Appendices
Appendix 5.3: Technical and energy usage characteristics of electric melting furnaces
Cast iron: Channel
|
Applied power |
Holding power |
Coil efficiency |
Melting temperature |
Typical energy usage |
Melting require- ments |
Theoretical melting energy |
| KW | KW | % | °C (°F) | kWh/t | kWh/t* | kWh/t** |
| 1100–1500 | 250–350 | 92–95 |
1482–1510 (2700–2750) |
661–1213 | – | – |
Cast iron: Main frequency
| Applied power | Holding power |
Coil efficiency |
Melting temperature |
Typical energy usage |
Melting require- ments |
Theoretical melting energy |
| KW | KW | % | °C (°F) | kWh/t | kWh/t* | kWh/t** |
| 300–5500 | 40–220 | 60–78 |
1455–1537 (2650–2800) |
573–882 | 550–595 | 374–398 |
Cast iron: Medium frequency
| Applied power | Holding power |
Coil efficiency |
Melting temperature |
Typical energy usage |
Melting require- ments |
Theoretical melting energy |
| KW | KW | % | °C (°F) | kWh/t | kWh/t* | kWh/t** |
| 425–3500 | – | 77–83 |
1455–1566 (2650–2850) |
617–926 | 573–584 | – |
Steels: Steel – arc furnace
| Applied power | Holding power |
Coil efficiency |
Melting temperature |
Typical energy usage |
Melting require- ments |
Theoretical melting energy |
| KW | KW | % | °C (°F) | kWh/t | kWh/t* | kWh/t** |
| 1000–1800 | – | – |
1593–1649 (2900–3000) |
728–1075 | – | – |
Steels: Stainless – medium frequency
| Applied power | Holding power |
Coil efficiency |
Melting temperature |
Typical energy usage |
Melting require- ments |
Theoretical melting energy |
| KW | KW | % | °C (°F) | kWh/t | kWh/t* | kWh/t** |
| 250–1050 | 40 | 80–83 |
1621–1705 (2950–3100) |
728–2205 | 628 | 383–406 |
Copper: Channel
| Applied power | Holding power |
Coil efficiency |
Melting temperature |
Typical energy usage |
Melting require- ments |
Theoretical melting energy |
| KW | KW | % | °C (°F) | kWh/t | kWh/t* | kWh/t** |
| 200–450 | 40–120 | 85–93 |
1177–1204 (2150–2200) |
276–529 | 276–342 | 196–204 |
Aluminum: Medium frequency
| Applied power | Holding power |
Coil efficiency |
Melting temperature |
Typical energy usage |
Melting require- ments |
Theoretical melting energy |
| KW | KW | % | °C (°F) | kWh/t | kWh/t* | kWh/t** |
| 1500–1600 | 200–260 | 61–72 |
771 (1420) |
705–827 | 540–551 | 327 |
Adapted from works of L.V. Whiting, using data from a joint CANMET and Ontario Hydro study of 25 foundries in Ontario (1991–1993).
Notes : 1 t (tonne) = 1.10233113 ton (short); 1 ton = 0.90716843 t
*Melting, and up to temperature without holding
**Theoretical melting energy refers to the temperature specified