What are the heating steps and precautions for the glass tempering furnace?

A glass tempering furnace is a specialized equipment used to heat treat glass, enhance its hardness and strength. The correct heating steps and precautions during the operation of the glass tempering furnace are the key to ensuring good tempering effect of the glass inside the furnace. Let's briefly introduce the heating steps and precautions during the heating process of the glass tempering furnace.

1. Heating steps for glass tempering furnace

1.1. Preheating stage

Before heating up the glass tempering furnace, preheating is necessary. The purpose of preheating is to achieve a relatively stable temperature for the furnace and glass, reduce temperature gradients and thermal stress. The preheating temperature is usually 150-200 degrees Celsius and can be adjusted according to specific glass and process requirements.

1.2. Heating stage

After the preheating is completed, start the heating phase. The heating process should be carried out at an appropriate heating rate to avoid thermal stress and deformation caused by excessive heating. Usually, a heating rate between 50-150 degrees Celsius per hour is appropriate, and the specific rate should be determined based on the thickness and material of the glass.

1.3. Insulation stage

Once the tempering temperature is reached, it is necessary to maintain a certain insulation time to ensure that the glass reaches the required temperature uniformly. The length of insulation time depends on the thickness and material of the glass, usually between a few minutes to several tens of minutes.

1.4. Rapid cooling stage

After the insulation is completed, it is necessary to quickly cool the glass to room temperature. This can be achieved through methods such as air cooling or water spray cooling. Cooling rate is one of the important factors affecting the tempering effect, and the appropriate cooling rate should be selected based on the thickness and requirements of the glass.

2. Precautions for heating up the glass tempering furnace

2.1. Temperature uniformity and control accuracy

During the heating process, ensuring a uniform distribution of temperature inside the furnace is crucial for the toughening effect of glass. Heating elements and temperature control systems should be adjusted to ensure the uniformity of temperature inside the furnace.

The temperature control accuracy of the glass tempering furnace is crucial for the stability and consistency of the tempering effect. It should be ensured that the temperature control system is accurate and reliable, and can maintain minimal temperature fluctuations within the preset range.

2.2. Cooling medium selection

The cooling rate of glass will affect the tempering effect, and different cooling media will produce different cooling rates. Select appropriate cooling media according to the requirements of the glass to achieve the desired tempering effect.

2.3. Check the glass surface

Before heating up, the glass surface should be carefully inspected for defects such as scratches, stains, cracks, etc. These defects may expand during heating and cooling processes, affecting the tempering effect.

2.4. Avoid temperature shocks

During the heating and cooling process, sudden temperature changes should be avoided to avoid causing thermal stress and cracking of the glass. The temperature change should transition smoothly, especially around the tempering temperature, and more caution should be exercised.

Accurate heating steps and following precautions during the glass tempering furnace can help ensure the stability and consistency of the tempering effect. During the operation, special attention should be paid to factors such as temperature uniformity, temperature control accuracy, selection of cooling medium, inspection of glass surface, and avoidance of temperature shock to ensure the quality and reliability of glass tempering.