Process & Dry Times:
1. Surface pretreatment, mainly chrome (aluminum), bismuth (iron, etc.), sandblasting, etc.
2. Protection (also called cover). If some parts of the workpiece are not required to be coated, they can be covered with protective glue before preheating to avoid spraying.
3. Preheating, generally no need to preheat. If the coating is required to be thick (150-300 film thickness), the workpiece can be preheated to 180-200 ° C, which can increase the coating thickness.
4. Spraying, in the high-voltage electrostatic field, the powder gun is connected to the negative pole, and the workpiece is grounded (positive) to form a loop. The powder is sprayed out by the spray gun with compressed air, which has a negative charge, and is sprayed onto the workpiece according to the principle of opposite-phase suction.
5. Curing, the workpiece after spraying is sent to a drying room at 180-200 ° C for heating, and a constant temperature of 15-20 minutes is reserved to completely cure the powder.
6. Clean up. After the coating is cured, remove the protector and smooth the burrs.
7. Inspection. Check the coating of the workpiece. Any leaks, bumps, needles and other defects should be reworked.
8. Defect processing. Rework or re-spray of the detected workpiece with missing spray, pinhole, bump, bubble, etc.