Description of high alumina cement
High alumina cement is produced by grinding alumina clinkers and calcium material such as lime in a sintering or fusing process. This cement is also known as calcium-aluminium cement.
Kerui Refractory offers high-quality aluminous cement of Russian and international brands, i.e.:
- Russian brands：ВГЦ-I, ВГЦ-II, ВГЦ-III.
- Международная марка: CA50, CA70, CA80.
Characteristics of cement CA50/70/80
| Subject/Sort | CA50 | CA70 | CA80 | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| A600 | A700 | A900 | CA70 | CA70W | CA70S | CA71 | CA80 | CA80S | |||
| Chemical composition | ω (SiO2) ≤/% | 7.8 | 7.5 | 5.5 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 | |
| ω (Al2O3)/% | 50.0 | 51.0 | 53.5 | 68.5-70.5 | 68.5-70.5 | 68.5-70.5 | 69.5-71.5 | 78.0-81.0 | 78.0-81.0 | ||
| ω (Fe2O3) ≤/% | 2.5 | 2.5 | 2.5 | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 | ||
| ω (CaO)/% | / | / | / | 28.5-30.5 | 28.5-30.5 | 28.5-30.5 | 27.5-29.5 | 17.5-20.5 | 17.5-20.5 | ||
| ω (MgO) ≤/% | / | / | / | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | ||
| ω (R2O) ≤/% | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | ||
| ω (S) ≤/% | 0.1 | 0.1 | 0.1 | / | / | / | / | / | / | ||
| ω (Cl) ≤/% | 0.1 | 0.1 | 0.1 | / | / | / | / | / | / | ||
| Fineness | d50/μm | / | / | / | 11-4 | 8-11 | 6-9 | 10-13 | 5-8 | 5-8 | |
| -45μm ≤/% | / | / | / | 8.0 | 5.0 | 5.0 | 8.0 | 5.0 | 5.0 | ||
| Installation time | Initial setup time (min) | ≥45 | ≥60 | ≥90 | 120-180 | 30-90 | 180-240 | 150-210 | 30-90 | 90-150 | |
| Final setting time (min) | ≤6 | ≤6 | ≤6 | 150-240 | 90-180 | 240-330 | 210-300 | 90-180 | 270-360 | ||
| Strength (ISO) | Bending strength/MPa | 24h | 6.0 | 6.5 | 8.0 | 7.5-10.0 | 8.0-10.5 | 8.0-10.5 | 8.5-11.0 | 5.0-7.5 | 5.0-7.5 |
| 72h | 7.0 | 7.5 | 10.0 | 10.0-12.0 | 10.5-12.5 | 10.5-12.5 | 11.0-12.5 | 6.0-8.5 | 6.0-8.5 | ||
| Compressive strength/MPa | 24h | 45 | 55 | 72 | 40-50 | 45-55 | 45-55 | 50-60 | 30-40 | 30-40 | |
| 72h | 55 | 65 | 82 | 45-55 | 50-60 | 50-60 | 55-65 | 40-50 | 40-50 | ||
| 325M Остаток на сите, ≤/% | 15 | 12 | 8 | / | / | / | / | / | / | ||
| Specific surface area ≥/(㎡/kg) | 300 | 320 | 350 | / | / | / | / | / | / | ||
Characteristics of high alumina cement
| Chemical composition of high alumina cement | Characteristics of high alumina cement |
| Type of cement | Content of element oxides, % | ||||||
|---|---|---|---|---|---|---|---|
| СаО | Fe2O3 | SiO2 | MgO | SO3 | ТiO2 | Аl2О3 | |
| ВГЦ I | 32 | 1 | 3 | 1.5 | 2 | 0.05 | 60 |
| ВГЦ II | 28 | 1 | 1.5 | 1 | 2 | 0.05 | 70 |
| ВГЦ III | 18 | 0.5 | 0.5 | 0.5 | 0.5 | 0.05 | 80 |
| Физико-механические показатели | Значения для марки цемента | |||
|---|---|---|---|---|
| ВГЦ I | ВГЦ II | ВГЦ III | ||
| 35 | 25 | 35 | 25 | |
| Предел прочности при сжатии, МПа, не менее в возрасте: | ||||
| 1 сут. | - | - | - | - |
| 3 сут. | 35 | 25 | 35 | 25 |
| Тонкость помола: | ||||
| остаток на сите с сеткой №008, %, не более | 10 | 10 | 10 | 10 |
| удельная поверхность, м2/кг, не менее | 300 | 300 | 300 | 300 |
| Сроки схватывания: | ||||
| начало, мин., не ранее | 30 | 30 | 30 | 30 |
| конец, час, не позднее | 12 | 15 | 15 | 15 |
| Огнеупорность, oС, не менее | 1580 | 1670 | 1670 | 1750 |
Преимущства Высокоглиноземистых цементов ВГЦ
Refractoriness
High alumina cement has high fire resistance and the ability to maintain its strength and structure at high temperatures. This allows it to be used in the production of refractory products and materials.
High strength when heated
High alumina cement has high mechanical strength, even at extreme temperatures. It does not break down or deform under high thermal loads, making it ideal for use in fire-resistant structures.
Chemical inertness
High alumina cement is chemically inert to aggressive chemical environments such as acids and alkalis. This allows it to retain its properties even when interacting with corrosive environments.
Low thermal conductivity
High alumina cement has low thermal conductivity, which helps reduce heat transfer through refractory structures, providing better insulation and heat retention in high temperature systems.
Application
In recent years, High alumina cement has been widely used in ferrous and non-ferrous metallurgy as part of heat-resistant concretes and dry heat-resistant mixtures used in furnaces, boilers, and steel-pouring ladles. The use of such concretes and mixtures allows, due to their high thermal insulation properties, to save fuel and energy resources by reducing heat loss, and due to their high chemical resistance, it allows eliminating chemical interaction between the lining and molten metal. The high mechanical strength of these materials and their long service life reduce the cost of production, and the rapid gain in strength in the early stages of hardening reduces the repair time.
