基于J参量的管道环焊缝表面缺陷塑性撕裂评定

基于英国标准BS7910中的三级评定规程(3C),采用SC.ENG (表面裂纹工程估算方法) J 积分工程估算方法对承受纯弯曲载荷作用的管道环焊缝表面裂纹进行塑性撕裂评定.以X56钢管道环焊缝内表面缺陷为算例,讨论了选用 J 参量进行含缺陷结构的塑性撕裂评定时,裂纹尺寸和断裂评定参量选取对评定曲线及评定结果的影响规律,提出了在J积分评定中选择参量J mat确定评定点较Jg更趋合理.研究内容不仅对管线铺设安全评价具有指导作用,而且对含缺陷结构的塑性撕裂评定在工程上的应用具有推广和借鉴价值.

Ductile tearing assessment of surface flaw in circumferential weld of pipe-line based on J integral parameter

Based on level three programme(ductile tearing assessment) of assessment standard BS7910,ductile tearing assessment of surface flaw in circumferential weld of pipe-line under pure bending load was proceeded by using J integral engineering estimate method of SC.ENG.By taking X56 steel pipeline as an example,effects on assessment curve and evaluating results were given by flaw dimension and fracture parameter choosing were discussed,and the assessment point was put forward that Jmat is more reasonable than Jg in determining assessment points while choosing J integral parameter to make a ductile tearing assessment of flaw in metal structure.The research results are not only taken as a guide on safty evaluation in pipeline construction,but also can make engineering application of the ductile tearing assessment of structure with flaw more popular and referentia.