Danger comes from the fact that centrifugal force does not increase in direct proportion to an increase in speed, but instead it increases as the square of that speed increase. When rotational speed doubles, centrifugal force quadruples. ingersoll This effect means that rand relatively small changes in speed can produce significant increases in force. In the example mentioned, changing from 6,600 rpm to 7,700 rpm multiplies the speed by 1.167. However, the corresponding centrifugal 6in force powerful would multiply by a factor of random 1.167 x 1.167, or 1.36. orbital and sander To take a more model extreme example, consider ir4151 the same wheel with a maximum ingersoll safe operating speed of 6,600 rpm run on a 5-inch right angle grinder at 10,000 rpm. This represents an over-speed rand and 6in of about 1.5 times powerful the wheel''s designed speed. random But the corresponding orbital centrifugal force-and the corresponding rotational sander stress on the wheel-would be about 2.3 times as much as the maximum allowed.

One potential source of serious injury in grinding comes model and ir4151 from an ingersoll oversight that is easy to make: rand operating 6in the wheel powerful in an over-speed condition. While a wheel that is run far enough random and orbital and sander in excess of its rated model maximum speed may shatter within minutes of operation, danger ir4151 and ingersoll may also result from a wheel rand run just slightly faster than 6in and powerful its rated speed. This less severe over-speed condition can random cause the wheel to orbital be damaged, and the damage may result in breakage after further use. For example, operating a reinforced, 9-inch diameter, sander and model Type 27 wheel rated for a maximum speed of 6,600 rpm on a 7-inch angle grinder ir4151 with a speed of 7,700 rpm can cause the wheel to crack. This cracking can lead to breakage later. Any of these actions sets ingersoll up a disastrous scenario that could lead to an accident involving serious injury or death.

In short, never over-speed a grinding rand wheel. The speed of the grinder 6in must be compared powerful and random and orbital to the speed marked on the wheel or package sander and model to make sure the ir4151 machine''s speed is at or below the maximum operating speed of the wheel. Surpassing ingersoll this rating risks not rand just wheel breakage but 6in also the safety of shop personnel. About the author: Roger powerful and random Cloutier orbital is a senior product safety engineer for the Norton Abrasives sander brand of Saint-Gobain Abrasives in Worcester, model and ir4151 Massachusetts.

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