海底管道不停输带压开孔封堵技术应用

Application of hot tapping and stoppling technology for subsea pipeline

海底管道水下带压开孔、封堵是一种在役管道维抢修技术,适用于管道的正常维修改造和突发事故的抢修。渤海某D12 in天然气管道在内检测时发生卡球情况,在正向增压和反向泄压均无效的情况下设计了不停输带压开孔封堵的方案。介绍了带压封堵施工的全过程,包括:管道的挖沟暴露、混凝土层清理、开孔封堵设备的安装以及开孔封堵作业、管道切割取智能球、管段回接等。并介绍了关键技术:首次使用国产机械三通、国产高压软管作为临时旁通、开孔机与机械三通组合体的水下竖直安装。此次海底管道不停输带压开孔封堵技术的应用,填补了国内该领域的空白,在确保管道生产的同时,减小了维修作业时管道大量进水及溢油的风险。

Hot tapping and stoppling is a kind of maintenance technology for pipeline in service, which is suitable for normal maintenance and renovation of pipelines and emergency repair in sudden accidents. The pig was stuck in a D 12 inch natural gas pipeline in Bohai during the pipeline internal detection. The measures of forward pressure increase and backward pressure drop were adopted to solve the problem, but failed. Therefore, the scheme of using hot tapping and stoppling technology was designed. In this paper, the whole process of hot tapping and stopple is introduced, including trenching to expose pipeline, cleaning concrete layer, installation and operation of hot tapping and stoppling equipment, cutting pipe to take out the pig and pipe connection; The key techniques are described, including the first use of domestic mechanical tee junction and high-pressure hose as temporary bypass, and underwater vertical installation of integral pipe tapping machine and tee junction. The successful application of the hot tapping and stoppling technology in the subsea pipeline fills the gap in the domestic relevant field, and reduces the risks of large quantities of water entering and oil spilling during pipeline maintenance while ensuring pipeline production.