Abstract

Due to their special flexible structure, finger seals show good wear and leakage characteristics and has a great application prospects. Under the condition of high speed, the sealing and wear performance of finger seals is directly related to the characteristics of the friction pair between the finger foot and rotor. As a kind of high polymer material with a lower friction coefficient, polytetrafluoroethylene (PTFE) has potential application value in finger seals. Therefore, based on the previous theoretical analysis and optimization design, in this study pin-on-disc tests between the metals applied in finger seals and the PTFE coating and bench-scale performance tests of finger seals with the PTFE coating were carried out. The results show that for finger seals made of the cobalt-base alloy GH605, the friction coefficient of finger seals with PTFE coating is only 0.15, which is 50% lower than that without the PTFE coating; after a 50-h durability test, the leakage performance of finger seals with the PTFE coating was more stable, and its leakage rate and wear rate were reduced by 30 and 39%, respectively, compared to without the PTFE coating. The test results in this article indicate that the PTFE coating has excellent wear resistance characteristics and good application potential for finger seals, which provides valuable reference for the design of the friction pair of finger seals.

摘要

由于其特殊的柔性结构，指形密封件具有良好的耐磨和泄漏特性，具有很大的应用前景。在高速条件下，指形密封件的密封和耐磨性能直接关系到指形脚与转子间摩擦副的特性。聚四氟乙烯（PTFE）作为一种摩擦系数较低的高分子材料，在手指密封件中具有潜在的应用价值。因此，在前期理论分析和优化设计的基础上，本研究对手指密封件中应用的金属与 PTFE 涂层进行了针盘式试验，并进行了 PTFE 涂层手指密封件的台架性能测试。结果表明，对于由钴基合金 GH605 制成的手指密封件，涂有聚四氟乙烯的指形密封的摩擦系数仅为0.15，比不涂聚四氟乙烯的手指密封低50%；经过 50 小时的耐久性试验，涂有 PTFE 涂层的指形密封件的泄漏性能更加稳定，与没有涂 PTFE 涂层相比，其泄漏率和磨损率分别降低了 30% 和 39%。本文的试验结果表明，PTFE涂层具有优良的耐磨特性和良好的指形密封应用潜力，可为指形密封摩擦副的设计提供有价值的参考。分别与没有 PTFE 涂层的情况相比。本文的试验结果表明，PTFE涂层具有优良的耐磨特性和良好的指形密封应用潜力，可为指形密封摩擦副的设计提供有价值的参考。分别与没有 PTFE 涂层的情况相比。本文的试验结果表明，PTFE涂层具有优良的耐磨特性和良好的指形密封应用潜力，可为指形密封摩擦副的设计提供有价值的参考。