Load spectrum determination of tubing inwall proves the tubing is acted by the axial alternating load in a rod pumped well, and all the fractures are located at the root of the tooth.

• 油管内壁载荷谱测定进一步明确了油管在工作状态下承受轴向拉-拉交变载荷,其断裂部位全部在应力集中的齿根处。对油管断口进行了宏现和微观形貌分析。