A transportation platform for an underwater towing device, including: a main frame; a support frame; a movable base; operation decks; ladder stands; and main lifting lugs. The main frame includes upright posts, basal tubes, longitudinal tubes, transverse tubes, and diagonal tubes. The support frame includes cushion blocks, transverse beams, stand columns, carrier bars, and stiffeners. The ladder stands include stand pipes and a plurality of deformed bar. The main lifting lugs are disposed on the upright posts of the main frame. The support frame is in the form of a door frame and disposed in the lower part of the main frame. The carrier bars cross over the basal tubes. The stiffeners are disposed between the upright posts of the main frame and the transverse beams. The cushion blocks are disposed on the carrier bars. The movable base is disposed between the carrier bars of the support frame.

A transportation platform for an underwater towing device, including: a main frame; a support frame; a movable base; operation decks; ladder stands; and main lifting lugs. The main frame includes upright posts, basal tubes, longitudinal tubes, transverse tubes, and diagonal tubes. The support frame includes cushion blocks, transverse beams, stand columns, carrier bars, and stiffeners. The ladder stands include stand pipes and a plurality of deformed bar. The main lifting lugs are disposed on the upright posts of the main frame. The support frame is in the form of a door frame and disposed in the lower part of the main frame. The carrier bars cross over the basal tubes. The stiffeners are disposed between the upright posts of the main frame and the transverse beams. The cushion blocks are disposed on the carrier bars. The movable base is disposed between the carrier bars of the support frame.

A multi-cable subsea lifting system including two or more load-cable lifting apparatus (2a, 2b); a load cable (4a, 4b) extending from each load-cable lifting apparatus (2a, 2b) to a subsea attachment point; a torque measuring device (22) associated with each load cable (4a, 4b); one or more subsea anti-cabling devices (20), each anti-cabling device (20) including a motor (24) connected to a respective load cable (4a, 4b); and a controller (30) in communication with each motor (24) and torque measuring device (22); wherein the controller (30) is configured to actuate each motor (24) to impart a rotational force to its respective load cable (4a, 4b) in response to measurements obtained from the torque measuring device (22) with the aim to limit cabling, remove cabling or control heading either automatically or from external control.

A multi-cable subsea lifting system including two or more load-cable lifting apparatus (2a, 2b); a load cable (4a, 4b) extending from each load-cable lifting apparatus (2a, 2b) to a subsea attachment point; a torque measuring device (22) associated with each load cable (4a, 4b); one or more subsea anti-cabling devices (20), each anti-cabling device (20) including a motor (24) connected to a respective load cable (4a, 4b); and a controller (30) in communication with each motor (24) and torque measuring device (22); wherein the controller (30) is configured to actuate each motor (24) to impart a rotational force to its respective load cable (4a, 4b) in response to measurements obtained from the torque measuring device (22) with the aim to limit cabling, remove cabling or control heading either automatically or from external control.

The publication relates to a depth compensated actuator, for a transportable inline depth compensated heave com-pensator for subsea lifting operations. The actuator comprises a cylinder shaped body and a piston with a piston rod, the piston rod being intended for exposure to external water pressure, a first and second connection means associated with the actuator. Further, the actuator comprises a depth compensator comprising a cylinder, a piston and a piston rod, the end of which being exposed to surrounding water; and conduit means between at least one volume in the actuator and one volume in the depth compensator. The pistons and piston rods are shaped as any of: hollow piston rod, ring shaped piston, ring piston rod. The depth compensated actuator solves the problem if improving depth compensation performance regarding size, weight, required fluid consumption, internal/inherent friction and adaptability. Further, use of a depth compensated actuator is claimed.

A method and heave compensator for eliminating snap-load and heave effects at offshore deposition of a load into or onto the sea or seabed involves a heave compensator suspended between the load and the lifting device having a relatively stiff stroke response at small to moderate stroke lengths and then a softer stroke response at larger stroke lengths to avoid exceeding the dynamical amplification factor (DAF)-limitations of the crane/lifting device or on the load.

A method and heave compensator for eliminating snap-load and heave effects at offshore deposition of a load into or onto the sea or seabed involves a heave compensator suspended between the load and the lifting device having a relatively stiff stroke response at small to moderate stroke lengths and then a softer stroke response at larger stroke lengths to avoid exceeding the dynamical amplification factor (DAF)-limitations of the crane/lifting device or on the load.

The invention relates to a compensating device (200) for maintaining specifiable target positions of a load (206) which can be handled using a cable hoist (202) and which is attached to a cable (216) of the cable hoist, the respective specifiable target position of the load changing unintentionally to an actual position deviating from the target position. The compensating device consists of at least one sensor device (240, 242) for detecting the respective actual position of the load (206); a rotational drive (226, 228, 230) for specifying a cable length of the cable hoist (202); and at least one controller (244) which changes the cable length after the respective actual position has been detected until the load (206) re-assumes its target position. The respective drive (226, 228, 230) can be controlled at least partly by at least one hydraulic motor (226, 228, 230) with opposite rotational directions, said motor being connected to an actuating device (246) which has at least two separate pressure chambers (250, 252) with pressure levels that differ during operation, thereby forming a drive section (248) for the respective hydraulic motor (226, 228, 230), and which can be actuated by the controller (244).

The invention relates to a compensating device (200) for maintaining specifiable target positions of a load (206) which can be handled using a cable hoist (202) and which is attached to a cable (216) of the cable hoist, the respective specifiable target position of the load changing unintentionally to an actual position deviating from the target position. The compensating device consists of at least one sensor device (240, 242) for detecting the respective actual position of the load (206); a rotational drive (226, 228, 230) for specifying a cable length of the cable hoist (202); and at least one controller (244) which changes the cable length after the respective actual position has been detected until the load (206) re-assumes its target position. The respective drive (226, 228, 230) can be controlled at least partly by at least one hydraulic motor (226, 228, 230) with opposite rotational directions, said motor being connected to an actuating device (246) which has at least two separate pressure chambers (250, 252) with pressure levels that differ during operation, thereby forming a drive section (248) for the respective hydraulic motor (226, 228, 230), and which can be actuated by the controller (244).

The present embodiments relate to launch and recovery systems for a remotely operated vehicle. The embodiments eliminate or minimize the need for load lines, and provide virtually unlimited excursion distances for remotely operated vehicles, limited only by the amount of tether available at the launch point. Further, the embodiments allow for extended deployments of ROVs by allowing recharging of a tether climbing component while submerged. The system can include a launch and recovery assembly, a tether climbing component, and a remotely operated vehicle attached to a remotely operated vehicle tether. The launch and recovery assembly deploys the remotely operated vehicle and the tether climbing component overboard, and the remotely operated vehicle is configured for tethered operation while maintaining the tether climbing component at a desired depth.