TangShan color coated board teaches you how to prevent some of the methods that affect the appearance of products in production, remove black spots and make our products more beautiful.
Black spot is a kind of defect which is difficult to find or can not be found in production, and it will affect the subsequent surface quality. Research on black spot defect has a positive effect on product quality improvement. There are three types of
typical black spots, as follows:
1. The first black spot defect
The black spot defects are mostly distributed at 1/4 or 3/4 of the width direction of the steel band and strip distribution along the rolling direction of the steel strip. After
uncoiling, black spots appear periodically, but the period decreases gradually from outer ring to inner ring, and corresponds to the diameter of uncoiling coil. Finally, galvanized coils are uncoiled to a certain position, and black spots disappear.
2. The Second Black Spot Defect
This kind of black spot defect is not found after uncoiling, but after deep processing (cold drawing, roll pressing), it is found that most of the parts are distributed on the machined surface.
3. The Third
Black Spot Defect
The black spot defects are mostly distributed at the edge of the width direction of the steel band, and the pass band exists, which distributes in droplet disorder along the rolling direction of the steel band. At the same time,
friction marks are found on the plate surface.
The prevention measures for black spot are as follows:
1. Standardize the protective conditions for transportation and loading to avoid local abnormal extrusion and friction.
the passivation process and determine the appropriate film thickness. Especially when there are stamping and drawing requirements for customers'products, it is necessary to determine the corresponding film thickness and optimize the corresponding process.
3. Protect the passivator against splash, and avoid the passivation liquid falling on the strip when it is not put into operation.
Knowing this, we can produce better and more perfect products.
Our company specializes in the production
of color coated panels, which is the most beautiful companion for your choice of color coated panels.