长输管道在线焊接关键技术探讨

Discussion on Key Technology of On-Line Welding for Long Distance Pipeline

因管体缺陷、腐蚀和第三方施工,管道极易发生油气泄漏事故。管道在线焊接是管道应急抢修的关键技术环节,高钢级、大口径、高压力的特点对管道在线焊接工艺和质量提出了更高要求。通过调研国内高钢级管道在线焊接的风险因素和瓶颈问题,阐述了焊缝产生氢致裂纹的原因机理和预防措施。研究了影响管道在线焊接质量的关键因素,包括环境条件、管道壁厚及压力、焊接工艺、焊前预热和焊后热处理保温等。介绍了国外最新的管道在线焊接研究成果和实践做法,对于保证管道焊接质量和提高管道抢修技术水平具有重要意义。

Due to pipe defects,corrosion and third party construction,the pipeline is prone to oil and gas leakage accidents.Pipeline online welding is the key technical link of pipeline emergency repair.The characteristics of high steel grade,large diameter and high pressure put forward higher requirements for pipeline online welding process and quality.By investigating the risk factors and bottle-neck problems of domestic high steel grade pipeline online welding,this paper firstly expounds the cause mechanism and prevention measures of hydrogen crack in weld,and then studies the key factors influencing the online pipeline welding quality,which include environmental conditions,pipe wall thickness and pressure,welding process,preheating before welding,heat treatment and insulation after welding etc.and finally introduces the latest research results and practice of online pipeline welding abroad,which is of great significance for ensuring the quality of pipeline welding and improving the technical level of pipeline emergency repair.