Abstract: A method and apparatus for simultaneously digging a trench in the bottom of a body of water and laying a pipe from a barge therein. The plow is provided with vertical side plates to assist in molding the side of the cut trench so an inclined ramp can move the soil upwardly where it is diverted to each side of the trench. The pipe being laid is extended from a working barge through a hiatus at the aft end of the trenching device. The position of the pipe in the hiatus is monitored and that information is used to properly position the barge with respect to the trenching machine. In one embodiment a gas/oil spring supports the lower horizontal roller at the bottom of the hiatus.

Abstract: An apparatus for straightening pipe unwound from and at a point on a reel aboard a floating barge which has a stern and a stern roller supported by the barge. Tensioning means on the barge for applying tension to the pipe as it is unwound from the reel. The stern roller and the point on the reel defining a straight, tangent line with one and only one straightening roller member between the stern roller and the point on the reel. The barge has support means supporting the straightening roller member above the tangent line.

Abstract: A marine continuous pipe laying system comprising a variable departure angle reel operably connected to a retractable trenching plow and backfilling apparatus. The reel comprises a pipe straightening mechanism connected to the rotational axis of the reel by a yoke for automatically maintaining proper bending moment regardless of the departure angle of the pipe. The plow comprises a shaped chisel share which is pivotally retractable within a sled frame for avoiding existing pipelines and varying the depth of cut and is provided with instrumented guide rollers to permit an operator to adjust the tow length of the plow to properly position the plow with respect to the catenary curve of the pipe being laid. The distance between the plow and the backfilling apparatus is adjustable to insure that the pipe is in the bottom of the trench before backfilling occurs.