某型直升机尾减速器从动机匣腐蚀故障分析及预防对策研究

目的分析某型直升机尾减速器从动机匣腐蚀故障原因,建立预防该类腐蚀故障问题的处理方法。方法通过腐蚀故障机基本信息分析,腐蚀故障部位结构、材料和腐蚀形貌分析,得出腐蚀故障原因,采取"原位"处理方式建立该类腐蚀故障处理方法。结果某型直升机尾减速器从动机匣安装面有异种金属接触和凹陷型结构,并承受交变载荷,易发生腐蚀故障,部队外场维护只能通过检查和监控延缓腐蚀进程,解决该问题需通过"湿装配"的密封剂处理技术和螺栓表面防护加强方法。结论采取机上原位进行尾减速器从动机匣螺栓固定端面"湿装配"密封处理和螺栓外表面防护涂层加强处理,能够防止电解液进入螺栓固定端面和螺栓孔内部,达到腐蚀预防的目的。

Corrosion Failure Analysis and Preventive Measure of a Type of Helicopter Tail Gearbox Casing Assembly

Objective To analyze the cause for a type of helicopter tail gearbox casing assembly corrosion and to establish a preventive measure. Methods Through the analysis of basic information on corrosion failure, corrosion location structure, material and appearance, we concluded the cause for the corrosion and established the preventive measure with an insitu treatment. Results There were dissimilar metal contact and concave structure on the fitting surface of the type of tail gearbox, and corrosion occurred easily under cyclic loading. The army field maintenance could only delay the corrosion process through inspection and monitoring. To solve the problem, wet assembly of sealant processing techniques and blot surface preventive strengthening were required. Conclusion With in-situ tail gearbox casing assembly fitting surface wet assembly and blot surface preventive strengthening, it was able to prevent electrolyte from infiltrating the fitting hole, and to achieve the purpose of corrosion prevention.