How to improve the temperature resistance of the intermediate frequency furnace lining?

The high temperature performance of the furnace lining mainly depends on the physical, ramming material, chemical properties and mineral composition of the refractory materials used. Under the premise of the selection of raw and auxiliary materials, the sintering process is to obtain a good microstructure of the furnace lining to give full play to its high temperature resistance. The key process of the function. The degree of densification of the furnace lining sintering is related to the chemical composition of the refractory material, the particle size ratio, the sintering process and the sintering temperature.

The following editor will give you a detailed explanation from several factors affecting the temperature resistance of the intermediate frequency furnace lining, how to improve the temperature resistance of the intermediate frequency furnace lining.

1. Remove the mica paper when building the furnace.

2. The crystal quartz sand for furnace construction is treated as follows:

3, hand selection: firstly remove lumps and other impurities;

4. Magnetic separation: it is necessary to completely remove magnetic impurities;

5. Dry ramming material: it is necessary to carry out slow drying treatment, the drying temperature is 200 degrees Celsius - 300 degrees Celsius, and the temperature is kept for more than 4 hours.

6. Selection of intermediate frequency electric furnace binder: use boric anhydride (B2O3) instead of boric acid (H3BO3) as binder, and the addition amount is 1.1%-1.5%.

7. Selection and ratio of furnace building materials:

8. Selection of furnace building materials: It should be noted that not all quartz sands with SiO2 greater than or equal to 99 percent can be used as lining materials for induction furnaces. The important thing is the size of the quartz grains. , (such as crystal quartz sand SiO2 with high purity, bright white and transparent surface.) The larger the furnace capacity, the higher the requirements for crystal grains.

9. Proportion: The ratio of quartz sand for furnace lining: 6-8 mesh, 10 percent-15 percent, 10-20 mesh, 25 percent-30 percent, 20-40 mesh, 25 percent-30 percent, 270 mesh, 25 percent-30 percent.

10. Knotting of the furnace lining: The quality of the furnace lining is directly related to the quality of sintering. When the lining is knotted, the particle size distribution of the sand is uniform and will not segregate. It is beneficial to improve the service life of the induction furnace lining.

11. Knotted furnace bottom: the thickness of the furnace bottom is about 280mm, and the sand is filled in 4 times. When manually knotting, avoid uneven density everywhere, and the furnace lining after baking and sintering is not dense. Therefore, it is necessary to strictly control the feeding thickness. The thickness of sand filling is not more than 100mm\/time, the furnace wall is controlled within 60mm, multiple people are divided into shifts, 4-6 people per shift, 30 minutes each time the knot is replaced, and the furnace is rotated slowly around the furnace. Uneven density is formed.

12. Complete sintering stage: When sintering at high temperature, the sintering structure of the intermediate frequency electric furnace crucible is the basis for improving its service life. The sintering temperature is different, the thickness of the sintered layer is insufficient, and the service life is significantly reduced.