Wheel thermal damage limits

A series of dynamometer tests were conducted to determine the limiting power required to produce wheel thermal damage, or the neutralization of the as-manufactured rim circumferential residual compressive stresses. Dynomometer and saw-cut tests were conducted on low-stress heat-treated CE-28, CH-36 and CB-38 freight car wheels to determine the onset of damage. The effects of various combinations of time and brake shoe power inputs, as well as the effects of rim thickness and the presence of the rail wheel, on the resistance of wheels to thermal damage were investigated. The test results showed that the amount of brake shoe thermal input required to thermally damage heat-treated low-stress wheels is far in excess of that of normal brake application.<
>