How to solve the problem of poor flatness of tempered glass- Hangzhou Jinghu Glass Co., Ltd.

The problems of poor flatness of tempered glass can be divided into two categories:

Category 1, the problem of poor flatness of curved tempered glass. For such problems, the index of fit is usually considered. When the fit of the finished curved tempered glass fails to meet the design requirements, the following three phenomena will occur:

(1) The finished glass is twisted and deviated from the design requirements. This means that the glass that needs to be bent and tempered is not placed correctly on the roller table, and the center line of glass bending is not parallel to the roller table. If this happens, the operator needs to re-adjust the position of the glass on the loading table to make the glass The center line of the bend is parallel to the roller table.

(2) The finished glass is different from the design bending depth. This shows that there is a problem with the setting of the tempering process parameters: in the heating stage, the heating temperature of the glass is not enough; in the cooling stage, the main reason is that the upper and lower air outlets of the air grille are not synchronized when blowing. . If the lower air outlet is opened for blowing first, the bending depth of the glass after forming will increase. On the contrary, if the upper air outlet is opened first to blow air, the bending depth of the glass after forming will be reduced, and the arc will not be formed according to the design depth. At this time, the operator can re-adjust the process parameters and appropriately adjust the bending depth of the glass.

(3) The profile quality of the finished glass does not meet the design requirements.

The operator can appropriately adjust the bending time and quenching time of the heating section, or the tension of the transmission chain of the bending section, and solve such problems by adjusting the tempering process parameters or equipment.

The second category is the problem of poor flatness of flat tempered glass. There are five main types of such problems:

(1) Glass deformation caused by the temperature difference between the upper and lower surfaces of the glass when heated

①The tempered glass plate is bent upwards. This phenomenon is due to 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. The glass that maintains this temperature state enters the cooling chamber for cooling. During the cooling process, when the upper and lower surfaces of the glass are cooled When the cooling temperature and wind pressure and other conditions are the same, due to the high temperature of the upper surface of the glass, the shrinkage of the upper surface is greater than that of the lower surface after cooling, and the phenomenon of upward bending and deformation of the glass plate will occur. In this case, the temperature at the bottom of the heating furnace can be increased to minimize the temperature difference between the upper and lower surfaces of the glass.

②The tempered glass plate is bent downwards. This phenomenon is due to 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. The glass that maintains this temperature state enters the cooling chamber for cooling. During the cooling process, when the upper and lower surfaces of the glass are cooled When the cooling temperature and wind pressure are the same, due to the high temperature of the lower surface of the glass, the shrinkage of the lower surface is greater than that of the upper surface after cooling, and the phenomenon of downward bending of the glass plate will occur. In this case, the temperature at the bottom of the heating furnace can be lowered to minimize the temperature difference between the upper and lower surfaces of the glass.

(2) The glass is deformed due to the temperature difference between the middle and the edge when the glass is heated

After the glass is heated in the heating furnace, if the temperature of the middle part is higher than the temperature of the edge part, then during the cooling process, the shrinkage of the middle part with the higher temperature on the glass will be greater than that of the edge part with the lower temperature. When the glass is cooled to room temperature, the size of the edge of the glass will be larger than the size of the middle part, and a large compressive stress will be formed on the edge of the glass, so that the glass plate will bend and deform downwards.

Similarly, after the glass is heated in the heating furnace, if the temperature of its edge is higher than the temperature of the middle part, then during the cooling process, the shrinkage of the higher temperature middle part on the glass will be greater than that of the lower temperature edge part. The amount of shrinkage, when the glass is cooled to room temperature, the size of the middle part of the glass will be larger than the size of the edge, forming a large tensile stress on the edge of the glass, resulting in the phenomenon that the glass plate is bent and deformed upwards.

Hangzhou Jinghu Glass Co., Ltd. is one of the most significant glass and mirror manufacturer in China with more than 15 years of experience with a factory covering a space of 12,000sqm. Since its founding, Jinghu glass has been constantly upgrading its factories to be a comprehensive factory that meets world-class standards in producing processed glass and mirror, finished mirror integrating design, research, production, marketing and after-sales services. As Custom Furniture Toughened Glass Manufacturers and Furniture Tempered Glass Factory, We strictly control the quality in production and after production, to keep the good quality before send to customers. Full ranges of glass and mirror products to meet your one-stop purchasing requirements.