A dosing furnace is not a melting furnace: refractory lining in holding operation

A dosing furnace is not a small melting furnace — and must not be treated as one in refractory terms either. The reason lies in the loading: a holding and dosing furnace does not melt, it keeps aluminium liquid at around 700–750 °C for weeks on end. Instead of thermal shock from charging, permanent contact with the melt dominates — with infiltration, corundum growth and targeted attack at the level of the bath line.

What matters when lining a dosing furnace

• Non-wetting, corundum-resistant materials: the melt should not take to the lining — that determines cleaning intervals and service life.
• A monolithic, dense surface instead of many joints — every joint is an entry point for metal.
• Dimensional accuracy: dosing accuracy depends directly on the geometry of the bath, riser tube and dosing chamber. Millimetres count here.
• Controlled first heat-up with holding stages so that bound water escapes safely before the furnace goes into production.