φ127 mm钻杆外螺纹接头及焊区部位缩颈失效分析  

Necking Failure Analysis ofφ127 mm Drill Pipe External Thread Joint and Welding Area

作　　者：李亚敏 张然 陈静 王显林 王西华 赵文岩 LI Yamin;ZHANG Ran;CHEN Jing;WANG Xianlin;WANG Xihua;ZHAO Wenyan(Bohai NKK Drill Pipe Co.,Ltd.,Qingxian 062658,China)

机构地区：[1]渤海能克钻杆有限公司,河北青县062658

出　　处：《机械工程师》2022年第10期141-144,共4页Mechanical Engineer

摘　　要：结合钻杆服役工况,通过失效试样宏观形貌分析、磁粉检测分析、理化性能分析,对钻井过程中φ127×9.65 mm钻杆外螺纹接头及焊区部位缩颈失效的原因行了分析。结果表明:钻井过程中岩屑在外螺纹接头35°台肩面附近堆积,随着堆积的岩屑增多,直接堵塞钻井液循环通道。钻井过程中在拉伸和扭转的复合加载下,钻杆外螺纹接头及焊区部位与岩屑之间发生剧烈摩擦,生成的大量摩擦热使得接头及焊区部位温度迅速升高,处于高温部位的材质发生塑性拉长形变,接头外径、内径迅速减小,从而导致钻杆接头及焊区部位出现缩颈失效。Combined with the service condition of drill pipe,through the macro morphology analysis,magnetic particle testing analysis and physical and chemical performance analysis of failed samples,the causes of necking failure of external thread joint and welding area ofφ127×9.65 mm drill pipe are analyzed.The results show that the rock cuttings accumulate near the 35°shoulder surface of the external thread joint during drilling.With the increase of the accumulated rock cuttings,the drilling fluid circulation channel is directly blocked.During the drilling process,under the combined loading of tension and torsion,there is fierce friction between the external thread joint and the welding area of drill pipe with rock cuttings.The generated large amount of friction heat makes the temperature of the joint and the welding area rise rapidly,the material at the high temperature elongates and deforms plastically,and the outer diameter and inner diameter of the joint decrease rapidly,resulting in necking failure of the drill pipe joint and the welding area.

关 键 词：钻杆 缩颈 失效分析 

分 类 号：TD421.2[矿业工程—矿山机电]