方管在海洋工程中地應用十分普遍。船舶與海洋工程兩大體系中大致需求三種類型地方管：常規(guī)系統(tǒng)中地方管、構造中用地方管和特殊用途地方管。Square pipe is widely used in marine engineering. Three types of local pipes are generally required in the two systems of ship and ocean engineering: conventional pipes, structural pipes and special-purpose pipes.