品牌营销策划模板

Powder coating（powder spraying） is a type of coating that is applied as a free-flowing, dry powder. Unlike conventional liquid paint which is delivered via an evaporating solvent, powder coating is typically applied electrostatically and then cured under heat or with ultraviolet light. The powder may be a thermoplastic or a thermoset polymer. It is usually used to create a hard finish that is tougher than conventional paint. Powder coating is mainly used for coating of metals, such as household appliances, aluminium extrusions, drum hardware, automobiles, and bicycle frames. Advancements in powder coating technology like UV curable powder coatings allow for other materials such as plastics, composites, carbon fiber, and MDF (medium-density fibreboard) to be powder coated due to the minimum heat and oven dwell time required to process these components.

What are the technological processes of Powder coating?

1. Preprocessing

The quality of the pretreatment process directly affects the quality of the powder coating film. If the pretreatment is not good, the coating film is easy to fall off, bubbling and other phenomena. Therefore, the pretreatment work must be paid attention to.

Chemical pretreatment can be used for sheet metal stampings. Namely: degreasing → derusting → cleaning → phosphating (or purification), etc. For most rusted or thick surface workpieces, use sandblasting, shot blasting and other mechanical methods to remove rust, but after mechanical rust removal, ensure that the surface of the workpiece is clean and free of scale.

Scrape putty. Scrape the conductive putty according to the defect degree of the workpiece, and smooth it with sandpaper after drying, and then the next process can be carried out.

Protection (also called shielding). If some parts of the workpiece do not require coating, they can be covered with protective glue before preheating to avoid spraying paint.

Preheat. Generally, preheating is not required. If a thicker coating is required, the workpiece can be preheated to 100-160 °C, which can increase the coating thickness.

2. Spraying

The workpiece enters the spray gun position of the powder spraying room through the conveyor chain to prepare for the spraying operation. The electrostatic generator discharges high-voltage static electricity (negative electrode) through the electrode needle of the gun mouth to the space in the direction of the workpiece, and the high-voltage static electricity is generated. The mixture of powder and compressed air ejected from the nozzle of the spray gun and the air around the electrodes are ionized (negatively charged). The workpiece is connected to the ground (grounding pole) through the conveying tool through the hanger, so that an electric field is formed between the spray gun and the workpiece. The powder reaches the surface of the workpiece under the double push of the electric field force and the compressed air pressure, and forms a uniform layer on the surface of the workpiece by electrostatic attraction. coating.

3. Baking and curing

The sprayed workpiece is sent to the drying room at 180-200℃ through the conveyor chain for heating, and kept for a corresponding time (15-20 minutes) to melt, level and solidify, so as to obtain the desired surface effect of the workpiece. (Different powders vary in baking temperature and time). This should be noted in the curing process.

4. Clean up

After the coating has cured, remove the protector and trim the burrs.

5. Check

For the cured workpiece, the daily main inspection is the appearance (whether it is smooth and bright, whether there are defects such as particles and shrinkage holes) and the thickness (controlled at 55 ~ 90μm). Repair or re-spray the detected workpieces with defects such as missing spray, pinholes, bumps, and air bubbles.

6. Packaging

After inspection, the finished products are sorted and placed in transport vehicles and turnover boxes, and are separated from each other by flexible packaging buffer materials such as foam paper and bubble film to prevent scratches and wear (packaging can be made according to customer requirements)

The outstanding advantages of powder spraying process:

1. A thicker coating can be obtained with one coating. For example, a coating of 100-300 μm is used. With a common solvent coating, it takes about 4-6 coating times, while with a powder coating, this thickness can be achieved at one time. . The corrosion resistance of the coating is very good.

2. The powder coating contains no solvent and no pollution of the three wastes, which improves the labor hygiene conditions.

3. New technology such as powder electrostatic spraying is adopted, which has high efficiency and is suitable for automatic assembly line painting; the powder utilization rate is high and can be recycled.

4. In addition to thermosetting epoxy, polyester, and acrylic, there are a large number of thermoplastic grease-resistant coatings that can be used as powder coatings, such as polyethylene, polypropylene, polystyrene, fluorinated polyether, nylon, polycarbonate and various Fluorine resin, etc.

Applications of powder spraying process:

Powder coatings began to be used in protection and electrical protection. With the development of science and technology, they have been widely used in the automotive industry, electrical insulation, corrosion-resistant chemical pumps, valves, cylinders, pipes, outdoor steel components, steel furniture, castings, etc. surface coating.

Examples of Powder coating service

To provide customers with the best quality service