Study, analysis and design of bolster spring used in ICF railway coaches

Abstract

The springs used in the bogie suspension of railway coaches are compression springs. They are made of an elastic wire material formed into the shape of a helix. They are commonly referred to as a coil spring or a helical spring. They are used to store energy and subsequently release it to absorb shock or to maintain a force between contact surfaces. The spring returns to its natural length or position when unloaded. Spring (BOLSTER) used in railway coaches have been failing prematurely much before their intended service life. The springs are made with quality materials. Visual examination shows that failure is common between first to third coils. The exact time of failure cannot be determined as the coaches come for POH after 18 months. Some cracks also negotiate during load testing. Pattern of cracks showing it may subject to transverse forces. The cracks are detected in Magna-flux testing. The present works attempt to analyze design of secondary suspension springs used in Railway coaches under transverse loading by using ANSYS 19.1 software. Stresses induced are compared with allowable stresses. Typical 13T NON-A/C coaches have been considered for the failure analysis. Keywords: Bolster spring, Magna-flux testing, Ansys 19.1