The fault of the corrugated steel sheet

1. Scratch caused by zinc pot roll（corrugated steel sheet)
The scratch caused by zinc pot roll is an important reason for the scratch of galvanized products, which accounts for most of the scratch problems. Generally, the zinc pot roll is mainly composed of sinking roll, correction roll and stabilizing roll. It is in a special position in the zinc liquid, which is not conducive to setting the motor to realize the transmission. For this, many zinc pot rolls are passive rolls, which mainly use the friction between the steel surface and the rod surface of the zinc pot roll to realize the same speed rotation of the zinc pot roll and the strip steel. However, due to the change of the composition of liquid zinc and the influence of relevant factors such as the application of zinc pot roll, the relative sliding between strip steel and submerged roll occurs due to insufficient transmission friction, which leads to the scratch problem of zinc pot roll.

2. Air knife streak problem(corrugated steel sheet)

If the air knife nozzle is partially blocked, strip marks will be generated after the zinc layer at the corresponding position of the strip steel. The strip marks are generally caused by the sudden change of the pressure of the air knife when the speed of the production line changes greatly, resulting in the splashing of liquid zinc, which blocks the air knife, or the distance between the air knife and the strip steel is relatively small, and the bending of incoming materials, uneven heating of the strip steel and too small tension of the strip steel will lead to the blockage of the strip steel scraper knife, resulting in strip marks. In this regard, the staff should effectively control the range during the lifting process of the production line and pay attention to the shape of the incoming material. If the shape is relatively poor, the air knife spacing should be adjusted in time, and the tension and stabilizing roll should be adjusted reasonably to ensure that the strip steel can obtain a relatively good flatness in the middle of the air knife nozzle, Avoid blocking the air scraper of strip steel. In case of gas knife streaks, the gas knife shall be opened quickly at the weld and cleaned with professional equipment.(corrugated steel sheet）