对断裂油管短节和新油管短节材质进行了对比试验,并对所用吊卡和油管接箍主要配合尺寸进行了测量和分析,发现吊卡磨损之后承载面孔径变大,油管接箍承载面本身偏小。根据尺寸测量结果,推断出了油管断裂时与吊卡的非正常配合状态。对油管断裂时的受力状态分析结果认为油管短节失效过程为：接箍一侧承载面滑入磨损的吊卡承载面内孔里边,管体倾斜与吊卡上活门体下端面内圆弧棱相撞产生裂纹和变形,最后在偏斜拉伸和冲击载荷共同作用下断裂。

The macro-fracture and micro-fracture of broken tubing joint were analyzed,the material properties of fracture tubing joint and the new tubing joint were compared by testing. It was found that tubing elevator face borne was worn severely,and its bore diameter was larger than that specified in standard,and the shoulder dimension of tubing joint coupling that bears the weight of the tubing string was smaller than that specified in standard by measuring dimension of broken tubing joint and the tubing elevator. The load borne on tubing joint was discussed based on the test result of fracture morphology analysis,material property and dimension measurement. According to test and analysis result,it is concluded that the tubing joint broke process as the follows: one side of the coupling face borne load slipped into the bore of the elevator,then cracked and deformed because tubing joint is inclined and stroke with down circularity arc edge of the elevator bore,and finally broke due to impact load and deflexion tension load.