Development of new technique for continuous molten steel temperature measurement

In the production of steel in a smelting furnace such as a converter, to measure molten steel temperature is extremely important to both process control and metallurgical quality. Generally, sublance method is only utilized for direct measurement of the steel temperature. A disposable thermocouple probe attached at the tip of the sublance is intermittently inserted the steel. Nippon Steel developed a new continuous temperature measurement technique using 2-dimensional radiation thermometry. The molten steel is observed through a tuyere nozzle at the bottom of the furnace. Experiments were carried out on a laboratory steel bath, a stainless steel converter AOD and a scrap melting furnace. Efficiency of this continuous thermometry was clarified.