The shell temperature needs to be maintained below around 350 °C to protect the steel from damage, and continuous infrared scanners are used to give early warning of "hot-spots" indicative of refractory failure.
外壳温度必须保持在低于350℃左右，以保护钢铁免受损害，并连续红外扫描仪是用来给的“热点”表示耐火故障预警。