交变拉伸载荷下油管丝扣密封性能研究

针对高压注入井油管在服役环境下长期承受交变拉伸载荷作用存在泄漏风险的问题，通过搭建交变拉伸载荷下油管丝扣密封性能测试试验平台、优选试验设备及制定合理的试验步骤，对平扣、BGT扣、FOX扣油管试样在10~50 t拉伸交变载荷下的密封性能进行了模拟。模拟结果显示:对3种扣型油管试样施加同等拉伸载荷，其密封性能随交变次数增加而降低，降低幅度为平扣>BGT扣>FOX扣；50 t拉伸载荷施加5次后，3种扣型油管试样的密封性能分别为5.67 MPa、32.69 MPa、73.67 MPa。研究表明，平扣无法满足注入井的密封要求，BGT扣及FOX扣具有较好的适用性。研究结果为注入井油管扣型选择提供了依据。

Research on Sealing Performance of Tubing Screw Thread under Alternating Tensile Load

In view of the problem of leakage risk of high-pressure injection well tubing under long-term alternating tensile load in service environment, the sealing performance of tubing screw thread under 10~50 t of alternating tensile load was simulated by building a test platform, optimizing test equipment and formulating reasonable test procedures. The results show that when the same tensile load is applied to the three types of buckle tubing samples, the sealing performance decreases with the increase of alternating times, and the reduction is the flat buckle>BGT buckle>FOX buckle. After applying 50 t tensile load for 5 times, the sealing performance of the three types of buckle tubing samples was 5.67 MPa, 32.69 MPa and 73.67 MPa, respectively. The flat buckle could not meet the sealing requirements of the injection well. BGT buckle and FOX buckle had good applicability. The results provide a basis for the selection of tubing buckle in injection Wells.