Abstract: Apparatus for and a method of recovering a submerged pipeline is provided with such apparatus and method being particularly useful with pipelines laid on the bottom of a deep body of water. The apparatus includes support means haivng clamping means thereon for clamping the pipeline and lifting it from its bed, cutter means mounted on the support means for cutting the clamped pipeline to provide a pipeline end, and a recovery header removably mounted to the support. In operation, drive means move the header from its rest position into the clamped and cut pipeline end in an inserted state and retaining means on the support means retain the header in its inserted position. The header and pipeline section are ready for removal. A pulling and guiding flexible cable system from a vessel or barge associated with the apparatus can be used to position the apparatus under water and to move the header with the retained pipeline from the body of water to the vessel.

Abstract: Improved apparatus is provided for forming or erecting concrete loaded supporting means for supporting undersea pipelines at all depths and in the presence of undulating sea beds characterized by providing suspendable service module or frame means provided with pumpable concrete carrying means, vertical articulated positioning arm means mounted at one end to one end of the service module means with the one end thereof having means for releasably engaging concrete receiving pipe support module means, means for actuating the articulated positioning arm to place the support module beneath the undersea pipe to be supported, means operatively associated with the vertical articulated positioning arm and the concrete carrying means for transferring cement from the concrete carrying means to the support module.

Abstract: Apparatus for supporting pipe suspended over depressions in the sea bed and method of, comprising a service modular unit capable of being completely recovered and another modular unit intended for properly supporting the pipe: the two modular units are so connected that they can be disjointed under a command from the pipe-laying barge.The service modular unit is equipped with a recoverable assembly for placing the supporting modular unit in a correct vertical posture on the sea bed and for vertically holding such supporting modular until the pile-driving operation has been satisfactory completed.

Abstract: Method and apparatus for laying an underwater pipe to straddle an already laid pipe, comprising fastening to the pipe to be laid, at appropriate distances apart, a set of trestles the heights of which are gradually increasing and decreasing consistent with the bend to be imparted to the pipe to be laid in order to have it positioned in the correct straddling relationship relative to the already laid pipe. Each trestle is connected to the pipe to be laid by flexible means which allow the trestle to move vertically, longitudinally and traversely relative to the pipe and to be suspended below and separate from the pipe as the pipe and trestle descend to the sea bed for proper positioning of the trestle substantially independent of the pipe.

Abstract: This invention relates to an apparatus for supporting pipes suspended over depressions in the sea bed, including those situated at great depth, and to the method for installing it on the sea bed. The apparatus according to the invention consists of a completely recoverable service module and a support mobile which serves to support the pipe and remains fixed on the sea bed, said modules being connected together in such a manner that they can be separated by simple controls from the depot ship. The method according to the invention comprises in turn a number of operating steps, through which the entire apparatus is initially lowered and positioned on the sea bed and the service module is then recovered by the depot ship.

Abstract: For lifting from deep sea beds a pipeline trunk, a device is disclosed which is composed by a compact framework of square outline which supports a sealing and pulling head and paired jaw assemblies having sloping surface seats to engage the outer surface of the pipe to be lifted, said jaws being actuated by hydraulic and pneumatic motive means so as to grip the pipe surface firmly. A pipe-cutting device is also provided, which has two discrete cutting units, and the sealing and pulling head is removable from said frame and can be both slid and rotated as to position it correctly coaxially with the pipe trunk.

Abstract: An articulated stand apparatus for laying or recovering pipeline in or from a trench dug in the ground wherein the apparatus is hinged to the side of a tracked means or side boom and includes lifting tackle with a hook.The apparatus includes two rigid frames. One frame is hinged at its lower end to the tracked means in such a way that it can be rotated in a plane transverse to the tracked means. The second frame has extensible telescopic elements at its lower end for resting on the ground. The upper ends of the frames are hinged to each other and are disposed in a reversed V with the lifting tackle and hook supported at the vertex of the frames.Extending from the upper end of the second frame is a pair of arms whose ends are hinged to pistons of hydraulic cylinders, which, in turn, are hinged to the center line of the first frame.

Abstract: A self-locking plug, for use in the recovery of a pipeline laid on a deep submerged bed, consists of the combination of a cylindrical body having a rear section for insertion into the submerged end of the pipeline to be recovered and an ogival front end containing an exhaust port, an exhaust pipe extending along the axis of the cylindrical body from its rear end to the exhaust port, an exhaust valve, locking shoes carried by the cylindrical body, a plastic sealing ring carried in an outer groove in the cylindrical body, and means simultaneously actuated by compressed fluid carried in the ogival front end of the cylindrical body to press the locking shoes against the inner wall of the pipeline and fasten the plug to it and to force the sealing ring against the inner wall of the pipeline and prevent the flow of water around the cylindrical body.

Abstract: A pipeline closing head, for use in testing a pipeline after it has been laid on a submerged bed by subjecting the pipeline temporarily to internal pressure through the use of filling and emptying balls, is constituted by a hollow cylindrical body having a crowned closing element at one end and containing, at its other end, an air tight chamber housing the filling and emptying balls. Ducts and control valves through which fluid is supplied to said chamber to activate the filling and emptying balls and supply fluid pressure to the interior of the pipeline are housed within the cylindrical body so that they do not overhang the closing head, which may slide along a conventional ramp for the pipeline.