Refactory mixes

Types of refractory mixes

Every year we produce about 20000mt of refractory mixes and shapes with a very wide range of properties using about 50 kinds of raw materials, both of Russian and foreign origin. Therefore, you can choose the most suitable material for the specific operating conditions that will perfectly combine refractoriness, heat resistance, thermal conductivity and strength. The mixes can be applied by casting, gunning or ramming. We can manufacture refractory shapes and lined steel structures of the most complex configuration weighing from a few kilograms to 100 tonnes.

Hundreds of enterprises of different industrial sectors from Estonia to Khabarovsk and from Far North to Turkmenistan have been using our refractories for many years.

The products are manufactured in accordance with technical specifications and have all required sanitary certificates. Each consignment is accompanied by the certificate of quality and usage instruction. Our plant has all the necessary licenses. We design furnaces and linings, give advice on selection of refractory castables and provide technical assistance during the installation work.Алитер-Акси

Types of refractory castables produced by “ALITER-AXI”

LIGHT WEIGHT ALAKS MIXES have low density (0.4-1.7 g/cm3) and thermal conductivity. The mixes consist mainly of light weight porous fillers (vermiculite, perlite, expanded clay, diatomite, lightweight chamotte, bubble corundum) and calcium aluminate cements. A number of ALAKS mixes contain modifying additives, mixes for high temperature application have complex multicomponent binder matrix.

REGULAR DENSE ALKOR MIXES are based on alumina silicate fillers (chamotte, andalusite, mullite, bauxite, corundum, tabular alumina) with different density, chemical and mineral composition, and calcium aluminate cements. Cement content is more than 15%. After mixing with water, the mix hardens due to hydratation of calcium aluminate and forms solid refractory castable. Hydrates decompose when heated, water leaves castable and as a result forms pores, structure of castable loosens, strength decreases. Moreover, calcium oxide, which is a part of cement, interacts with aluminosilicate fillers and as a result forms low temperature eutectics, so that high cement castables refractory property is lower than refractory property of their fillers and cement, their high temperature properties are low (except for corundum castables ALKOR 94, ALKOR 96 and castables with fine corundum matrix ALKOR 56/5).

DEFLOCCULATED MEDIUM-CEMENT CASTABLES ALICAST AND ALIT, LOW-CEMENT, ULTRA-LOW CEMENT AND NO-CEMENT ALKORIT AND ALIFEST contain 7-12% and less than 5% of cement respectively, that is why they don’t have these drawbacks. The castables have complex and balanced composition: they contain ultrafine powders, deflocculants, regulators of setting and hardening mechanisms and time. The green strength of these castables is often lower than that of high-cement castables, however, they strengthen substantially already during low temperature dry-out, and at temperatures around 600° a ceramic bond starts to form. Castables ALICAST, ALIT, ALKORIT and ALIFEST are characterized by high temperature, abrasion and chemical resistance, high density and strength. Low-cement castables exhibit high refractory properties due to low content of cement and thereafter calcium oxide, a number of them correspond to high-quality bricks according to their characteristics.
While during preparation of high-cement castables you have to add 9-15% of water into the mix, for mixes ALICAST, ALIT and ALKORIT 3.5-7% will be enough. The lower the amount of cement in the mix is, the more negatively water overdose influences the castable mechanical characteristics. Therefore, the preparation of low-cement mixes ALKORIT requires the use of intensive mixers and vibration during installation. If this is not possible, you should use ALICAST mix or self-flowing mixes (index “S” in the name). After mixing with a small amount of water self-flowing mixes form castable that flows and degasifies without being exposed to vibration. It is not possible for ordinary castables without adding excessive amounts of water, which reduces their mechanical properties. Self-flowing castables and ALICAST castables have all the advantages of low-cement castables (low porosity, high density, strength, abrasion-resistance, temperature resistance), they also have a smooth specular surface. They can also be used for hard-to-reach places of lining, thin layers application and for linings repair by casting.

ALIGUN MIXES are specifically designed for gunning. The difference between ALKOR and ALIGUN mixes is quite significant, the latter have much lower rebound due to their viscous consistence and quick setting. Bear in mind that most of ALIGUN mixes cannot be casted without retarders.

ALIRAM MIXES are designed for abrasion resistant linings. They have an exceptionally high strength (up to 200 N/mm2) and abrasion resistance (less than 3 cm3 according to ASTM С704).

SILICON CARBIDE CONTAINING MIXES are highly resistant to temperature changes, alcalies and abrasion, thereby they are widely used in the cement, steel and power industries.

REFRACTORY MORTARS AND MASTICS are designed to make an interconnection between refractory bricks or shapes, sealing of linings and thermal units. Due to their high adhesion to the surface of refractory shapes, castables and steel, mortars and mastics based on chemical binders (in some cases, based on hydraulic binders as well) can be used as protective coatings, repair mixtures and refractory glue. Mortars are made as dry powder mixture which must be mixed with water before usage. ALIPLAST mastics, unlike mortars, are mixed not with water but with a liquid binder. ALITER-AXI manufactures mortars based on hydraulic and chemical binders. Mastics are always based on chemical binders. The size of filler particles in mortars and mastics does not exceed 1 mm. The thickness of mastic or mortar layer shall not exceed 5 mm.