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Machinery & Equipment MRO
April 2022
SAFETY AND BEARINGS
O
ver the years, there have been many situations in which there are safety concerns related to bearings, typically during installation and removal.
Mounting bearings safely
In the paper and mining industry, large diameter bearings are often used. The first step is to standing bearings on end as the wrapping is removed from them. This poses a risk of the bearing tipping, which can cause serious injury. The recommendation would be to ensure the bearing is slung, even if loosely, to an
overhead crane so that if the bearing tips, it is caught by the sling.
Pressing bearings onto shaft – do not hit bearing with hammer
Bearing steel is hardened and has some degree of brittleness. A hammer blow can cause a shard of steel to fracture and fly, and act like shrapnel. The shard can cut through the material of the millwrights clothing, penetrating the skin.
Mechanically driving bearings up a tapered sleeve
Tapered bore bearings are mounted by
driving the bearings up a tapered adapter sleeve. Force is required to drive the bearing up the sleeve. Often the nut is used to push the bearing up the sleeve. To do this, a spanner can be used. However, as the bearing size gets larger, the spanner needs to be impacted to turn the nut. This is done by either impacting a special wrench designed for impact or using a drift applied to the slots in the nut. What often happens is that one millwright holds the drift and the other hits the drift with a sledge hammer. One false blow in a cramped area can cause an injury to the holder of the drift.
Photo: © Alexey Rezvykh / Adobe Stock
BY DOUGLAS MARTIN
