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What is insulating fire brick?

Views: 15     Author: Site Editor     Publish Time: 2020-05-22      Origin: Site

From the point of view of development and growth rate, China's refractory industry has farewell to the period of rapid development, and the development mode is transiting to the stage of industrial transformation and upgrading. In the past, purely pursuing the extensive growth of production capacity has no longer adapted to the development trend of the market. At present, the refractory industry is facing a serious imbalance between supply and demand, showing a situation of oversupply. Therefore, the emergence of refractory bricks has greatly alleviated this situation. So, I don't know what you know about firebricks? Here we briefly introduce insulating refractory bricks and related knowledge. Hope to help you better understand insulating refractory bricks.


The analysis points are as follows:

♦ What is insulated fire brick

♦ Classification of insulated refractory bricks

♦ Method of selecting insulated fire bricks

♦ Conclusion


What is insulated fire brick

Refractory brick is mainly designed for high temperature resistance, is a refractory material, often used in lining furnace, kiln, fire box and fireplace. Refractory bricks usually contain 30-40% aluminium oxide, and the main raw materials are usually used together with other materials. With the increase of alumina content, the kiln bricks with alumina content of 80% or higher can be obtained. Insulated refractory bricks are one of them. The fireproof brick has low thermal conductivity and low thermal storage. They can be used as hot surfaces or as backing insulation for compact bricks. The range of insulating fireproof bricks ranges from grade 23 to grade 32.Now it is widely used in flue heat preservation, hot blast stove and kiln spare heat insulation materials.


Classification of insulated refractory bricks

Thermal insulation refractory bricks include the following categories:


(1) High alumina heat-insulating lightweight refractory bricks

High alumina heat insulating lightweight refractory bricks can be used to lay insulation layer and components without strong erosion and erosion to high temperature melting materials. When in direct contact with flame, the surface contact temperature of high alumina insulating refractory bricks should not be higher than 1350 C. Mullite thermal insulation refractory brick can directly contact the flame, which has the characteristics of high temperature resistance, high strength and remarkable energy saving effect. It is suitable for lining of pyrolysis furnace, hot blast furnace, ceramic roller kiln, electric ceramic drawer and various resistance furnaces.


(2) Clay insulated lightweight refractory bricks

It is an insulating refractory brick made from refractory clay with a content of 30%~48%. The combustion plus character method and foam method are used in the production process. The product is made of refractory clay, drift beads and refractory clay clinker, adhesives and sawdust, ingredients, mixing, shaping, drying and firing.


(3) Diatom insulated lightweight refractory bricks.

It is a heat-insulating refractory product made of diatomite as the main raw material. It is mainly used for insulating layer below 900 DuC.


(4) Floating-bead Bricks

It is a heat insulation and refractory product made of drifting beads as the main raw material. Floating beads are hollow beads of aluminosilicate glass floating from fly ash of thermal power plants. It has light body, thin wall, hollow, smooth surface, high temperature resistance and good thermal insulation. With these excellent properties of floating beads, lightweight and high quality thermal insulation refractories with excellent thermal insulation properties can be produced. Semi-dry process can be used to produce float bricks.


Method of selecting insulated fire bricks

(1) After taking thermal insulation measures, the thermal equipment shall not affect the service life of the whole refractory brick;


(2) For continuous high temperature kilns, large area insulation is generally reasonable, which can reduce heat loss. However, for some special parts, such as the top of open hearth, when the insulation measures affect the service life of the top, it is not suitable for insulation. For regular kilns, heat storage loss is the main factor of heat loss. If the heat loss caused by the increase of masonry temperature caused by thermal insulation exceeds that caused by non-thermal insulation, no thermal insulation is needed. Therefore, periodic kiln should decide whether to take insulation measures by calculating specific heat and heat loss.


(3) Because of the high porosity of insulating refractory bricks, they can not bear excessive load, and should avoid contact with molten metals, slag and high temperature blast furnace dust.


(4) The strength of it is low. When building heat-insulating refractory bricks, the joints between bricks and expansion joints should be arranged correctly so as to avoid extrusion of bricks and stones due to expansion. Thermal insulation refractory bricks should not be subjected to strong mechanical vibration, impact and friction.


(5) The reburning line of insulating refractory bricks shrinks considerably, and the maximum service temperature shall be lower than the allowable dry burning temperature, and shall not exceed the allowable temperature.


(6) Thermal insulation refractories differ greatly from heavy refractories, and thermal shock stability of thermal insulation refractory bricks is poor. When using them to build kiln lining, the temperature should not rise or fall too fast, otherwise the lining will break and damage. For the insulating refractory bricks built on the outer lining, reinforcement measures must be taken. For example, it is reinforced by steel plates or metal tie rods.



After listening to our introduction, do you think insulating refractory bricks are widely used? With the development of industry, more and more refractory bricks are produced by people. If you want to buy suitable insulating refractory bricks, please choose us, our company is committed to the production of refractory bricks and other refractories. If you have any questions, please ask us in time.