Refractory materials in cupola furnaces
- Good processing characteristics for relining and repair work
- suitable for drying and heating processes in the shortest time mwith hot gases,
- thermal fatigue resistance especially with pre-blowing and melting down due to pronounced flame formation up to the ring chamber,
- chemical resistance especially to carbon monoxide; at the start of the melting process, carbon monoxide and carbon dioxide are produced continuously according to the Boudouard balance, having intensive contact with the refractory material and being chemically reactive.
- Sufficient mechanical load capacity due to the input material while moving through the various furnace zones,
- chemical resistance to the slag that forms, especially with high slag quantities,
- good breakout behaviour for relief of personnel,
- no use of masses containing pitch or chrome.
Cold blast cupola furnace
Structure of the refractory material in the shaft with
two lining layers:
Sprayed concrete high in alumina with low cement content.
Mix of quartz and clay (classic clay sands)
Life of the wear lining: Usually only one day.
Example for the consumption of refractory material:
For the shaft of a cold blast cupola furnace with a daily melting output of 80 to 120 t of liquid iron, approx. 2.5 t spraying mix is needed for daily repairs; i.e. approx. 20–30 kg of refractory material per ton of liquid metal.
Labour per day: approx. 16 person hours
Material and labour costs for the refractory lining:
15–25 EUR/t liquid metal.
Consumption of refractory material with hot blast cupola furnace (cast lining):
0.4–1.2 kg of refractory material per ton of liquid metal.