OPERATION OF HOT STOVE

PROBLEM TO BE SOLVED: To control the furnace change of hot stoves and to improve the operational efficiency by fetching a pressure signal in a hot blast main tube from plural sets of hot stoves to a blast furnace, a pressure signal in the hot stove and a control opening/closing signal of a valve into an arithmetic processor and comparison-calculating with presetting condition. SOLUTION: The pressure sensor 33 is disposed in the hot blast main tube 13 for supplying the hot blast from the hot stoves 3-5 arranged in plural sets to the blast furnace 2. Further, the pressure sensor 30-32 is disposed in each hot stove 3-5. Furthermore, limit switches for observing the opening/closing condition are disposed in blast valves and filling valves 2a-2f, gas shut-off valves 7a-7c, exhaust blasting valves 8a-8c, flue valves 9a-9c and hot blast valves 11a-11c arranged in each hot stove 3-5. The pressure signals from these pressure sensors and the opening/closing signal from the limit switch, are fetched into the arithmetic processor 34 to execute the comparison-calculation. In the case that this calculated result equals to the presetting condition, the furnace change of the hot stoves is executed. In this way, the combustion time of the hot stove is extended by quickening the times of exhausting pressure and filling pressure.