February 1, 2022
Taking Care of your Spares
By Stan Riddle
Rotating equipment, either in storage, or down for long periods of time, should be rotated on a regular basis.
This prevents two things:
- rust forming in the bearings, gears, etc., due to lubricant settling into the reservoir.
- false brinelling, which is micro-spalling of the bearing raceways due to impacting. This occurs when vibration is present from nearby machines, forklift traffic, check valves slamming, or anything else that might cause vibration on a non-running machine. This vibration can damage even new bearings and seals.
Machinery operating on a common platform or header should be rotated on a weekly or monthly basis. If this cannot be done, pumps should be rotated by hand, a few revolutions.
Spares stored either in a equipment room, or in a supply room should be:
- Properly lubricated for storage
- Rotated by hand, a few revolutions, on a weekly or monthly basis
- Equipment should be stored on racks or a wooden pallet (or even better, on neoprene isolator pads ) to minimize the effects of vibration from nearby operating equipment), and not on a concrete floor.
Machinery in long term storage outside should be covered overhead. But NOT wrapped in a tarp or shrink-wrap, due to condensation. In addition, the oil in these machines should be sampled annually, to make sure you don’t have water in bearings and gearboxes.
Back when I was collecting vibration data, I would just go around in pump rooms, and rotate the spares by hand while I was there. In some buildings we had a quarterly PM to go to our supply rooms, and rotate equipment.
Is it a little more trouble? Yes. But not as much as having a back-up pump that can’t run!