L68A1 Mast Section the requirements for the installation method of tower crane attachment device
The length of each strut of the structural part of the tower crane attachment device can be adjusted, and each strut shall be kept in the same plane, and the length of the top block and strut shall be adjusted to make the axis of the tower vertical. After general attachment, the verticality of the tower crane axis line shall be checked and adjusted by theodolite. The verticality of the tower body below the attachment point shall not be greater than 2 / 1000, and the verticality above the attachment point shall not be greater than 3 / 10000. The verticality can be adjusted by adjusting the advance and retreat of the bolts on the stay bar.
The installation of the attachment device of the tower crane shall meet the requirements of the instructions of the tower crane. The erection spacing of the attachment device and the free height above the attachment point shall not be arbitrarily overlong (the specific attachment point is allowed to be adjusted within 1m according to the actual situation of the building). The extra long attached strut should be designed separately and checked for strength and stability.
The first attachment of the tower crane is 24m from the foundation surface. With the increase of the section of the tower crane, the corresponding attachment times will be increased. The maximum cantilever height of the tower crane shall not exceed 27m.
When the attachment device of tower crane is installed, the two half frames are sheathed on the standard section, and the standard section is clamped by 16 M20 connecting bolts between the two half frames, and then the tower body is supported by the strut. The attachment device connects one end of the attachment strut with the attachment frame through the pin shaft, and the other end with the embedded parts fixed on the building to form a stable attachment structure.
The frame sleeve (also known as ring beam sleeve) is welded by angle steel and steel plate. When in use, the frame is sleeved on the standard section. The four corners are fixed with 8 adjusting bolts through the top block, and the attachment frame is positioned on the standard section through 4 holding hoops under the frame. The frame is connected with the building through 3 or 4 struts. The connection point between the struts and the building shall be selected on the concrete column or concrete ring beam. The embedded parts shall be combined with the concrete, and the embedded parts or wall bolts shall be connected with the building structure.
It is very dangerous to use expansion bolt instead of embedded parts or cable wind rope instead of attachment support, because the attachment device and its accessories are the same as the standard section, which belong to the manufacturer's products, and the use of substitutes reduces the strength and stability of the attachment device.
