Adhesion, at the same time can remove nitrogen, sulfur other impurities in steel, in addition, it must also react with silicon dioxide on the surface of silicon steel to form an excellent magnesium silicate insulating bottom layer. Therefore, the coating quality of magnesium oxide coating liquid on the surface of oriented silicon steel plays a vital role in the quality of silicon steel products.

The role of magnesium oxide in silicon steel its use

Magnesium oxide acts as a coating during decarburization annealing of silicon steel. Before high temperature annealing. One is to prevent bonding during high-temperature annealing, the other is to form magnesium silicate with the oxide layer during high-temperature annealing to improve magnetic induction. Magnesium oxide mainly acts as a separator to prevent the strip sticking during the high temperature annealing stage, at the same time it can remove impurities such as nitrogen sulfur in the steel. In addition, it also reacts with silicon dioxide on the surface of silicon steel to form an excellent magnesium silicate insulating bottom layer . Therefore, the coating quality of magnesium oxide coating liquid on the surface of oriented silicon steel plays a vital role in the quality of silicon steel products.

Currently, the magnesium oxide coating liquid is applied by a two-roll coating machine. The two-roller coating machine includes an upper coating roller, a lower coating roller, a tray, a magnesium oxide coating liquid circulation device, a nozzle for spraying the magnesium oxide coating liquid in the magnesium oxide coating liquid circulation device to the upper surface of the strip The lower coating roller is immersed in the tray, the nozzle sprays the magnesium oxide coating solution sprayed onto the upper surface of the strip steel, overflows into the tray. The lower coating roller uses the magnesium oxide coating solution in the tray to perform the lower surface of the strip steel; Of coating.

However, due to the magnesium oxide solution in the coating recycling process, the magnesium oxide solution in the tray does flow smoothly, magnesium oxide reacts with water to form magnesium hydroxide precipitate, magnesium hydroxide combines with carbon dioxide in the air to form a precipitate Magnesium carbonate. Magnesium carbonate magnesium hydroxide have poor fluidity are prone to agglomeration deposition. Therefore, the fluidity of the coating liquid in the tray is high. Over time, the coating liquid is prone to build up scale, resulting in poor coating quality of the lower coating roller. Double lines, wear the lower coating roller, directly causing product quality defects. In severe cases, it is necessary to stop the machine to replace the coating roller, clean up the circulation pipe blockage, deal with the scaling of the tray, etc.

These unfavorable factors on the one hand greatly increase the labor intensity of employees, on the other hand interfere with the continuous production on site, which directly affects the production efficiency. At the same time, because the cured magnesium oxide coating liquid is stuck in the tray cannot be used, only is it difficult to clean , But also cause waste of magnesium oxide. In addition, the liquid thrown off the edge of the coating roller affects the coating quality, at the same time interferes with the operation of the coating machine, causing scale deposits on the edge of the coating roller uneven coating of the strip edge.