For use in the shallow part of the Gulf of Mexico, the cradle of the offshore industry, these barges sufficed. Instead of constructing oil platforms in parts, jackets and decks could be built onshore as modules. The arrival of this type of vessel changed the direction of the offshore construction industry.

Ray McDermott had Derrick Barge Four built, a barge that was outfitted with a revolving crane capable of lifting 150 tons. Their role was to enable the unloading of the Arctic convoys where port installations were either destroyed by German bombers or were non existent (as at Bakaritsa quay Archangel). 'Heavy Lift Ships' SS Empire Elgar (PQ16), SS Empire Bard (PQ15), and SS Empire Purcell (PQ16) were sent to the Russian Arctic ports of Archangel, Murmansk and Molotovsk (since renamed Sererodvinsk). Another remarkable feat was the raising of the submarine USS Squalus in 1939. It was used, amongst other things, to place guns and other heavy items on other battleships under construction. In 1920, the 1898-built battleship USS Kearsarge was converted to a crane ship when a crane with a capacity of 250 tons was installed.

Boat crane lift