封严环配合止口等离子喷涂再制造工艺

Remanufacturing Process of Sealing Ring Rabbet by Plasma Spraying

针对航空发动机大修过程中发现的封严环与低压涡轮第1级盘配合止口严重磨损问题,对封严环基体GH38合金等离子喷涂镍铬铁钼涂层后进行外观检查,开展弯曲性能检查、金相组织检查和拉伸结合强度检查试验,并对封严环基体最大去除量进行强度分析、封严环再制造工艺方法分析和封严环再制造零件几何参数对比分析,对修复合格的封严环进行长试试车考核验证。结果表明:修复后的封严环配合止口直径、跳动、粗糙度、同心度符合设计要求,不平衡量符合设计要求,试车后在封严环配合止口处镍铬铁钼涂层无脱落、无掉块,涂层状态及检查结果均完好;封严环采用等离子喷涂镍铬铁钼涂层修复配合止口喷涂工艺稳定;封严环配合止口车削加工参数选择正确;加工工艺方法稳定。

To solve the problem of serious wear of the mating surface between the sealing ring rabbet and the first-stage disk of the low-pressure turbine found during the overhaul of the aeroengine,visual inspection was conducted after applying plasma spraying Ni-Cr-Fe-Mo coating on the sealing ring base made of GH38 alloy.Bending performance inspection test,metallographic structure inspection and bonding strength tensile test were carried out,and strength analysis for the maximum removal amount of sealing ring,sealing ring remanufacturing process analysis and geometric parameter comparison analysis of sealing ring remanufacturing parts were conducted.A endurance test was carried out to verify the repaired sealing ring.The results show that the diameter,runout,roughness and concentricity of the repaired sealing ring rabbet satisfy the design requirements,and the unbalance meets the design requirements.After the test,the Ni-Cr-Fe-Mo coating of the sealing ring rabbet was in good condition,exhibited no spalling and falling off,and all inspection results passed.The repairing process of plasma spraying Ni-Cr-Fe-Mo coating is stable,the turning process parameters of sealing ring mating rabbet are correctly selected,and the process method is stable.