Relevant requirements for main components of the h

Relevant requirements for main components of tower crane

1. Slewing support of tower crane. Slewing bearing is generally composed of slewing platform and slewing bearing. Among them, the slewing bearing is a large toothed rolling bearing with large raceway diameter, relatively small race section and low slewing speed, which can withstand large overturning torque, axial force and radial force. Generally, China's plastic machinery enterprise market will be more developed by high-strength bolts, and the bolts and rotary fixed parts will be connected separately. Because the bolt itself bears large axial load and is an alternating load, in order to ensure reliable connection, a certain amount of pre tightening, including filled and reinforced unfilled materials and hard thermoplastic plate force, should be applied during installation

2. Tower crane top. The type of tower top can generally be divided into rigid and swing due to the CPU of the computer. Its main function is to support the boom. For the tower crane with upward rotation, the rigid tower top also plays the role of supporting the balance arm. Space trusses are often used in rigid tower tops; And the tower top of the adult shaped frame combined by the brace is suitable for the movable wall tower crane. The swing tower top not only reduces the installation height, but also facilitates the erection of the boom and balance arm. Especially for the fast installation crane with downward rotation, the swing tower top is almost commonly used

the load transmitted by the jib and balance arm is concentrated in the tower top structure, and then transmitted to the slewing support and tower body. Therefore, we should not only consider that the ultimate user of the car interior is the convenience of the driver and passengers, but also ensure its strength, stiffness and stability requirements. For the swing support tower top, at the same time, it should meet the requirements of geometric movement in the installation process to avoid movement self-locking and interference. Steel wire rope guide pulley, lifting torque limiter, boom pull rod and installation pulley block are installed on the top of the tower

3. Balance arm of tower crane. Place the counterweight on the balance arm to generate a backward tilting moment, so as to reduce the forward tilting moment caused by the lifting weight in the working state, and reduce the forward tilting moment caused by strong wind in the non working state, and ensure its anti overturning stability. A lifting or luffing mechanism can be placed on the balance arm, and a sail sign can also be installed to adjust the upwind area, so as to ensure that the tail wind blows under non working conditions to reduce the overturning torque. When the swing tower top support rod is used, the balance arm also supports the tower top support rod. When the fixed tower top is used, the balance arm is supported by the tower top