L48A1 Mast Section Structural characteristics of flat head tower crane
No tower head and tie rod is the most significant structural feature of the flat head tower crane, which is also the origin of the name of the flat head tower. Because of this special structure, there is a qualitative difference between flat head tower and tower crane with tower head, which also determines the unique advantages and disadvantages of flat head tower.
Compared with the luffing tower crane with the horizontal arm trolley with the tower head and the pull rod, the force condition and the connection mode of the flat head tower crane arm are obviously different. After the tower is erected, whether in working or non working state, the stress state of the upper and lower main chords of the crane arm and the balance arm of the flat head tower remains unchanged, the upper chords are mainly in tension, the lower chords are mainly in compression, without the influence of alternating stress, and the mechanical model is simple and simple. This is based on one point, the design of the flat head tower crane arm is more simple, which is very convenient for the quick disassembly and assembly between the arms. The modern flat head tower crane arm mostly adopts the space truss structure with triangle
section, which mainly considers this stress condition. The upper chord is connected by a pin shaft to bear the tension, and the lower chord is connected by the cross section of the joint to bear the pressure. In this way, the connection mode of the lower chord is very simple. Only two positioning locking pins and locking bolts are used. During installation, connect the upper pin shaft first, and then lower the arm joint. The two locking pins are automatically placed in place. Just put on the bolts. The arm joints are mainly connected by a large pin shaft of the upper chord, which is labor-saving and labor-saving. This is one of the characteristics of the flat head tower crane.
