Precautions for Using the Hook

The hook is a commonly used lifting device and is widely used in lifting machinery.

Types of hooks

1.Depending on the manufacturing method, hooks can be divided into forged hooks and plate hooks.

1. Forged hooks are generally made of high-quality carbon steel, which is forged, stamped, annealed, and then machined. Forged hooks can be made into single hooks and double hooks.
2. Plate hooks are generally used for lifting machinery with larger lifting capacity. The plate hook is made of 30mm thick formed plates overlapped and pinned together. The plate hook is equipped with a guard plate, which is generally made of steel plate rolled from Q235A, Q235B or 16mn steel. Plate hooks are also divided into single hooks and double hooks. Single hooks are mainly used for casting lifting machinery.

2.The cross-sectional shapes of the hook include rectangular, trapezoidal and T-shaped. Cranes usually use single or double hooks with trapezoidal cross-sections; rectangular cross-sections are generally plate hooks; electric hoists usually use T-section hooks. There is a certain relationship between the main dimensions of the hook, for example: between the opening degree S and the hook hole diameter D, S=0.75D.

Precautions for safe use of hooks

1. The hooks should be produced by regular professional manufacturers in accordance with the technical conditions and safety specifications of the hooks. The products should have the manufacturer's quality certificate, otherwise they shall not be used.
2. New hooks should be subjected to a load test and can only be used after passing the test. The measured hook opening should not exceed 0.25% of the original opening.
3. During use, the hook should be checked frequently for cracks, severe deformation, corrosion and wear.
4. The hook should be tested once a year. During the test, a static test is carried out for 10 minutes at 1.25 times the allowable working load, and then a magnifying glass or other method is used to check for cracks, notches and residual deformation.
5. The dangerous section should be cleaned with kerosene and checked with a magnifying glass for cracks. The plate hook should be checked for wear on the bushing and pin.
6. If there are defects on the hook, no repair welding is allowed.