渤西南海底输气管网联合清管技术

Combined pigging techniques for the subsea gas transmission pipeline network at the Southwest Bohai Bay

渤西南海底输气管网是中国第一个海底输气管网,管网具有距离长、结构复杂、气源多和气质差异大的特点,由于管网节点在海上平台,整体清管难度大,投产以来发生了多次积液和冻堵。为此,针对该管网的特点,分析了管道的沿程温度分布,预测了管道积液量;据此设计了分阶段清管的清管方案,选择了专门研制的泡沫清管球,首次对该管网成功地实施了联合清管作业,共清除积液约170 m3,保障了海底输气管道的安全生产。

The subsea gas transmission pipeline network at the Southwest Bohai Bay is the first of its kind in China.This network's node is located at the offshore platform,its transport distance is long,and its structure is complicated.Besides,it has multiple gas sources composed of different gas components.That is why liquid loading,freezing and plugging accidents occurred frequently since the pipeline network has come on stream.Therefore,this paper analyzed the temperature distribution along the pipeline and predicted the liquid loading volume in the line.On the basis of this,a reasonable pigging program was elaborated and appropriate cleaning pig was selected.A combined pigging operation has been performed for this pipeline network for the first time,and about 170 m3 of liquid loading has been cleaned up as a result.This study is of great significance in the safe production of subsea gas transmission pipeline network.