易燃易爆工艺管线焊接缺陷安全评定——上海石化总厂工艺管线的安全评定及其缺陷的返修技术

SAFETY ASSESSMENT FOR COMBUSTIBLE AND EXPLOSIVE CHEMICAL PROCESS PIPELINE CONTAINING WELD DEFECTS

本文以断裂力学为基础,以“合乎使用”为原则并依据流变应力理论,通过有效地解决无损检测,应力分析、缺陷分类及验收准则等方面所遇到的若干技术问题,对管道焊接缺陷进行了安全评定,正确地区分了严重缺陷和非严重缺陷,从而对评定管道焊接缺陷的严重性提出了一种既安全可靠又经济合理的工程处理法。这一方法已被成功地用于上海石化总厂,对其部分在役易燃易爆工艺管线进行了安全评定并解决了超标焊接缺陷的修复问题。

Basing on thd theories of fracture mechanics, 'Fitness for Purpose' and flow stress, this paper conducted safety assessment for pipeline containing weld defects in service by virtue of effectively overcoming a series of technical problems encountered in non-destructive examination, stress analysis, defect classification and acceptance criterion. Thus, serious and non serious defects were accurately distinguished and an engineering approach with safety reliability and economical reasonableness for estimating the seriousness of pipeline containing weld defects was proposed. This new propsed approach has been successfully applied to solve repairing problem of some parts of combustible and explosive chemical process pipelines containing over-size weld defects in service at Shanghai Petro-Chemical Complex.