喷丸强化技术在某型作动筒延寿修理中的应用

目的将某型作动筒的寿命由6000±150起落延长至12 000±150起落。方法采用喷丸强化技术对作动筒的主要承力零件进行喷丸强化处理,提高零件的抗疲劳和抗应力腐蚀性能。通过疲劳寿命试验验证对比喷丸强化处理前后典型零件和作动筒的寿命指标是否达到了预期目标。结果喷丸强化处理前的3件前耳环螺栓试验循环次数均未超过1.8×10~6即断裂,喷丸强化后达到3.6×10~6时仍未断裂。喷丸强化处理后的4件主耳环螺栓与喷丸强化处理前对比,断裂时的试验循环次数均有不同程度的提高,均值寿命比值大于2.36。喷丸强化处理前后的主前作动筒疲劳寿命试验达到预期的循环次数时,均没有出现断裂或者损坏。结论喷丸强化处理能有明显提高作动筒的抗疲劳和抗应力腐蚀性,强化处理后的零件疲劳寿命能够超过处理前的2倍,可以采用喷丸强化技术延长作动筒的使用寿命。

Application of Shot Peening Technology on Lifetime Extension Repair of an Actuator Cylinder

Objective To extend the lifespan of an actuator cylinder of an aircraft landing gear from 6000±150 times to 12000 + 150 times. Methods Shot peening technology was adopted to improve the fatigue resistance and stress corrosion resistance of the main bearing parts of the actuator barrel. The life expectancy of typical parts and actuators before and after shot peening treatment was verified through fatigue life test. Results Through the fatigue life test, it was proved that the test cycle times of 3 front earring bolts were not more than 1.8 ?106 before breaking. While there was no breaking when the test cycle times of 3 front ring bolts after shot peening reached 3.6 ? 106. Compared with the fatigue life test results of 4 main earring bolts and 4 main earring bolts before shot peening, the test cycle times of the fracture were improved in varying degrees; the mean life ratio was greater than 2.36. There was no crack or damage when the fatigue life test of the main front actuating cylinder before and after the shot peening treatment reached the expected cycle times. Conclusion Shot peening treatment can obviously improve the fatigue resistance and stress corrosion resistance of the actuator. The fatigue life of the parts after strengthening can exceed 2 times the fatigue life of the parts before the reinforcement treatment. The shot peening technology can be used to prolong the service life of the working cylinder.