35CrMo卡瓦连接器断裂原因分析  

Fracture Analysis of 35CrMo Slip Connector

作　　者：刘玉栋 袁少锋 王明元 曹雄 温庆伦 李振金 LIU Yudong;YUAN Shaofeng;WANG Mingyuan;CAO Xiong;WEN Qinglun;LI Zhenjin(CNPC Tubular Goods Research Institute,Xi′an,Shaanxi 710077,China;PetroChina Coalbed Methane Company Limited,Beijing 100028,China;Sulige Project Management Department of Chuanqing Drilling Engineering Company Limited of CNPC,Ordos,Inner Mongolia 017300,China;China National Logging Coporation,Xi′an,Shaanxi 710077,China)

机构地区：[1]中国石油集团工程材料研究院有限公司,陕西西安710077 [2]中石油煤层气有限责任公司,北京100028 [3]中国石油川庆钻探工程有限公司苏里格项目经理部,内蒙古鄂尔多斯017300 [4]中国石油集团测井有限公司,陕西西安710077

出　　处：《石油管材与仪器》2024年第5期85-88,共4页Petroleum Tubular Goods & Instruments

摘　　要：某气井连续油管卡瓦连接器在服役3a后发生了断裂失效。对该失效连接器材料的化学成分、金相组织和力学性能进行了试验,对其断口形貌进行了宏观和微观分析。结果表明,该失效连接器材料的化学成分和拉伸试验结果符合GB/T 3077—2015标准的要求,其材料的硬度和夏比冲击功试验结果不符合GB/T 3077—2015标准的要求。由于失效连接器材料中存在回火马氏体组织,使材料的冲击功试验值低于标准的要求,说明其材料韧性较差;另外,该气井增产时快速旋转流量控制阀门,从而使油管中的液体和气体流量快速增加,因而该连接器所承受的轴向载荷瞬时增大,于是该连接器在轴向冲击载荷作用下发生了脆性断裂。建议气井增产时缓慢旋转流量控制阀门,降低连续油管和连接器在气井增产时所承受的冲击载荷。A coiled tubing slip connector in a gas well broke and failed after 3 years of service.The chemical composition,metallographic structure and mechanical properties of the failed connector material were tested,and the fracture morphology was analyzed at both macroscopic and microscopic levels.The results show that the chemical composition and tensile test results of the failed connector material meet the requirements of GB/T 3077—2015,while the hardness and impact energy test results of the material do not meet the requirements of the standard.Due to the existence of tempered martensitic structure in the failed connector material,the impact energy test value of the material is lower than the standard requirements,indicating that the material toughness is poor.In addition,when the gas well is stimulated,the flow control valve is rapidly rotated,so that the liquid and gas flow rate in the coiled tubing rapidly increases,and the axial load borne by the connector increases instantly,resulting brittle fracture of the connector under the impact axial load.It is recommended to rotate the flow control valve slowly to reduce the impact load of the coiled tubing and connector during the gas well adjustment.

关 键 词：卡瓦连接器 回火马氏体 脆性断裂 

分 类 号：TE931[石油与天然气工程—石油机械设备]