Appts. and method for inductively melting metal without crucible - involves placing metal to be melted on support within induction coil designed to maximise EMF to lower portion of metal

摘要

Metal is inductively melted without a container by locating a body of it on an annular support within an induction coil generating electromagnetic forces acting against the surface, those forces being stronger at the lower region of the body so that it retains its shape as it melts. Melting proceeds downwardly until all the metal is molten apart from a peripheral rim in contact with the support, the molten metal then flowing through the opening in the support, pref. into a casing mould. In a pref. embodiment the metal body is initially located only partially within the coil until that region of the metal is molten and at a predetermined temp.. The remainder of the body is then moved into the coil where it melts to effect discharge. Appts. includes an induction coil pref. having its uppermost turn wound in a direction opposite to that of the other turns to prevent levitation; also the coil is pref. mounted for axial movement relative to the metal body. The support member for the body is maintained at controlled temp. by flow of coolant. The appts. may include a mould or a rotating disc onto which the molten metal falls.