How are industrial coating supplies produced?

The production process of industrial coatings mainly includes the following key steps: raw material preparation, mixing and stirring, grinding and dispersing, color matching, filtering, and packaging and storage.
raw material preparation
The main raw materials for industrial coatings include resins, solvents, pigments, and additives. Resin is usually made of epoxy, polyurethane or acrylic, while solvents include xylene, butyl ester, etc. The selection and ratio of pigments and additives are determined according to the specific needs of the product.
Mixing and stirring
The mixing process is carried out in a closed mixing tank. Firstly, pour the resin and some solvent into the tank, start the stirring blade to rotate at low speed, and control the temperature at 30-40 ℃ to prevent solvent evaporation. After stirring for 15 minutes, add powders such as titanium dioxide and calcium carbonate in batches. The feeding speed of the powders should be slow to avoid dust. The mixing time usually lasts for 40-60 minutes, and the tank pressure needs to be monitored in real time. If it exceeds 0.3MPa, the machine should be stopped immediately for inspection.
Grinding and dispersing
Grinding and dispersion are carried out using a sand mill or a three roll machine. The mixed slurry enters the grinding chamber, and zirconia beads collide with the material particles at high speed, with a particle size of less than 20 microns. Every 30 minutes of grinding, samples are taken to test the fineness. When the scraper fineness meter displays a stable value of 15 μ m, it meets the standard. When the grinding temperature is too high, the cooling water circulation system should be turned on to avoid resin sticking due to high temperature. Grinding media must be screened and replaced monthly, and if the wear rate exceeds 5%, it must be scrapped.
toning
The color mixing room is equipped with a standard light source box and a colorimeter. Pour the basic white paint into the color mixing tank and add color paste according to the color card number. For dark colors, add main colors such as iron red and carbon black first, and for light colors, add titanium blue and lemon yellow first. Add the color paste in three parts, stir for 10 minutes each time, and compare the color chart. If the Δ E value is less than 1.0, it is considered qualified. If the color difference is too large, adjust it with a diluent. The color mixing tank is thoroughly cleaned every week to prevent residual color paste from contaminating new batches.
Filtering and packaging storage
The filtering process adopts a dual guarantee of bag filter and vibrating screen. The coating is filtered by a 200 mesh filter bag to remove impurities, and the vibrating screen has a pore size of 80-100 mesh. The filtration pressure should not exceed 0.25MPa. If the flow rate is too fast, it will reduce the filtration accuracy. The filtered coating is placed in a temporary storage tank for defoaming, and the defoaming time is not less than 2 hours. The packaging area is divided into channels for dangerous goods and ordinary goods. Before packaging in iron drums, nitrogen is used to replace the air, with a filling volume error of ± 0.5 kilograms. The finished product warehouse should be kept ventilated and dry. The storage temperature for epoxy coatings should not exceed 35 ℃, and water-based coatings should prevent freeze-thaw cycles.