Typical application
Mainly used for glass contact, as tankwall for melter and glass line areas, for insulation glass furnaces.
WOOL 70 is made of grains from a unique manufacturing process, the very specific chemical and crystallographic structure provides best corrosion resistance with several others benefits such as :
- smooth corrosion profile,
- lower joint corrosion thru better joint closure after heat-up,
- good electrical resistivity,
For crown application, refer to ZIRCHROM HC.
For electrodes blocks application, refer to ZIRCHROM HER.
WOOL 70 can also be used in combination of WOOL 50 in a DUO format.
Chemical and physical properties
Microstructure
Image
Typical chemical composition
Typical crystallographic analysis
Main phase:
- Cr2O3-Al2O3 solid solution
- monoclinic zirconia
Physical characteristics
| Description | International standards | British standards |
|---|---|---|
| Cold crushing strength | 160Mpa | 23,200psi |
| Refractoriness under load 0.2 MPa T0.5% | 1,720°C | 3,130°F |
| Coefficient of thermal expansion | 8.5 10-6/°C | 4.7 10-6/°F |
| Thermal conductivity at 1,000°C | 2.6W/m.K | 1.5 BTU/h.ft.°F |
| Thermal shock resistance | medium | medium |
| Porosity | 13% | 13% |
| Typical bulk density | 3.7g/cm3 | 230 pcf |
Expansion curve
Thermal conductivity curve
Storage
Specifically designed for insulation glass furnaces, both electrical, gas- and oxygas-fired.