Extending campaign life: what really helps on industrial furnaces

Two identical furnaces with identical linings can last for very different lengths of time. The difference rarely lies in the material alone, but in a handful of decisions.

Four levers that noticeably extend service life

• Material selection according to load zone: at the bath and melt line, non-wetting materials are used that prevent aluminium infiltration and corundum formation — a main cause of early wear on aluminium furnaces.
• Controlled heat-up curve: defined holding stages instead of a rapid ramp-up avoid cracks and spalling.
• Precisely dimensioned expansion joints: too narrow leads to spalling, too wide to infiltration — a few millimetres decide months of service life.
• Early detection by thermography: measure the shell temperature as a trend and carry out spot repairs before a hotspot becomes an unplanned shutdown.