Breakout
Breakout turns up in 2 fields: refractories, PCBs. Here is what it means to the people in each one.
Breakout in refractories
Escape of molten metal or slag through a failed lining and shell, the most dangerous refractory failure.
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."
Breakout in PCBs
Drilled hole wandering past the edge of its pad, or the routing that escapes signals from a dense part.
Breakout has two meanings on a PCB. In fabrication it is a drilled hole so far off center that it cuts through the edge of its pad, leaving no annular ring on one side; inspection standards set how much is acceptable for each class. In layout it is the routing that brings signals out from under a dense component such as a BGA to open board area, usually through dog-bone fanouts and vias, also called escape routing.
"BGA breakout took six layers, but the real problem is drill breakout on the 8 mil vias at the panel corner."