Provided is an electric winch apparatus capable of preventing irregular winding of a wire rope caused by landing of a hoisted-down suspended load. The electric winch apparatus includes a winch drum (5) around which a wire rope (2) is wound, an electric motor (8) which rotates the winch drum (5), an operation lever (13a), a measurement unit (18) which measures a tension index value corresponding to a tension in the wire rope (2), and a controller (12) which controls motion of the electric motor (8). The controller (12) stops motion of the electric motor (8) when an operation in a lowering operation direction is applied the operation lever (13a) and a tension average value as an average value of a tension in the wire rope (2) becomes less than or equal to a predetermined tension reference value, the average value of the tension corresponding to an average value of the tension index value in a predetermined period.

A method of spooling a crane rope (2) onto a crane drum through a crane rope spooling system (1) from a reel (31) under a predetermined back tension is described and includes the steps of: unspooling the crane rope (2) from a reel (31) and passing the crane rope through a tensioning system (10) comprising a primary back tensioner (12) and a secondary back tensioner (16); gripping the crane rope (2) within the secondary back tensioner (16) and thereby preloading the crane rope (2) with tension prior to the crane rope (2) passing through the primary back tensioner (12); and applying a predetermined back tension to the crane rope (2) with the primary back tensioner (12) as the crane rope (2) is being spooled onto the crane drum under the predetermined back tension.

A crane rope spooling system (1) for spooling crane rope (2) onto a crane drum under a predetermined back tension is also described, said system (10) comprising a tensioning system (10) comprising at least a primary back tensioner (12) and a secondary back tensioner (16) and a reel (31).

A method can include receiving information associated with a conveyance of equipment in a borehole via a cable; determining cable tension values based at least in part on a model and at least a portion of the information; conveying the equipment in the borehole via the cable; acquiring a cable tension value via one or more sensors; comparing the acquired cable tension value to at least one of the determined cable tension values; and, based at least in part on the comparing, setting a cable tension limit for further conveying of the equipment in the borehole via the cable

A method for securing a lifting movement of a load mechanically coupled to a hook of a lifting device by flexible links, wherein the flexible links can be, when the load is placed on the ground, either in a stretched state or in a relaxed state. The method includes detecting an initiation of a transitional phase between an initial instant when the load is placed on the ground and a final instant when the load is suspended in the air; and emitting a detection signal of a proscribed lifting situation, if the flexible links are, at least at an instant of the transitional phase, in the relaxed state.

A method and a system for controlling the winding/unwinding of a rope portion onto/from a rotary drum, comprises the step of making available a rope which is at least partially wound onto a rotary drum, wherein the rope is guided from the rotary drum along a defined path as far as a hauling point, wherein a traction force acts on the rope beyond the hauling point. The method comprises unwinding or winding the rope by executing a rotation of the rotary drum, such that a defined rope portion is moved along the defined path; and determining the length of the defined rope portion in the region of the defined path. The method comprises determining an angle difference corresponding to the rotation of the rotary drum; and controlling the rotary drum for further winding/unwinding taking into account the length and the angle difference. A calibration in the region of the defined path during the use of the rotary drum provides a control for the rotary drum.

A self-homing hoist includes a controller configured to initiate a self-homing process to return the hook assembly to a homed position in response to each of at least one homing factor being true. Each homing factor is true or false based on a comparison of the current condition of the homing factor with a threshold requirement. If the current condition satisfies the threshold requirement, then the homing factor is true. If the current condition does not satisfy the threshold requirement, then the homing factor is false. Where all homing factors are true, the controller can initiate the self-homing process by activating a hoist motor to drive the cable drum and reel the hook assembly into the homed position.

A method for wireline intervention in a subsea well from a floating vessel.

A load-relieving apparatus includes a wire cable 36 with a free end and a fixed end opposite to the free end, a locking part 361 being attached to the free end, a winding part 334 configured to wind the wire cable 36 from a fixed-end side thereof, a pulley 335 interposed between the winding part 334 and the locking part 361, and configured to stretch the wire cable therebetween, and a cover 336 with a through hole 338H formed therein through which the wire cable 36 is inserted, the cover 336 being interposed between the locking part 361 and the pulley 335, and formed so as to cover at least a part of the pulley 335. Further, the through hole 338H is configured so that a relative position of the through hole 338H with respect to a rotation axis of the pulley 335 changes.

A winch controller for a hoisting apparatus for a wireline operation operates as a closed loop controller. The winch controller is adapted to control a winch or, if included, a winch and a capstan in a coordinated manner. The winch controller may utilize process variables including the tension of the cable between the winch and the capstan. The controller is coupled to a power pack adapted to power the winch and capstan. The power pack and controller are configured such that the capstan may be selectively removed from the system when it is not needed.

A self-homing hoist includes a controller configured to initiate a self-homing process to return the hook assembly to a homed position in response to each of at least one homing factor being true. Each homing factor is true or false based on a comparison of the current condition of the homing factor with a threshold requirement. If the current condition satisfies the threshold requirement, then the homing factor is true. If the current condition does not satisfy the threshold requirement, then the homing factor is false. Where all homing factors are true, the controller can initiate the self-homing process by activating a hoist motor to drive the cable drum and reel the hook assembly into the homed position.