A method for securing an angular position of a crane jib displaceable in lifting and in lowering by a winch integrating a motor driving a drum on which is wound a rope and secured to a platen provided with arcuate oblong locking holes, the method including measuring a speed parameter representative of an angular speed of the jib, controlling the motor to displace the jib with a limitation of the speed parameter to a first maximum value and a limitation of a motor torque to a first limit value, until reaching an angular position in which a lock is aligned with and locked into the locking hole, and controlling the motor to displace the jib in lowering with a limitation of the speed parameter to a second maximum value and a limitation of the motor torque to a second limit value, until the speed parameter is null for a predetermined time period to stop the motor.

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.

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.

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 curved extension guide connected to the jib.

A vehicle crane having a luffable main jib and an additional jib system arranged on a free end section of the main jib and comprising a first additional jib part and a second additional jib part. To further reduce the weight of the additional jib system and the vehicle crane fitted therewith, and to permit an overall more economical mode of production, the first additional jib part has a rectangular cross-section having four longitudinal chords connected together via transverse struts or/and diagonal struts and the second additional jib part has a triangular cross-section having three longitudinal chords connected together via transverse struts, wherein the two additional jib parts are coupled, or can be coupled, together via a cross-section change adapter.

The invention relates to a method and to a device for implementing the method for tensioning an inextensible or substantially inextensible longitudinal strap (12) comprising a distal end portion (15) and a proximal end portion (11), each end portion being respectively fixed to a corresponding attachment point (13, 16). The method is characterized in that a cycle (2) of successive transverse pressure applications is exerted on the strap (12), comprising a first transverse pressure application (23) on a first portion (20) of die strap then a second (24) and a third (25) transverse pressure application on a second (21) and a third (22) portion of the strap, respectively.

The invention relates to a method and to a device for implementing the method for tensioning an inextensible or substantially inextensible longitudinal strap (12) comprising a distal end portion (15) and a proximal end portion (11), each end portion being respectively fixed to a corresponding attachment point (13, 16). The method is characterized in that a cycle (2) of successive transverse pressure applications is exerted on the strap (12), comprising a first transverse pressure application (23) on a first portion (20) of die strap then a second (24) and a third (25) transverse pressure application on a second (21) and a third (22) portion of the strap, respectively.

Disclosed is a knuckle boom crane, for offshore application, the knuckle boom crane including a crane house, a knuckle boom carried by the crane house, a component for operating the crane house and the knuckle boom, and a controller for piloting the operating component. The controller include a active compensation module that is designed to pilot the operating means, taking into account data coming from a motion reference unit, in such a way as to stabilize a downstream end of the jib, advantageously in a horizontal plane and/or a vertical position, still preferably in all directions.

A crane, in particular a mobile crane, includes a crane jib which can be moved about a substantially horizontal luffing axis, and a tensioning device for the crane jib. The tensioning device includes two pendants which run from the jib tip to the jib base of the crane jib and tensioning posts each tensioning a respective one of the pendants relative to the crane jib in a triangular configuration. In order to operate the crane, a luffing angle of the crane jib about the luffing axis is measured or recorded, and a spread angle between the tensioning posts while the crane jib is being used is modified depending on the luffing angle.

A system for lifting heavy loads, that includes an apparatus having at least one mast or part of such mast, from which a load may be suspended and a removable erection facility external of the apparatus and disposed on a base on the ground, which erection facility includes an assembly frame having a push-up and lowering capability for the at least one mast or part of such mast, which erection facility is equipped to receive during erection of the apparatus or to remove during dismantling of the apparatus, a mast piece or a series of mast pieces below an assembly of mast pieces above said mast piece or series of mast pieces for converting the apparatus between a dismantled position and a fully erected position, at least that portion of the erection facility having the push-up and lowering capability being removable away from the apparatus and base after erection of the apparatus.