[China Glass Net] (1) Glass deformation caused by temperature difference between the upper and lower surfaces of the glass during heating 1 The tempered glass elevator board is bent upwards. This phenomenon is caused by the fact that after the glass is heated in the heating furnace, the temperature of the upper surface of the glass is higher than the temperature of the lower surface, and the glass which maintains the temperature is cooled into the cooling chamber, and during the cooling process, when the upper and lower surfaces of the glass are cooled. When the cooling temperature and the wind pressure are the same, since the upper surface temperature of the glass is high, the amount of shrinkage of the upper surface after cooling is larger than that of the lower surface, and the glass sheet is bent upward and deformed. In this case, the temperature at the bottom of the furnace can be increased to minimize the temperature difference between the upper and lower surfaces of the glass. 2 The tempered glass plate is bent downward. This phenomenon is caused by the fact that after the glass is heated in the heating furnace, the temperature of the lower surface of the glass is higher than the temperature of the upper surface, and the glass maintaining the temperature enters the cooling chamber for cooling, and during the cooling process, when the upper and lower surfaces of the glass are cooled. When the cooling temperature and the wind pressure are the same, the glass will appear on the lower surface due to the higher temperature of the lower surface of the glass. (2) Glass deformation caused by temperature difference between the middle and the side of the glass during heating After the glass is heated in the heating furnace, if the temperature of the middle part is higher than the temperature of the edge, the shrinkage of the middle part of the glass with higher temperature during the cooling process will be greater than the shrinkage of the lower temperature part. When the glass is cooled to room temperature, the edge size of the glass is larger than the size of the intermediate portion, and a large compressive stress is formed at the edge of the glass, so that the glass plate is bent downward and deformed. Similarly, after the glass is heated in the heating furnace, if the temperature of the side portion is higher than the temperature of the intermediate portion, the amount of shrinkage in the middle portion of the glass having a higher temperature during the cooling process will be greater than that of the lower temperature portion. The amount of shrinkage, when the glass is cooled to room temperature, the size of the middle portion of the glass is larger than the size of the side portion, and a large tensile stress is formed at the edge of the glass, so that the glass sheet is bent upward and deformed. Waffle Jersey Fabric,Polyester Jersey,Cotton Waffle Fabric,Plain Spun Polyester Fabric Zhejiang Tangber Trade Co .,Ltd , https://www.tangber.com