Objective: to remove oil, dirt, rust on the surface of the workpiece, and generate a layer of corrosion in workpiece surface and increases the "phosphate layer" of spraying coating adhesion.
The main process steps: oil removal, rust removal, phosphating, passivation.Artifacts after prior treatment not only surface without oil, rust, dust, and generated on the surface layer of the original silver luster evenly and coarse gray phosphating film is not easy to rust, both can rust and can increase the coating layer adhesion.
Common pretreatment are immersion and spray type two kinds, immersion need multiple dip tank;Spray is required on the coating line set up a spray line.
2, electrostatic spraying,
Purpose: spray powder coating evenly onto the surface of the workpiece, special artifacts (including prone to the location of the electrostatic shielding) high-performance electrostatic spray molding machine should be used to complete the painting.
Process steps: Using the electrostatic adsorption principle, on the surface of the workpiece evenly spray a layer of powder coating; After falling powder recovery by recycling system, sieving can be used again
3, high temperature curing
Objective: powder coating on the surface of the workpiece is heated to the specified temperature and heat preservation time, make it melt and flow flat, curing, we want to surface of workpiece is obtained.Process steps: good spraying workpiece pushed curing furnace, heating to a predetermined temperature (generally 185 degrees c), and heat preservation time (15 minutes);Blowing in remove cooling the finished product.
Tip: 1, curing furnace by "heating system" and "heat preservation box" two parts, which contains "heating system" control system. 2、Curing link can be used in a box solidification furnace (can choose to open the door at one end or both ends to open the door);Baked road (also can be used by type spraying production line, the workpiece at a certain speed through constant temperature drying, complete curing).
4, decoration processing
Objective: to make after electrostatic spraying the workpiece to achieve a kind of special appearance such as: all kinds of wood, decorative pattern, whitening, etc.
Process steps: hood light;Transfer printing process, etc.