What are the main refractories used in large steel plants in China? What are the characteristics of

Refractory bricks and refractory clay.

Expansion partitions. magnesia carbon brick zhi

DAO magnesia carbon brick aluminum-magnesia carbon brick burnt magnesia brick magnesia chrome brick is a class of inorganic non-metallic materials with a refractory degree of not less than 1580. Refractory resistance refers to the Celsius temperature at which the refractory conical specimen resists high temperature without softening and melting without load. However, the definition of refractory alone is no longer a complete description of refractories, and 1580 is not absolute.

It is now defined as a material whose physical and chemical properties allow it to be used in a high-temperature environment, called a refractory material. Refractories are widely used in metallurgy, chemical industry, petroleum, machinery manufacturing, silicate, power and other industrial fields, and are the largest in the metallurgical industry, accounting for 50% and 60% of the total output.

Refractory clay is a refractory material.

One of the most basic and widely used raw materials in the BAI material industry. Special refractory materials are mainly zirconia and oxygen.

Ronghua titanium, beryllium oxide, cerium oxide, thorium oxide, yttrium oxide, etc. These raw materials have different degrees of resistance to various slags, but because there are not many raw materials, they cannot be used in a large number of applications in the refractory industry, and the rotary kiln can only be used in special circumstances, so it is commonly known as special refractory raw materials. There are many kinds of refractory raw materials, we can roughly divide them into the following categories, from these refractory raw materials, you can analyze which ones need a general mill for processing and milling.

The raw materials of alkaline refractories are mainly magnesite (rhododite), dolomite, lime, olivine, serpentine, and high alumina oxygen raw materials (sometimes neutral), which have strong resistance to alkaline slag and are mostly used in masonry alkaline furnaces.

Metallurgical refractories: bias for ironmaking.

acidic, like siliceous, clayey, high alumina, etc.; Steelmaking with alkaline plates, such as magnesia, magnesia carbon, magnesia calcareous, magnesia chromium, etc., continuous casting with clay, silice, etc.

In addition, there are zirconium, hot-pressed small carbon blocks, amorphous refractories, etc., and many other types of cement, glass, non-ferrous metals, etc., are more miscellaneous, and large, medium and small enterprises are different.

It is recommended to buy a refractory and take a look, a simple and fan-like understanding, Li Hongxia's "Refractory Manual" is good.

Refractory materials commonly used in industry, special materials include AZS bricks, corundum bricks, direct bonded magnesium and chromium, silicon carbide bricks, silicon nitride combined with carbide bricks, nitrides, silicides, sulfides, borides, carbides and other non-oxide refractories; Refractory materials such as calcium oxide, chromium oxide, alumina, magnesium oxide, and beryllium oxide. Frequently used thermal insulation refractory materials include diatomaceous earth products, asbestos products, thermal insulation boards, etc. The amorphous refractories often used include charging materials, ramming materials, castables, plastics, refractory mud, gunning materials, projection materials, coatings, light refractory castables, gun mud, etc.

Rayfa Refractory Technology provides:

The refractory materials commonly used in steel mills refer to inorganic non-metallic materials (including refractory mineral raw materials) and their products with a refractory degree of not less than 1580 degrees. The main raw materials of refractory materials are natural raw materials, industrial raw materials and synthetic raw materials. Using different processes, these raw materials can be processed and made into various sintered refractory products, unburned refractory products, fused casting refractory products, refractory fiber products, thermal insulation refractories and unshaped refractories.

Classification by chemical properties; Acid refractories, neutral refractories, alkaline refractories (performance indicators, chemical composition are not listed for the time being).

Classified by chemical mineral composition; Silicon products, aluminum silicate products, magnesium products, dolomite products, chromium and chromium-containing products, zirconium products, carbon products, nitride products, silicon carbide products, pure oxide products.

Classification by material appearance; Refractory bricks, amorphous refractories, refractory fibers.

Rongsheng refractories provide.

Iron ditch castables, cannon mud, spray paints, repair materials, and a large number of refractory bricks.

Refractories in steel millsThe refractories generally used in steel mills are: magnesium oxide or magnesium oxide-calcium oxide, chromium magnesium, silicon refractories, refractory clay, high alumina, and carbon 6 categories.

It is mainly used in the lining of steelmaking furnace and ironmaking blast furnace, the lining of ironmaking hot blast furnace insulation, heat storage bricks, the lining of ladle for bearing and transporting metal and slag, the lining of furnace for heating billet in the next process, and the lining of the flue and blast furnace body for conducting hot gas.

Finishing from the lightning method refractory technology.

There are several ways to classify refractories:

According to the classification of the form of supply, it can be divided into two categories: fixed (refractory bricks, and alkaline plates and aluminum bricks) and amorphous refractory materials (refractory castables, bauxite cement castables, crust refractory castables, and high alumina castables).

According to the classification of chemical properties, it can be divided into three categories: acid refractories, alkaline refractories and neutral refractories.

According to the main mineral chemical components of refractories, they can be divided into: silicon refractories, aluminosilicate refractories, magnesia refractories, magnesium spinel refractories, magnesia-chromium refractories, magnesium dolomite refractories, dolomite refractories, carbon composite refractories, high-alumina refractories, chromium refractories, zirconium refractories, etc.

According to the different classification of refractoriness, it is divided into ordinary high-grade super refractories; According to the classification of bulk density, it can also be divided into light and heavy refractories. According to the different classifications of nature and size, it is divided into standard type, general type, special-type special type refractory and so on.

There are many types of refractories, and in the production and use of refractories, a classification method in response to this has been adopted in view of a certain need. Answer: At present, the classification methods of refractory materials are roughly as follows:

1) According to the degree of refractory, it can be divided into 1580 and 1770 ordinary refractories; 1770 2000 Advanced Refractories; 2000 3000 Premium Refractories; More than 3000 super refractories.

2) According to the shape and size, it can be divided into standard type, general type, special-type, brick-type, special type and super special type products.

3) According to the molding process, it can be divided into natural rock cutting, mud pouring, plastic molding, semi-dry molding and vibration, ramming, melting and casting molding and other products.

4) According to the firing process, it can be divided into fired products, unfired products and cast products.

5) According to the chemical-mineral composition, it can be divided into aluminum silicate products (clay bricks, high-alumina bricks, semi-silica bricks), siliceous products (silica bricks, fused silica sintered products), magnesia products (magnesia bricks, magnesia aluminum bricks, magnesia-chrome bricks, etc.); carbon products (carbon bricks, graphite bricks, etc.); dolomite products; zircon products; Special refractory products (high-purity oxide products, insoluble compound products and high-temperature composite materials), etc.

Acid refractories use silicon oxide as the main component, and silica bricks and clay bricks are commonly used. Silica celery brick is a silica product containing more than 93% silicon oxide, the raw materials used are silica, waste silica bricks, etc., its resistance to acid slag erosion is strong, the load softening temperature is high, and the volume does not shrink after repeated calcination, and even expands slightly; However, it is susceptible to the erosion of alkaline slag and has poor thermal vibration resistance. Silica bricks are mainly used in thermal equipment such as coke ovens, glass melting furnaces, and acid steelmaking furnaces.

Clay bricks are made of refractory clay as the main raw material, containing 30% 46% alumina, which is a weakly acidic silver refractory material, with good thermal vibration resistance, corrosion resistance to acid slag, and is widely used.

Neutral refractories have alumina, chromium oxide, or carbon as the main components. Corundum products containing more than 95% alumina are a high-quality refractory material with a wide range of uses. The chromium bricks with chromium oxide as the main component have good corrosion resistance to steel slag, but the thermal vibration resistance is poor, and the deformation temperature of high temperature load is low.

Carbonaceous refractories include carbon bricks, graphite products and silicon carbide products, which have a very low coefficient of thermal expansion, high thermal conductivity, good thermal vibration resistance, high high temperature strength, resistance to acid, alkali and salt erosion, and are not wetted by metal and slag of the melting ruler, and are light in weight. It is widely used as a high-temperature furnace lining material, and is also used as an autoclave lining for petroleum and chemical industries.

Alkaline refractories use magnesium oxide and calcium oxide as the main components, and magnesia bricks are commonly used. Magnesium bricks containing 80% of magnesium oxide and more than 85% have good resistance to alkaline slag and iron slag, and have higher refractory resistance than clay bricks and silica bricks. It is mainly used in open-hearth, oxygen blowing converter, electric furnace, non-ferrous metal smelting equipment and some high-temperature equipment.

Refractory materials used in special occasions include high-temperature oxide materials, such as alumina, lanthanum oxide, beryllium oxide, calcium oxide, zirconia, etc., and refractory compound materials, such as carbide, nitride, boride, silicide and sulfide, etc.; High-temperature composite materials, mainly including cermets, high-temperature inorganic coatings and fiber-reinforced ceramics.