Abstract: A counterweight loading and unloading device and a movable crane have a freestanding pallet (10) with two ends whose upper end faces are used for holding a counterweight (61). The two ends of the freestanding pallet (10) are both equipped with a cavity, and at least one telescopic oil cylinder (11, 12, 13, and 14) is provided in the cavity. A fixed end of the telescopic oil cylinder is fixed with the freestanding pallet (10), and a telescopic end of the telescopic oil cylinder is coupled with a pallet lifting mechanism for lifting the freestanding pallet. The device is not limited by a planar space of a vehicle frame and a turntable height of the movable crane. An integral dimension of the movable crane is not increased, thus preventing integral dimension of the movable crane from exceeding a road traveling standard. The structure of the device is more compact, and the telescopic oil cylinder plays a role of the counterweight, thus enabling stress of the turntable to be more reasonable.

Abstract: A crane transition assisting device, a transport trailer with the assisting device and a crane disassembling/assembling method by use of the assisting device are disclosed. The crane transition assisting device comprises a bearing frame (130) and supporting legs (110) which are mounted on the bearing frame and are equipped with a hydraulic cylinder (111) telescoping in a vertical direction. The bearing frame (130) is provided with at least two suspension arm brackets (120) arranged along the longitudinal direction of a horizontal plane and used for supporting a suspension arm. The assisting device realizes separation or combination of the suspension arm and a rotary table without an assistant lifting mechanism while disassembling/assembling a large-tonnage wheel crane so as to conveniently realize disassembling/assembling a large-tonnage wheel crane.

Abstract: A control system for a super-lifting device of a crane comprises a pressure-detecting element (21) for detecting the pressure of a variable amplitude oil cylinder and obtaining a measured pressure value, and a control element (22) for comparing the measured pressure value with the predetermined pressure value. When the measured pressure value is larger than or equal to the predetermined pressure value, the tensioning oil cylinder (23) is shortened, therefore increasing the tensioning pressure of the tensioning oil cylinder (23), reinforcing the tension of the super-lifting cable wire in the super-lifting device, and increasing the super-lifting moment applied to the main arm by the super-lifting device, which can effectively balance the pressure of the variable amplitude oil cylinder. A control method and a super-lifting device with the above control system are disclosed.

Abstract: A counterweight loading and unloading device and a movable crane have a freestanding pallet (10) with two ends whose upper end faces are used for holding a counterweight (61). The two ends of the freestanding pallet (10) are both equipped with a cavity, and at least one telescopic oil cylinder (11, 12, 13, and 14) is provided in the cavity. A fixed end of the telescopic oil cylinder is fixed with the freestanding pallet (10), and a telescopic end of the telescopic oil cylinder is coupled with a pallet lifting mechanism for lifting the freestanding pallet. The device is not limited by a planar space of a vehicle frame and a turntable height of the movable crane. An integral dimension of the movable crane is not increased, thus preventing integral dimension of the movable crane from exceeding a road traveling standard. The structure of the device is more compact, and the telescopic oil cylinder plays a role of the counterweight, thus enabling stress of the turntable to be more reasonable.