Perlite Insulation
Thermal conductivity - k-values - vs. temperature.
Perlite is a type of volcanic glass that expands four to twenty times its original volume and becomes porous when heated. Perlite is suitable in high temperature applications.
Thermal conductivity vs. temperature are indicated in the charts below:
- tC = 5/9 (tF - 32)
- 1 W/(m K) = 6.935 (Btu in)/(h ft² °F)
- Refractive Index : 1.5
- Free Moisture : maximum 0.5%
- pH (of water slurry) : 6.5 - 8.0
- Specific Gravity : 2.2 - 2.4
- Bulk Density (loose weight) : depending on the expansion process but usually in the 2-25 lb/ft3 range (32-400 kg/m3)
- Softening Point : 1600 - 2000 oF (871 - 1093 oC)
- Fusion Point : 2300 - 2450 oF (1260 - 1343 oC)
- Specific Heat : 0.2 Btu/lboF (387 J/kgK)