Faults - KSB WKLn Installation & Operating Manual

Cause - Remedy 1)
1. The pump generates an excessively high differential pressure
- Reset the duty point
2. Excessively high back pressure
- Check the pump set for impurities
- Fit larger impeller(s)
- Increase speed (applies to turbine driven or I.C. engine driven pumps)
3. The pump and/or piping are incompletely vented or primed
- Vent or prime the pump and piping completely
4. Suction line or impeller(s) clogged
- Remove deposits in the pump and/or piping
5. Formation of air pockets in the piping
- Alter piping layout
- If necessary, fit a vent valve
6. Suction head too great/NPSH available too small
- Check liquid level in suction vessel
- Open isolating valve in suction line fully
- After suction line if necessary, if the friction losses in the suction line are excessive
- Check suction line strainers/suction aperture
8. Ingress of air through the stuffing box
- Sealing liquid passage is clogged; clean it 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 phases of the power supply cable
10. Rotational speed is too low
- 2)
- Increase speed
11. Excessive wear of the pump internals
- Replace worn components with new ones
12. Pump back pressure is lower than specified in the purchase order
- Accurately set the duty point
- In case of persistent overloading, trim the impeller(s) if necessary
- 2)
13. Specific gravity or viscosity of the fluid pumped is higher than specified in the purchase order
- 2)
15. Excessive rotational speed
- Reduce speed
- 2)
16. Tie bolts/ O-rings
- Tighten up the bolts
- Fit new O-rings
17. Worn shaft seal
- Check condition of shaft seal and renew it if necessary
- Check flushing liquid or sealing liquid pressure
18. Grooving, score marks or roughness on shaft protecting sleeve/shaft sleeve surface
- Fit new shaft protecting sleeve/shaft sleeve
- Fit new shaft seal
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6.9 Faults

2)
WKLn