Fire resistant glass is a special glass with certain fire resistance after tempered by a special method. The strength and hardness of fireproof glass are inseparable from the tempering process, and good tempering technology and process is the premise of producing high quality fire resistant glass. The smoothness, finish and evenness of glass are closely related to the heating temperature of glass. How to control the evenness of glass heating temperature is very important, which can be analyzed from the following aspects:
1. Select the appropriate heating temperature according to the actual situation.
There are three main heating ways of fire resistant glass in toughening furnace: conduction, radiation and convection. Under normal working conditions, in the heating area of the central heating element, if the heat consumption of a region in the electric furnace exceeds the heat generated by the electric furnace, the temperature of this region will begin to drop and overload phenomenon will occur. The success of glass tempering is mainly determined by the low temperature of the glass plate. Once the overload phenomenon occurs in the electric furnace, it is easy to cause the glass to break when cooling in the cooling section.
2. Reasonable control of heating time.
The power generated in the heating process of the electric furnace is certain, and the hot pendulum movement of the glass should be carried out continuously in the heating furnace in order to make all parts of the glass uniformly heated.
3. The method of glass placement should be studied.
In order to achieve uniform heating of glass in electric furnace, the placing method of glass on the tabletop is also very important. Reasonable arrangement of glass and uniform control of the time interval of placing glass in each furnace is beneficial to ensure the uniformity of longitudinal and transverse load in electric furnace.
4. The cooling time speed should be fast.
The cooling speed of glass mainly depends on the thickness and other performance. Try to use the ideal cut-off dry cold air to cool at a faster speed to ensure the balance of the positive and negative sides of the fire resistant glass cooling. There will be a cold swing movement in the cooling section to ensure that the glass fragments are uniform. There can be no scratches, deformation, bubbles and other phenomena in the process of glass tempering, otherwise the production is unqualified products.