How to spray paint on the electric hoist hook after it falls off?

During the use of electric hoists and crane hooks, the working surface often comes into contact with steel wire ropes, steel buckets, and the hooks of pouring ladles due to wear and tear, making it easy to scrap them in advance, resulting in material waste and economic losses. However, according to the safety regulations for lifting machinery, welding repair is not allowed for the use of hooks. Therefore, a new method is proposed to repair the wear or paint peeling of hooks, in order to improve utilization and extend service life.

The spray repair methods for hooks can be divided into two types: spraying and welding.

1、 Spray coating method

The spraying method is to use an oxygen acetylene spray welding gun to grind and spray an automatic exothermic alloy powder onto the rough and worn surface of the lifting hook. The powder undergoes a strong exothermic reaction under the heating of the oxygen acetylene flame, producing an instant high temperature. It undergoes atomic motion, diffusion, and bonding with the base material, forming a transition layer. Then, according to the requirements of the working conditions, spray the corresponding self fluxing alloy powder to form a working layer with mechanical properties such as wear resistance.

2、 Spray welding method

Spray welding method is to use a spray welding gun, relying on an oxygen acetylene flame, to spray the corresponding self fusing alloy powder onto a pre heated and clean hook worn surface according to the working conditions. Then, the spray welding layer is heated and remelted with an oxygen acetylene flame or other heat source, welded with the base metal, forming a welding layer with mechanical properties such as wear resistance.

The spray repair of the working surface wear of the electric hoist hook has the advantages of simple process, small deformation, good quality, and a large amount of material savings. Especially after the wear of the hook, welding repair is not allowed. The spray repair method has the unique advantage of improving the service life of the hook. Spray welding has higher bonding strength than spray welding, and the welding layer has no pores, making it suitable for repairing large lifting hooks with heavy load-bearing capacity and high wear. Although the bonding strength of spraying is lower than that of spray welding, it is still more than twice that of traditional metal spraying. The pores of the porous layer can store oil and improve the wear resistance of the surface (working layer). Compared with spray welding, spray welding has the characteristics of small deformation and high fatigue strength.