For large work lifting or assembly in place, because of large tonnage, complex, expensive, many people with other factors, to further improve the operation difficulty and risk coefficient, therefore, in large sling work, should grasp and seize the following essentials:
1. Before work, observe the appearance of the workpiece, grasp the center of gravity of the workpiece, and confirm the weight of the workpiece according to the drawing.
2, the correct choice of ropes, shackles, hooks and other rigging. When the steel wire rope is selected, the tensile force of the single rope can be calculated according to the empirical formula of S (Newton) =100*d2. Of which: D is the diameter of wire rope, and the unit is mm.
3 of the work itself, for the lifting and the design of rings or lugs, should be carefully examined before operation, and in all the rings on the caucasus.
4, the work itself does not have rings, should correctly select the location of the cable point. The crane's hook head is aligned with the center of gravity of the work.
5, pay attention to the angle between the rope, generally should be less than 90 degrees.
The 6 corners, rope passes through the angle of protection must be added.
7, before lifting, you should have a test hanging process, confirm the security, and then proceed to the next step.