Alumina Magnesia Castable
Alumina Magnesia Refractory Castable
Al-Mg refractory castables are prepared by fused magnesia, sintered magnesia, fused or sintered magnesia-alumina spinel, fused corundum, alumina powder, high alumina powder, etc. According to the quality of raw materials used, it can be divided into: common alumina-magnesia castables, common high alumina-spinel castables, alumina-magnesia oxide castables, alumina-spinel castables, corundum-spinel castables.
Ordinary Al-Mg castables are used for the overall lining of continuous casting ladles.
Ordinary high alumina-spinel castables are composed of high alumina bauxite aggregate with powder, bauxite and sintered spinel aggregate with powder. It is suitable for small and medium-sized continuous casting ladle overall lining, intermediate ladle permanent lining and electric furnace steel discharge chute lining etc.
The aggregate of alumina-magnesia castables is made of fused white corundum, or slab alumina, or fused high alumina corundum. It is generally used for the overall lining below the slag line of large ladle, and the use cycle is more than 1 times higher than that of common alumina-magnesia castables, and it can also be used as the lining of other high temperature furnaces, vessels and flow channels.
Alumina-spinel castables and corundum-spinel castables are mainly used for large ladle body lining and also for high power electric arc furnace cover lining.
Al-Mg refractory castables performance index
Item | AMC-70 | AMC-80 | AMC-85 | AMC-95 | |
(Al2O3+MgO)/% ≥ | 70 | 80 | 85 | 95 | |
Bulk density(110℃×24h after drying)/(g/cm³) ≥ | 2.6 | 2.8 | 2.85 | 2.95 | |
Normal temperature compressive strength, MPa | 110℃×24h after drying ≥ | 20 | |||
1000℃×3h after firing ≥ | 30 | ||||
Test temperature×3h after firing ≥ | 50(1500℃) | 50(1550℃) | 60(1550℃) | 60(1600℃) | |
Heating permanent line change, % | Test temperature×3h | -0.5~+1.5 | -0.5~+1.8 | -0.2~+1.8 | 0~+1.0 |
Alumina Magnesite Refractory Castable Features
1．Alumina magnesite castable have high strength.
2．Alumina magnesite castable have good volume stability.
3．Alumina magnesite castable have high temperature resistance.
4．Alumina magnesite castable have reasonable solidification time.
5．Alumina magnesite castable have better insulation performance.
6．Refractory alumina magnesite castable have thermal shock resistance.
7．Refractory alumina magnesite castable have good resistance to erosion.
Alumina Magnesite Refractory Castable Application
Aluminum Magnesium Castable Suitable for Ladle Lining
1.Castable alumina magnesite used in the inner lining has good overall performance and is not easy to crack and peel off.
2.Castable alumina magnesite used in the lining is used for a longer period of time, the safety factor is improved, and there will be no accidents such as redness and wearing a bag.
3.Castable alumina magnesite of convenient construction and short construction period.
4.Castable alumina magnesite the maintenance of ladle is convenient in the later stage, the maintenance cost is reduced.
Alumina Magnesite Refractory Castable Construction
1. Refractory Alumina Magnesite Castable Prepare for Work
(1) Ensure that the refractory castable is dry before use and has no agglomeration.
(2) Check if the pouring equipment is in good condition and it can operate normally.
(3) Whether the membrane is installed properly, whether the size of each part is reasonable, and whether the interval is even. The surface of the membrane is coated with a release agent to facilitate demolding after pouring.
(4) Prepare a suitable vibrating rod to ensure that the castable is vibrated and compact.
2.Alumina Magnesite Castable Mixing Work
1) Determine the amount of refractory castable based on the capacity of the mixer and the construction speed.
2) The amount of water added is generally about 4%-5% depending on the construction conditions.
3) Castable alumina magnesite is necessary to ensure good fluidity, prevent excessive dilution and excessive thickening, affect the use of castables.
4) The refractory castable after stirring needs to be used within 30 minutes. It is forbidden to use overtime and no fluidity.
3.Alumina Magnesite Castable Pouring Work
① When feeding, open the vibrating rod and vibrate while feeding. After the feeding is completed, shake it evenly to ensure that no bubbles are discharged.
② The bottom of the package is poured first, the bottom of the package is solidified before the mold is poured.
③ When pouring the wall, it should be uniformly fed continuously, and the entire wall should be filled in one time.
④ When using the vibrating rod, it should be moved slowly, not too fast or too slow.
4.Alumina Magnesite Castable Demolding and Maintenance
Alumina magnesite refractory castable can be demolded 16-24 hours after molding. The specific demoulding time is subject to the construction conditions and weather. The natural curing time after demolding shall not be less than 24 hours.
5.Alumina Magnesite Castable Baking
When baking, the temperature and baking time should not be too fast. For details, please consult the technician.
