An adjustable length tensioning member that comprises a rope, a first connector on the rope, a second connector on the rope, and a plurality of connection points between the first connector and the second connector is disclosed. The plurality of connection points have a diameter greater than a diameter of the rope. The rope may be passed through a socket coupled to a first crane component and one of the connectors on the rope is coupled to a second crane component. One of the plurality of connection points engages a seat on the socket to tension the rope between the socket and the connection point.

A back stop for a crane which eliminates operator's discomfort and adverse effects on surrounding environment due to generation of abnormal noise and enables greasing work to be facilitated. A back stop includes an outer casing having a base end portion turnably connected to a boom or a crane main body and an opening portion opened in the outer casing front end portion; an inner casing having a base end portion turnably connected to the crane main body or the boom and having a front end portion side slidably fitted into the outer case through the opening portion; and a greasing tube arranged in the outer casing or the inner casing. An inlet of the greasing tube is arranged outside of the outer casing or outside of the inner casing on the base end portion side on which the greasing tube is arranged. A discharge port of the greasing tube is attached to a front end portion of the inner casing.

A mobile crane is configured so that a boom is raised by a derrick cylinder in response to a raise signal output from a derrick lever and the derrick cylinder is stopped in response to the derrick angle of the boom reaching the maximum angle corresponding to the hoisted-down length of a rope.

A working machine, in particular a material handling machine, has a boom and a boom bracing actuated by an actuator operatively connected to the boom bracing by a lever rotatably articulated to a turntable, to introduce the required tensile force into the bracing.

A dual hoist crane is provided with a heave compensation system that can be used for both the main and for the auxiliary hoisting assembly. The heave compensation system includes a first set of sheaves for guiding the main hoisting cable and a second set of sheaves for guiding the auxiliary hoisting cable. The heave compensation system is configured to individually lock the first set of sheaves and the second set of sheaves to a heave compensation cylinder, for respectively providing the main hoisting assembly and the auxiliary hoisting assembly with heave compensation.

The disclosure relates to a crane, in particular a mobile lattice boom crane, having an upper carriage, a tiltable boom articulated to the upper carriage and a tiltable bracing frame articulated to the upper carriage. The bracing frame can be connected to the boom via a bracing and is connected to the upper carriage via an actively adjustable bracing cable, wherein the bracing cabling comprises a bracing cable mounted on a cable winch so that it can be wound up and unwound. According to the disclosure, the crane comprises a variable-length traction element, via which the bracing frame can be connected to the boom in an articulated manner and which is designed to exert a tractive force on the bracing frame in the direction of the boom. The disclosure also relates to a method for moving a crane according to the disclosure into a braced operating position.

A dual hoist crane is provided with a heave compensation system that can be used for both the main and for the auxiliary hoisting assembly. The heave compensation system includes a first set of sheaves for guiding the main hoisting cable and a second set of sheaves for guiding the auxiliary hoisting cable. The heave compensation system is configured to individually lock the first set of sheaves and the second set of sheaves to a heave compensation cylinder, for respectively providing the main hoisting assembly and the auxiliary hoisting assembly with heave compensation.

A crane includes: a boom; a jib; a front post that is swingably attached to a tip end side of the boom; a rear post that is swingably attached to the tip end side of the boom; a post-side pendant member, with one end of the post-side pendant member being attached to a tip end of the rear post; a boom-side pendant member, with one end of the boom-side pendant member being attached to another end of the post-side pendant member, and another end of the boom-side pendant member being attached to the boom; and a post driving device having a link mechanism that rotates the rear post in a range including a position at which the rear post is swung down to the front post side and a position at which the rear post is swung down to the boom side, while the boom is held down in a horizontal position.

The disclosure relates to a crane and a method for luffing the boom of a crane, in particular a mobile lattice boom crane, having an upper carriage and a boom articulated to the upper carriage so as to pivot about a horizontal axis. The boom is braced via a bracing frame mounted on the upper carriage and can be luffed up and down by pivoting the bracing frame. The crane comprises a luffing aid device, which can exert a torque acting in addition to the bracing on the boom for luffing the boom in a flat boom position. The luffing aid device comprises an auxiliary arm pivotably mounted on the upper carriage and connected to the upper carriage via a retaining element and to the boom via a variable-length traction element. The traction element exerts a tractive force on the boom in the direction of the auxiliary arm.

The present disclosure discloses an operating method of a wind power jib of a crane and a crane, and relates to the field of engineering machinery. The method includes the following steps: rotatably connecting a main boom and a wind power jib; overturning the wind power jib to a first preset position by using a traction means of the crane; contacting a cushioning member with the wind power jib provided at the first preset position; further drawing the wind power jib to overturn to a second preset position; releasing the traction means, such that the wind power jib overturns automatically under the effect of self gravity and a cushioning member until the wind power jib is overturned in position.