渣浆泵双端面机械密封密封环热力耦合分析

Thermal-Stress Coupling Analysis on Sealing Ring for Double Mechanical Seal of Slurry Pump

针对磷酸厂渣浆泵机械密封因端面变形而导致的使用寿命缩短问题,以渣浆泵背对背型双端面机械密封密封环为研究对象,采用整体法,根据实际工况建立密封环热力耦合三维计算模型,研究密封环温度场分布及端面变形情况,分析不同工况下密封环热力变形对机械密封正常工作的影响。结果表明:密封环最高温度出现在静环内侧,且温度沿径向朝静环外侧逐渐降低;环境温度对密封环热力变形有显著影响,高温环境下机械密封更容易失效;密封端面受到热力耦合的影响,从平行面变为收敛面,造成密封面迅速磨损,泄漏量增大;根据端面变形形状,可考虑将该机械密封改造为非接触式机械密封,从而提高使用寿命。

Aimed at the problem of service life shortening of mechanical seal of slurry pump in phosphoric acid plant due to end face deformation,taking the seal ring of back-to-back double mechanical seal of slurry pump as the research object,a three-dimensional thermal-stress coupling calculation model of the seal ring was established by using the integral method according to the actual working conditions.The temperature field distribution and end face deformation of seal ring was studied,and the effect of thermal-stress deformation of seal ring on the normal operation of mechanical seal under different working conditions was analyzed.The results show that the highest temperature of the seal ring occurs at the inner side of the static ring,and the temperature gradually decreases along the radial direction toward the outer side of the static ring.The environmental temperature has a significant impact on the thermal-stress deformation of the seal ring,and the mechanical seal is more prone to failure at high temperature environment.Under the influence of thermal-stress coupling,the sealing face changes from parallel surface to convergence surface,resulting in rapid wear of the sealing surface and the increase of leakage.According to the deformation shape of the end face,the mechanical seal can be considered to be transformed into a non-contact mechanical seal,so as to improve its service life.