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Buffing/Polishing Vibration Monitoring Probe Tracks (4140 shafts)

We work in the maintenance of rotating equipment, which are often monitored for vibration using Bently Nevada systems (using non-contact proximity probes). In order to read the vibration accurately, there should be no mechanical runout (less than 0.0002") and negligible electric runout.

Our current practice is to machine the probe track area in case there exists mechanical runout, and then grind or burnish the track area on a lathe machine to minimize electric runout.

Do you recommend to use buffing/polishing (using buffing wheels and polishing compound/rouge) as an alternative to burnishing or grinding. Also, does buffing/polishing provide similar surface properties to grinding and burnishing in terms of roughness, corrosion resistance and durability.

Your assistance is much appreciated.

Regards,

Albara A
Maintenance Engineer - Saudi Arabia
March 15, 2009

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This may not answer the first part of your question but indirectly answers your question about surface finishes in general. Normally the longer you work a part in a secondary operation, the smoother the part and harder the material becomes. This will also improve the corrosion resistance to some minor extent.

AF Kenton
retired business owner - Hatboro, Pennsylvania
March 26, 2009

API Standards outline that surface finish on probe areas shall be achieved "preferably" by burnishing. To me, this means that you can also do it as you propose as long as all other conditions are met.

Guillermo Marrufo
Monterrey, NL, Mexico
March 29, 2009