What Is a Lifting Hook?
Lifting hook, English name lifting hook, is the most common type of lifting gear in lifting machinery. The hook is often suspended on the wire rope of the lifting mechanism by means of a pulley block and the like.
Hook safety inspection
- 1. The hooks for human-driven lifting mechanisms are tested with 1.5 times the rated load as the inspection load.
- 2. The hooks for the power-driven lifting mechanism are tested at twice the rated load as the inspection load.
- 3. After the hook is unloaded to inspect the load, there should be no obvious defects and deformations, and the increase in opening should not exceed 0.25% of the original size.
- 4. For hooks that pass the inspection, a mark should be printed in the low-stress area of the hook, including the rated lifting weight, factory logo or factory name, inspection mark, production number, and so on.
Hook scrap standard
- Hooks should be scrapped when one of the following occurs:
- crack;
- Dangerous section wear is 10% of the original size;
- The opening degree is increased by 15% than the original size;
- The torsional deformation of the hook body exceeds 10 °;
- Dangerous section of hook or plastic deformation of hook neck;
- The hook thread is corroded;
- When the cymbal hook bushing wears to 50% of its original size, the bushing should be replaced;
- When the cymbal hook mandrel wears down to 5% of its original size, the mandrel should be replaced.
Precautions for safe use of hook
- 1. The hook should be manufactured by a formal professional factory in accordance with the technical conditions and safety requirements of the hook. The product should have the quality certificate of the manufacturer, otherwise it is not allowed.
- 2. The new hook should be subjected to a load test, and the measured opening of the hook should not exceed 0.25% of the original opening.
- 3.The hook should be checked frequently for cracks or severe deformation, corrosion and wear during use.
- 4. The hook should be tested once a year. During the test, perform a static test at 1.25 times the allowable working load for 10 minutes. Check with a magnifying glass or other methods. There should be no cracks, rips or residual deformation.
- 5. The three dangerous sections should be cleaned with kerosene and checked for cracks with a magnifying glass. For plate hooks, check the bushings and pins for wear.