Reliability analysis based on load spectrum: A structural improvement of Indian Railways three-piece freight bogie elastomeric pad

Abstract

Dynamic characteristics and reliability of elastomeric pads are dominant components in the design methodology to satisfy the performance parameters under dynamic operations. The fatigue life of rubber pads fitted with elastomeric pads mainly depends upon elastomers; natural rubber, chloroprene, nitrile butadiene, silicon compounds, etc., additives, accelerators, activators, fillers, anti-degradants, and manufacturing processes. The performance of the elastomeric pad is evaluated based on service operation, simulation, and laboratory testing. New and failed elastomeric (EM) pads have been examined in the Indian Rubber Manufacturer’s Research Association IRMRA laboratory for detailed failure analysis of existing EM pads. Further, chemical and physical properties are also evaluated in M&C (Metallurgical and Chemical) and Testing Directorate of Research Designs and Standards Organization (RDSO), labs respectively. The fatigue life of the EM pad is estimated based on the results extracted from the Finite Element (FE) analysis of the EM pad. An attempt is made to modify the design of the EM pad by considering the results of detailed field trials, lab testing, and FE analysis. The modified design satisfies the dynamic characteristic during FE (Structural and Thermal) analysis and lab testing.