The hooks can be made of 20 high-quality carbon steel or forged with special materials such as DG20Mn and DG34CrMo. It is strictly prohibited to use cast hooks. The plate hook is generally made of A3 and C3 ordinary carbon steel or 16Mn low alloy steel. The longitudinal axis of the hook plate must be located in the rolling direction of the steel plate, and the hook plate is not allowed to be spliced. The hook piece of the plate hook shall be riveted with countersunk rivets, and the high stress bending part where the plate hook contacts the lifting point of the lifting object shall not be connected with rivets.