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.