
Deepwater generally means greater than 500m, whereas very deep water means 1000m or deeper for offshore pipeline installations. In the area of deep pipelaying, the combination of dynamic positioning and J-lay method is used. In a J-lay method, pipes are laid in a near-vertical position with a specially-designed pipe support tower and a very short stringer. The pipe string is suspended nearly vertical through water depth and bends horizontally in the sagbend strictly adjacent to the seabed. See also Pipelaying methods.