通过分析影响汽液两相机械密封稳定性的各种因素,讨论了汽液两相机械密封在工况变化时的端面比压的变化及影响因素,提出了汽液两相机械密封在变工况发生时的端面失效形式判据,利用实验室实验手段验证了汽液两相机械密封在工况变化时的开启失效与影响比压的各种因素变化特别是端面膜压的变化有必然的联系。 By analyzing various factors that affect the stability of vapor-liquid two-phase mechanical seal, the change of end-face specific pressure of vapor-liquid two-phase mechanical seal and its influencing factors are discussed. When the occurrence of the end surface failure criterion, the use of laboratory experiments proved that the vapor-liquid two-phase mechanical seal in the working condition changes when the opening failure and the impact of pressure than the changes in various factors, especially changes in end membrane pressure is inevitable contact.