基于飞机制动缸渗漏问题的研究

通过了解使用情况、复查设计制造过程、断口金相分析技术、对比试验对飞机制动缸渗漏问题研究。结果表明,渗漏是由于制动缸活塞孔底破裂,刹车时液压油被挤出附着在制动缸表面。断口提示裂纹为多源疲劳断裂,疲劳源为内壁R2转角表面铬酸阳极化孔洞聚集处。制动缸端面内圆处承受较大弯矩是制动缸疲劳开裂的促成因素。采取改进机加和表面处理工艺,调整刹车系统上电自检压力等措施解决了问题。

Based on Aircraft Brake Cylinder leakage Research

The brake cylinder leakage of aircraft was researched by investigating the usage, reviewing the design and making process, fracture metallography analysis and comparative test. The results show that the leakage resulted from the brake cylinder cracking at the piston cavity bottom, as so the hydraulic oil squeezed out and attached to the surface of the brake cylinder during braking. The fracture suggests multi-source fatigue cracking originated in accumulation pits of surface chromic acid anodizing at R2 zone. The larger bending moment on the inner circle of the end face of the brake cylinder was the contributing factor to the fatigue cracking of the brake cylinder. The improving machining and surface treatment process were taken and the power-on self-test pressure of brake system was adjusted to solve the leakage problem.