机械密封的失效模式与临界平衡比的计算

介绍了与机械密封面积比（平衡比）有关的几种主要失效模式，如密封面开启失效、早期磨损、干运转、热裂、疱疤、相态失稳、倾斜失稳、液膜失稳、液膜破裂、汽化和丧失密封性等，并提出了考虑主要失效现象的临界平衡比公式。根据临界面积比的大小，可以判断所选用的机械密封平衡比是否合理；并进一步来确定该机械密封的合适面积比，给出了计算实例，计算结果可供机械密封设计时选用。

SEALING FAILURE MODES AND CRITICAL BALANCE RATIO FOR MECHANICAL FACE SEALS

Several failures modes related to the area ratio (balance ratio) of mechanical face seals are introduced. They are seal face opening, premature wear, dry running, heat checking, blistering,phase state instability, fluid film instability, inhibition of fluid film formation, fluid film rupture, vaporization and excessive liquid leakage. Formulae of critical area ratio for these failure modes are presented. Suitable area ratios can be selected by considering these critical area ratios. Several calculation examples are given. The results are available for mechanical seal design and application.