| 摘要 |
<p>1291363 Induction furnaces ALLMANNA SVENSKA ELEKTRISKA AB 19 Feb 1970 [20 Feb 1969] 7966/70 Heading H5H [Also in Division C7] Deposits, e.g. oxides, slag in the channels of a channel type induction furnace having at least two side channels, e.g. 29, 30, 31 leading from the hearth and joined at the ends remote from the hearth by a bottom channel 28 are prevented by the incorporation of at least one gas blowing nozzle, e.g 25, 26, 27, in the bottom channel in the region where at least one side channel joins the bottom channel. By suitably regulating the gas flow to the various side channels, e.g. by making the quantity of gas flowing through the porous plugs of the gas nozzles different, one way bath movement may be obtained. Thus, if a smaller quantity of gas is blown to the centre channel 31 than side channels 29, 30 the one way circulation is in the direction of arrows 36, whereas if more gas is blown into the side channels 29, 30 than centre channel 31, a one way circulation is obtained in the reverse sense. The channels may be curved (Fig. 2, not shown). The furnace is especially designed for aluminium, magnesium and their alloys. Inert gas (nitrogen or argon) or active gas, e.g. chlorine may be introduced during refining and degassing operations. The gas bubbles are said to be smaller than those obtained with a conventional gas lance so that the particles which would be deposited in the channels are carried to the hearth and hydrogen purification is more effective. More than three channels may be provided.</p> |
