航空发动机燃-滑油热交换器焊缝裂纹原因分析  

Analysis on Welding Cracks in Fuellubricating Oil Heat Exchanger of Aeroengine

作　　者：杨坤玉[1] 徐小军[2] 潘存云[2] 罗成[2] 

机构地区：[1]空军航空维修技术学院,长沙410124 [2]国防科技大学机电工程与自动化学院,长沙410073

出　　处：《失效分析与预防》2011年第4期242-248,共7页Failure Analysis and Prevention

基　　金：空军装备部维改项目资助(Z1003)

摘　　要：某型航空发动机燃-滑油热交换器出现焊缝裂纹,导致漏油事故,补焊后短时间内又出现裂纹,严重危及飞行安全。通过对燃-滑油热交换器动力学、材料、制造工艺、工况等方面进行深入分析,指出燃-滑油热交换器焊缝裂纹的产生,是采用"一定三活"的安装方式所形成的"潜在故障区"、发动机高速运转时产生的振动应力集中、油液流动和温度场变化产生的热应力、燃-滑油散热器在焊接制造过程中存在的工艺缺陷、外界的气温上升使燃-滑油热交换器的热应力作用加剧等5个方面综合作用的结果。该研究结论对裂纹故障的修复与预防有重要的指导意义。Welding cracks occurred to a fuel-lubricating oil heat exchanger of an aero-engine and resulted in oil leakage. And oil leakage occurred again shortly after repair welding.This kind of fault is very dangerous to flight.In order to find out the cause of the failure,dynamics,materials,manufacturing process and working condition were comprehensively analyzed.The results showed that the welding cracks formed due to the combined effects of the follow five aspects： ＇potential failure zone＇ due to the ＇one stationary and other three floating＇ installation method,stress concentration resulting from engine vibration,thermal stresses caused by oil flow and temperature field change,defects produced during the welding manufacturing process,and heat stresses increasing with the outside temperature rising.The study results are important for guiding the repair and prevention of cracking.

关 键 词：航空发动机 燃-滑油热交换器 焊缝裂纹 

分 类 号：TG142.33[一般工业技术—材料科学与工程]