New building materials——Aluminum silicate needled blanket

Aluminum silicate needled blanket is a kind of refractory material. It is based on the aluminum silicate as raw material, adds some accessories, the technology of resistance furnace, the cloth cotton settlement, plastic needle, high stable cutting, and weighing packaging process and made of.

Aluminum silicate needled blanket can be different according to the production process can be divided into silk throwing acupuncture on and blowing system. Two. Especially double punching process, made the quality of the products is much higher than the ordinary type of aluminum silicate needled blanket. The different production process led to its use is also different, but its performance is basically the same.

Thermal conductivity of aluminum silicate needled blanket with low, good heat insulation effect, low thermal capacity, to make good use of to improve the heat rate, light weight, strong shock resistance, good extensibility, and good insulation properties. Aluminum silicate needled BLANKET SET fire-resistant insulation in one, and its chemical stability strong, does not contain any binder. It has a high tensile strength, good performance of sound absorption and noise reduction. Application of aluminum silicate needled blanket in various fields is also very extensive, high temperature and heating equipment wall lining used in the chemical industry, used in high-rise building fire insulation in buildings.

The application of ceramic fiber refractory material

Application of ceramic fiber refractory material widely, now to introduce its is mainly used to:

1. The door of various insulation industrial kiln mouth seal, curtain.
2. The high temperature flue, wind tube bushing, expansion joint.
3. Petrochemical equipment, containers, pipelines and heat insulation, thermal insulation.
4. Under the environment of high temperature protective clothing, gloves, helmet, helmet, boots.
5. Automobile engine porcelain heat shield, heavy oil engine exhaust pipe package, Speed Racer composite friction brake pad.
6. High temperature liquid transfer pump, compressor, gas and valve packing, gasket.
7. High temperature electrical insulation.
8. Fire doors, fire curtain, refractory blanket, then spark with cushions and insulation cover fire sewing products.
9. Aerospace, aviation industry with insulation, insulation materials, friction brake pad.
10. Cryogenic equipment, containers, pipelines, heat insulation package.
11. The high-grade office archives, vault, safes and other important places of adiabatic, fire compartment, fire automatic shutter

Scientific analysis of castable “appears white hair” phenomenon and effective solution

Castable material in using process often can see high alumina cement castable appeared on the surface of hanging “frost”, “long hair” “powder” “powder” phenomenon. In the common refractory castable surface and water to have loose gelatinous precipitate. These “frost” is because the cement particle surface castable not hydrated in water, forming supersaturated solution, then precipitated alumina sol and hydrated calcium aluminate induced. In fact, “white box” is not affect castables performance, but too much can cause rough skin on the construction, affecting the appearance.

Reason of castable long white: containing alkali refractory raw material, such as calcined alum refractory aggregate in, calcination sticky superior, as calcium aluminates cement castable. All kinds of powder, such as a variety of fine powder, silicon powder and kyanite; there are also contains alkali additives, such as reducing agent, coagulant, explosion-proof toughness. These materials often contain a small amount of alkali, the alkali, some can be dissolved in water, especially the dispersing agent of alkali, almost all into the wood. These “base” by capillary hole to the hardening decent migration, arrives at the table and then, the formation of carbonate and C02 reaction in the air.

Solution for casting material surface “frost” phenomenon:

1. Choosing low alkali content of refractory materials;
2. As soon as possible out of the water, drying, carrier to eliminate sodium alkali, stranded in the construction of the body, not to migrate to the surface.
3. The castable airtight, covered with plastic film, thereby preventing the moisture with alkali to migrate to the surface.
4. Improve the refractory castable viscosity and rapid hardening (reduce sodium migration velocity).
5. Strengthen quality control, strict control of water, to prevent too much water.

Functional refractories introduction

What is the functional refractory material? Functional refractory material is a kind of special refractory material to form with the development of iron and steel metallurgy continuous casting technology. Also known as metallurgical refractory material. Or it can be defined as: functional refractory material is with special or special preparation process with special properties and structure of a kind of high-grade refractory materials, plays a role in the process of using specialized in high temperature. In a sense, can be called refractory functional element.

Refractory products currently include functional refractories are: sliding gate, long nozzle, stopper, submerged entry nozzle (also known as the continuous casting three pieces), permeable brick and fixed diameter nozzle. Each product plays a role in the use of special casting process, such as control flow, air blowing agitation; prevent the two oxidation protective casting, decision flow field of molten steel in the crystallizer.

Functional refractories are presented as a separate refractory material, not only because they are single member in the form of application and the special function in use, but also in the fact that this kind of material is required to meet the usually more demanding conditions of use of the special function, to meet the special structure using function according to the special manufacturing process.

Compared with other steel smelting furnace lining refractory products, to a certain extent, the quality which may affect the lining service time, and functional refractory material quality, it may affect the whole casting process can be. This requires a functional refractory material not only with the conventional contact of liquid steel, slag and liquid refractories also to have the advantages of high temperature resistance, basic function, slag and liquid steel erosion and, according to different conditions, with special or special requirements in structure, material, production technology and process in the use of safe and reliable performance.

U.S. levy anti-dumping taxes on China Refractories

U.S. Department of Commerce preliminary ruling made ​​by the first half of last year, China's exports to the U.S. decision to impose refractories ~ 91.16% 84.89% anti-dumping duty. The U.S. Commerce Department's announcement that day showed specific products being taxed at least 90% of silica containing silica brick.

This acid refractory is mainly used for masonry coke ovens, blast furnaces, glass kilns and other high-temperature furnaces.

Chinese exports to the U.S. silica brick case began in November 2012. Utah, a refractory company complaint, claiming that Chinese companies of dumping in the United States, asked the U.S. Department of Commerce initiated anti-dumping investigation, the dumping margin was made ​​up 118.47% ~ 290.12%.

U.S. Department of Commerce statistics show that in 2011 Chinese exports to the U.S. totaled about $43,240,000 silica brick, but in 2012 the total value of exports to the U.S. fell to $25.7 million sharply, a decline of nearly 40%.

For the United States frequently waving "trade stick", Chinese Ministry of Commerce has repeatedly stressed that trade protectionism is not only unfair to him, the country, there is no advantage to domestic companies, do not want the United States to measure high-sounding but actually with a strong political background to implementation of trade protectionism, but should abide by its commitment to oppose trade protectionism, with a more rational approach to properly handle trade frictions

Refractories used in steel smelting

Blast furnace refractories:

Development of blast furnace ceramic cup increasingly common, but require high corrosion resistance of refractories application to ensure its life extended. In addition to changes in the design of the refractory material respects, great changes have taken place, such as a micro porous carbon brick ordinary charcoal instead of the past in order to reduce the penetration of molten iron. Clay refractory bricks used as raw material can adapt to the requirements stemming mouth of iron. Grouting method using blast furnace repair backing backing can effectively prevent the erosion of hot air, thereby extending the life of the blast furnace lining.

Clay refractory bricks used as raw material can adapt to the requirements stemming mouth of iron. Grouting method using blast furnace repair backing backing can effectively prevent the erosion of hot air, thereby extending the life of the blast furnace lining.

Converter refractories:

In steelmaking, the kind of water-cooled technolovgy and suspension systems are in the upper part and the lower cone barrel parts BOF shell has been applied, thus reducing the converter furnace deformation, extending converter lining life, improve productivity converter. These new technologies have some impact on the use of refractories. So that the converter furnace furnace up to 4000 more than the average, combined with gunning, the application of high lime and dolomite applications and slag splashing technology, furnace over 10,000 times is not a problem. This is the direction of development of refractories producer worth attention.

Submerged nozzle for continuous casting:

Since the development of the system of casting tundish transfer station from the past into the present effects of cast steel quality and increase the productivity

of the metallurgical vessel. Therefore, many functional materials gradually applied in the middle of the package, such as slag dam, impact plates, filters, plugs, etc. argon permeability.

Submerged nozzle as an important function of continuous casting refractories, research carried out mainly focused on two aspects, one is to improve the corrosion resistance of slag line, the second is to reduce the inner wall of Al2O3 attachment. Take the ZrO2 content increased 88%, as well as a good measure of the particle size distribution can reduce the thermal expansion coefficient and porosity of products, improve the density improvement slag resistance.

Species and characteristics of clay

Alumino silicate clay is dominated by rocks, such as feldspar pegmatite granite, porphyry, gneiss, etc. The long-term weathering, and often through water transport and deposition are too many fine mineral mixture, its main chemical composition of SiO2, Al2O3, and water of crystallization. With different geological formation conditions, may also contain small amounts of alkali metal oxides, alkaline earth metal oxides and coloring oxides.

Varieties and uses a lot of clay, often according to mineralogical, geological origin, chemical composition, physical properties or industrial uses clay classification.

1. More clay minerals in the main types can be divided kaolin clay series, smectite and illite clay series. 
2. According generation, the clay can be divided into the native clay (Primary clay) and secondary clay (Secondary clay), the native clay is the generation after feldspar weathering of silicate hydrous kaolin and other minerals, quartz, etc., is not completely broken weathered residual debris in situ, and soluble salts were dissolved; secondary raw clay is a former clay transferred under dynamic conditions to the rest of the natural crystalline clay again.
3. According to the plasticity of clay can be divided into soft clay (strong plasticity clay), semi-soft clay (clay plasticity) and hard clay (clay plasticity weak), mostly secondary soft clay clay, because fine particles dispersed degree, so plasticity; hard clay and more by diagenesis ancient community, and the lack of free water is not easy to dip into the bulk, plasticity poor.

Some Western industrialized countries often comes down to the clay six categories, namely: Kaolin (Kaolin), fire clay (Fire clay), ball clay (Ball clay), bentonite (Bentonite), bleaching earth (Fuller, s earth) and the general clay (Common) where bentonite, fuller's earth and ordinary clay mainly composed of montmorillonite, illite and chlorite, etc., poor fire resistance.

Classification and habits at home and abroad, the refractory clay Category: kaolin, ball clay and fire clay. Natural clay minerals according to the above classification is not always a sharp distinction between, and sometimes a clay can contain a variety of clay, but the performance is also superimposed on each other, such as mineral composition and chemical composition of many hard clay and kaolin are very close; many balls soft refractory clay and the clay of the same physical properties. Regardless of how the kind of clay, clay determine its performance properties.

Technical characteristics of the vacuum fiberboard

Low thermal conductivity, heat capacity; excellent thermal stability and thermal shock resistance; high strength and good toughness.

Application:

1. Industrial furnace wall lining, masonry insulation layer;
2. High-temperature furnace kiln liner, kiln cars, door tailgate, kiln furnace partition plate;
3. High-temperature, heat equipment insulation, thermal insulation;
4. Aerospace, shipbuilding insulation, fire protection, sound insulation.

Working temperature:

Depending on the type of heat source, atmosphere and material conditions.

Production

Various aluminum silicate fiber, using the corresponding ordinary type, standard, high purity type, containing zirconium silicon fiber cotton as raw material,

using vacuum filtration processes or dried into the legal system.

In addition to a variety of aluminum silicate fiber corresponding bulk silicate fiber cotton excellent performance, hard texture, excellent toughness and strength, excellent fire resistance, thermal insulation properties. Heating is not expansive, light weight, convenient construction, can be cut bent and is ideal for energy-saving materials furnaces, heat pipes and other equipment.

Introduction of special refractories

Special Refractories is a new inorganic non-metallic materials developed on the basis of traditional ceramic and refractory materials in general on. It has the following characteristics: melting point, high purity, good chemical stability and thermal shock resistance.

Special refractories include high melting point oxides and refractory compounds and derived therefrom, metal ceramics, high temperature coatings,

high temperature fiber and reinforced materials.

Compared with traditional ceramics and refractories, special refractories, high purity, high melting point, good electrical, thermal, mechanical and chemical properties, Thus, can use for high precision and advanced science and technology; in the manufacturing process, raw materials generally after burned. In addition to the traditional method of molding, but also using new technology vapor deposition, hot and so on. Micron powder molding compound material is calcined at high temperatures and require a protective atmosphere, the article can be made thin (translucent).