发动机油尺透明板裂纹原因分析

多次发现航空发动机滑油箱油尺透明板出现裂纹。为查明油尺故障原因,对故障件的外观、断口、尺寸、材质和力学性能等进行了综合分析。结果表明:油尺尺寸超差和平面度过大,导致故障件装配应力和整机应力偏大,直接造成透明板发生脆性断裂。在上述分析的基础上,采取改变设计尺寸、盖板材料、加强外观质量控制等措施,使透明板的装配应力和整机应力显著下降,有效预防了滑油箱油尺透明板裂纹故障。

Failure Analysis of Liquidometer in Aeroengine

Cracks have been found on transparent-plate which on the ]iquidometer of an aeroengine repeatedly. The appearances, fracture surfaces, material, size, mechanical property of the malfunction liquidometer were analyzed. Results show that the size of the liquidometer over tolerance and the depth of parallelism is excessive, that caused the increasing of the assembly stress and the stress of the overall engine led to this fracture malfunction. Some improvements were taken, changing the size of liquidometer and the material of the covers, enhancing the appearance quality, lowered the assemb]y stress and unitary stress significantly. These measures worked and the malfunctions of the transparent-plate were prevented effectively.