The characteristic erosion of a blast furnace hearth in which hot metal flow, especially around the tapholes and at the junction of the hearth wall and bottom, cuts a deep notch in the carbon lining. Seen in section, the worn profile looks like the outline of an elephant's foot. Operators track it with hearth thermocouples and fight it with titanium additions that build a protective layer and with careful casting practice.
Hearth thermocouples at the 5 o'clock taphole are climbing, the elephant foot is getting deeper there.
Also heard as
- elephant's foot
- elephant foot erosion
Related terms
Breakout
Escape of molten metal or slag through a failed lining and shell, the most dangerous refractory failure.
Taphole
Opening through a furnace wall or bottom through which molten metal and slag are drained.
Salamander
Pool or mass of iron left in a blast furnace hearth below the taphole, tapped or dug out at a reline.