Liquid metal or slag burning through the working and safety linings and out of the shell of a ladle, blast furnace hearth, furnace or runner. Breakouts cause fires, explosions when metal meets water, and long outages. They are prevented with lining life limits, thermocouples and shell scanning, and with strict tear-out inspection. In continuous casting the same word means the steel shell rupturing below the mold.
Ladle 9 had a breakout at the slag line, metal on the floor of the bay, nobody hurt, we're pulling every ladle on that campaign.
Most breakouts gave warnings first: a creeping shell temperature, a lining past its heat limit or metal found in the safety lining.
Also heard as
- burn-through
- run-out
- bleed-out
Related terms
Safety lining
Refractory layer behind the working lining that holds molten metal back if the working lining fails.
Hot spot
Area of a vessel or kiln shell running hotter than normal because the lining behind it is thin or gone.
Red spot
Shell area glowing visibly red from lining loss, the signal to take a kiln or vessel out of service.
Elephant foot
Blast furnace hearth wear profile where the wall-to-floor corner erodes into the shape of an elephant's foot.