Allmanna Svenska Elektriska Aktiebolaget

Asea Aktiebolag

Bengt Fredrikson

Karl-Erik Oberg

Kare Folgero

Materials of low electrical conductivity, such as minerals and metal compounds, are floated on a metal melt which is itself heated by a channel-type electric inductor, the heat from the melt transferring to the material. A pneumatic blast is injected into the melt so that the interface between it and the material is caused to dynamically undulate, promoting the heat exchange from the melt to the material. The blast can carry particles of additive or reactive agents.

Electric induction heating of materials of low electrical conductivity

Apparatus for melting, holding and tapping metals or metal alloys, in which solid material is melted down in a channel-type induction furnace, the melt then being transferred to a second channel-type induction furnace to be kept hot, possibly over-heated and stored, characterized in that the melting furnace is connected to the second furnace by way of a feeding channel and is located at a higher level than the second furnace and that the second furnace is in the form of a pressure furnace for pressure tapping through a spout. As a further characterizing feature, the tapping spout is provided with a tun dish in which sub-atmospheric pressures can be obtained to control the tapping through the spout.

Means for tapping

A metal-refining converter comprises an elongated vessel for containing a melt to be refined and which tilts so that it can be positioned upright or horizontal. This vessel has an upper end having a charging opening provided with a removable gas-tight cover and a lower end provided with a channel-type inductor, and the vessel has a closable tap hole in its side which is downward when the vessel is horizontal. The vessel is charged with the melt to be refined, via its charging opening. With the vessel upright, the vessel is provided with means for injecting refining material into the melt while it is heated by the inductor. After the refining period, the vessel is tilted to its horizontal position, the vessel having an internal contour such that a space is formed over the melt, the gas-tight cover being applied at that time. Non-oxidizing gas is injected into the vessel and with the inductor continuing to heat the melt, the latter is tapped via the tap hole. Control of the gas pressure within the vessel and of the electric power applied to the inductor, permits tapping to be effected, for example, via bottom pouring into ingot molds, at a constant rate and temperature. With these two normally varying factors under complete control, high-quality castings are obtained.

Growing community of inventors

Vasteras, Sweden

Bengt Fredrikson