Is it necessary to adjust the height limiter when the tower crane is raised?

The following is the tower crane jacking and attachment scheme.

Tower crane jacking For today's horizontal boom tower crane, the extension of the front boom and the rear balance arm is larger, and the unbalanced bending moment is caused to the center of the tower. In addition, the weight of the upper part of the tower crane is also larger, and the weight of the upper part of the QTZ80 tower crane and QTZ125 tower crane is about 35t.

1. The operation procedure of the tower crane jacking work There is a jacking sleeve in the upper structure of the tower crane, which is set outside the standard section of the tower body, and the height is greater than 2 standard sections of the tower body, and a large introduction window is opened on the upper side of the front side, and a standard section can be introduced.

At the time of jacking, with the support of the sleeve, the hydraulic pump station is started to work, so that the piston rod in the cylinder stretches out, and the tower crane superstructure is jacked, so that a standard section is introduced or removed from the window, and the tower crane is raised or lowered. Fig. 1 is a schematic diagram of the hydraulic jacking process of a cycle of tower crane. The descent process is reversed.

2. The requirements in the jacking procedure and the balance of the safety link adjustment: The structure of the upper part of the tower crane forms a bending moment to the center of the tower mast: the bending moment in the backward direction formed by the counterweight block and the counterweight arm and the winch mechanism above, and the bending moment formed in the forward direction is mainly the crane arm, the torque of these three parts to the axis is stationary and cannot be changed, and the trolley on the crane arm can move, and the bending moment formed by the front boom can be changed.