Causes of pressure spots on the surface of color coated rolls

Painted rolls are now very popular with everyone, but now it is showing a trend of divergence. The color coated steel coil market in the northern region has been steadily sorted out, and the demand is still not large. Therefore, the price of color coated rolls is relatively weak. The important factor affecting the price trend of color coated rolls is the price of raw materials.
Compared with building boards, the substrates used for color coated boards for home appliances have higher elongation, yield ratio and corresponding r value and n value; moreover, they require strong adhesion between the paint film and the substrate, coating Has a certain flexibility, the corresponding hardness is lower. When the color coated steel coil for household appliances is cut and uncoiled, a defect often occurs on the surface-the surface pressure spot defect, the defect is the coating of the color coated board when it is baked and cooled after cooling, due to the winding tension. The surface is slightly deformed, and sometimes the surface is rough, showing a visually visible pressure spot shape. The slight plaque defects will gradually disappear with the extension of the storage time of the steel plate, and can also be eliminated after heating. However, the more serious plaque defects cannot be eliminated even if the above measures are adopted, thereby affecting the user's use.
Spot is a kind of defect produced in the production process. If you are looking for the cause and influencing factors of this kind of defect in the production process, you need to go through multiple shutdowns to check and affect the production plan and increase the production cost. Therefore, it is necessary to simulate and copy this kind of defect through the laboratory and evaluate it to find the cause of the defect and the factors that affect the defect from all aspects.
Because the color coated coils are based on steel, they have an important relationship with the price of the national steel market. We are mainly stable. As of now, the average price of the national steel market is the same as the price of the previous week. Yes, and the price of Shandong's steel market is also a stable phenomenon for color coated coils. The volume of color coated coils is still relatively large, and merchants' mentality is now more cautious. However, judging from the current price situation, most people are concerned about the continuity of the price of color coated rolls. The degree of digestion of steel stocks in the near future will be the key to affecting the price trend of color coated coils