Abstract:The sealing performance of rubber O-ring used for high temperature thermal mining tool was studied at high temperature and high pressure.With the help of large scare finite element analysis software ANSYS,the two-dimensional axisymmetric finite element models of rubber O-ring and its boundary were built.Some factors influencing maximal contact stress,shear stress and Von Mises stress of sealing face were analyzed,such as oil pressure,assembly gap and friction coefficient.The influence of temperature on the stress of O-ring was investigated by using thermal stress coupling analysis method.Results show that oil pressure and assembly gap have great effect on the stresses,however,friction coefficient has little effect on the stresses.With the increasing of temperature,the maximum shear stress and contact stress are decreased,and maximum Von Mises stress is decreased obviously.The appropriate working temperature should be guaranteed to promote the sealing reliability of high-temperature thermal mining tool.