What material is used for the lining of the intermediate frequency furnace? What are the common types?

The quality of the intermediate frequency furnace lining determines the service life, and it needs to have good refractory function and stability to be put into use better. The intermediate frequency furnace lining of different materials will react differently with the raw materials during use, so the choice of materials depends on Use to judge, let Xiaobian answer for you what material is used for the lining of the intermediate frequency furnace.

1. Varieties of lining materials for intermediate frequency furnaces

1, acid lining

Acid furnace lining is mainly quartz sand, which is low in price, widely distributed, good in insulation, low in construction requirements, less in use, and relatively stable in production, but quartz sand has low refractoriness, which cannot meet the requirements for casting large-scale intermediate frequency furnaces. During the heating process, there are two phase changes, the dimensional stability is poor, the chemical stability is not ideal, and it is easy to react with slag to form corrosion, which is the main reason for affecting the service life of the intermediate frequency furnace lining. In order to prevent these defects, fused silica can be used. 2 When the content of silicon oxide is more than 99%, the refractoriness is obviously improved, close to the melting point, and there is no secondary phase transition and no change in the heating scale during heating, and the thermal shock stability is also greatly improved.

2, Neutral furnace lining

The fused corundum is used as the lining of the intermediate frequency furnace. Because the melting point of white corundum is as high as 2050 degrees Celsius, the hardness is as high as 8, the wear resistance, high temperature resistance, and chemical stability are better than quartz. It is suitable for high temperature cast steel or large furnace lining. Due to the defects of phase transformation and large thermal expansion coefficient, the addition of spinel powder in practice can significantly improve the corrosion resistance and dimensional stability.

3, basic furnace lining

The traditional basic furnace lining is formed by dry ramming with magnesia. The use of white corundum powder or spinel powder can significantly improve the service life.

5, New material furnace lining

①Adding ultrafine powder (mostly in a few microns) in the traditional furnace lining material can improve the corrosion resistance and thermal shock stability of the furnace lining material, such as silicon powder, alumina powder, white corundum powder, spinel powder, etc.

②The traditional furnace lining is made of dry powder dry ramming molding. The defect is that it is easy to be chromatographed and form voids and other defects. In the semi-dry method, 2% and 3% water mixture is added to reduce the chromatography, and the integrity is good, and it will not form too large. Damage, just a little longer in the low temperature oven.

③ Add pure calcium aluminate cement, use pure acid or neutral lining, and add magnesium oxide, sodium 6-metaphosphate, etc. in alkaline lining.