火灾高温下含缺陷管道剩余强度评估  

Residual Strength Assessment of Defective Pipes Under High Temperature in Fire

作　　者：王莉莉[1] 乔宏宇 WANG Lili;QIAO Hongyu(School of Civil and Architectural Engineering,Northeast Petroleum University,Daqing 163318,China)

机构地区：[1]东北石油大学土木建筑工程学院,黑龙江大庆163318

出　　处：《徐州工程学院学报（自然科学版）》2020年第2期55-59,共5页Journal of Xuzhou Institute of Technology(Natural Sciences Edition)

基　　金：大庆市科技计划项目(zd-2016-075)。

摘　　要：为研究火灾高温下含均匀壁厚缺陷的管道应力分布及失效压力变化,以X70管材为研究对象,基于弹塑性力学原理,利用ANSYS软件,模拟其在高温下缺陷局部的等效应力和塑性应变随运行压力的变化,并分析各高温下管道失效压力随缺陷深度、缺陷长度而变化的趋势,进一步讨论了PCORRC法评价高温环境运行下含均匀壁厚缺陷的管道剩余强度的适用性.研究结果表明:缺陷中心等效应力随内压的增大先减后增,低压和高压时缺陷局部应力分布有很大不同;缺陷深度和长度均对失效压力有很大影响,特别地,失效压力与缺陷深度近似呈线性负相关;高温不仅改变了管材的材料属性,引起的热膨胀也将提升缺陷部位的应力状态,减小管道的剩余强度.To study the stress distribution and failure pressure of pipes with uniform wall thickness defect at high temperature.X70 pipe is taken as the research object.Based on the knowledge of elastic-plastic mechanics.ANSYS is used to simulate the variation of equivalent stress and plastic strain of local defects with operating pressure under high temperature,and the variation trend of failure pressure with defect depth and length under various high temperatures is analyzed.Also the applicability of PCORRC method to evaluate residual strength of pipes with uniform wall thickness under high temperature environment is discussed.The results show that the Von Mises stress of the defect center decreases first and then increases with the increase of the internal pressure,and the local stress distribution of the defects is very different at low pressure and high pressure.Both the depth and the length of the defects have a great influence on the failure pressure.In particular,the failure pressure is approximately linearly negative to the depth of the defect.The high temperature not only changes the material property of the pipe,but also increases the stress state of the defective part,thus reducing the residual strength of the pipe.

关 键 词：天然气管道 均匀壁厚缺陷 等效应力 失效压力 PCORRC法 

分 类 号：TE832[石油与天然气工程—油气储运工程]