and balance arm fused hammerhead-type level luffing jib car. Single hanging point is statically determinate structure, twin-lift point is statically indeterminate structure. Hammerhead-type trolley level luffing jib installed at the tower top Zhuangruo hammer, shaft, such as hammer handle, no spire, it is also known as flat head style. Flat-style of making structure simpler and more conducive to the force, to reduce weight and simplify construction and so on. Most used car luffing jib equilateral triangle cross-section.
Tower structure, also known as the tower is the main body of the tower crane structure. Now adopt a square cross-section of tower crane, application of a broader cross-section dimensions are: 1.2m × 1.2m, 1.4m × 1.4m, 1.6m × 1.6m, 2.0m × 2.0m; tower section used the standard size is 2.5m and the 3m. Tower sections used in the standard connection method is to cover the most widely used set of stud bolt connection and connection, followed by the pin connection and flashboard pin socket connection. Standards Section has the overall standards of style tower-type tower sections and assembled the standard sections, the latter high precision machining, production difficult, but the stacking area is small, less freight. Ladder tower section must be set so that driver and mechanic from top to bottom. Ladder width of not less than 500mm, ladder step spacing of not more than 300mm, set up a guard ring for each 500mm. When the ladder height of more than 10m, the ladder should be
sub-switching, the switching office to install a closed platform. Spire function is to bear arm and balance arm Cord Cord coming from the upper load, and through rotating tower, turret, bearings and other structural components-style passing directly through the turret to the tower structure. Since l have truncated conical tower column, forward or backward truncated cone column, Renzi Jia style and bracing Shelf. Any slewing tower cranes are required to set up a balance weight, its function is to balance the weight bearing, which constitute the design required by the role of torque in the opposite direction and lifting the balance of torque. In addition to balance the weight, but also often installed in its rear lifting mechanism. Lifting bodies are placed, together with the balance weight arm in balancing the tail end of a re-allocation of the Department can play a role, two rope reel and the spire increase the distance between the guide wheel to facilitate the rope around and avoid the occurrence of emission the phenomenon of chaos rope. Balance the weight and balance amount is inversely proportional to the relationship between the length of the arm, while the balance of arm length and boom there is a certain percentage of the length of the relationship in between. Balance the considerable amount of heavy, light tower crane usually at least 3 ~ 4t, heavy to almost 30t. Balance weight can be made of cast iron or reinforced concrete: the high cost of the former process, but the small size wind; the latter were large in size to the
stability of the windward big negative, but the simple economy, it is generally use this. The usual practice is to balance the emphasis on pre-divided into 2 ~ 3 kinds of specifications, width, thickness of the same, but the
height should be adjusted to match the use of different arm lengths. (B), the tower crane spare parts
Each tower crane must be used in many kinds of lifting parts, of which the largest number of technical requirements are strict and complicated rope specifications. Tower crane wire rope used in accordance with different functions are: lifting wire rope, rope luffing, jib ropes, balance the arm ropes, trolleys and other traction rope. Steel wire rope is characterized by: the entire root, high strength, but also the whole root sections, the size of the same intensity, light weight, able to withstand shock loads, flexible enough to winding into a disk, can be balanced at high speed movement, and no noise, wear and tear After the skin will produce a number of glitches, easy to detect and facilitate the timely disposal. Steel wire rope is usually a Unit diameter 0.3 ~ 0.4mm thin twisted wire strand, and then twisted into rope by the Unit. Tower crane is used in interactive twist, is characterized by loose and difficult to reverse. On the strand cross-sectional shapes, the high-rise building construction with the tower crane to adopt the multi-strand rope is not reversed, the most appropriate, such a wire rope consists of two layers
composed of the same strand, two strand twisting in the opposite direction, using the principle of rotating torque balance twist crafted by force does not occur when the free end of the reverse. Hoisting Tower Crane luffing rope and wire rope safety factor usually taken to be 5 ~ 6, car towing rope, and boom Cord of the safety factor of 3, tower crane lifts Lifting Sheng An all-coefficient of not less than 10. Steel wire rope safety factor is indispensable for security reserve factor, by virtue of this security must not be arbitrarily raised the rope reserves face the maximum allowable safe load. Because of the importance of steel wire rope, we must strengthen the comprehensive inspection of wire rope on a regular basis, stored in dry closed surface, there are wooden floors or asphalt concrete warehouse floor to prevent corrosion, loading and unloading not to damage the surface of the pile when placed erect. Systematic lubrication of the rope can increase the service life. Luffing jib tower crane trolley is the level of essential parts. Change car set by the frame structure, steel wire rope, pulleys, line wheels, guide wheels, steel wire rope supporting the wheel, steel wire rope anti-roll off, car towing rope tensioning device and the broken rope composed of insurance, etc.. For the talent level of boom (more than 50m in length) in amplitude with the car at the side of an overhaul hanging baskets may contain members of the maintenance and repair of all maintenance points to the repair and maintenance. Job finished, the roots boom car driven
