钻杆接头螺纹粘扣原因分析

Cause analysis of drill pipe joint thread galling

余世杰 袁鹏斌 魏立明 刘贤文 高健峰 吕拴录

YU Shijie YUAN Pengbin WEI Liming LIU Xianwen GAO Jianfeng LV Shuanlu

上海海隆石油管材研究所，上海　200949 渤海钻探公司钻井技术服务公司，天津　300280 中国石油大学，北京　102249

Shanghai Hailong Oil Tubular Goods Research Institute, Shanghai 200949, China The Well Control Center of Bohai DrillingTechnology Services Company, Tianjin 300280, China China University of Petroleum, Beijing 102249, China

某油田先后出现多起钻杆接头螺纹粘扣事故，且都为新钻杆，给油田造成了较大的经济损失。为了避免此类事故的再次发生，结合现场调查，通过对钻杆粘扣的接头螺纹形貌进行宏观观察，及对接头材料的力学性能、化学成分、金相组织进行了全面的试验分析。结果表明，该次螺纹大面积粘扣与接头材质无关，而是井队在接立柱过程中，立柱中心轴线与入井钻杆轴线同心度偏差较大，在螺纹旋合时引起偏斜对扣，造成接头螺纹碰伤，以及高速引扣，引起公母螺纹牙齿相互干涉，造成螺纹面的挤压磨损，塑性变形，最终导致大面积的接头粘扣。最后根据失效原因，提出了相对应的改进措施和建议。

A number of drill pipe joint thread-galling failures were discovered in the oil field mentioned, and all of them happened on new pipes, which brings a big loss to oil field economy. Field survey was applied to the failure accident. Mechanical properties test, chemical composition analysis, and micro-structure examination to the joint material and the macro-appearance observation to the tool joint threads were taken. The results showed that, as there was a great central axis deviation of the stands in picking-up process, which caused mechanical damage to the joint threads when make-up, and as the guiding process to make-up was in high speed, the thread galling of tool joints happened eventually. In the end, the prevention methods and suggestions were put forward based on the failure cause.