Commonly used refractory materials are mainly the following:
1.Refractory bricks or wire bricks
High alumina bricks: have excellent refractoriness, high temperature strength and chemical stability. They can withstand the high temperature environment in the heating furnace and are suitable for high temperature areas of the furnace, such as the furnace wall and furnace roof.
Mullite bricks: Mullite is the main crystal phase, with good thermal stability and strong thermal shock resistance. They can be used in key areas of the heating furnace, such as near the furnace door and the nozzle, and can withstand frequent temperature changes without breaking easily.
2.Refractory fiber materials
Aluminum silicate fiber blanket: It has the characteristics of low thermal conductivity, light weight and softness. It can be used as the insulation material of the continuous annealing furnace and laid on the furnace wall and furnace roof to effectively reduce heat loss and improve energy efficiency.
3.Unshaped refractory materials
Refractory castables: used in some special parts of heating furnaces, such as around the burner or burner, furnace bottom, etc., and can adapt to complex shapes and working conditions.
Refractory plastics: have a certain plasticity and can be rammed on site. It can be used to repair the damaged parts of the heating furnace, or in some places where it is difficult to use shaped refractory materials.
When choosing refractory materials for heating furnaces, the following factors need to be considered:
Working temperature: select materials with appropriate refractoriness according to the maximum working temperature of the heating furnace.
Atmosphere environment: consider whether the atmosphere in the furnace is corrosive, and select refractory materials with good chemical corrosion resistance.
Mechanical strength: Refractory materials should have sufficient strength to withstand the pressure of materials in the furnace and their own weight.
Thermal stability: can withstand frequent changes in temperature, not easy to crack or peel off.
Construction and maintenance convenience: select refractory materials that are easy to construct and repair to reduce costs and downtime.
