钻杆焊缝侧弯试验样断裂原因分析  

Analysis of Causes for Fracture of Specimen for Side-bend Test to Drill Pipe Weld

作　　者：余世杰[1] 徐昌学 陈猛[1] 欧阳志英[1] YU Shijie;XU Changxue;CHEN Meng;OUYANG Zhiying(Shanghai Hilong Oil Tubular Goods Research Institute,Shanghai 200949,China)

机构地区：[1]上海海隆石油管材研究所,上海200949

出　　处：《钢管》2021年第2期63-67,共5页Steel Pipe

摘　　要：钻杆焊缝灰斑缺陷是影响钻杆焊缝性能稳定性的关键因素。分析钻杆摩擦焊接侧弯试验样品断口发现样品断口和冲击断口都表现为明显的脆性断口形貌,分析其产生的主要原因是原料管端部存在的大量夹杂物在摩擦焊接过程中未被挤压出焊缝,在焊缝局部区域形成灰斑缺陷,降低了焊接接合面的强度;建议在钻杆焊接前应彻底清除管体与接头焊接端面上的污渍,确保焊接两端母材的洁净度,适当提高摩擦焊接时的顶段压力,保证焊缝轴向缩短量,使氧化了的金属尽可能以飞边形式排出焊缝,以减少焊区内微观灰斑的产生。The weld gray spot acts as a key factor affecting performance consistency of the drill pipe weld.The fracture of the side-bend test specimen of the friction-welded drill pipe is analyzed.As a result,it is identified that both the specimen fracture and the impact fracture obviously present as the brittle fracture morphology.Accordingly the causes are analyzed,and the main cause is found,i.e.,the large amount of inclusions as existing in the end section of the blank pipe which have not been extruded out of the weld during the friction welding process,and then turn into defects as the gray spots locally distributed in the area of the weld,which reduces the strength of the welding joint face.Therefore it is suggested to fully clean up any dirt on the welding end faces of the pipe body and the joint for assuring of the cleanness of the base metals of the ends to be welded,and to properly increase the top section pressure during the friction welding for assuring of the weld axial shortening amount so as to get the oxidized metal excluded out of the weld in the form of fin as far as possibly in a bid to reduce the occurrence of the micro-gray spot in the welding area.

关 键 词：钻杆 摩擦焊 焊缝 缺陷 焊接灰斑 失效分析 

分 类 号：TE921.2[石油与天然气工程—石油机械设备]