| 摘要 |
1,152,886. Removing exhaust fumes in arc furnaces. SVENSKA FL KTFABRIKEN A.B. 31 May, 1967 [29 July, 1966], No. 25176/67. Heading F4X. [Also in Division G3] A device for adjusting the amount of flue gas exhausted from an electric arc melting furnace, wherein said furnace includes an arch 3 provided with lead-in openings 2 for electrodes 4 and an exhaust dust 6 extending to a gas cleaner 12 and a fan 17, comprises a smoke detecting device 5 (e.g. a photo-electric cell) located above the furnace arch which at a set value of the concentration of leakage flue gas at this point operates means to control the rate of flue gas withdrawal through the duct 6, the object being to minimize flue gas leakage through the electrode openings 2 and to maintain a flue gas layer below the furnace arch to protect the arch from radiation. Exhaust gas flow control by detector 5 may as shown be by regulation of a damper 9 in a fresh air intake 8. In other embodiments, the fresh air enters the exhaust duct 6 through a gap at the jointing sleeve 7, or control may be effected by changing the cross-section of the throat 14 of the Venturi tubes 13 of the gas cleaner, or by controlling the speed of the exhaust fan.
|
