EXHAUST-GAS TREATMENT SYSTEM OF SEALED-TYPE CONVERTER

摘要

An exhaust-gas treatment system of a sealed-type converter has a hood (3) for guiding converter exhaust gas and is provided with an emergency air admission valve device (14) communicatively connected to the hood (3) and comprising, essentially, a valve seat (17) communicating with a valve entrance for inflow of outside air, a valve body (19) normally in valve closed position against the valve seat to shut off air from entering the hood, and a valve body locking device (20, 21, 22) functioning to normally hold the valve body in locked state in the valve closed position and operating in an emergency to release the valve body, which thereupon separates away from the valve seat thereby to admit outside air into the hood to prevent occurrence of negative pressure in the hood.