Pretreatment Equipment

Qingguo Intelligent is pretreatment equipment manufacturer and supplier in China who can wholesale pretreatment equipment. In the painting and powder coating process, pre-treatment equipment plays a crucial role. It mainly treats the surface of the workpiece, providing a good foundation for subsequent powder coating to ensure the adhesion and quality of the powder coating.

Degreasing equipment

Function:

The degreasing equipment used in pre-processing equipment is mainly used to remove grease from the surface of workpieces. In the industrial production process, the surface of the workpiece may be contaminated with various oil stains, such as cutting oil and rust proof oil used in mechanical processing. These oils can seriously affect the adhesion between powder coatings and the surface of workpieces. For example, after the processing of automotive parts, there will be a large amount of lubricating oil residue on the surface, and degreasing equipment can effectively remove these oils.

Composition and working principle:

Common degreasing equipment includes degreasing tanks and spray systems. The degreasing tank contains a degreasing agent solution, in which the workpiece can be immersed to decompose the grease through a chemical reaction between the degreasing agent and the grease. The spray system sprays degreasing agent solution onto the surface of the workpiece at a certain pressure through a nozzle to enhance the degreasing effect. There are various types of degreasers, including alkaline degreasers, organic solvent degreasers, etc. Choose the appropriate degreaser based on the material of the workpiece and the type of oil contamination.

Hydro-jet blasting

Function:

Rust removal equipment is used in pre-processing equipment to remove rust from the surface of workpieces. For metal workpieces, especially steel products, they are prone to rusting during storage or processing. The presence of rust can lead to weak adhesion between the coating and the workpiece surface, thereby affecting the protective performance of the coating. For example, if there is rust on the surface of steel bars used in construction and the coating is applied directly without treatment, the coating is easily peeled off.

Composition and working principle:

Chemical rust removal equipment mainly uses the chemical reaction between acid solution and rust to remove rust. There is usually an acid pickling tank where the workpiece is soaked in an acid washing solution (such as hydrochloric acid, sulfuric acid, etc.), and the rust reacts with the acid to dissolve in the solution. To prevent excessive corrosion of workpieces by acid solution, it is also necessary to control the concentration, temperature, and soaking time of the acid solution. Another type is shot blasting rust removal equipment, which uses a shot blasting machine to rapidly eject pellets onto the surface of the workpiece, using the impact force of the pellets to remove rust and oxide scale, while also strengthening the surface of the workpiece to a certain extent.

Phosphating equipment (for some processes)

Function:

Phosphating is a process of chemical and electrochemical reactions that form a phosphate chemical conversion film. Phosphating film can improve the corrosion resistance of the workpiece surface and the adhesion of the coating. In some industries with high requirements for coating quality, such as the automotive and home appliance industries, phosphating treatment is an important pretreatment step.

Composition and working principle:

The phosphating equipment mainly includes phosphating tanks. The phosphating tank is filled with phosphating solution, and the workpiece is immersed in the phosphating solution. Under certain temperature and time conditions, the metal on the surface of the workpiece reacts with the phosphating solution to form a dense phosphating film. The components of phosphating solution usually include phosphates such as zinc phosphate and manganese phosphate, as well as accelerators. Different phosphating solution formulas are suitable for different metal materials and process requirements.

Passivation equipment (used in some cases)

Function:

Passivation equipment is used to form a passivation film on the surface of workpieces, with the main purpose of improving the corrosion resistance of the workpiece surface. For some workpieces that have undergone rust removal or phosphating, passivation treatment can further enhance their corrosion resistance and help maintain the chemical stability of the workpiece surface.

Composition and working principle:

The passivation equipment used in pre-processing equipment is usually a passivation tank containing a passivating agent. After rust removal or phosphating treatment, the workpiece is immersed in a passivating agent, forming a very thin passivation film on the surface of the workpiece. The types of passivators include chromate passivators, chromium free passivators, etc. Chromate passivators have good passivation effects, but due to environmental issues, the application of chromium free passivators is becoming increasingly widespread.