Hook technical requirements

1. The purchase of hooks must have technical documents such as certificates from the manufacturer before use; hooks purchased by important departments such as railways, ports, etc. must be strictly inspected (flaw detection) before leaving the factory.
2. The hook must not have defects that affect safe performance; hook defects must not be repaired by welding; the surface of the hook should be smooth and free of cracks, folds, sharp angles, burrs, peeling, overburning and other defects.
3. You can select two suitable positions to print non-wearable marks at the shortest distance from the hook opening, and measure the distance of the marks as a basis for detecting whether the opening degree changes during use.
4. The hook material can be forged from 20 high-quality carbon steel or special hook materials such as DG20Mn and DG34CrMo. The use of cast hooks is strictly prohibited. The material of the plate hook is generally A3, C3 ordinary carbon steel, or 16Mn low alloy steel.
5. The technical conditions of homemade hooks should comply with the regulations of GB 10051.1-88～GB 10051.5-88 (new standard: GB10051.1-2010～GB 10051.5-2010)
6. The longitudinal axis of the hook piece of the plate hook must be located in the rolling direction of the steel plate, and the hook pieces are not allowed to be spliced.
7. The hook piece of the plate hook should be riveted with countersunk head rivets, and rivets should not be used to connect the high-stress bending parts where the plate hook contacts the lifting point of the hoisted object.
8. Fully enclosed welding is not allowed between plate hook laminations, only intermittent welding is allowed.
9. Hooks that have undergone overload testing should be scrapped.