Shandong Guangming Super Refractory Fiber Co., Ltd.
manufactures ceramic fiber and products with good and excellent quality. Insulating Bio-Soluble refractory refers to refractories with high porosity, low bulk density and low thermal conductivity. Insulation bio-soluble refractories are also called lightweight refractory. It includes insulating refractory products, refractory fiber and refractory fiber products. Insulating refractory is characterized by high porosity, general 40% ~ 85%; Bulk density is low, generally less than 1.5 g/cm3; thermal conductivity is generally less than 1.0 W (m · k). It is used as the insulation material of industrial kiln, and it can decrease furnaces heat loss, save energy, and reduce the weight of the thermal equipment. Heat insulation bio-soluble refractories in week in mechanical strength, wear resistance and slag erosion resistance. It should not be used in the bearing structure of furnaces and direct contact with molten slag, furnace charge and molten metal parts, etc. Insulation refractory products refer to the porosity of no less than 45% of refractory products. There are many kinds of insulating refractory products. Their classification methods mainly include the following kinds:
(1) According to temperature, it can be divided into low temperature heat insulating refractory (using temperature 600 ~ 900 ° C), medium temperature and heat insulation refractory (using temperature 900 ~ 1200 ° C) and high temperature heat insulation bio-soluble refractory (temperature greater than 1200 ° C).
(2) According to the volume density, it can be divided into general lightweight refractory (volume density of 0.4 ~ 1.0 g/cm3) and ultra lightweight refractory (bulk density less than 0.4 g/cm3).
(3) According to the production methods, it can be divided into burning method, bubble method, chemical method and the method of porous materials.
(4) According to the product shape, it can be divided into setting insulating bio-soluble refractory products and amorphous insulating refractory products. Insulating refractory products and dense bio-soluble refractory products are different, the main methods are burning joining method, bubble method, chemical method and the method of porous materials: (1) burning joining method. The method is to sawdust and other flammable or can be sublimated additives into the mud material. Mixing, and then used to squeeze billet, half dry or mud casting molding, drying after firing. Combustible or can be sublimated additive in the process of firing burn, leaving empty hole, be insulating refractory products.
(5) Bubble method. The method is to add foaming agent and water into the whisk machine and mix them into tiny bubbles. Then add the foam into slurry and inject model, drying them together at 1320 °C to 1380 °C (for high aluminum heat insulation refractory brick). Then the product is shaped after processing.
(6) The chemical method. It uses chemical reaction to produce gas in the process. It usually use chemical reactions such as carbonate and acid, metal powder acid, caustic and aluminum powder, etc. The chemical reaction must be slow and in control, or the bubble will disappear by mechanical disturbance when poured into the mold. We can add inhibitors such as manganese dioxide and hydrogen peroxide. In fine powder raw material slurry, we can mix with bubbling reagent to obtain stable foam slurry, and inject model, then it comes to shape by drying and burning. Using the method, we can make pure oxide insulating refractory products, whose porosity can reach 55% to 75%.
(7) Porous materials method. The method uses expanded perlite, expanded vermiculite and diatomite and natural lightweight materials such as all kinds of artificial manufacturing hollow ball, and adds some binder. By mixing, molding, drying, and firing process, it can be made into insulating refractory products.