Carbon products, corundum and silicon, Dnipropetrovsk region.

Refractories, or refractory materials, are magnesite non-metallic substances with a fire resistance of at least 1580—1650 degrees Celsius. Such materials are used for lining (lining) blast furnaces and other furnaces for melting, firing, evaporation, distillation of metallic and non-metallic elements - that is why it is extremely important to choose high-quality refractory materials.
A distinctive property of refractories is preservation of the object's shape and functional characteristics at any, even the most extreme, temperatures. Most often, such a product is used in metallurgy - without it, the construction of not a single thermal unit is complete - these materials have no equal in terms of resistance to fire, pressure and high temperatures!(//tractor-service.com)

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