The three-roller and six-arm are composed of submerged rollers, stabilizing rollers and support arms. They are an important part of the zinc pot and are widely used in galvanizing lines.
 
As we all know, the scratch of the sunken roll is very harmful to our hot-dip galvanizing production enterprises. Sink roll scratches are a type of surface defect in the production of continuous hot-dip galvanized coils. It not only directly affects the appearance of hot-dip galvanized products, but also affects the performance of hot-dip galvanized products. Corrosion resistance makes the product corrode first at the scratched place during use or transportation, thereby losing the characteristics that the hot-dip galvanized product should have; in addition, the hot-dip galvanized sheet with scratches by the sinking roller cannot be used as the production substrate of the color-coated sheet.
 
Therefore, we must be clear about the mechanism of Sink roller scratches, so that we can take effective measures to prevent and control the occurrence of Sink roller scratch defects. So what is a sink roller scratch? How did it come about? The common sinking roll scratch is that the strip steel and the sinking roll are in mutual movement, the speed of the two is inconsistent, and relative sliding occurs, and the strip surface is scratched by the sinking roll surface. Specifically, the strip steel enters the zinc pot from the nose of the annealing furnace for hot-dip galvanizing, and is turned to the zinc pot through the submerged roller. Since the submerged roller is in a special position in the zinc liquid, it is not conducive to the installation of the motor for transmission. Therefore, most of the submerged rolls are passive rolls, which completely rely on the friction between the surface of the strip and the surface of the submerged roll to make the submerged roll and the strip move at the same speed; but sometimes due to mechanical equipment, production process control, the use of submerged rolls, etc. Due to the influence of various factors, the transmission friction between the strip and the sinking roll is insufficient, and the strip and the sinking roll slip relative to each other, so the surface defect of the sinking roll of the hot-dip galvanized product is produced.
 
Then, in terms of equipment, Qingdao Hexin Machinery Co., Ltd. reminds us that we should pay attention to the following points to avoid scratch defects:
1. The mechanical structure of the Sink roller device. From the point of view of increasing friction, the roll surface of the sunken roll should have a certain type of groove;
2. Requirements for the material of the roller surface. Due to the special position of the sunken roll, the material of the roll surface of the sunken roll should meet the corrosion resistance, and have certain hardness and roughness requirements;
3. The sinking roller has a reasonable dead weight.
4. Solve the problem of axial fixation of the Sink roller.