What Is A Glass Tempering Furnace? What Are The Cooling Methods for Glass Tempering Furnaces?

Nowadays, glass tempering furnaces are widely used. Generally, glass tempering furnaces work non-stop 24 hours a day, but it is inevitable to repair and maintain them. In these cases, the glass tempering furnace needs to be shut down for maintenance. However, before doing these tasks, it is necessary to cool down the glass tempering furnace. So what is a glass tempering furnace? What are the cooling methods for glass tempering furnaces?

1. What is a glass tempering furnace

Glass tempering furnace is an equipment that produces tempered glass through physical or chemical methods, which is divided into two types: physical method glass tempering furnace and chemical method glass tempering furnace. The physical method is to heat and then rapidly cool flat glass, forming compressive stress on the surface of the cooled glass and tensile stress inside the glass, thereby improving the strength of the glass and making ordinary annealed glass a protective device for glass. Because this method does not change the chemical composition of the glass, it is called a physical glass tempering furnace equipment. The chemical method is to improve the strength of glass by changing the chemical composition of the glass surface. Currently, the method used is surface dealkalization and alkali metal ion exchange. Because this method changes the chemical composition of glass, it is called a chemical method glass tempering furnace equipment.

2. Cooling method of glass tempering furnace

There are three cooling methods for glass tempering furnaces, namely: natural cooling, emergency cooling, and furnace cleaning cooling. Natural cooling is generally applicable to the normal operation of glass tempering furnaces. For some other reasons, if production needs to be stopped for a certain period of time, natural cooling will be chosen. Natural cooling takes two days, and this cooling method plays a protective role in the insulation system of glass tempering furnaces. Emergency cooling and furnace cleaning cooling achieve a cooling effect in a short period of time, without wasting production time. However, regardless of which cooling method is used, it should be operated according to the actual situation.

2.1. Natural cooling

If the glass tempering furnace is not put into use within three days, this method can be chosen.

2.1.1. Turn off the heating control switch first, turn off the heating circuit breaker, and the heating system will have no power.

2.1.2. Turn off the control and power switch of the upper, lower, and wind grid sections, leaving only the heating main drive to operate.

2.1.3. Let the temperature naturally decrease. If the temperature drops to 300 ℃, turn off the control of the main drive and the power switch.

2.1.4.When locking the electrical cabinet door, turn off the main switch.

2.2. Emergency cooling

If there is adhesion or explosion in the glass tempering furnace, this method can be chosen.

2.2.1. Turn off the heating control switch first, turn off the heating circuit breaker, and the heating system will have no power.

2.2.2. Turn off the control and power switch of the upper, lower, and wind grid sections, leaving only the heating main drive to operate.

2.2.3. Next, it is necessary to open the cone valve on the top of the furnace and two furnace doors to accelerate the convection of air inside the furnace.

2.2.4. If the temperature drops to 600 ℃, raise the furnace body by another 5 centimeters. After 30 minutes, raise the furnace body by another 5 centimeters and keep repeating this process.

2.2.5. When the temperature drops to 300 ℃, it can be raised to the top. At this time, it is necessary to attach the safety pin and prepare for the furnace cleaning work.

2.2.6. When the temperature drops to 200 ℃, the four corners inside the furnace are blown towards the furnace with a fan, causing the temperature to quickly drop to around 50 degrees. At this time, manual cleaning of some glass fragments on the ceramic rollers and lower iron plates can be done.

2.3. Cleaning and cooling the furnace

2.3.1. Turn off the heating control switch, turn off the heating circuit breaker, and the heating system will have no power supply, which will cut off the power supply of the heating system.

2.3.2. Next, proceed with the furnace flushing operation, using defective glass products for unheated tempering, and reducing the temperature inside the furnace to below 600 ℃.

2.3.3. Open the cone valve and two furnace doors on the top of the furnace to accelerate the convection of air inside the furnace.

2.3.4. If the temperature inside the furnace drops to 200 ℃, the furnace body will rise to the top.

2.3.5. If the temperature drops to 100 ℃, the four corners inside the furnace are blown towards the furnace with a fan, causing the temperature to quickly drop to around 30 degrees. At this time, manual cleaning of some glass fragments on the ceramic rollers and lower iron plates can be done.