Bearings in Compressors!

A typical case of a Quick Failure of bearings!
In an installation that was encountered and observed, a compressor bearing failed so early (within less than four months in continuous operation) after a restoration procedure. Many failure propositions were advanced by different engineers in maintenance and by the jobber, which included the following:
1.Bearings were not original.
2.There was lack of lubrication.
3.The bearing alignment was not correct.
4.There was lack of skill in assembling the bearing.
5.The bearing was not the correct one for the service.
6.The clearance was not correct.

The bearings were again replaced, and again the replacement bearings failed for the second time in less than one day operation. Replacement of bearings were again made for the third time, and the same thing happened. Noteworthy to consider was the fact that the cost of the bearings were substantial, because these were about six (6) inch diameter roller and ball bearings, with some thrust capability. In the end, the jobber was asked to verify the original bearing casing center, and it was learned that the work was subcontracted to a shop that may not have been able to find the original centers, due to the need to rebuild the casing or bearing housings, which were damaged during the first failure. In this connection, all efforts were directed by the jobber’s new shop service provider, to the restoration of the bearing alignment and centering back to the original installation.

The procedure of the OEM may not have been replicated locally the first time, to the extent that the bearing subsequently improved in its performance only, but continued to give a noisy operation and a non-stable air gap performance between air lobes (screws). In this regard, it is deemed high-time to bring the matter to the OEM shop for trade-in and replacement of a new service unit. Some OEM machineries and skills are not totally replicable by less qualified local shops . Hence, to save further inconvenience and uneconomical operation, it is advised that the OEM should be brought in. When local efforts fail so dismally after the first service restoration process, and several times thereafter, the recourse to the OEM becomes obvious and much more logical. Further local efforts may find the solution, but only at the expense of long term operational potential losses.
Written by: Sanoy C. Suerte, RME /MBM; http://www.linkedin.com/in/sannysuerte