In a working machine, a plurality of diagonal members includes a plurality of first diagonal members for connecting a first main member and a second main member with each other, the first diagonal members including a first nearest diagonal member located nearest to a first connector connected to an end of the first main member. A first reinforcement part extends from the first nearest diagonal member to the second main member or a second connector in a first specific direction for connecting the first nearest diagonal member and, the second main member or the second connector connected to an end of the second main member with each other.

In a working machine, a plurality of diagonal members includes a plurality of first diagonal members for connecting a first main member and a second main member with each other, the first diagonal members including a first nearest diagonal member located nearest to a first connector connected to an end of the first main member. A first reinforcement part extends from the first nearest diagonal member to the second main member or a second connector in a first specific direction for connecting the first nearest diagonal member and, the second main member or the second connector connected to an end of the second main member with each other.

A pivot-forming crane element for a rotating portion of an element-mounted crane includes a framework on which a motor-driven orienting system, a hoisting winch and a dispensing winch are mounted. The motor-driven orienting system includes a pivot mechanism about an orienting axis and at least one orienting electric motor cooperating with the pivot mechanism to make the framework pivot about the orienting axis. The hoisting winch is provided with a hoisting electric motor cooperating with a hoisting drum around which a hoisting rope is wound. The dispensing winch is provided with a dispensing electric motor cooperating with a dispensing drum around which a dispensing rope is wound.

A pivot-forming crane element for a rotating portion of an element-mounted crane includes a framework on which a motor-driven orienting system, a hoisting winch and a dispensing winch are mounted. The motor-driven orienting system includes a pivot mechanism about an orienting axis and at least one orienting electric motor cooperating with the pivot mechanism to make the framework pivot about the orienting axis. The hoisting winch is provided with a hoisting electric motor cooperating with a hoisting drum around which a hoisting rope is wound. The dispensing winch is provided with a dispensing electric motor cooperating with a dispensing drum around which a dispensing rope is wound.

A marine knuckle boom crane includes a crane housing which is rotational relative to a pedestal about a vertical rotation axis and a knuckle boom assembly attached to the crane housing. The knuckle boom assembly includes a main boom, the inner end of which is connected pivotably about a first horizontal pivot axis to the crane housing; and a jib, the inner end of which is connected pivotably about a second horizontal pivot axis to the outer end of the main boom, wherein the jib is pivotable at least between an extended position in which the tip extends mainly forward from the main boom, and a folded position in which the jib is folded back, essentially parallel along the main boom. In order to position the jib with respect to the main boom, a tensioning member is provided extending between the crane housing and a guide structure connected to the jib.

A marine knuckle boom crane includes a crane housing which is rotational relative to a pedestal about a vertical rotation axis and a knuckle boom assembly attached to the crane housing. The knuckle boom assembly includes a main boom, the inner end of which is connected pivotably about a first horizontal pivot axis to the crane housing; and a jib, the inner end of which is connected pivotably about a second horizontal pivot axis to the outer end of the main boom, wherein the jib is pivotable at least between an extended position in which the tip extends mainly forward from the main boom, and a folded position in which the jib is folded back, essentially parallel along the main boom. In order to position the jib with respect to the main boom, a tensioning member is provided extending between the crane housing and a guide structure connected to the jib.

A boom assembly according to the disclosure may include a lower boom structure, and an upper boom structure that is connected to the lower boom structure. In addition, the boom assembly may include a counterweight movably mounted on one of the boom structures and movable along the one boom structure when at least a portion of the lower boom structure is moved relative to the upper boom structure or when at least a portion of the upper boom structure is moved relative to the lower boom structure.

A lifting device includes a drive, a speed change gear device arranged above the drive and configured to be rotatable by means of the drive, a transmission device connected to the speed change gear device and a lifting mechanism fixed in the transmission device, and the speed change gear device is fixed to a side wall of the transmission device. Under an action of the drive and a speed change of speed change gear device, a gravity of a weight suspended on the lifting device is converted, so that the weight is lifted under a small force. The lifting device can also be driven via an electric hand tool. In addition, a first transmission device and a second transmission device are provided with a safety device to lock the lifting device when reaching a top, so as to prevent the lifting device from slipping to cause injuries.

A hoisting crane for use on an offshore vessel, such a vessel and a method for hoisting an offshore wind turbine component wherein use is made of such a crane and/or vessel. The hoisting crane includes a base structure, a superstructure, a boom having a longitudinal axis and a length of 80-200 meters. The boom includes a proximal portion connected to the boom connection member, formed integral via a joint structure with a single distal leg, wherein the length of the distal leg between the joint and the boom head structure exceeds 30 meters.

A hoisting crane for use on an offshore vessel, such a vessel and a method for hoisting an offshore wind turbine component wherein use is made of such a crane and/or vessel. The hoisting crane includes a base structure, a superstructure, a boom having a longitudinal axis and a length of 80-200 meters. The boom includes a proximal portion connected to the boom connection member, formed integral via a joint structure with a single distal leg, wherein the length of the distal leg between the joint and the boom head structure exceeds 30 meters.