X70钢高压输气管线在役焊接剩余强度尺寸效应数值模拟  

Numerical simulation of residual strength size effect of X70 steel high pressure gas pipeline in-service welding

作　　者：郭广飞[1,2] 王勇[2] 韩涛[2] 

机构地区：[1]合肥通用机械研究院国家压力容器与管道安全工程技术研究中心,合肥230031 [2]中国石油大学(华东)机电工程学院,青岛266580

出　　处：《焊接学报》2016年第9期110-114,133-134,共5页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51074174);山东省自然科学基金资助项目(ZR2010EM041)

摘　　要：通过X70钢高温拉伸试验与SYSWELD数值模拟相结合的方法,对X70钢高压天然气管线在役焊接的剩余强度尺寸效应进行了研究.试验表明,700℃时,X70钢屈服强度为250 MPa,800℃时降为102 MPa,从800℃增至1 300℃进行拉伸,屈服强度非线性降至19 MPa.使用等效缺陷法、有限元计算结果及X70钢的高温拉伸数据,对在役焊接管道的剩余强度进行了评价.结果表明,当等效缺陷面积增加到原面积的1.1倍时,管道的承载能力从3.38 MPa下降到0.5 MPa;熔池长度对剩余强度的影响较小,熔池深度以及熔池宽度对剩余强度影响较大,剩余强度的分布更大程度受到熔池深度的影响,表现出明显的熔池尺寸效应.The X70 pipeline steel high temperature tensile test and simulation that based on the welding software of SYSWELD were used to study the in service welding residual strength size effect. The results of tensile test showed that,when the temperature was 700 ℃,the strength of X70 pipeline steel was 250 MPa,when the temperature rised from 800 ℃ to 1 300℃,the strength reduced nonlinearly from 102 MPa to 19 MPa.The equivalent method of defect,the numerical simulation results and the high temperature mechanical properties research data were combined to establish residual strength burn through criterion of in service welding,and the influence of the pool size effect to the criterion was also be studied,when the area of the equivalent defect increased to 1. 1 times the bearing capacity decreased from 3. 38 MPa to 0. 5 MPa,which showed that the bearing capacity was decreased significantly with a slightly increase of molten pool area,the pool length had little effect on the residual strength,the pool depth and pool width have significant effect on the residual strength,and the change of penetration has a greater effect on the strength distribution of the high temperature area,the pool size effect is obvious.

关 键 词：在役焊接 天然气管线 剩余强度 尺寸效应 高温拉伸 

分 类 号：TG402[金属学及工艺—焊接]