METHOD FOR CONVERTING AND REUTILIZING WASTE GAS FROM CARBURIZATION HEAT TREATING FURNACE

摘要

PURPOSE:To reutilize the waste gas from a carburizing furnace with excellent utilizing efficiency by heating said gas to convert the same to the gas contg. extremely little CH4 ans supplying such gas as a carburizing gas to the carburizing furnace. CONSTITUTION:A necessary treating gas is supplied through an introducing pipe 2 from the 1st converting system 6 into a heating furnace 1 for curburization in the stage of subjecting mechanical parts such as gears to gas carburization and forming a carburized layer on the surface. An introducing pipe 3 for reutilizing waste gas is opened to actuate a circuit 18 for reutilizing the waste gas at the point of the time when the gaseous pressure in the furnace 1 stabilizes. The waste gas is sucked from an evacuating pipe 15 and is pressurized by a compressor 17 provided to the pipe 3, then the waste gas is heated to 800-1,100 deg.C in a heating furnace 11 to decompose the CH4 in the waste gas by CO2. Such gas is supplied to the furnace 1. The valve 4 of the 1st converting section is closed in this case and the fresh treating gas which is deficient is replenished by opening the valve 5 of the 2nd converting section 7. The carburization treatment is economically accomplished by utilizing the waste gas and using less fresh gas.