Second, spraying process
1, spraying equipment and environment
1) Sprayer:
PVF coating can be applied by high pressure airless spraying and air spraying.
There are two types of spraying: mechanical spraying and manual spraying. Manual spraying equipment is simple, but the coating film thickness is not easy to uniform; mechanical spraying can achieve fully automated or semi-automatic operation, coating film is easy to uniform and improve efficiency.
Spray guns, domestic A800N type guns produced by Beijing Ruco Spray Measurement & Control Technology Co., Ltd. and series of spray guns produced by the United States Nordson Co., Ltd., applied by a number of manufacturers, the spraying effect is better, and the stability is also ideal, more suitable for PVF Paint construction features and process requirements.
Air spray method, the equipment is relatively simple, spray gun adjustment is more convenient and flexible. However, the paint is wasted, and the high-pressure air is easy to carry water with oil. Especially for wet areas in the south, degreasing and drying devices must be installed.
The high-pressure airless spray method directly pressurizes the paint to eliminate moisture and oil pollution. However, the coating properties (viscosity, fineness, etc.) are very strict and adjustment requires certain techniques.
In the case of high viscosity paints, the use of high-pressure airless spray is more appropriate, one spray can obtain a thicker coating.
2) Spray booth
It is no different from ordinary spray booths, but as much as possible with a device to recover paint. Unlike PVF paints and ordinary paints, PVF paints evaporate very slowly at room temperature. Exposure to the air will not harden or crust the surface. Scattered paints can be recovered and reused.
3) Scrubbing
PVF paint is different from ordinary paint, will not stick hands, does not solidify at room temperature, so contact with the paint utensils, tools, skin, clothes and need to re-spray the workpiece easily wipe or scrub with soap and water, alcohol can be.
4) Fixture
When designing the fixture, two characteristics of the polyvinyl fluoride coating should be considered: First, there is no stickiness, so the “wet†barrel parts are exposed to the bottom; second, the plasticized “dry†coating is re-softened by high heat. Therefore, when a barrel needs to be coated twice, do not bake the painted side on a shelf.
5) Construction site
To prevent dust, the slightly larger dust and metal dust fall on the “wet†coating and easily reach the bottom, affecting the protective performance.
2, spraying operation procedures
1) Preparation before production
aã€Check whether the sprayer and gas source are normal
b. After opening the PVF paint bucket, stir it
c. Check the paint for sedimentation, agglomeration, and debris, adjust the paint viscosity
d, whether the surface of steel drum is clean and dry
2) Spray operation
a, spraying operation, the pressure should be controlled at 0.20~0.30μPa,
b. The distance between the nozzle and the paint surface is 15~25cm.
c. Film thickness: It is not easy to spray too thick or too thin. When it is too thick, it will easily generate pits and water waves under the impact of air flow. It is also easy to cause sagging. When it is applied to the steel drum, it is generally used In the second baking process, the thickness of each coating can be controlled at 15 to 20 microns, and the thickness of the coating after the second coating can reach 30 to 40 microns. When steel drums are required to contain products with strong corrosivity or permeability, the thickness of the coating must be ensured. During the construction, the entire surface thickness should be evenly sprayed to improve the corrosion resistance.
d. Adjustment of construction viscosity: Polyvinyl fluoride coatings are still thicker than ordinary paints when they are left standing. Generally, they can be sprayed without adjustment. The stored liquid of the polyvinyl fluoride coating is precipitated on the upper layer, and it can be restored to its original shape without affecting the quality by simply stirring the rod before use.
If you find that spray atomization is not effective, you can take the following measures:
1, add a stirring device. Stir the paint thoroughly after spraying it.
2, install the thermostat. Normal temperature is set to 50-60°C, slowly heating, no overheating or local overheating. The appropriate temperature can be selected based on actual equipment conditions. This equipment is essential for winter in the northern regions.
3, if it is indeed too thick, you can add a small amount of dimethyl fat (added amount <5%), use after mixing well.
3) Precautions
1. Keep the spraying site clean and free of dust.
2, painted surface can not be bumped, touch.
3, if you find that the welding seam is not good, you need a brush or a spray gun.
4, when the second coating must be cooled before proceeding.
5, the coating can be cleaned with alcohol or soap, without the use of toxic organic solvents.
The LED Ceiling Light is widely used at Office, shopping mall, Hotel, showroom and so on.
The advantages for DiLin LED Ceiling Light
1. Fashion design with high quality of aluminum housing and constuction to make sure the cooling of LED Ceiling Light good enough.
2. High quality of COB and driver solution to make sure LED Ceiling light quality stable enough.
3. Strong Engineer & QC team are good at customizing and offer flexible solution for competitive Ceiling light.
4. Fast lead time: 5-7days for samples and 15-25days for bulk order.
5. 3 or 5 year warranty with standardized after-sale serivce process.
Led Ceiling Light,Ceiling Light Fixtures,Cone Ceiling Light,Ceiling And Wall Light Kits
Jiangmen Dilin Lighting High-Tech Co., Ltd. , https://www.dilinlight.com