Process flow of surface pretreatment of iron billet of glass-lined reactor

The main functions of metal material surface pretreatment include two aspects:

1. Remove the greasy dirt, rust and oxide on the surface of the metal body, and make it no longer rust in a short time, so as to obtain the surface quality meeting the coating requirements.

2. Due to the deformation of the internal grain structure and residual stress of the metal body after deep drawing

Annealing treatment can help to eliminate the stress in the iron damage and remove part of the surface carbon, thus reducing the deformation, black lines, edge cracks, bubbles and pinholes and other defects caused by the stress in the metal damage. Generally, annealing is not required for iron damage with low residual stress.

The pre-treatment of the damaged metal body has a direct impact on the quality of Tang porcelain products. If the damaged metal body after treatment has oil dirt and rust, it will make it difficult to apply the primer or fall off after drying, and there will be burning shrinkage when firing, and it may also produce defects such as bubbles, pinholes, and poor adhesion.

There are three main methods for surface pretreatment of metal materials: degreasing acid washing, oil burning acid washing and oil burning sand blasting.