Contact analysis of Type17 coupler based on finite element method

Fatigue cracks of the hook tongue components in Type17 coupler usually occur on its S-surface under improper working conditions. Stress of S-surface mainly consists of tensile stress, bending stress and contact mechanics on the contact surface in stretch conditions. Finite element method with pure penalty algorithm, which discovers the details of stress distribution on S-surface contact regions in contact analysis, is proposed. Stress interpolation curves illustrated the effect of contact to stress concentration on S-surface by extracting the surface stress data. Several peaks value of stress caused by surface contact in contact areas coincide with Hertz stress. According to the comparative analysis, an improved design, which avoids line contact under stress condition, made the four main peak value of stress in the original design decreased by 18.1%, 18.2%, 10.0% and 14.0% respectively. The results conduct that the proposed approach is feasible and the improved design is one way for improving stress condition of hook tongue components.