The content of the process design mainly includes: the pretreatment method of the surface coating quality requirements of the workpiece, the spraying method, the process flow, the coating performance, the spraying environment, and the time.

1. Purpose of painting:

Through coating construction, the coating can form a firm and continuous coating on the surface of the object to be coated to play its role in decoration, protection and special functions.

1.1 Painting elements

The key to the painting project is: painting process and equipment, painting materials, working environment, and painting management.

The quality of the materials to be coated is the basic condition for obtaining high-quality coatings. The coating process, equipment, and coating environment are necessary conditions for giving full play to the performance of coating materials, obtaining high-quality coatings, reducing production costs and improving economic benefits. Coating management is an important condition to ensure the implementation of the established process, to ensure the stability of the coating quality, to achieve the coating purpose and the best economic benefits.

2. Main equipment for painting

The main equipment for painting is divided into surface pretreatment equipment before painting, painting equipment, coating film drying and curing equipment, mechanized conveying equipment, dust-free constant temperature and humidity air supply equipment and other auxiliary equipment.

2.1 Coating surface pretreatment equipment

2.1.1 Purpose of preprocessing:

Removal of foreign matter, such as oxide scale, rust spots, grease, etc., on the coated parts, and provide a good substrate suitable for coating requirements, such as phosphating, oxidation, and passivation, to ensure that the coating has good anti-corrosion and decorative properties.

2.1.2 Pretreatment equipment is mainly divided into physical type and chemical type.

Physical formula:

①Remove impurities adhering to the surface of the steel plate, and use a thinner to remove grease and other dirt.

②If there is sulfate or corrosive salt, it should be washed with clean water and dried with compressed air.

③On the steel plate pretreatment line, use shot blasting or sand blasting to remove oxide scale, rust and other impurities, and then use a vacuum cleaner or purified compressed air to remove the surface of the steel.

Chemical formula:

Immersion type, spray type, combination of immersion and spray, combined type of spray-immersion-spray.

It is mainly composed of tank body, tank liquid heating system, ventilation system, tank liquid stirring system, phosphating slag removal system, oil-water separation system, etc. Among them, phosphating slag removal and oil-water separation device are the key systems. Phosphating slag removal includes sedimentation method, hydrocyclone separation method, inclined plate sedimentation method, bag filter method, plate and frame filter press and other common methods. Oil-water separation mainly includes: adsorption method, ultrafiltration method, hot oil separation method and centrifugal method.