L68B1 Mast Section How can the lifting arm of a tower crane achieve amplitude variation
The variation of the tower crane with boom type lifting arm is realized by changing the tilt angle of lifting arm. The advantage is that the arm frame is light(mainly subjected to compression loads), the amplitude is simple, and the tail radius of the turntable is small, which is suitable for use at sites with narrow and surrounding obstacles. The disadvantage is that the load variation is unstable. Due to the limitation of inclination, the effective range is about 70 % of the maximum range.
L68B1 Mast Section L68B1 mast section good at in this field
A tower crane with a horizontal weight lifting arm is realized by running a small car on the weight lifting arm. The advantage is that it can make full use of the range and can be driven close to the tower. Can achieve steady lifting weight, accurate location. However, due to the larger bending moment and compression force of the lifting arm, the lifting arm structure is bulky. Under the same conditions, the lever lifting arm is 18 % ~ 20 % lighter than the car variable lifting arm. In addition, when the building is higher than the crane hinge contact, the horizontal trolley Crane can not work.
L68B1 Mast Section L68B1 mast section good at in this field