随钻适配头断裂失效分析  

Fracture failure analysis of drilling adapter

作　　者：朱玉宁 秦才会[1] 王仡仡 徐志刚 ZHU Yuning;QIN Caihui;WANG Yiyi;XU Zhigang(China Oilfield Services Limited.,Langfang 065000,China;CNOOC(Tianjin)Pipeline Engineering Technology Co.,Ltd.,Tianjin 300450,China)

机构地区：[1]中海油田服务股份有限公司,河北廊坊065000 [2]中海油(天津)管道工程技术有限公司,天津300450

出　　处：《物理测试》2025年第2期43-46,共4页Physics Examination and Testing

摘　　要：某随钻适配头发生断裂后仪器间的供电与通讯中断,起钻后造成经济损失;通过断口宏观形貌分析、微观形貌分析、金相组织分析、化学成分分析、硬度检测来综合确定适配头断裂原因。分析结果表明:适配头为疲劳断裂,疲劳源位于螺纹根部退刀槽与螺纹倒角相接的长条凸台的锐边缺陷处,该处存在较大的局部应力集中,在钻井工作的交变载荷作用下萌生疲劳裂纹并快速扩展;同时固溶+时效处理下的铍青铜材料缺口敏感,晶界弱化,容易形成沿晶裂纹。The power supply and communication between instruments were interrupted when a certain drilling adapter fractured,which caused economic loss after drilling.The fracture cause of the adapter was determined by the analysis of macroscopic morphology,microscopic morphology,metallographic structure,chemical composition and hardness testing.The results showed that the adapter belonged to fatigue fracture.The fatigue source was located at the sharp edge defect of the long strip protrusion at the thread root where the cutting groove and thread chamfer were connected.There was a high local stress concentration at this location,and the fatigue cracks initiated and rapidly expanded under the alternating load of drilling work.In addition,the beryllium bronze material under simultaneous action of solid solution and aging treatment was sensitive to notches,weakening the grain boundaries,which was prone to formation of intergranular cracks.

关 键 词：适配头 疲劳断裂 锐边 缺口敏感 

分 类 号：TG115.2[金属学及工艺—物理冶金]