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PLAIN BEARING FAILURE
10. Manufacturing faults and Assembly Errors
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Manufacturing faults index
10.3 Incorrect drilling of oil feed hole
| Click on photograph to enlarge | |
  | Fatigue damage to journal bearing (a) in line with incorrectly positioned feed hole partially drilled in back of shell (b) |
| Main Characteristics | A small patch of fatigue damage adjacent to the oil hole. Photograph 'a'. Fatigue would be expected to occur at the position of maximum, not at the bottom of the bearing |
| Cause | Examination of the back of the bearing shell shows a partially drilled hole in line with the fatigue damage, Photograph 'b'. This was obviously a machining error that was discovered before the oil feed hole was completely drilled through. This has resulted in inadequate support of the white metal that has failed in fatigue. |
| Note | This was a main bearing from a reciprocating compressor, with sufficient alternating loading to cause the fatigue. |
| Possible Confusion with Other Types of Damage | While this is clearly a fatigue failure, the location of the fatigue patch suggests some abnormality. |
| Comment | The back of the bearing shell should always be examined, particularly in cases of abnormal damage. |