含单纯凹陷的X70管道承压能力评价

Evaluation on pressure bearing capacity of X70 pipeline with pure dent defect

为评价含单纯凹陷的高钢级管道极限承压能力,通过有限元模拟分析了凹陷形成过程及水压试验中钢管的变形情况,并开展了含单纯凹陷管道全尺寸水压爆破试验及应变测试。基于全尺寸试验结果,从含单纯凹陷管道的爆破压力、回弹量及应变变化等方面对有限元分析结果进行了验证。结果表明:高钢级管道凹陷形成过程及水压试验过程的有限元分析与试验结果趋势一致,且误差小于10%,说明对含单纯凹陷管道的模拟是准确的。深度为15.9%D(D为管道外径)的凹陷管道爆破压力为38 MPa,高于理论计算的无缺陷钢管爆破压力(31.2 MPa),说明试验单纯凹陷对管道承压能力未产生不利影响。研究成果为高钢级含凹陷管道的理论分析提供了技术支持。

In order to evaluate the ultimate pressure bearing capacity of high-grade steel pipeline with pure dent defect,finite element analysis was performed for the deformation of steel pipeline during the formation of dent and the hydraulic test.In addition,full-scale hydrostatic burst test and strain test were also conducted for the pipeline with pure dent defect.Based on the full-scale test results,the results of the finite element analysis were verified in terms of burst pressure,rebound behavior and strain of pipeline with pure dent defect.The results show that the finite element analysis results are consistent with the experimental results in both processes of dent formation and hydraulic test,with an error of less than 10%.It indicates that the simulation of the dented pipe is accurate.Besides,the burst pressure of the dented pipe with a depth of 15.9%D(D refers to the outer diameter of pipeline)is 38 MPa,which is higher than the calculated burst pressure,31.2 MPa,of the non-defective steel pipe,indicating that the tested dent has no adverse effect on the pressure bearing capacity of pipeline.The research findings provide technical support to the theoretical analysis of high-grade steel pipeline with dent defect.