- Rectify.
27. The motor is running on two phases only.
- Replace the defective fuses.
- Check the cable connections.
28. The connecting bolts are slack.
- Tighten the bolts.
- Fit new gaskets.
29. The rotor is out of balance
- Clean the rotor
- Re-balance the rotor dynamically
30. Defective bearings
- Fit new bearings.
31. Insufficient rate of flow
- Increase the minimum rate of flow.
32. Faults in the circulation liquid supply
- Increase the cross section of the circulation liquid
line.
1) The pump should be made pressurless before attempting to remedy faults
concerning parts exposed to pressure
2) Please refer to KSB
3) This fault can be also be remedied by altering the impeller diameter.