ASSESSMENT OF RESIDUAL RESOURCE OF CAST PARTS FREIGHT CAR TRUCKS ON THE RESULTS OF TESTS OF SAMPLES OF ENDURANCE

Resumen

The article desribes the existing and new methods of assessing residual resource of cast parts of the freight car bogies. The existing method is based on obtaining fatigue characteristics of the parts by way of performing field tests for endurance. It has been shown that these tests are extremely labor-consuming, require considerable costs and special equipment. The new method of assessing residual resource of cast details is based not on the fatigue test performed on the actually operated parts, but on testing of the samples, which are made of the parts that have already exceeded their service term (30 years). The testing of the samples is performed under symmetrical cycle of loading, under the cantilevered bend with rotation. The fatigue characteristics of material of the parts, after they have passed their service term, and the range of operational dynamic loadings in the part are the basis for their residual resource assessment. The experiment has shown that expenses for fatigue test of the parts are 5 times less than those for the parts testing on location. The method, derived from the results of samples testing, has passed all-round approbation. The difference in results of the residual resource assessment of bogie sideframes and bolsters of the freight cars in the parts testing on location and the samples testing does not exceed 6%.