新闻中心
Location:Home / News /Common Sense / 正文
Cabinet electrostatic spraying process principle
DATE:2014-5-28   VISITORS:4024

A surface pretreatment
Pretreatment process quality directly affect the quality of powder coating, pretreatment is bad, cause coating is easy to fall off, the phenomenon such as bubbling. Therefore, before work must attach importance to it.
(1) can be used for sheet metal stamping chemical pretreatment method. Namely: to oil and rust - cleaning - phosphate (or purification) and so on. Most rust or thicker the surface of the workpiece, the sandblasting, shotblast machinery method to rust, but after the mechanical cleaning should ensure that the workpiece surface is clean, not scale.
(2) blow be bored with child. According to the workpiece surface defect degree conduction putty, dry with sand paper after grinding smooth, next working procedure can be achieved.
(3) protection (also known as cap). If some parts are not required to have coating on artifacts, in front of the preheating can be used to protect the gum, cover up, to avoid the spray coating.
(4) preheating. Generally don't need to preheat. If the required coating thicker, artifacts can be preheated to 100 ~ 160 ℃, this will increase the coating thickness.
Spray.
Artifacts by transmission chain into spray room spray gun position for spraying operations. Electrostatic generator by spray gun muzzle needle electrode to the direction of the workpiece space release high-voltage electrostatic (cathode), the high voltage static electricity from. Spray gun mouth spit out of powder and mixture of compressed air and surrounding air ionization electrode (negatively charged). Artifacts after hanging fixture by transmission link ground (earth), thus in an electric field between the gun and workpiece powder in the electric field force and reach the surface of the workpiece dual driven by compressed air pressure, depend on the electrostatic attraction in form a uniform coating layer on the surface of workpiece.
3. Bake for curing
After spraying the workpiece through the conveyor chain into heating within 180 ~ 200 ℃ drying room, and the corresponding time, heat preservation (15 to 20 minutes), melting on the surface and curing, we want to surface of workpiece is obtained. (different powder on the baking temperature and time are different). This is on the curing process should pay attention to.
4. Clean up.
The coating after curing, remove the protection content, make the burr.
5. Check
After curing the artifacts, main daily check appearance (flat light, do you have any particles, such as shrinkage cavity defects) and thickness (control in 55 ~ 90 microns). To be detected with leakage, pinhole, bruising, bubble defects such as artifacts, for repair or spray.

PARTNER: