Abstract: As the number of high-temperature，high-pressure and ultra-deep oil and gas wells continues to increase，conventional G105 and S135 drill pipes can no longer meet the job needs of trouble wells. As a new type of high-strength drill pipe，V150 drill pipe has a performance superior to traditional steel drill pipe. To study the applicability of V150 drill pipe in the workover jobs of ultra-deep wells，basic performance parameters such as chemical composition，hardness and impact energy of V150 drill pipe samples were tested first. The test results show that all indicators of V150 meet industrial requirements. And then，the rotating bending fatigue test of V150 drill pipe in air and mud was carried out，and its S-N curve was obtained. The fatigue test results show that V150 drill pipe is highly sensitive to mud. The fracture analysis shows that the fracture of the V150 drill pipe sample is resulted from the combined action of oxygen corrosion and stress，as well as the accelerated corrosion rate due to the existence of Cl^- in mud. Finally，the actual use of V150 drill pipe was discussed in combination with the testing results. The results show that the maximum hook load to release stuck drill pipe has been reduced from 1 784 kN to 1 717 kN after the V150 drill pipe assembly was used，and the job safety factor has been increased from 1.16 to 1.41. The study in this paper can provide theoretical basis and guide for the safe use of V150 drill pipe in the workover jobs of ultra-deep wells. 

Key words: V150 drill pipe, mechanical performance tes, fatigue performance, ultra-deep well, safety factor

摘要： 随着高温高压超深油气井的开采数量持续增加，常规的G105和S135钻杆已经无法满足复杂井的作业需求。V150钻杆作为一种新型高强度钻杆，相比于传统钢钻杆有着更好的性能表现。为了研究V150钻杆在超深井修井作业中的适用性，首先进行了V150钻杆试样的化学成分、硬度以及冲击等基本性能参数测试。测试结果表明V150钻杆各个指标均满足行业要求。其次进行了V150钻杆在空气及钻井液中的旋转弯曲疲劳试验，得到了V150钻杆在空气和钻井液中的S-N曲线。疲劳试验结果表明V150钻杆对钻井液有着极高的敏感性；断口分析表明V150钻杆试样的断裂是氧腐蚀和应力共同作用的结果，在腐蚀过程中钻井液中的Cl^-进一步加快腐蚀速率。最后，结合试验结果对V150钻杆的实际使用情况进行了讨论。采用V150钻杆组合后解卡作业最大钩载由1 784 kN降为1 717 kN，作业安全系数由1.16提升到1.41。该研究内容可为V150钻杆在超深井修井中的安全使用提供理论依据及指导。

关键词: V150钻杆, 力学性能测试, 疲劳性能, 超深井, 安全系数