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The Use Of Hooks Has Very Strict Requirements Sep 13, 2017

The lifting hook is one of the main lifting parts in hoisting equipment, which plays a very important role in lifting heavy weights. Usually, the crane will choose the lifting weight of the hook according to the weight of the lifting, this is to ensure that the heavy load in the process, Lifting Hooks not because the heavy weight to cause the crane dangerous, therefore, the use of the hook is very stringent requirements. Below to understand the next, the safety of the use of the hook what are the requirements?

1, hook positioning bolts, open pins, thrust bearings above the nut fastening intact, reliable connection;

2, hook use must be perpendicular to force, Lifting Hooks strictly prohibited transverse force;

3, hook thread in the rotation must be tightened, in order to prevent loose off the hanging objects;

4, the use of two rings at the same time work, two of the angle of the lifting surface should not be greater than 90 degrees.

5, lifting lifting operation of the use of hooks, Lifting Hooks rings require smooth surface, no break, spalling, nicks, sharp corners, seams and cracks and other defects;

6, the hook is not allowed to use the overload;

7, the hook should be able to rotate flexible;

8, hook deflection angle should not exceed 10 degrees

9, the use of hooks and heavy lifting rings connected, must ensure the position and force of the hook to meet the requirements;

Hooks are generally forged or stamped, but also with a number of plates riveted, can not be used to create lifting hooks.

The former is called the forged hook, Lifting Hooks the latter calls the hook. The material of forging hook is commonly used in 20th # High quality carbon steel (open hearth);

The material of the plate hook is commonly used for 20th high quality carbon steel, and the thickness of the plate is not less than 20 mm.

After forging or stamping, the hook must be treated with accurate annealing to eliminate the residual internal stress and increase its toughness, Lifting Hooks and the surface hardness should reach 95~135HB.

When the hook is subjected to load, the internal crystal structure is partially produced by sliding, and the residual stress is not restored after unloading, so the so-called cold hardening phenomenon is formed.

In order to eliminate residual stress in hardened area and restore original toughness, Lifting Hooks accurate annealing process is also needed.

The hooks used in the construction of transmission lines shall be treated in accordance with the relevant regulations in addition to regular inspection.

The forged single hook is commonly used in transmission line construction.