A system for bridle bite adjustment can include a tow rope coupled to a paravane at a first position on a lever arm and a spur line coupled to the paravane at a second position on the lever arm. The system can also include a winch to adjust a deployed length of the tow rope. The tow rope and the lever arm can adjust a bridle bite of the paravane by when the deployed length of the tow rope is adjusted by the winch, thereby balancing tension between the tow rope and the spur line.

A compensating device (200) maintains specifiable target positions of a load (206) handled using a cable hoist (202) and attached to a cable (216) of the cable hoist. The respective specifiable target position of the load may change unintentionally to an actual position deviating from the target position. The compensating device has a sensor device (240, 242) for detecting the respective actual position of the load (206). A rotational drive (226, 228, 230) specifies a cable length of the cable hoist (202). A controller (244) 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 a hydraulic motor (226, 228, 230) with opposite rotational directions. The motor is connected to an actuating device (246) having 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).

A compensating device (200) maintains specifiable target positions of a load (206) handled using a cable hoist (202) and attached to a cable (216) of the cable hoist. The respective specifiable target position of the load may change unintentionally to an actual position deviating from the target position. The compensating device has a sensor device (240, 242) for detecting the respective actual position of the load (206). A rotational drive (226, 228, 230) specifies a cable length of the cable hoist (202). A controller (244) 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 a hydraulic motor (226, 228, 230) with opposite rotational directions. The motor is connected to an actuating device (246) having 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).

A lightweight winch has the motor assembly centered with a housing within the winch drum where it may be easily accessed and removed from the winch drum. The winch comprises an improved, non-load bearing level wind mechanism for evenly winding cable about the winch drum. And a small-footprint level wind system having elongate support, a leadscrew, a guide substantially supported by the support, the guide adapted to accept a tension member. The guide designed to move along the support and to transfer tension member forces onto the support. Further comprising a motor, adapted to apply a motive onto the leadscrew, a shuttle connected the guide and leadscrew and adapted to transfer the motive force to the guide, moving the guide along the support. Also provides direct tension member metering and load sensing within the guide, and a load-bearing leadscrew having a direct connection between guide and leadscrew.

A lightweight winch has the motor assembly centered with a housing within the winch drum where it may be easily accessed and removed from the winch drum. The winch comprises an improved, non-load bearing level wind mechanism for evenly winding cable about the winch drum. And a small-footprint level wind system having elongate support, a leadscrew, a guide substantially supported by the support, the guide adapted to accept a tension member. The guide designed to move along the support and to transfer tension member forces onto the support. Further comprising a motor, adapted to apply a motive onto the leadscrew, a shuttle connected the guide and leadscrew and adapted to transfer the motive force to the guide, moving the guide along the support. Also provides direct tension member metering and load sensing within the guide, and a load-bearing leadscrew having a direct connection between guide and leadscrew.

A method of providing motion compensation of a subsea package with a synthetic rope comprising attaching the synthetic rope to the subsea package, supporting a first gripper with a wire rope from a winch capable of motion compensation control characteristics and gripping the synthetic rope with the first gripper, supporting a second gripper with a second wire rope, and repeating the following sequence: lowering the first gripper, the synthetic rope, and the subsea package a first distance, gripping the synthetic rope with the second gripper, releasing the first gripper from the synthetic rope, raising the first gripper the first distance, gripping the synthetic rope with the first gripper, releasing the second gripper from the synthetic rope, such that when the subsea package is lowered proximate the subsea landing location the winch capable of operating with motion compensation characteristics can operate to compensate for the vessel motion and smoothly lower the subsea package to the subsea landing location.

A method of providing motion compensation of a subsea package with a synthetic rope comprising attaching the synthetic rope to the subsea package, supporting a first gripper with a wire rope from a winch capable of motion compensation control characteristics and gripping the synthetic rope with the first gripper, supporting a second gripper with a second wire rope, and repeating the following sequence: lowering the first gripper, the synthetic rope, and the subsea package a first distance, gripping the synthetic rope with the second gripper, releasing the first gripper from the synthetic rope, raising the first gripper the first distance, gripping the synthetic rope with the first gripper, releasing the second gripper from the synthetic rope, such that when the subsea package is lowered proximate the subsea landing location the winch capable of operating with motion compensation characteristics can operate to compensate for the vessel motion and smoothly lower the subsea package to the subsea landing location.

A wave-induced motion compensation crane and corresponding vessel and method are disclosed. The crane includes a motion compensation device at a tip end portion of the boom structure to compensate for X-Y wave-induced motion and a heave compensation device for Z-motion. The motion compensation device includes a moveable jib beam that extends in a substantially horizontal direction. The jib beam is slewable about a substantially vertical slew axis and translatable in a longitudinal direction of the jib beam. Preferably, the jib beam can be levelled based on the angular orientation of the boom structure.

A tension balance system for steel wire ropes on a friction hoisting driving end of an ultra-deep well includes a friction wheel, left and right guiding wheels, left and right steel wire ropes, left and right adjustment wheels, left and right rewinding wheels, left and right adjustment oil cylinders, a hydraulic pipeline, a pump station, a pipeline switch group, left and right hoisting containers, balance ropes, and reels. The friction wheel is disposed in the middle, the left and right adjustment wheels and the left and right rewinding wheels are circularly distributed around the friction wheel, the left and right guiding wheels, the left and right adjustment wheels, and left and right rewinding wheels are all symmetrically disposed on two sides of the friction wheel; both a quantity of left steel wire ropes and a quantity of right steel wire ropes are even numbers more than 2.

A tension balance system for steel wire ropes on a friction hoisting driving end of an ultra-deep well includes a friction wheel, left and right guiding wheels, left and right steel wire ropes, left and right adjustment wheels, left and right rewinding wheels, left and right adjustment oil cylinders, a hydraulic pipeline, a pump station, a pipeline switch group, left and right hoisting containers, balance ropes, and reels. The friction wheel is disposed in the middle, the left and right adjustment wheels and the left and right rewinding wheels are circularly distributed around the friction wheel, the left and right guiding wheels, the left and right adjustment wheels, and left and right rewinding wheels are all symmetrically disposed on two sides of the friction wheel; both a quantity of left steel wire ropes and a quantity of right steel wire ropes are even numbers more than 2.