The lower half of the draw roller of the roller coater is immersed in the paint tank, so in order to continuously coat the strip, the PPGL coil paint must be continuously replenished to ensure the contact between the paint and the draw roller and the sinking of the draw roller in the paint. Depth. The paint supply system generally does this.
The paint of PPGL coil is usually sent to the trough by a pump. In order to maintain the uniformity of the coating applied to the strip, there is a reciprocating pipeline between the trough and the paint bucket to realize the continuous circulation of the paint. For fire and explosion safety, pneumatic motors and pneumatic pumps are used to stir in paint storage tanks and convey paint. Sometimes, considering the convenience of changing the paint and cleaning, hoses are directly connected to the paint storage tank and the material through the roller coater instead of using a fixed piping system. Under normal circumstances, the first coat (primer) or the back coat is replaced less frequently, and sometimes even if it is replaced, it does not require a thorough cleaning. The paint color and variety of the front surface paint are changed more frequently, so it is necessary to clean the coating head, paint tank, pipeline, and other parts in contact with the paint. Generally, it takes 0.5 to 1 hour to clean. This pair of high-speed production unit coating head roll coaters, when the coating or rubber roller needs to be replaced, make the cleaned and spare coating head enter the working state and let the coating head (including the material tray) be replaced out of work condition, clean as required. In this way, cleaning can be performed without stopping the machine, thereby greatly improving the working efficiency of the unit. In the case of a single-coating head, it is often necessary to replace the cleaned rollers and other components as soon as possible, start the engine unit, and then thoroughly clean the replaced components. From the point of view of safety and the use of production sites, only a small amount of paint supplied to the roller coater should be placed next to the roller coater for backup. The paint supply of the workshop is guaranteed by the paint configuration room and the paint warehouse. The paint preparation room is generally connected to the production workshop. The paint is specially formulated according to the requirements of the production plan and production process so that the variety, color, and viscosity meet the production requirements. The paint is stirred evenly, stored at the specified temperature, and supplied to the unit from time to time—required paint.
The storage of large quantities of paints and organic solvents requires specialized warehouses. From a safety point of view, the paint warehouse must be far from the production workshop. Still, at the same time, it is also necessary to consider the convenience of supplying paint to the workshop, which is generally located 100m away from the workshop and the fire source. When storing paint, it is necessary to know the storage period of the paint, as polyester, polyacrylic, and fluororesin paints can be stored for about one year. Polyvinyl chloride (PVC) organosol or plastisol can be stored for about 6 months. At the same time, according to the production law and the distance and production cycle of the coating production plant, enough reserves should be reserved. Also, pay attention to the variety and color.