High-Temperature Insulation: Heat Loss & Savings
Above ~300 °C, bare surfaces lose heat extremely fast — radiation dominates and loss climbs with the fourth power of temperature. High-temperature removable insulation (100 mm Wired mineral-wool here) cuts it by 96% and still holds the outer surface ≤50 °C.
Heat loss vs insulated — by surface temperature
| Surface temp | Bare loss | Insulated | Outer surface | Reduction |
|---|---|---|---|---|
| 300 °C | 2,800 W/m² | 201 W/m² | 40 °C | 92.8% |
| 400 °C | 3,800 W/m² | 316 W/m² | 52 °C | 91.7% |
| 500 °C | 4,800 W/m² | 453 W/m² | 65 °C | 90.6% |
| 600 °C | 5,800 W/m² | 612 W/m² | 81 °C | 89.4% |
Per-m² flat-surface flux, ASTM C680 / ISO 12241, 50 mm Lamella (≤220 °C) or 100 mm Wired mat (>220 °C), 20 °C ambient. Multiply by the bare area.
Worked examples (per year, 8,000 h, natural gas)
| Item | Heat saved | Energy/yr | CO₂/yr | € saved/yr |
|---|---|---|---|---|
| 1 m² of 450 °c surface (1.0 m², 450 °C) | 3.9 kW | 37 MWh | 7.5 t | €2,139 |
| 1 m² of 600 °c surface (1.0 m², 600 °C) | 5.2 kW | 49 MWh | 9.9 t | €2,832 |
FAQ
How much heat does a bare high-temperature lose?
At 20 °C ambient (ASTM C680): 1 m² of 450 °C surface (~1.0 m², 450 °C) loses about 3.9 kW; 1 m² of 600 °C surface (~1.0 m², 600 °C) about 5.2 kW. Insulating 1 m² of 450 °C surface saves ≈37 MWh and ≈7.5 t CO₂ per year (8,000 h).
Can you insulate superheater lines and similar?
Yes. High-temperature equipment must be inspected for hot spots and expansion. Removable high-temp jackets allow that while covering the surface. Inzonex covers superheater lines, furnace doors, exhausts, kilns and high-pressure steam fittings. The outer surface drops to a touch-safe ≤45 °C and the part stays serviceable.
How much does high-temperature insulation save?
Each item saves up to 96% of its bare loss. 1 m² of 450 °c surface at 450 °C saves ≈2,139 €/yr of energy (≈37 MWh, ≈7.5 t CO₂) at typical gas prices; payback is usually under two years.
What insulation thickness is used?
Up to 220 °C surface: 50 mm mineral-wool (Lamella); above 220 °C: 100 mm (Wired mat), because conductivity rises with temperature. Both keep the outer surface ≤45 °C.