天然气管道动火连头施工难点及对策  

Difficulties of Welding Construction in Natural Gas Pipeline Connection and Countermeasures

作　　者：李国民[1] 卢双臣 颜腊红 李斌[1] 

机构地区：[1]中国石油冀东油田公司,河北唐山063209

出　　处：《石油工程建设》2015年第6期60-62,共3页Petroleum Engineering Construction

摘　　要：由于天然气具有易燃易爆等特点,因此对新老天然气管道系统进行动火连头作业就比较危险。结合某湿气管道改造工程,介绍了首次采用具有易于操作、安全可靠、施工成本低等特点的蒸汽吹扫、加装隔离法兰、黄油墙封堵等技术措施,切实做到了在动火连头作业中消除轻烃,隔绝可燃气体,保证了施工作业安全;较详细论述了工程难点,动火连头方案的确定,以及停产降压、氮气置换、蒸汽吹扫、气体检测、黄油墙封堵、法兰焊接、石棉板隔离、管道焊接、无损检测等的施工步骤。工程实践表明,采用上述方案进行施工效果良好;同时也指出了对于短距离湿气管道,采用蒸汽进行吹扫的效果较好,对于长距离天然气管道,宜采用清管扫线方式清除轻烃。Because natural gas is flammable and explosive, the risk related to welding operation for connecting old and new gas pipelines is relatively high. Combined with the reformation project of a wet gas pipeline, this paper summarizes some easily operational, safe, reliable and cost-saving technical measures, such as steam purging, installing isolated flange and blocking with butter wall, to eliminate light hydrocarbon and isolate flammable gas. It illustrates the project difficulties, welding scheme determination, and the construction process including production stop and pressure decreasing, nitrogen replacement, steam surging, gas de- tection, blocking with butter wall, flange welding, insolating with asbestos plate, pipeline welding and NDT. The construction practice shows these measures get good effects, the steam purging can gain better effect for short distance wet gas pipeline and the pigging mode to clean light hydrocarbon is suitable for long distance pipeline.

关 键 词：天然气管道 动火连头 蒸汽吹扫 法兰隔离 黄油墙封堵 

分 类 号：TE973[石油与天然气工程—石油机械设备]