Typical Watt Densities Tool
A guide to watt density rating for heating elements, for a wide range of materials.
| Material Being Heated | Operating Temperature °C | Watt Density W/cm² |
|---|---|---|
| Alkali Cleaning Solution | 100 | 6.0 |
| Asphalt, Tar, etc | 90-250 | 1-1.5 |
| Caustic Soda (75%) | 80 | 4.0 |
| Degreasing Solutions (Vapour) | 135 | 3.0 |
| Heat Transfer Oils | 320 | 3.0 |
| Elements Cast into Aluminium | 400max | 8.0 |
| Elements Cast into Iron | 550max | 8.5 |
| Ethylene Glycol | 150 | 1.5 |
| Fatty Acids | 70 | 3.0 |
| Fuel Oil | 70 | 6.0 1.5 |
| Freon | 150 | 0.5 |
| Glycerine | 100 | 6.0 |
| Water | 100 | 15.0 |
| Kerosene/Paraffin | 150 | 0.5 |
| Linseed Oil | 70 | 8.0 |
| Molten Salt Bath | 400-500 | 4-5 |
| Mineral Oil | 100-200 | 2-3 |
| Oil Quench Bath | 200-300 | 3-4 |
| Propylene Glycol | 70 | 3.0 |
| Trichlorethylene | 70 | 3.0 |
| Vegetable Oils | 200 | 5-6 |
| Material Being Heated | Operating Temperature °F | Watt Density W/in² |
|---|---|---|
| Alkali Cleaning Solution | 212 | 38.85 |
| Asphalt, Tar, etc | 194-482 | 6.475-9.712 |
| Caustic Soda (75%) | 176 | 25.9 |
| Degreasing Solutions (Vapour) | 275 | 19.425 |
| Heat Transfer Oils | 608 | 19.425 |
| Elements Cast into Aluminium | 752max | 51.8 |
| Elements Cast into Iron | 1022max | 55.038 |
| Ethylene Glycol | 302 | 9.713 |
| Fatty Acids | 158 | 19.425 |
| Fuel Oil | 158 | 38.85 9.713 |
| Freon | 302 | 3.238 |
| Glycerine | 212 | 38.85 |
| Water | 212 | 97.125 |
| Kerosene/Paraffin | 302 | 3.238 |
| Linseed Oil | 158 | 51.8 |
| Molten Salt Bath | 752-932 | 25.9-32.375 |
| Mineral Oil | 212-392 | 12.95-19.425 |
| Oil Quench Bath | 392-572 | 19.425-25.9 |
| Propylene Glycol | 158 | 19.425 |
| Trichlorethylene | 158 | 19.425 |
| Vegetable Oils | 392 | 32.375-38.85 |