There are many methods of construction of paint, most of which are used for springs in the following ways:
(1) dip coating method dip coating method is to dip the spring into the paint groove, and then take out, and let the excess paint on the surface drip naturally. After drying, it is covered with paint film on the surface of the spring.
The dip-coating method has high production efficiency and can be applied to mechanization and automation production.But the paint volatilizes quickly, the paint that contains heavy quality pigment and two component paint material (amine solidify epoxy paint, polyurethane paint etc.) should not be used.Dip coating film is not smooth enough, easy to produce thin and thick, edge flow.
(2) spraying method spraying is to use the spray gun to spray the paint into tiny mist particles and uniformly deposit a layer of paint film on the spring surface.
Spraying method has high efficiency, convenient construction and strong adaptability, and the film thickness is relatively uniform, smooth and smooth.However, the effective utilization rate of spraying method is only about 70% to 80%, and more solvents are needed than other methods. These solvents will be volatilized and the loss is too great.In addition, the diffusion of paint mist particles and volatile solvent, resulting in environmental pollution, affecting the health of workers.
(3) at the moment when the thermoset powder passes through the mouth of the spray cavity by electrostatic spraying, the negative charge is induced and the plastic powder is evenly applied on the surface of the spring under the action of compressed air.Then spray is good spring of 150-180 ℃ temperature in the oven heat insulation (plastic), to form a smooth solid surface protective layer, general heat preservation time of 40-60 min.
This process has the advantages of high efficiency, good flow production, good product quality, uniform film thickness and good adhesion.
(4) other methods: with the changes in the host structure and the increasingly harsh operating conditions of the spring at work, in order to improve the service life of the spring, the surface corrosion prevention treatment such as the valve spring was changed to replace the traditional oxidation or coating treatment with special rust prevention oil (grease) after the spring cleaning.
