螺旋槽机械密封性能影响因素的解析法分析

端面开有螺旋槽的机械密封能有效地解决普通接触式机械密封端面摩擦和磨损严重等问题 ,研究影响螺旋槽机械密封性能的结构因素和操作因素对设计和应用该类密封具有重要意义。鉴于此 ,运用解析方法分析了影响端面外侧开有螺旋槽的泵入式机械密封性能的操作因素和结构因素 ,并与相应的内侧开槽泵出式密封环进行比较。结果发现 ,边界压力、介质粘度、轴转速、非槽区液膜厚度等操作参数对密封性能有重要影响 ;开槽深度和螺旋角等结构参数对密封性能也有重要影响。在同样条件下 ,外开槽泵入式密封环的开启力和液膜刚度大于内开槽泵出式密封环的开启力和液膜刚度。

A theoretical analysis offactors affecting the seal performance of spiral groove mechanical seals.

The mechanical seal with one end face spirally grooved has betterperformance compared with the conventional contacting mechanical seal, which often meets with the problems of friction and heavy wear. It is of great importance to investigate the structural parameters and the operating parameters that affect the spiral mechanical seal performance. A theoretical analysis is conducted to the operating parameters and the structural parameters affecting the sealing properties of a “pumping in” spiral groove mechanical seal with grooves in the outer part of the seal ring, and a comparison is made between the “pumping in” and relevant “pumping out” seal rings. The result of the analysis shows that, the operating parameters, such as the medium pressure and viscosity, the shaft speed and the thickness of the liquid in the non-grooved area, have great influence on the sealing performance. And the influences of such structural parameters as the groove depth and the angle of the spiral line are also notable. The opening force and film stiffness of the “pumping in” mechanical seal are greater than those of the “pumping out” mechanical seal under the same conditions.