I have seen furnaces that remain nearly brand‑new after twelve years of service, and others whose furnace chambers need replacement after only three years. The difference lies entirely in maintenance. Many factories run their furnaces around the clock yet do nothing except occasionally removing slag at the furnace opening. Naturally, such units will have short service lives.

Here are several easily‑overlooked maintenance points. First, retighten wiring terminals every month. Industrial furnaces undergo frequent start‑stop cycles and thermal expansion‑contraction caused by temperature swings. Loose terminals may trigger arcing and burn out heating elements. Production losses from just one‑day shutdown can exceed half‑a‑month’s labor expenses. Second, calibrate thermocouples every six months. Slow heating and inaccurate temperature readings in many furnaces stem not from failed heating elements, but aged thermocouples whose readings can deviate dozens of degrees from actual temperatures. Third, remove scale every week. Do not wait until it accumulates inside heating gaps. Conductive scale buildup may cause short‑circuit arcing and burn through the furnace’s refractory lining.

In addition, frequently inspect the furnace lining for damage or loose components. Never strike the furnace chamber violently with sledgehammers during cleaning. Refractory fibers and bricks are brittle; even one broken piece creates heat‑leakage points. Some customers regard maintenance as extra expense, yet it actually saves money. Small regular maintenance costs are far lower than losses caused by unexpected furnace breakdowns and production halts.