IOM/GK(P)/CONICAL ISSUE DATE: 10.11.2015
Page 68 LAST REV. DATE: 01.08.2019
Bearing temperature increases
19 20 21 22 31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 51 54 55 58
Motor will not start
14 22 60
Motor gets hot or burns out
14 22 27
28 40 43 50 55 56 57 58 59 60 61
Motor is difficult to start
14 22 27
28 45 46 50 58 59 60
CHECK POINTS
1. Suction pipe, foot valve choked.
2. Nominal diameter of suction line too small.
3. Suction pipe not sufficiently submerged.
4. Too many bends in the suction line.
5. Clearance around suction inlet not sufficient.
6. Shut off valve in the suction line in unfavourable position.
7. Incorrect layout of suction line (formation of air pockets).
8. Valve in the suction line not fully open.
9. Joints in the suction line not leak-proof.
10. Air leaking through the suction line and stuffing box, etc.
11. Suction lift too high.
12. Suction head too low (difference between pressure at suction connection
and vapor pressure too low).
13. Delivery liquid contains too much gas and/or air.
14. Delivery liquid too viscous.
15. Insufficient venting.
16. Number of revolutions too high.
17. Number of revolutions too low.
18. Incorrect direction of rotation (electric motor incorrectly connected, leads
of phases on the terminal block interchanged).
19. Impeller clogged.
20. Impeller damaged.
21. Casing rings worn out.
22. Separation of crystals from the flow of pumping liquid (falling below the
temperature limit/equilibrium temp).
23. Sealing liquid line obstructed.
24. Sealing liquid contaminated.
25. Mechanical seal / casing cover / shaft concentricity get damaged.
26. Sealing liquid omitted.
27. Mechanical seal faces damaged.
28. Mechanical seal locking plates are not removed.
29. Seal not suitable for operating conditions.
30. Mechanical seal throat bush (if applicable) got damaged.
31. Bearing worn out.
32. Specified oil level not maintained.
