Alumina ceramic tube
We mainly produce alumina tubes, rods and various industrial ceramic parts, which are mainly used in thermalcouple temperature, liquid steel continous temperature, various industrial furnace(containing vacuum furnace, carburizing furnace, wire furnace, atmosphere furnace etc), especially widely used in petrochemical, spinning, electric, instrumentation, mechanical workout, military project etc industry.
| Main performance index | |||||
| Serial number | performance index | Measuring unit | High purity alumina | Alumina | High alumina |
| 1 | Al2O3 | % | 99.7 | 99.3 | 85 |
| 2 | SiO2 | % | less than0.1 | — | — |
| 3 | Density | g/cm3 | 3.95 | 3.88 | 3.2 |
| 4 | Wter absorption | % | 0 | 0.01 | 0.2 |
| 5 | Cld compressive strength | MPa | 450 | 350 | 200 |
| 6 | 20 degree Celsius leak rates | Torr/L.sec | less than10-11 | less than10-11 | less than10-11 |
| 7 | Twisting in high temperature | mm |
1700 degree
Celsius 0.2
allowance
|
1600 degree
Celsius 0.2
allowance
|
1400 degree
Celsius 0.2
allowance
|
| 8 | Bonding in high temperature |
1700 degree
Celsius
non-caked
|
1600 degree
Celsius
non-caked
|
1400 degree
Celsius
non-caked
|
|
| 9 | 20—1000 degree Celsius coefficient of |
mm.10-6/degree
Celsius.m
|
8.6 | 8.2 | 8.2 |
| thermal expansion | |||||
| 10 | Thermal conductivity | W/m.k | 25 | 25 | 25 |
| 11 | Electric insulation strength | KV/mm | 20 | 20 | 15 |
| 12 | 20 degree Celsius direct current | Ohm/cm | 1014 | 1014 | 1014 |
| insulating resistance | |||||
| 13 | High-temperature |
1000 degree
Celsius MΩ
|
≥0.08 | ≥0.08 | ≥0.08 |
| insulation resistance |
1300 degree
Celsius MΩ
|
≥0.02 | ≥0.02 | ≥0.02 | |
| 14 | Thermal shock resistance |
1550 degree
Celsius 6
times not
racked
|
1550 degree
Celsius 6
times not
cracked
|
1300 degree
Celsius 3
times not
cracked
|
|
| 15 | Maximum service temperature | degree Celsius | 1900 | 1800 | |