Usage and precautions for using corundum tubes

Corundum tube Suitable for various laboratory metal and non-metal sample analysis and melting materials. Corundum tube Mainly used for high-temperature vacuum furnaces, vacuum atmosphere furnaces, tin bath tubes for float glass industry, protective tubes for solar glass, electric furnace wire support tubes, muffle furnace tubes for aluminum trichloride industry, etc. The product has the characteristics of operating temperature of 1200-1800 degrees, high density, good thermal shock resistance, acid and alkali resistance, corrosion resistance, and long service life, and is highly praised by universities, colleges, the electric furnace industry, and users. According to customer feedback, the service life of vacuum tubes can reach 60 times within 1800℃, and the service life of tin bath tubes can reach 6 years.

Product characteristics:

1.High purity: Al2O3＞99%, good chemical corrosion resistance

2.Good temperature resistance, long-term use at 1600℃, short-term use at 1800℃

3.Good rapid cooling and heating performance, not easy to burst.

4.Grouting to form high-density pure alumina crucibles.

Corundum tube Usage and precautions

1. Corundum tube It is a very important component in tube furnaces. Because it is made of corundum material, its ability to withstand rapid cooling and heating is very poor, and its service life is very limited. Generally, it is recommended that the temperature rise and fall be kept below 5℃/minute, and it should be slow. During the cooling process, the cooling curve must be set, and it is not allowed to directly cool naturally from high temperature to room temperature, which will easily cause the tube to crack. The temperature at which the tube is easily cracked is generally 800-1000℃.

2.New Corundum tube or corundum that has not been used for a long time needs to be baked at 200-300 degrees for 5-6 hours to Corundum tube remove the moisture, which helps to extend the service life of the corundum tube, and moisture is an important reason for the fracture of the corundum tube. For samples burned in a tube furnace, especially those burned to around 1300℃, it is best to have a low water content (adsorbed water, crystalline water, water that may be produced during heating, etc.), and it is recommended to pre-burn the samples before putting them into the tube furnace.

3.Keep the furnace tube clean and hygienic, and no substances that react with Al2O3 should remain in the furnace tube. When burning materials, in order to extend the service life of the furnace tube, do not place the materials directly on the furnace tube, but place them in a boat-shaped crucible.

4.When heating, be sure to put alumina insulation plugs in the furnace tube, 2 on one side, a total of 4, located between the hot zone and the cold zone. If the plugs are not placed, the temperature at both ends of the furnace tube will be higher, and the O-rings in the flange cannot withstand the higher temperature, resulting in poor airtightness. Placing the plugs at both ends of the furnace tube helps to form a balanced temperature field.

5.Suggest Corundum tube the flanges at both ends are supported by a support frame, so that Corundum tube it is not subjected to force in the vertical direction, Corundum tube it will not bend or break under stress at high temperatures.

6.If the furnace needs to be used continuously, the temperature of the furnace can only be reduced to around 200℃, and it cannot be reduced to room temperature, which is beneficial to the service life of the furnace tube.

7 .Corundum tube The temperature resistance of the corundum tube is related to its purity. The higher the purity, the higher the temperature resistance, but the worse its ability to withstand rapid cooling and heating.

8. Corundum tube The large temperature difference between the inside and outside of the tube furnace and the excessive compressive stress on the screws at both ends together cause easy breakage. One solution is to wrap the part of the corundum tube exposed to the air with insulation material. Of course, asbestos is the cheapest. Although it is not recommended, there is no way, other insulation materials are too expensive.

9.Do not forcefully touch the corundum furnace tube, nor touch the high-temperature furnace tube with low-temperature objects. It is best not to sample or add samples at high temperatures, as this can easily damage the corundum furnace tube.