As the powder coating does not contain organic solvents and water, a solid powder state, this feature determines its construction method is clearly different from the traditional solvent-based coatings and water-soluble coatings. The spraying process can be divided into two kinds of thermal spraying and cold spraying. Thermal spraying is by heating the powder coating is melted, and then applied to the workpiece and the formation of smooth coating. The cold spray is at room temperature with a variety of methods to the powder coated to the workpiece, and then use the heating or radiation curing method to make the coating hot melt, leveling and the formation of a good coating method. Which is sprayed powder electrostatic spraying method, according to the principle, can be divided into high-voltage electrostatic spraying and friction electrostatic spraying two, the equipment is also divided according to these two. High pressure powder electrostatic spraying equipment In the high-voltage electrostatic spraying powder, the same with the solvent coating is to be in the electrostatic spray gun and Between the workpiece to exert high-voltage electrostatic, spray gun and electrostatic field connected to the negative, the workpiece connected with the ground. The difference is that the powder coating is in the role of purification of compressed air, from the powder feeder through the powder into the powder powder spray gun. A metal ring with a sharp edge on the gun head or a pin as an electrode. When the electrode is connected to high voltage static electricity, it will produce corona discharge, and in the vicinity of the electrode to produce a dense negative charge. When the powder coating is ejected from the head of the electrostatic spray gun, it is charged and charged negatively, flying to the workpiece under the action of airflow and electric field and adsorbing it on its surface. Friction powder electrostatic spraying equipment Friction Electrostatic Spraying No high voltage electrostatic generator for high voltage electrostatic spraying is required, and there is no need to establish a high voltage electrostatic plant between the powder gun and the workpiece. The key lies in its powder spray gun made of strong negative material, when the two kinds of negative electricity of different materials Material friction, weak negative material will bring positive electricity, and strong negative material will bring negative electricity. In the case of a powder coating using a weakly negative film-forming material, the collision between the powder coating particles and the friction between the powder and the gun body made of the ferroelectric material causes the powder particles to be positively charged. So the choice of the appropriate material in the production of guns, the powder in the compressed air driven by the movement in the gun when the friction and bring a positive charge in the air flow continued to push, will fly to the ground of the workpiece and be adsorbed On this layer of loose coating after curing will form a uniform and smooth coating.