脉冲电流修复高压管汇弯头裂纹有限元模拟  

Finite element simulation on crack repair of high pressure manifold elbow by pulse current

作　　者：梁玉恒 张思[1] 占凯 徐昊 LIANG Yuheng;ZHANG Si;ZHAN Kai;XU Hao(School of Mechanical Engineering,Yangtze University)

机构地区：[1]长江大学机械工程学院

出　　处：《油气储运》2023年第4期422-429,共8页Oil & Gas Storage and Transportation

基　　金：国家自然科学基金资助项目“计算压裂泵头体寿命的‘无形边界’新方法”,52174018;中国高校产学研创新基金资助项目“‘虚实结合’实践教学模式在石油机械专业的应用研究”,2019ITA04001。

摘　　要：为探究脉冲电流对弯头热加工成型后产生微小裂纹的修复趋势,研究弯头热加工成型时产生的微小裂纹分布,利用电-热-结构三场耦合的方法,探究了脉冲电流修复裂纹的机制,并对不同电压和不同裂纹角度下脉冲电流对裂纹修复效果的影响规律进行了研究。结果表明:由于电流在裂纹缺口处产生绕流,裂纹尖端存在电流聚集效应,产生高温和热压缩应力,从而使裂纹有愈合趋势;电压对弯头的修复趋势具有影响,当电压小于65 V时,电压越高,裂尖的温度和残余压应力越高,裂纹的愈合效果越好。裂纹角度越大,脉冲电流对裂纹的愈合效果越明显,其中裂纹初始角度为0°时愈合效果最弱,裂纹初始角度为90°时愈合效果最明显。研究成果为脉冲电流修复技术在高压弯管中的应用奠定了理论基础,对提高高压弯头强度、保障油气安全生产具有重要意义。(图12,表2,参21)In order to explore the repair trend of tiny cracks generated after elbow forming by hot working with pulse current,the distribution of tiny cracks generated during elbow forming by hot working was studied,and the mechanism of crack repair by pulse current was explored using the method of electro-thermal-structural coupling.Besides,the effect of pulse current on crack repair under different voltages and crack angles was also studied.As shown in the results,the current gathers at the crack tip due to the bypass current at the crack notch,which generates high temperature and thermal compressive stress for the healing trend of cracks.In addition,the repair trend of elbow is affected by the voltage.When the voltage is less than 65 V,the higher the voltage,the greater the temperature and residual compressive stress at the crack tip,and the better the healing effect of crack.The healing effect of crack by pulse current becomes more obvious at the increasing crack angle.Specifically,the healing effect is the weakest for the 0°crack distribution and the most obvious for 90°crack distribution.Generally,the research results lay a theoretical foundation for the application of pulse current repair technology in high pressure elbow,which is of great significance for improving the strength of high pressure elbow and ensuring the safety of oil and gas production.(12 Figures,2 Tables,21 References)

关 键 词：脉冲电流 裂纹修复 弯头 热加工成型 绕流 

分 类 号：TH17[机械工程—机械制造及自动化]