With the development of industry, China's industrial manufacturing technology has risen several steps, and the technological requirements for surface treatment have also increased. Electric paint sprayer is a common spraying machine at present.
Electric paint sprayer refers to a coating method that uses corona discharge principle to make atomized paint negatively charged under the action of high-voltage direct current electric field and adsorb on the surface of positively charged substrate to discharge. Electric paint sprayer consists of spray gun, spray cup and electrostatic spraying high voltage power supply.
Most of the film-forming materials in the coating, i.e. resins and pigments, are composed of high molecular organic compounds, mostly conductive dielectrics. Besides the film-forming materials, solvent-based coatings also contain organic solvents, cosolvents, curing agents, electrostatic diluents, and other additives. Except benzene, xylene and solvent gasoline, these solvent substances are mostly polar substances with low resistivity and certain conductivity. electric paint sprayer can improve the charging performance of coatings.
The molecular structure of dielectrics can be divided into polar molecules and nonpolar molecules. Dielectric composed of polar molecules shows electrical properties when subjected to applied electric field. Dielectric composed of nonpolar molecules is better outside.
The coating is sprayed out after being atomized by the nozzle, and the atomized coating particles are electrified due to contact when passing through the edge of the pole needle or spray disc of the muzzle and the spray cup, and when passing through the gas ionization region generated by corona discharge, the surface charge density of the atomized coating particles will be increased again. Under the action of electrostatic field of these negatively charged coating particles, the surface of the workpiece with guiding polarity moves and is deposited on the surface of the workpiece to form a uniform coating film.
If we want to use electric paint sprayer, we need to start with the data such as the wind speed in the paint booth, the spray gun, the resistance of the paint, the viscosity of the paint, the air pressure, the paint pressure, the output parameters, etc.