抽油杆断裂原因  

Reasons for the fracture of the sucker rod

作　　者：陈小琴 杜志杰 李欢 CHEN Xiaoqin;DU Zhijie;LI Huan(China Oilfield Services Co.,Ltd.,Tianjin 300459,China;Xi’an Molar Petroleum Engineering Laboratory Co.,Ltd.,Xi’an 710065,China)

机构地区：[1]中海油田服务股份有限公司,天津300459 [2]西安摩尔石油工程实验室股份有限公司,西安710065

出　　处：《理化检验（物理分册）》2024年第3期45-48,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：某油田抽油杆频繁发生断裂现象。采用宏观观察、化学成分分析、力学性能测试、金相检验、扫描电镜及能谱分析等方法分析了抽油杆断裂的原因。结果表明:该抽油杆的断裂性质为腐蚀疲劳断裂;采用深抽工艺后,抽油杆承受较大的拉伸载荷,增大了抽油杆的平均应力,缩短了抽油杆的疲劳寿命;油井中含有硫化氢,对抽油杆外壁产生腐蚀作用,导致抽油杆外壁产生腐蚀坑,腐蚀坑底部应力集中程度较大,在交变载荷作用下,腐蚀坑底部产生微裂纹,微裂纹不断扩展,最终导致抽油杆断裂。The sucker rod in a certain oilfield frequently fractured.The causes of the fracture of the sucker rod were analyzed using methods such as macroscopic observation,chemical composition analysis,mechanical property testing,metallographic examination,scanning electron microscopy and energy spectrum analysis.The results show that the fracture property of the sucker rod was corrosion fatigue fracture.After adopting deep pumping process,the sucker rod was subjected to a larger tensile load,which increased the average stress of the sucker rod and shortened its fatigue life.The oil well contained hydrogen sulfide,which caused corrosion on the outer wall of the sucker rod,led to the formation of corrosion pits on the outer wall of the sucker rod.The stress concentration at the bottom of the corrosion pit was relatively high.Under the action of alternating loads,micro cracks were generated at the bottom of the corrosion pit,which continuously expanded and ultimately caused the sucker rod to fracture.

关 键 词：抽油杆 断裂 腐蚀疲劳 深抽工艺 

分 类 号：TB31[一般工业技术—材料科学与工程] TE933[石油与天然气工程—石油机械设备]