| 摘要 |
1290831 Refining steels LECTROMELT CORP 7 Jan 1970 [12 June 1969] 747/70 Heading C7D Molten ferrous alloy is introduced into the lower chamber of an apparatus comprising upper and lower chambers connected by a conduit, and is partially forced into the upper chamber by a combination of vacuum applied to the latter and pressure applied to the lower chamber. The metal in the upper chamber is then decarburized by addition of oxides of iron, nickel or chromium, or by gaseous oxygen, while it may also be heated. In one embodiment metal in ladle 11 is introduced into pit 10 which may be sealed by cover 17 and pressurized e.g. by nitrogen supplied through pipe 21. Vessel 27 mounted on the cover is provided with vacuum connection 30, hopper 60 for additions and induction coil 33. By intermittently reducing the pressure in the pit 10 the treated metal from the vacuum vessel may be mixed with the untreated metal remaining in the ladle. In addition to the hopper 60 for oxidizing additions a lance for oxygen may also be provided. |
