VIM: The whole induction furnace body is located inside melting chamber, water cooled melting chamber consists of two parts ,fixed and movable chambers, the movable chamber is driven by AC driver long the rails to make the melting chamber close and open. The interface between fixed and movable parts uses designs of inclined or vertical plane (depending on the furnace capacity), this design expedites and facilitates the furnace operations like charging, deslagging, and maintenance under air atmosphere. Furnace body can be easily detached to change with the one of different capacity to meet the needs of special steel production with small quantity and large varieties.