抄録
Hot stoves using silica brick should either be cooled or hot-idled when the blast furnace is blown-out for relining or shut down for a long time. Noticing the thermal stress of the brick in a steady or a nonsteady state of temperature distribution and based on experimental and actual-furnace-operation data, the authors introduced the cooling rate suited for reducing the temperature difference between the inner side and the outer side of the silica brick in order to decrease the circumferential stress in the case of cooling. The authors also found the temperature range suited for reducing the radial stress and set the lower limit temperature of the brick at 450°C in the case of hot idling. Both these measures were applied to the hot stoves of the Kimitsu BF No. 3 achieving a large economic effect.
