Effect of Worn Components on Brake Forces in a Freight Car Rigging

摘要

A braking test program was conducted to investigate the extent of and causes forsignificant variations in braking thermal input to railcar wheels. The program consisted of the following tasks: Brake force data was reviewed from previous test programs and computer simulations of brake forces in several types of conventional brake rigging were performed. Analytical and experimental investigations were conducted to evaluate the effect of worn components on the distribution of brake forces for a conventional brake rigging containing bent, unequal length levers. Tests were performed to determine: (1) the effect of extreme shoe placement on wheel temperatures developed during drag braking conditions, (2) friction characteristics of three brands of brakeshoes during extended drag braking, and (3) the friction characteristics of brakeshoes with simulated metal pickup.