PURPOSE: To prevent surely the bridging in a blast furnace by detecting the temp. in the front end of the blast tuyeres of the blast furnace, detecting the bridging in accordance with the detected values thereof and adjusting the blasting conditions to the tuyeres.
CONSTITUTION: 27 Pieces of tuyere thermometers 2 are respectively embedded in the front ends of respective tuyeres 1 at equal intervals in the circumferential direction of a blast furnace 8, and the detection signals of the tuyere temps. are converted to electric current signals with respective voltage/current converters 9. The signals are inputted to a calculator 7, by which the entire tuyere temp. is read at every one minute. Three pieces each of the adjacent tuyeres are divided to nine groups and the average tuyere temps. Ti (i=1W9) of the respective tuyere groups are calculated. The inversion Xi of the average value for recent 24hr of the temp. Ti and a standard deviation σi is calculated and the inversion (Xi+3σi) is calculated. The Ti and the inversion (Xi+3σi) are compared in each group, and when the Ti is higher than the inversion (Ti+3σi), the generation of bridging is discriminated and is displayed on a typewriter 10. The rate of the blast to be supplied to the tuyeres 1 through a hot stove 11 is adjusted with a fan 12.
KANBE MITSUO
KURODA TAKASHI
