Application of unshaped refractory materials

Unshaped refractory material is composed of reasonable distribution in the granular and powder and binder not forming and firing directly use of the refractories. Then what is the different unshaped refractory material application area, let us see it.

1. Ironmaking system.

• Alumina silicon carbide carbon refractory castable for blast furnace trough.
• As with hot-air burner refractory pouring castable lining.
• Torpedo type iron waterwheel partial or full using refractory castable, can also use refractory coating to repair.

2. Rolling system.

• All available unshaped refractory lining, steel forging heating furnace.

3. The steelmaking system.

• The cement rotary kiln.
• Glass tank furnace.
• Ceramic kiln.

4. Other industrial system.

• Petrochemical industry, ferrous metallurgy, fluidized bed boiler.

5. Building system.

• Refractory coating repair of BOF and eaf.
• Slag splashing.
• Alumina magnesia castable making converter lining.

Above is the simple introduction application of unshaped refractory materials, thank you for reading, more detailed information can contact us, we will try our best to answer your questions.

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.

Application of refractory aggregate and powder in castable.

The unshaped refractory castable, refractory aggregate amount is generally 63%~73%, acting as a framework, can significantly affect the performance. Refractory powder dosage is 17%~37%, filling aggregate porosity and improve the construction resistance and so on. Some refractory powder, such as clay and ultra – fine powder, or a good bond. The ideal particle gradation is the gap caused by the coarse aggregate is just fine aggregate void filling, between the two has been refractory powder filled, no no surplus, to achieve the greatest packing density, in order to get the best performance.

Refractory aggregate divided into coarse and fine aggregate. Average particle size greater than 5mm is referred to as the coarse aggregate; 5mm and 5mm to 0.09mm is referred to as the fine aggregate. Habit will 5~0.15mm particles known as fine aggregate. Aggregate critical particle size depends on the thickness of the lining of the body, as shown in the following table. At present, the refractory critical particle size is reduced tendency, generally use 8mm or 5mm, pump feeding with 3mm. It should be noted that, in the preparation of unshaped refractory materials, the refractory aggregate gradation shall request the composite table technology.

In the production of unshaped refractory materials used as refractory materials, refractory aggregate and powder: bauxite, clay material, semi silica raw material, silicon material, magnesium material, kyanite group mineral raw materials, mullite, alumina, corundum, spinel raw material, silicon carbide, silicon nitride, chromium iron, zircon etc..

After the destruction of these refractory raw material, crushing, unshaped refractory materials to prepare the composite requirements of raw materials, to ensure the quality of the product, before use must be tested raw materials.

Use of recarburiser

Carbon additive is an additive used in steel making. It is an essential raw material for the production of high-quality steel. Further, also the production of the electrode paste material.

After pressing graphite powder,

can greatly increase the amount of scrap castings production, reducing the amount of pig iron or no iron in an electric furnace smelting, will increase carbon agent in the middle, (the latter part of the furnace discharge material put Recarburizer) added measure is 1-3% metal content. Recarburizer characterized by carbon absorption in liquid iron in effect, does not return slag, using carbon agent can greatly reduce the casting cost of production.

Advanced refractory and coatings are widely used in metallurgical industry, steel core light industry, electrical industry, carbon brush, electrode in battery industry, fertilizer industry catalyst. Graphite after processing, can produce graphite, graphite paper, graphite sealing materials and other graphite products, has become an important non-metallic mineral raw materials in various industrial sectors.