The invention relates to a work machine, comprising a mast having a mast head, a support cable which is guided along the mast, over the mast head, a cable winch comprising a rotatably mounted winding drum to which the support cable is attached for winding up and unwinding, a work element which is arranged on the support cable for vertical movement, and a control unit, by means of which the cable winch can be operated in an unwinding mode, for unwinding the support cable from the winding drum, in which mode the work element is lowered, on the support cable, as far as a base surface. According to the invention, a cable contact pressure means comprising at least one contact pressure element is provided, which element can be adjusted into a contact pressure position by the control unit, by means of an actuating member, in order to counteract a cable oscillation of the support cable when the base surface is struck, in which contact pressure position the contact pressure element rests on the support cable at a contact pressure force.

The invention relates to a work machine, comprising a mast having a mast head, a support cable which is guided along the mast, over the mast head, a cable winch comprising a rotatably mounted winding drum to which the support cable is attached for winding up and unwinding, a work element which is arranged on the support cable for vertical movement, and a control unit, by means of which the cable winch can be operated in an unwinding mode, for unwinding the support cable from the winding drum, in which mode the work element is lowered, on the support cable, as far as a base surface. According to the invention, a cable contact pressure means comprising at least one contact pressure element is provided, which element can be adjusted into a contact pressure position by the control unit, by means of an actuating member, in order to counteract a cable oscillation of the support cable when the base surface is struck, in which contact pressure position the contact pressure element rests on the support cable at a contact pressure force.

A compensated elevator link is disclosed. In at least one aspect, the compensated elevator link comprises a plurality of cylinder housings and a rod having a plurality of ends, each end comprising a piston head adapted to be slideably received within one of the cylinder housings for defining first and second hydraulic cylinders. Each hydraulic cylinder has at least one annulus for receiving a non-compressible fluid. The rod comprises a passage for receiving a compressible fluid, wherein each piston head comprises at least one passage to allow selective displacement of the non-compressible fluid between the annulus of the cylinder housing and the passage within the rod during selective displacement of the hydraulic cylinders between a contracted condition to an extended condition for either compression or expansion of the compressible fluid by the non-compressible fluid.

A compensated elevator link is disclosed. In at least one aspect, the compensated elevator link comprises a plurality of cylinder housings and a rod having a plurality of ends, each end comprising a piston head adapted to be slideably received within one of the cylinder housings for defining first and second hydraulic cylinders. Each hydraulic cylinder has at least one annulus for receiving a non-compressible fluid. The rod comprises a passage for receiving a compressible fluid, wherein each piston head comprises at least one passage to allow selective displacement of the non-compressible fluid between the annulus of the cylinder housing and the passage within the rod during selective displacement of the hydraulic cylinders between a contracted condition to an extended condition for either compression or expansion of the compressible fluid by the non-compressible fluid.

An affordable tension device for maintaining tension on a wire rope of a cable-based lifting system is provided. The tension device has an elongated casting weight adapted to govern the casting weight as it rides along a predetermined wire rope for maintaining tension thereon. The tension device provides a clevis with a sheave for operatively associating with the tension wire rope.

An affordable tension device for maintaining tension on a wire rope of a cable-based lifting system is provided. The tension device has an elongated casting weight adapted to govern the casting weight as it rides along a predetermined wire rope for maintaining tension thereon. The tension device provides a clevis with a sheave for operatively associating with the tension wire rope.

A control method controls a movable member of an excavator including a movable member holding a load, an actuator with electric motor and static brake, a control unit and a motion sensor unit. The static brake and electric motor generate respectively an upper threshold brake force and an upper threshold motor force. An immobilization operation provides that the static brake generates the upper threshold brake force and the electric motor is stopped. A slippage detection operation provides that the control unit detects whether an electric actuator is moving despite the static brake. If the electric actuator is moving, a motor energizing operation provides that the electric motor generates a motor force equal or superior to upper threshold brake force in a direction opposite to the slippage direction. After energizing the motor, a brake release operation provides that the control unit releases the static brake.

A deepwater hoisting system includes a synthetic fibre rope winch assembly including a motor driven first winch and a length of synthetic fibre rope driven by said first winch. The synthetic fibre rope has an end remote from the first winch. The system further includes a steel wire winch assembly including a motor driven second winch and a length of steel wire driven by said second winch. The steel wire has an end remote from the second winch. At least the second winch is an active heave compensation motor driven winch. The system further includes a lifting block having a lifting block sheave, through which the synthetic fibre rope is run. The end of the synthetic fibre rope is connected to the end of the steel wire, so that the lifting block is suspended in a double-fall arrangement.

A deepwater hoisting system includes a synthetic fibre rope winch assembly including a motor driven first winch and a length of synthetic fibre rope driven by said first winch. The synthetic fibre rope has an end remote from the first winch. The system further includes a steel wire winch assembly including a motor driven second winch and a length of steel wire driven by said second winch. The steel wire has an end remote from the second winch. At least the second winch is an active heave compensation motor driven winch. The system further includes a lifting block having a lifting block sheave, through which the synthetic fibre rope is run. The end of the synthetic fibre rope is connected to the end of the steel wire, so that the lifting block is suspended in a double-fall arrangement.

An STS crane (Ship-to Shore) includes a portal frame structure; a boom which has a portion extending on a ship's side as well as a portion extending on a quay side; a trolley moving along the boom; a hoisting mechanism which has a rope drum for hoisting ropes, whereby the hoisting ropes are routed from the rope drum through boom ends to the trolley; auxiliary trolleys which move along the boom on both sides of the trolley to support and/or tighten the hoisting ropes; and a folding joint on the boom portion extending on the ship's side for folding up the folding portion of the boom extending to the direction of the ship from the folding joint; whereby there are auxiliary trolley rails arranged for the auxiliary trolleys, these auxiliary trolley rails being separate from the trolley rails; and whereby the drive roping of the auxiliary trolleys is divided into two separate and independent drive ropings which have separate and independent drive mechanisms and which are on different sides of the folding joint on the boom.