Research of Mechanical Load and Wear of Valve Seat 2013-01-2652

In order to analyze the fatigue life and wear loss of valve seat, a simplified approach was developed to predict fatigue life and wear loss, and a test was conducted to testify the prediction in this paper. Aimed at revealing the effect of mechanical load and thermal load on the fatigue life and wear loss of the valve seat at different camshaft speeds, the ABAQUS software and the experimental data obtained from the valve train test bed were used to predict the fatigue life, which was based on the energy method. The mechanical stress, thermal stress, temperature distribution depending on material properties, and thermal-mechanical coupling stress at different camshaft speeds have been considered in the finite element method simulation. Through analyzing finite element analysis model of valve seat and S-N curve, the fatigue life and wear loss could be both obtained.

It can be seen from the analysis that the mechanical load and thermal load influenced the fatigue life and wear loss of the valve seat collectively. Besides, the mechanical load was the dominant influence factor under high speed conditions, while the thermal load's effect is relatively small. Particularly, the wear loss has no relationship with contact surface area, but it is related to the pressure. Based on the calculation results of fatigue life and wear loss, it can be concluded that the contact surface between valve and valve seat is the weakest area, and the fatigue life and wear loss can match with the theoretical prediction perfectly.