Monday, May 18, 2015

Features Of High Alumina Refractories

Aluminium Oxide (Al2O3 ) or alumina is one of the most versatile of refractory ceramic oxides and finds use in a wide range of applications. High alumina refractories are alumina refractories containing more than 45% alumina.

High alumina bricks is made of high-quality bauxite chamotte as raw materials by shaping at high pressure and sintering at high temperature. Alumina is one of the most chemically stable oxides known, which offers excellent hardness, strength and spalling resistance, which imparts high alumina refractories great features.

The alumina content ranges from 45 to 100%. The refractoriness of high alumina refractories increases with increase of alumina content. So high alumina refractories have high refractoriness and excellent high temperature performance.

High alumina refractories are a kind of acid refractories. Therefore, they have good resistance to acid slags. High alumina refractories are also featured with high cold crushing strength. As the alumina content increases, the cold crushing strength also increases. This makes them to bear more load during use. The high hardness of alumina imparts high wear and abrasion resistance.

Manufacturing cost and price of these brick increase more rapidly with % alumina content, so it is essential to determine experimentally or by test installations the most economical alumina content for each service. In some areas such as the regenerators, fire clay bricks can be used as a replacement for high alumina refractories.

Due to severe service conditions prevailing in modern reheating furnaces, there is an increasing tendency to use more and more of high alumina bricks in place of conventional fireclay bricks.  The applications of high alumina refractories includes the hearth and shaft of blast furnaces, ceramic kilns, cement kilns, glass tanks and crucibles for melting a wide range of metals.

Sunrise Refractory is refractory supplier from China, providing high quality high alumina refractories in various shapes at competitive prices.

No comments:

Post a Comment