过盈配合公差对镶嵌式机械密封性能的影响研究

The Influence of Interference Fit Tolerance on Mosaic Type Mechanical Seal Performance

采用有限差分和有限元相结合的方法,通过建立耦合模型,分析镶嵌式流体动压型机械密封的配合公差对密封性能的影响。通过计算表明,选定的四种配合公差对机械密封的密封性能影响较小;配合公差对密封性能的影响与镶嵌结构和材料有关。针对该次计算结果和日常使用所遇到问题,建议在满足安全裕量的情况下,宜选取低级别的配合公差,并确保用于过盈连接的金属与密封环材料具有相同或非常接近的膨胀系数;针对过盈配合连接件内部的残余应力问题,可先对组件进行热处理,经处理后再对密封端面进行研磨。在经过上述处理后,可大大降低镶嵌式机械密封由于过盈而导致的失效风险。

By combination of finite difference and element method,the mathematic model was developed.The effect of the interference fit on mechanical seal performance was analyzed.It is found that the performance has been less affected by the fit tolerance.And the performance was concerned with the structure of interference fit and the material of the mechanical ring.Based on the calculating data and problems in use of the mosaic hydrodynamic mechanical seal,it is suitable to select the low level coordination tolerance and it has adequate safety allowance.The material of the metal and seal ring should maintain the same or close coefficients of expansion.For the problem of the residual stresses of the mosaic structure,the mosaic mechanical seal should undergo heat treatment first.Lap the surface of the mechanical seal ring after heat treatment.By taking these effective measures,the risk of the sealing failure can be significantly reduced.