Investigation of local hot spots in sealing rings with different sealing materials

The local high temperature in the sealing pair is prone to cause local wear, which easily leads to seal failure. In this paper, a numerical method based on the finite element method is proposed to investigate the local high-temperature hot spot in a sealing ring with different sealing materials. The distribution of hot spots on the sealing surface is visualized by numerical computations. The critical speeds of the hot spot for the metal, composite, and powder metallurgical sealing materials are obtained under different friction coefficients. Based on the obtained results, the quantitative correlation between the critical speed of the hot spot and elastic modulus, thermal conductivity, specific heat capacity, thermal expansion coefficient, and seal sizes is determined. Then, a test method is designed to evaluate the thermal instability of the sealing ring. Scanning electron microscopy is utilized to examine the surface morphology of the sealing rings after the hot spots appear. The results of the present study demonstrate that the proposed method is consistent with the experiment. It indicates the effectiveness of the simulation method for investigating local hot spots in the sealing ring.