GB668702A - Improvements in or relating to shaft furnaces, especially blast furnaces, provided with charging devices having charging hoppers - Google Patents

Abstract

668,702. Charging shaft furnaces. TESCH AKTIEBOLAGET, T. A. May 18, 1950 [June 1, 1949], No. 12497/50. Class 51 (ii). The bottom closure of the charging hopper of a shaft furnace comprises two conical valve members arranged one below the other, the lower valve being smaller than the opening in the charging hopper so that it can be raised above the opening together with the upper valve to allow material to be distributed to the central zone of the furnace, or lowered below the opening while the upper valve is raised above the opening to allow material to be distributed round the periphery of the furnace. Material from the main rotatable hopper C passes into a lower hopper B when the bell 3 is lowered. The bottom opening of the hopper B is closed by two conical bell valves 9, 25, the lower bell 25 being smaller than the opening and shaped so that it can fit inside the upper bell 9. When lowered into the position shown, the bell 25 co-operates with a frusto-conical distributer 14 mounted in the top of the furnace A so that by raising the upper bell 9 material is fed to the periphery of the furnace. To feed material to the central zone of the furnace, the bell 25 is raised to fit inside the upper bell 9, and the bells are raised together to allow material to fall through the centre of the distributer 14. The distributer 14 is provided with a cylindrical extension 18, and ribs 17 are provided on the bell 25 and distributer 14 to guide the material radially toward the wall of the furnace. A lining 15 protects the wall of the furnace. The upper bell 9 is made larger than the opening in the hopper B so that it provides a gas-tight seal for the furnace when lowered.