Offshore pipeline construction. Part 1. Offshore line construction methods examined

The most common offshore pipeline-construction methods currently in use are the lay-barge, reel-barge, and pull systems. Lay barges install the vast majority of offshore lines, although the pull method is the most suitable for crossing narrow, deepwater channels. Basically a variation of the lay-barge system, the reel-barge technique is less expensive and faster but limited to flexible pipe no larger than 4 in. in diameter.