宽温度域工况下汽车水泵O形密封圈的密封性研究

Study on Sealing Property of O-ring Seal of Automobile Water Pump under Broad Temperature Region

针对汽车发动机水泵 O 形橡胶密封圈宽温度域的工况特点，构建其与温度相关的 Mooney飊Rivlin材料模型，探讨冷却液温度、压力、摩擦因数等对 O 形密封圈接触压力、等效应力以及密封性的影响。研究表明：温度的升高将引起接触压力及等效应力的峰值呈幂指数减小，导致密封可靠性降低，但在宽温度域（-40-130℃）工况下，接触压力的峰值始终远大于液体压力，因此该密封圈具有可靠的密封性；液体压力的增大虽然会引起接触压力峰值增大，但其增大的速度比液体压力增大的速度小，因此将引起密封可靠性下降；摩擦因数对密封可靠性的影响不大。

Based on the characteristics of rubber O-ring of an automobile engine water pump working in wide temperature domain,a Mooney-Rivlin material model which was relevant to tempera-ture was established to reveal the influences of temperature,fluid pressure and friction coefficient on the contact pressure,equivalent stress and sealing property.The results show that the increase of temperature causes the peak of contact pressure and equivalent stress to decrease exponentially,indu-cing the sealing reliability reduces.However,the peak of contact pressure of O-ring working in -40~130℃ is considerably larger than that of the fluid pressure,so the O-ring has reliable sealing prop-erty.Furthermore,although the increase of fluid pressure induces the increase of the peak of contact pressure,the reliability of sealing will decline for that the increasing speed of contact pressure is lower than that of fluid pressure.Additionally,the friction coefficient has little influence on the reliability of sealing.