Abstract: Apparatus for laying and/or retrieving elongate flexible elements, such as pipes and cables having accessories at spaced intervals, is mounted on a floating vessel such as a barge an comprises two self powered conveyors pivotally connected together through a hinge but which may be locked relative to one another for use. A trolley runs on wheels or rails on either side of the conveyor system and has an upper surface consisting of a further powered conveyor. The sides of the conveyor extend to form a chute at the outboard end. In normal operation the trolley is stored and the pipe or cable is carried by the conveyors to the chute which guides it into the water. The shape of the chute permits the pipe/cable to leave the barge at up to 45 degrees either side of the fore and aft axis of the conveyor.

Abstract: A method, using a crane-equipped depot ship, for automatically repairing an underwater pipeline even if installed at great depth, comprising substantially the following steps: cutting off the damaged pipe piece by a single working module which, lowered onto the sea bed by a crane and clamped about said pipeline, removably supports the cutting apparatus; removing the concrete from the facing ends of the cut pipeline by said single working module which removably supports the removal apparatus, this being provided with an expansion-centering head; installing connectors by a sonar head alignment apparatus removably supported by said working module; and installing the replacement pipe piece by said working module using a reference and guide apparatus clamped about said ends of the pipeline. Specific apparatus for implementing the method are also described.

Abstract: A device for depositing and recovering a heavy load on the ocean floor including a first part which can be attached mechanically to a handling and recovery cable and a second part which can be attached mechanically to the load to be deposited. The second part is buoyant and includes means for attaching it flexibly to the load. Each of the two parts include a cylindrical joining element, one of which fits inside the other. The device also includes means for locking and unlocking the cylindrical joining elements.

Abstract: A marine cable retrieval apparatus for retrieving marine seismic cable on board a ship which reduces longitudinal tension force on the cable at the cable storage reel when the cable storage reel (drum) is winding up the cable. Marine cable is subject to a tension force which can damage the marine cable when it is placed on a storage reel. The apparatus of this application reduces the tension on a portion of marine cable so that the portion can be retrieved upon a storage reel. The apparatus includes a collar attached to the marine cable and a cable retrievel tool which is placed around the marine cable. The cable retrieval tool has a biasing mechanism which will allow the tool to pass over the collar attached to the marine cable when it is moving away from the ship, but when it is moving toward the ship the biasing mechanism will engage the collar. The cable retrieval tool exerts an opposing force on the collar to the longitudinal tension force on marine cable trailing behind the collar.

Abstract: A clamp is disclosed which is capable of latching on to a buckle arrestor on a subsea pipeline which has been severed in the vicinity of the buckle arrestor. By severing the pipe in this location and utilizing the buckle arrestor to latch the clamp on to the pipe, a simple and reliable clamp is used. A method to recover such a subsea pipeline by severing the pipeline in the vicinity of the buckle arrestor and utilizing such a clamp is also disclosed.

Abstract: A pipelay apparatus and method comprising a steel turntable and a stinger pipe guide which can be supported on the construction deck of a repair vessel or drill ship are provided. The turntable is framed so that loads from two hanging pipes can be securely supported. The table-supported framing members can be moved so the load centerline for each pipeline can be placed an appropriate distance from the center of turntable rotation, which is useful where the two pipelines are of different diameters. This apparatus permits a vessel to simultaneously handle different sizes of pipe and pass large diameter appurtenances without modifying the stinger pipe guide.

Abstract: A method for severing and recovering a submerged pipeline is disclosed. The severing and recovering operation may be performed with divers or with a remotely operated vehicle. The deflated lift bag is lowered to the submerged pipeline. The deflated lift bag is positioned under the submerged pipeline and then inflated until a section of the pipeline has been raised off of the sea floor. A cutoff saw is next lowered to the raised section of the pipeline. The cutoff saw is clamped to the pipeline prior to severing the pipeline. The cutoff saw is then removed from the severed pipeline. A recovery head is lowered to the raised end of the severed pipeline. The recovery head is aligned and placed in the raised end of the severed pipeline. The recovery head is activated to establish a gripping relationship with the pipeline. A recovery cable is lowered and connected to the recovery head. The recovery cable is retrieved to recover the recovery head and the pipeline to the water surface.

Abstract: Vessel carried apparatus for laying a continuous metal pipe on the bottom of a body of water comprising a pipe overbending structure mounted on the end of a vessel and having a 90 degree arcuate peripheral configuration in a vertical plane extending from the water to a position overlying the vessel. Pipe engagable rollers are disposed along the arcuate periphery of the overbending structure, and an arcuate track parallel to the arcuate periphery is formed on the overbending structure. A stinger frame carries two longitudinally spaced pipe bending roller means respectively engaging the top and bottom surfaces of a continuous linear pipe formed on the vessel. The first such roller means bends the pipe to conform to a selected extent of the pipe engagable rollers, while the second roller means reversely bends the pipe to a linear configuration. The forward end of the stinger frame is horizontally pivoted to a carriage which is lockable in any selected position along the arcuate track.

Abstract: A method of locally supplying slack to an axially tensioned length of pipeline spanning unsupported across an undulating seabed. During pipeline deployment, the pipeline is fitted with two weighted masses that will be positioned on either side of the undulation to be spanned. These masses will be spaced a predetermined distance from each other along the seabed, this distance being less than that between them along the pipeline. Also during deployment, the mid-region of this span is vertically deflected upward while retaining the axial tension in the pipeline. Once the pipeline is properly positioned, the vertical deflection of the pipeline is reduced thereby relieving the axial tension in the pipeline while also introducing sufficient pipeline slack such that the pipeline can closely follow the contours of the undulating seabed.

Abstract: A clamp for gripping an electrical cable for the purpose of raising the cable from, or for lowering it into, the water. The clamp comprises a plurality of clamping units which are disposed in series in the direction of the length of the cable and which are held together by a pair of flexible wire ropes in a manner which permits them to articulate with respect to each other. Each unit comprises a pair of jaws for receiving the cable therebetween, and the jaws are urged against the cable by adjustable screws acting through springs to press the jaws toward each other.

Abstract: Apparatus for preventing flow of water from a first underwater pipeline portion forward of the apparatus to a second underwater pipeline portion rearward of the apparatus. At least one wedge-shaped member is mounted on a carriage of the apparatus for grippingly engaging the internal wall of a pipeline for preventing movement of the apparatus in a rearwardly direction upon application of force to the carriage urging the carriage in a rearwardly direction in the pipeline. In order to provide frictional contact with the pipeline wall so that gripping engagement thereof may be effected, the member is continually urged into sliding engagement with the pipeline wall during movement of the apparatus through the pipeline in a forwardly direction.

Abstract: An eccentric hinge is provided for laying submarine pipelines which facilitates joining long segments of the pipeline by raising adjacent ends of the segments, attaching the hinge thereto, and lowering the segments and hinge to the sea-floor while remotely applying tension to one of the segments.

Abstract: An apparatus is disclosed which is employable by a remotely controlled unwater work system to emplace a lift sling beneath an object resting on mud, sand or the like. The apparatus includes a hollow tube and a guide having rollers through which the tube may be passed. The rearward end of the tube is attached to a hose through which water under pressure is directed into the tube. The forward end of the tube is provided with a nozzle so that jets of water issue from it with selected strength and in a selected configuration. A sling or strap is connected at one end to the nozzle end of the tube and at its other end to the guide. A rope or cord is also attached to the guide portion of the apparatus. A mechanical grabber or other mechanism holds the guide in a fixed position with respect to the object to be retrieved while a manipulator arm of the system pushes the tube through the guide and beneath the object to be salvaged.

Abstract: A method and apparatus for the remote recovery of submerged pipelines is disclosed. The operations are entirely controlled by an operator located on a lay barge or other floating vessel. A buoy and cables are manipulated from the lay barge to deploy equipment to a submerged pipeline. To utilize the invention, an alignment cable is threaded through a pipe alignment frame and is then connected to a buoy. The pipe alignment frame is lowered by the alignment cable into an operational relationship with the submerged pipeline. Once the pipe alignment frame is in an operational relationship with the submerged pipeline, the alignment cable is slackened and the buoy and attached alignment cable rise to the water surface. Cutting equipment connected to a retrieval cable is connected to the alignment cable. The cutting equipment is lowered to a predetermined location relative to the pipe alignment frame and attached pipeline by taking in the alignment cable while paying out the retrieval cable.

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: Method and apparatus for recovering a length of an electric cable from great depths of water in which a first device with a buoyancy tank and cable gripping jaws is lowered into the water and guided into position over the cable by an operator controlled submarine having manipulating arms. The tank is then released from the remaining equipment and rises to the water surface letting out a rope secured at its lower end to the remaining equipment. The operator then operates the jaws into gripping engagement with the cable. Thereafter, the rope is secured to a tensioning line on a surface ship, and a second device is lowered by the ship along the rope so as to settle in the remaining equipment, the latter being formed to fit into and with a cage at the bottom of the second device. The second device has a plurality of articulated clamping jaws which the operator operates into gripping engagement with the cable, and by raising the second device from the ship, a length of the cable is brought to the water surface.

Abstract: The invention relates in improvement in or relating to a stand-by service structure for casual off-shore attendance. The service structure comprises an emergent articulated column pivotally connected with its submerged bottom end to a base member resting on the sea-bed. Said column is fitted with a base member module such as a base member with a workshop caisson comprising at least one opening giving access to the sea-bed and adapted to be closed in fluid-tight relationship. Furthermore, said workshop caisson is adapted to directly communicate at least temporarily with the outer atmosphere at the water surface.

Abstract: A method of recovering an underwater pipe comprises inserting a recovery line attachment into the pipe, explosively deforming the pipe so that it is mechanically secured to the attachment, and bringing the pipe to the surface by means of a lifting line secured to the attachment. The attachment may include a body insertable into the end of the pipe and a portion having a generally conical surface so that it forms a water tight seal with the pipe when the pipe is explosively deformed into engagement with it.

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: A system of submarine cranes suited to handling pipe, fittings, tools and machinery on the marine floor, as by divers, and having simple articulate carrying crossbeams with hydraulic motive means and controls, and possible balloon assistance and means to hump and bend, couple, and repair pipelines and machines under water.

Abstract: A diverless subsea flowline connection system includes connectors for remotely connecting the ends of a first bundle of flowlines to the ends of a second bundle of flowlines and guidance components which direct the end portions of the first bundle of flowlines into precise connecting alignment with the end portions of the second bundle of flowlines without damage to the connecting seals. The ends of the first bundle are covered and sealed so that the flowlines can be pulled across the seafloor without damage to the ends of the flowlines. Means are provided for pulling the first bundle toward an alignment structure so that the lines can approach the structure from a wide variety of angles and the structure will guide the first bundle into exact alignment with the second bundle. This pulling means includes means for connecting a pulling cable to the radial center of a pulling head attached to the ends of the first bundle of flowlines.

Abstract: A pipe laying vessel has a hoisting winch whose cable is connected to an underwater pipeline during abandonment and recovering operations by a shock absorbing device inserted into and connected to the free end of the pipeline. The shock absorbing device includes a pre-pressurized hydraulic accumulator which is hydraulically coupled to a cylinder and piston, the piston being connected to the hoisting cable with shock loading due to wave action on the vessel being converted to movement of the piston in the cylinder and against pressure of the accumulator.

Abstract: A system of submarine cranes suited to handling pipe, fittings, tools and machinery on the marine floor, as by divers, and having simple articulate carrying crossbeams with hydraulic motive means and controls, and possible balloon assistance and means to hump and bend, couple, and repair pipelines and machines under water.