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.

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 invention relates to a telescopic boom comprising a coupling section, on the side of which at least two luffing-cylinder mounts are provided for fastening luffing cylinders to the telescopic boom. The bearing plates of the luffing-cylinder mount transition into a metal-plate box structure, the metal-plate box structure being composed of three partial luffing-cylinder boxes.

The invention relates to a telescopic boom comprising a coupling section, on the side of which at least two luffing-cylinder mounts are provided for fastening luffing cylinders to the telescopic boom. The bearing plates of the luffing-cylinder mount transition into a metal-plate box structure, the metal-plate box structure being composed of three partial luffing-cylinder boxes.

The focus of the present disclosure is on portable cranes and cantilevered base systems. In particular, portable cranes and cantilevered base systems which are lightweight, easy-to-operate, safe, inexpensive, and have extended reaches with high-load capacities would be advantageous for a variety of applications. A cantilevered support to a pivotable arm that is provided by the present disclosure provides advantages when compared to other portable cranes, such as the ability to: 1) extend an arm and reach of a crane, 2) increase a load that can be lifted or lowered, 3) operate a portable crane and cantilevered base system freestanding without attaching a base to a floor, surface, or bed of a vehicle, and 4) augment the structural capacity of a portable crane and cantilevered base with mechanical devices to support a variety of applications.

The focus of the present disclosure is on portable cranes and cantilevered base systems. In particular, portable cranes and cantilevered base systems which are lightweight, easy-to-operate, safe, inexpensive, and have extended reaches with high-load capacities would be advantageous for a variety of applications. A cantilevered support to a pivotable arm that is provided by the present disclosure provides advantages when compared to other portable cranes, such as the ability to: 1) extend an arm and reach of a crane, 2) increase a load that can be lifted or lowered, 3) operate a portable crane and cantilevered base system freestanding without attaching a base to a floor, surface, or bed of a vehicle, and 4) augment the structural capacity of a portable crane and cantilevered base with mechanical devices to support a variety of applications.

An intermediate support holder includes right and left guy line retaining units, right and left intermediate support line retaining units, and a connecting unit. The intermediate portions of the guy lines can be attached to the guy line retaining units. The intermediate support line retaining units are disposed so as to be aligned in the right-left direction with respect to the guy line retaining units, and base end portions of the intermediate support lines can be attached to the intermediate support line retaining units. The connecting unit couples and fixes the pair of right and left guy line retaining units and the pair of right and left intermediate support line retaining units to each other.

An intermediate support holder includes right and left guy line retaining units, right and left intermediate support line retaining units, and a connecting unit. The intermediate portions of the guy lines can be attached to the guy line retaining units. The intermediate support line retaining units are disposed so as to be aligned in the right-left direction with respect to the guy line retaining units, and base end portions of the intermediate support lines can be attached to the intermediate support line retaining units. The connecting unit couples and fixes the pair of right and left guy line retaining units and the pair of right and left intermediate support line retaining units to each other.

The invention relates to a mobile crane having a telescopic boom that is luffably coupled to a superstructure and that comprises a coupling section and at least one telescopic section supported therein in a retractable and extendable manner. At least one guying support is fastened to the coupling section and is connected to the coupling section or to the superstructure via a first guying and to a connection piece at a telescopic section via a second guying. In accordance with the invention, the second guying comprises at least two guying elements coupled with one another. The second guying is thereby adjustable in length and is thus adaptable to the extension length of the telescopic boom such that at least one of the mutually coupled guying elements is directly releasably connectable to the guying support. The invention further relates to a guying system for a mobile crane in accordance with the invention, to a method of moving a mobile crane in accordance with the invention into a guyed work position, and to a method of varying the extension length of the guyed telescopic boom of a mobile crane in accordance with the invention.

The disclosure relates to a mobile crane, such as a crawler crane, comprising an undercarriage having a traveling gear, a superstructure rotatably supported about a vertical axle on the undercarriage, a boom connected in an articulated manner to the superstructure pivotable about a horizontal axle, an A frame connected to the boom via a guying means, and a retraction mechanism by means of which the A frame is pivotable. In accordance with the disclosure, the A frame is separable and comprises a pole connected in an articulated manner to the superstructure and a folding pole releasably connected to the pole.