The alumina bubble produced by the company is a hollow spherulitic heat-inaulating meterial,which is made by electrofused method.It is noted for its light-weight,heat-resistance,close pore.It is an ideal filler for high-temperatuer furnaces and and excellent aggregate of light weight castable refractory.And it is an ideal heat-inaulating and energy-saving refractory in high temperatrue.


Items Unit Index
Chemical composition Al2O3 % 98.5min
SiO2 % 0.25max
Fe2O3 % 0.10max
Na2O % 0.40max
Refractoriness °C 1800min
Principal crystalline -- a -Al2O3
Packing density g/cm3 0.50~1.00
Particle size mm φ0.2~5

Light Weight Alumina Bubble Castable Refractory
Properties Brands KT-è½» GL-18C
Chemical composition(%) Al2O3 ≥95 ≥95
SiO2 ≤0.5 ≤0.5
max service temperature ( ° C ) 1800 1800
bulk density after burnt at 1500 ° C(g/cm3) 1.35-1.40 1.35-1.40
Linear changes after burnt at (1500°C�3h)(%) ±0.5 ±0.5
compressive / bending
strength ( MPa ) 110 ° C�24h ≥8 /≥3 ≥8/≥3
1100 ° C�3h ≥15/≥4 ≥15/≥4
1500 ° C�3h ≥20/≥6 ≥25/ ≥6
max particle size of bubbles(mm) 5 5

water content for construction (%): 9-12 9-12
thernel conductivity coefficient(w/m.k) 0.7-0.8 0.7-0.8

The alumina bubble is a hollow spherulitic heat-insulation matrials,which is made by electro fusing method.It is noted for its light-weight,heat-resistance,close pore.It is an ideal filler for high-temperature furnaces and an excellent aggregate of light weight castable refractory.



Physical Chemical Performance Index
SPEC Al2O3:99.00% MIN
Fe2O3:0.15% MAX
Na2O:0.40% MAX
SiO3:0.25% MAX
Size 0.1-5.0mm(or in mesh size)
Packing density 0.45-1.0g/cm3
Main crystalline a-Al2O3
Working temp. 1800° C
Packing 200KGS or 25KGS BAGS+BIG BAGS