压力容器2023，Vol.40Issue(10)：9-16,27,9.DOI:10.3969/j.issn.1001-4837.2023.10.002
基于全尺寸试验的管道凹陷回弹回圆行为研究
Research on spring-back and re-rounding of pipe dent based on full-size tests
摘要
Abstract
Spring-back and re-rounding directly affect the depth and stress-strain state of the dent.In order to understand the influence of dent spring-back and re-rounding behavior on pipeline structural integrity,and establish the correction coefficient of spring-back and re-rounding of the dent so as to estimate the maximum depth of non-restrained dent when the dent is formed and the minimum depth of spring-back and re-rounding after removing the constraint reported by ILI.Full-size tests of spring-back and re-rounding of the X70 spiral steel pipe with two pipe diameters and three wall thicknesses were carried out.The results show that the spring-back and re-rounding of the dents are affected by many factors,such as pipe diameter-thickness ratio,indenter shape and size,dent location and depth.The average spring-back ratio is 23%and the maximum reaches 38.4%under zero internal pressure;the average re-rounding ratio is 29.6%and the maximum reaches 49.6%under internal pressure(50%SMYS circumferential stress level);and the comprehensive spring-back and re-rounding ratio in te whole process of dent forming exceeds 54.6%,which leads to the big difference between dent evaluation results under different constraint conditions.The nonlinear regression method was used to fit the empirical formula of the coefficient of spring-back and re-rounding.The error analysis shows that the fitting prediction accuracy is relatively high,which can satisfy the dent peak depth estimation before or after spring-back and re-rounding,and can evaluate the structure integrity of pipeline with dents more accurately.关键词
管道/凹陷/回弹/回圆/全尺寸试验/非线性回归Key words
pipeline/dent/spring-back/re-rounding/full-size test/nonlinear regression分类
机械制造引用本文复制引用
王富祥,杨辉,臧红,张宁..基于全尺寸试验的管道凹陷回弹回圆行为研究[J].压力容器,2023,40(10):9-16,27,9.基金项目
国家管网集团科学技术研究总院科学研究与技术开发项目(ZYZL-AQWH-202206) （ZYZL-AQWH-202206）
国家管网集团北方管道有限责任公司科学研究与技术开发项目(20210207) （20210207）
