| Technical characteristics of alumina cement |
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- Alumina cement (AC) is subdivided into 2 types according to the compression resistance at 72 hours AC-40 and AC-50;
- The hardening process starts no earlier than in 45 minutes and finishes no later than in 10 hours after tempering
- The contents of Al2O3 in the cement is no less than 35%
- One of the most important advantages of the alumina cement is its ability to solidify quickly when tempering
- Durability of the cement in 15-18 hours is sufficient for putting the constructions into operation
- The most favourable temperature for the cement tempering is 15-20° C in the humid environment
- Alumina cement is characterized by releasing a lot of heat within relatively short period of time. This allows the construction work to be carried out during the winter time without the pre-heating the concrete
- The cement is highly stable and resistant to corrosion in any aggressive environment
- Alumina cement is the best astringent for fireproof and heat-resistant concrete at the temperature up to 1700° C
| Field of alumina cement application |
- For lining of some parts of smelting, heating and liquid-ball furnaces
- For a quick rebuilding of wreck industrial building and bridges
- For emergency fixing the leaks in the sea vessels
- For assembly of power lines
- For construction of mines, underground structures, plugging of crevices
- For mineral resource industry
- For a quick foundation and pouring in anchor bolt holes
- For construction works with concrete in winter
- For a rapid plugging-back of well
- For individual repair work and house systems (construction of fireplaces, furnace lining, reconstruction of ventilation ducts and flues)
- And in emergency situations
Alumina cement is successfully used in manufacture of refractory products (brick, block, flagstone), which serve as lining material for different aggregates working at temperature 1300-1700° C.
Alumina cement as hydraulic binding agent is used in bulks, concrete and finished building elements (panels):
- In heaters which work at temperature up to 13000° C
- In industrial engineering
- Building chemistry as a component of solutions and glues
- In adventures
- In individual repair and erection works (flues, air channels, furnaces)
Such wide use of the alumina cement is possible due to its unique abilities, which include:
- Short time of bonding
- Quick increment of mechanical aging
- Immunity to acid salt, sea-water, carbon oxide, methane
- Possibility of use at low temperature (-10° C)
- Guaranteeing of fittings protection
- Phase composition which guarantees perfect mechanical abilities for solutions and concrete
The alumina cement is successfully used in equipping heat arrangements working at temperature up to 1300° C. That's why we recommend it for the construction of fireplaces, furnace lining, flue repair and air channels. The application of this cement makes it possible to use the equipment for a long period of time.
The alumina cement can be easily used at low temperature, even -10° C, and in chemically aggressive environment (chloride, acid salt).
The alumina cement is also used in mining industry due to its particular abilities such as:
- quick increment of aging
- large heat result hydration
- short time of bonding
- immunity to different gases like carbon oxide, methane and hydrogen
Characteristic features of the alumina cement such as short time of bonding and quick increment of mechanical aging make it possible to use this cement in emergency house repair works. One can use it for the preparation of floors, windowsills and lintels.
The production of the alumina cement is strictly controlled. It guarantees its solid chemical composition and good physical properties.
| Chemical element |
Percent contents |
| Al2O3 |
Minimum 40 percent |
| CaO |
Minimum 36 percent |
| SiO2 |
2-4 percent |
| Fe2O3 |
10-14 percent |
| Ordinary refractoriness |
128 sP, i.e. 9 sS |
| Relative density |
3,0 g/sm3 |
| Bulk density |
1,1 g/sm3 |
| Specific surface according to Bline |
3100-3800 sm2/g |
| Grain size, span |
0-63 µ min 80 percent |
| Possible temperature |
-10° C |
| Mineralogical composition |
| Master phase |
calcium monoaluminate |
| Accompanying phases |
Brownmilerite Heptaluminate twelve-calcium Helenite |
| Assembly time in binding |
calcium monoaluminate |
| Accompanying phases |
starts no earlier than in 40 minutes finishes no later than in 6-8 hours |
| Pliability resistance |
6-8 FR in 24 hours |
| Compression resistance |
45-55 FR in 24 hours 60 FR in 72 hours |
It's possible to keep this cement for 3 months due to its goodness and special package. But in practice it turns out that the cement preserves all its properties for 6 months.
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COMPANY
Expanding gypsum-alumina cement
