Abstract
Keywords:
High pressure power steering, Stress Relaxation, Finite element analysis, Swaging process
Abstract
Finite element analysis is conducted to improve the sealing performance of High Pressure Power Steering (HPPS) hose which is composed of metal fitting and multiple rubber layers. Since the hose sealing performance to avoid leak is strongly related to distributed contact pressure between metal fitting and swaged hose, the swaging process and hose expansion with internal fluid pressure is continuously simulated by MSC.Marc. Rebar element technique is used to describe the braided fabric reinforcement layer which increases the stiffness of hose, and the developed analysis model is shown a good agreement with the internal pressure expansion experimental result. In order to get the hyper-elastic material characteristic of rubber layers, uni-axial tension, planar shear, and equi-biaxial tests are conducted at room and high temperature, and the Ogden coefficients are fitted with material test data. To describe the visco-elastic characteristic of rubber layer, stress relaxation material test is also performed. The shape of real swaged part and analysis result are compared and correlated to prove the reliability of developed analysis technique. Through the cyclic internal pressure leak test, it is concluded that the new design optimized by FE analysis is improved on the anti-leak performance.