摘要
依据英国标准BS 7910对海底外输管线API5L X56焊接接头焊趾处表面裂纹进行了ECA(engineering critical assessm ent)评定。评定根据母材和全焊缝拉伸试验结果建立评定曲线;根据英国标准BS 7448:Part 4采用多试样方法进行了低温断裂韧度试验,建立了焊缝和HAZ的CTOD-R阻力曲线,从而确定了启裂CTOD值0δ.2。在评定计算中取不同水深的应力最大值,分别考虑应力集中和残余应力的影响,针对无错位和最大错位情况,给出了在铺设条件下的容许表面裂纹尺寸。为管线铺设工程中的焊接缺陷验收和拒收提供了依据。
British standard 7910 was applied to engineering critical assessment for welded joints of the API5L X56 pipeline steel with surface flaw at the weld toe.The failure assessment diagrams were derived from the tensile test results.In accordance with the BS 7448 Part 4,fracture toughness test standard,δ-Resistance curve tests were conducted with multiple specimens at(5℃) in welded joints of X56 pipeline steel.And then the δ_(0.2)values of weld and HAZ were obtained.The assessment was carried out by using the maximum stress at different water depth,and the stress concentration and residual stress were also considered.The tolerable surface flaw sizes were gained at perfect alignment and maximum allowable misalignment.This study lays the foundation for judging the acceptability of flaws.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2006年第1期17-20,25,共5页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(50375109)
中国海洋石油工程股份有限公司资助项目
关键词
英国标准
容许尺寸
工程临界评估ECA
British standard
tolerable size
engineering critical assessment
