弹簧比压对平衡型机械密封基本性能的影响

弹簧比压是形成机械密封端面密封比压的重要组成部分。分析了弹簧比压对平衡型机械密封摩擦特性和密封性能的影响,利用自行研制的动态下弹簧比压可控机械密封试验装置对平衡型机械密封进行了试验。研究表明,弹簧比压不仅使机械密封端面贴合,而且会使得粗糙端面的接触点产生变形,形成较小的密封间隙。对于平衡系数与膜压系数相近的机械密封,弹簧比压对泄漏量的影响明显增大。尽管弹簧比压的变化有时不足以改变机械密封的端面摩擦状态,但随着弹簧比压的增大,摩擦副之间的润滑介质相对减少。兼顾摩擦特性和密封性能两方面的要求并正确选择弹簧比压,是使机械密封处于最佳工作状态的要点。

Influence of spring pressure on basic performance of balanced mechanical seals

Spring pressure is an important portion of the mechanical seal face mean contact pressure.The effect of spring pressure on friction characteristic and seal capability of the balanced mechanical seal is analyzed,and the balanced mechanical seal is tested in the test device which spring pressure of mechanical seal can be adjusted during its operation.The research results show that spring pressure not only make two faces of mechanical seal contact each other,but also results in the deformation of contact points of roughness faces and forms a small gap.When the balance factor is near to the film pressure factor,spring pressure will apparently influence the leakage rate of mechanical seals.Though the fraction condition of seal faces is not varied with the change of spring pressure at times,lubricant medium between two seal faces will be decreased with spring pressure increasing.Considering friction characteristic and seal capability synthetically,it is pointed that appropriate selection of spring pressure is key to the mechanical seal operation under the best condition.