Mullite and mullite-corundum refractories
Mullite and mullite-corundum refractories contain more alumina than fireclay ones and work at higher temperatures and loads. They are used in the roofs and walls of high-temperature furnaces in metallurgy and other industries.
Dense products are made to GOST 24704, lightweight МЛЛ to GOST 5040, some grades to manufacturers' specifications. The number in dense grades is the alumina content, %; in lightweight grades it is the apparent density, g/cm³.
Grades and types
МЛС-62, МЛС-62-22, МЛУ-62
Dense mullite products for the working lining layer. МЛС-62 to GOST 24704, МЛС-62-22 and МЛУ-62 to manufacturer's specifications; 62 is the alumina content, %. Used in furnace roofs and walls where the temperature or load is higher than fireclay can withstand.
МЛЛ-1.0, МЛЛ-1.3, МЛЛТ-1.0, МЛЛТ-1.3
Lightweight mullite products: МЛЛ to GOST 5040, МЛЛТ to manufacturer's specifications. The number in the grade (1.0 or 1.3) is the apparent density, g/cm³. Lightweight bricks reduce masonry weight and heat losses; they are used in the insulating layer or in a working layer without mechanical loads and abrasion.
МЛТ-1.0, МЛТ-1.3
Insulating mullite products for the insulating layer behind the working lining. Standard as per the grade certificate (GOST 5040 or manufacturer's specifications). The number in the grade is the apparent density, g/cm³: the lower it is, the lighter the product and the lower its thermal conductivity.
МКС-72, МКС-80, МКС-90
Dense mullite-corundum products: МКС-72 and МКС-90 to GOST 24704, МКС-80 to manufacturer's specifications. The number in the grade is the alumina content, %: the higher it is, the higher the permissible temperature and resistance. For high-temperature and high-load zones where fireclay and mullite wear faster.
МКУ-90, МКУФ-90
Compacted mullite-corundum products: МКУ-90 to GOST 24704, МКУФ-90 to manufacturer's specifications. The compacted structure reduces porosity, so the products resist slag and gas penetration better. For the most heavily loaded lining zones.
МКП-72
To manufacturer's specifications. Mullite-corundum products for units with high mechanical and thermal loads. We select the grade and shape according to the masonry drawing and the operating conditions of the unit.
Can’t find the grade you need? Write to us — we supply other items too.
In brief
| Parameter | Value |
|---|---|
| Standard | dense products — GOST 24704, lightweight МЛЛ — GOST 5040; some grades — manufacturers' specifications |
| Grades | МЛС, МЛУ, МЛЛ, МЛЛТ, МЛТ, МКС, МКУ, МКУФ, МКП |
| Applications | high-temperature and high-load zones where fireclay cannot cope |
| Designation | the number in dense grades is the alumina content, %; in lightweight grades — the apparent density, g/cm³ |
| Supply | under contract with legal entities, delivery across Kazakhstan |
How to choose a grade
The higher the alumina content (МЛС-62 → МКС-72 → МКС-90), the higher the permissible operating temperature and load resistance. The grade is chosen by the temperature and conditions of the zone.
Dense products (МЛС, МКС, МКУ) go into the working layer, lightweight and insulating ones (МЛЛ, МЛТ) into the insulating layer of a multilayer lining.
Laying and installation
For laying mullite and mullite-corundum products, a mortar of the same group is selected so that the joint works like the brick. Refractory mortars →
Frequently asked questions
What is the difference between МКС-72 and МКС-90?
The alumina content: the number in the grade is its share, %. МКС-90 withstands higher temperatures and loads, МКС-72 suits less severe conditions.
When is mullite brick needed instead of fireclay?
When the temperature or load in the zone is higher than fireclay can withstand: in the roof and walls of high-temperature furnaces and in zones with temperature fluctuations.
What should mullite-corundum products be laid with?
A mortar of the same group — mullite-corundum or high-alumina. We will select the grade for the brick.
How can an enterprise order mullite-corundum bricks?
Send a request with the grade, quantity and delivery city or attach a specification. We will prepare a commercial offer, sign a contract and deliver the products across Kazakhstan.
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Send a request
Send grades and quantities or a specification via WhatsApp or email — we will prepare an offer. We reply during business hours, Mon–Fri 9:00–18:00.
Write on WhatsApp Send an email +7 (778) 700-26-38
Requests sent outside business hours are processed on the next business day.