Route Selecting And Pipeline Laying During Subsea Pipeline Route Modification And Reconnection Technique

During the offshore oil drilling engineering, the subsea pipelines make the offshore oil/gas field, FPSO or terminal onshore to become integrated, make the offshore production facilities become a related and harmonious operation systems. Subsea pipeline is the aorta of oil/gas production system to all the offshore oil/gas fields. The net project is very important to the technique, economic and production system of the field development.As the offshore oil/gas fields'developing, the pipeline transportation has been widely used during offshore oil. In the North Sea, long distance oil/gas pipelines have been built up, which promotes the development of huge gas field. In Mexico Bay, the subsea pipelines, of which the total length is 37000km, connect the oil/gas fields and terminals to be a system of production, management and market. The normal running of subsea pipelines is the key factor of oil exploitation in Mexico BayDuring 20 years of offshore oil exploitation in our country, 2500km subsea pipelines have been built up, which include in-field oil/gas/water pipelines, water injection pipelines and long distance gas/oil pipelines. The pipe-in-pipe pipeline is about 350km long, the normal pipeline is about 2100km long and the flexible pipeline is about 20km long. So far, the longest subsea gas pipeline is about 800km long.This paper introduces the technique during design and construction of subsea pipeline, which includes route select and detection, analysis and design of stability and strength on seabed, exceptive loads, obstruction crossing and subsea pipeline installation. At the same time, take Jinzhou Port Channel Crossed Subsea Pipeline Modification Project as the engineering example.