某机构油箱端盖爆裂分析与改进研究

BURST FAULT ANSLYSIS AND IMPROVEMENT OF A FUEL TANK COVER

针对油箱端盖爆裂故障,结合断口形貌、失效分析确定其故障模式为疲劳断裂。通过现场检查与排故、设计图纸对比、有限元分析等手段对故障机理进行定位,确定端盖断裂位置为应力最大位置,端盖厚度不够是造成端盖的抗疲劳性能降低的根本原因。参考设计图纸,在保证端盖总高度不变的情况下,将端盖厚度由图纸规定的3 mm加厚到4mm可满足使用要求。研究改进结果得到认可,改进措施满足了使用安全并提升后续修理产品的可靠性。

According to the burst fault of a fuel tank cover,the failure mode was determined to be fatigue fracture based on the fracture morphology and failure analysis.By contrasting the different of design drawing and using finite element analysis method,the fault mechanism was located through troubleshooting process.The fracture position of the cover was determined to be the maximum stress position.Insufficient thickness of the cover is the fundamental cause of the fatigue resistance.According to the design drawing,the thickness of the cover increased from 3 mm to 4 mm meet the use requirements under the condition that the total height of the cover remains unchanged.The results of the study were recognized by the customer and the improvement measures ensured the safety and reliability of the aircraft in service.