Views:4 Author:Site Editor Publish Time: 2017-03-03 Origin:Site
Block and tackle is a kind of simple mechanical equipment. In a block and tackle, it can easily change the direction of the force, and in use, how much save effort is usually determined by the string of the number of shares. The mechanical efficiency of block and tackle is by the gravity of the moving wheel, friction force and the gravity of the dragged object decision. In use of pulley block , should pay attention to the following items:
1, in strict accordance with the pulley of the safe use lifting weight, overload is prohibited. Pulley, the pulley block should have nameplate, indicating the size of the pulley, kinds and properties of lifting should be selected according to the requirements of nameplate pulley. As pulley is not marked weight, according to the thickness of the diameter of the pulley and shaft, jacketed wall thickness are calculated.
2, before the use should check the pulley groove, axles, plywood, hooks or rings and so on various parts, whether have the crack or damage. If found deformation and crack, pulleys, hook shaft positioning device is not perfect, is strictly prohibited . When lifting or handling equipment, when the pulley bearing, should check the operation condition of the moving parts, see any card rope, or wear rope place, such as is not satisfactory, shall be immediately adjusted.
3, where the stress direction is larger and aerial work, it is prohibited to use hook pulley, lifting pulley, should be adopted in case of decoupling. If the conditions limit, when need use hook pulley, must be add closure lock device on the hook .
4,When the lifting, pulley and steel wire rope must be equipped with appropriate. If narrow groove, wire rope, will cause the rim destroyed by extrusion wire rope, wire rope was serious wear and tear: if the groove is too wide, Wire rope force after get squashed, easily damaged, generally choose the diameter of wire rope groove width 1 ~ 2.5 mm is advisable.
5, in use of pulley block , it is forbidden to use the hand directly climbing the walking rope . At the same time in order to avoid because of wheel groove card master, should check whether the location of the wire rope traction direction and guide pulley is correct.