Study Of Residual Strength For The Corroded Pipeline Base On Finite Element Analysis

Our country’s petroleum buried pipe line already entered the high stadium, theperforation accident occurs repeatedly.Is affecting the petroleum transport and creates themassive loss to the economy, the pipeline surplus intensity research is a important basis forthe direct judgment buried pipe line whether damages. It is the most important solutionquestion for the pipeline safe operation.This article unifies the buried pipeline corrosion present situation of the oil recoverplant NO.6of Da qing, through the macroscopic analysis, the material quality analysis, themicrostructure analysis, degree of hardness test and the corrosion product microscopicappearance, the microscopic ingredient and the XRD analysis and so on, studied haswatered the pipeline eclipse mechanism.Using finite element method simulator study flatbase square shape, with bottom square shape, ellipse, sphere etch pit and combinationcorrosion flaw to expiration influence.Has carried on in the corrosion flaw pipeline surplusintensity room the modelling, has confirmed the finite element analysis method reliability,and developed in this foundation corroded the pipeline surplus intensity appraisal software.The result indicated that, erosion resistant coating of the pipeline of the oil recoverplant NO.6was destruction, causes in the stratum the dampness penetration to the bodyoutside surface, in the water dissolved oxygen with to water the pipeline outside surfacematerial to affect mutually has the corrosion, forms not the compact corrosion product level（Fe₂O₃）, finally causes to the pipeline destruction.Regarding the flat base square shape flaw, the length marginal value is150mm, thewidth marginal value is10mm, regarding with the bottom square shape flaw, the lengthmarginal value is120mm, the width marginal value is40degrees, regarding the sphere etchpit flaw, the aperture marginal value is pitting depth2mm, the depth of hole marginal valueis pitting depth1.5mm.In corrosion flaw pipeline surplus intensity room modelling resultand finite element analogue result close （biggest error8.6%）, has confirmed limited methodthe accuracy, the development corrosion pipeline surplus intensity appraisalsoftware.Operates simply, the computing time is short, it has certain practical value.