伸缩油缸通油管总成断裂失效分析  

Fracture failure analysis of telescopic cylinder oil pipe assembly

作　　者：王温银[1] 赵舒涛[1] 刘启文 

机构地区：[1]中国矿业大学材料科学与工程学院,江苏徐州221116 [2]沧州中星穿越钻具有限公司,河北沧州062650

出　　处：《金属热处理》2016年第5期191-194,共4页Heat Treatment of Metals

摘　　要：采用宏观形貌分析、断口形貌分析、显微组织观察、硬度测试等手段,对伸缩油缸通油管总成的断裂原因进行分析。结果表明,通油管总成的断裂类型为宏观脆性断裂,裂纹源位于活油管焊趾处的熔合线上,管壁一周焊趾处都产生了裂纹并向内壁扩展形成断口的放射区,最后断裂区在内壁形成剪切唇。引起断裂的主要原因是活油管表面的镀铬层残留在熔合线上,裂纹源从镀铬层界面起裂,最后导致活油管在焊接处断裂。The fracture causes of the telescopic cylinder oil pipe assembly were investigated by macro-morphology analysis, fracture morphology, microstructure observation and hardness test. The results show that the fracture type of the oil pipe assembly is macroscopic brittle fracture, and the crack source is located at the fusion line of the oil pipe weld toe. Moreover, the cracks originate at the weld toe along the circumference of the pipe and expand towards the inner wall to form the radiation region of the fracture. And finally, the fracture zone forms at shear lip area in the inner wall. The main cause of the fracture is that the residual chrome plating in the surface of the movable oil tubing remained on the fusion line, and the source of crack occurs in the interface of the chromium plating, which finally results in the fracture of movable tubing in welding areas.

关 键 词：脆性断裂 镀铬层 焊接 熔合线 

分 类 号：TH137.51[机械工程—机械制造及自动化]