A gas ring is attached to an upper portion of a chamber side portion as a side wall of a chamber. The gas ring is formed by overlapping an upper ring and a lower ring. A gap between the upper ring and the lower ring provides a flow path for processing gas. A labyrinthine resisting unit is formed in the flow path. The mass of the lower ring having an inner wall surface is increased to increase heat capacity. The lower ring is attached to the chamber side portion to be in surface contact with the chamber side portion, so that thermal conductivity from the lower ring to the chamber side portion has a large value, and the amount of heat accumulated in the lower ring is reduced. An increase in temperature of the lower ring at thermal processing is thereby suppressed to prevent discoloration of the gas ring.

A vacuum arc remelt apparatus comprising a crucible having a wall, said wall having an interior and an exterior opposite said interior; an electrode within the crucible proximate the interior; an ingot within the crucible and below the electrode, wherein said ingot includes a crown and shelf; and a vibration source at the exterior of the crucible proximate the crown and shelf.

A sintering furnace may include a furnace chamber and a retort located within the furnace chamber that receives a part to be heated. The furnace may also include one or more heating elements positioned around the retort and a power controller including power modules connected in series. The power modules may be operably connected to the one or more heating elements and may provide a direct current (DC) power output. A controller may selectively control the power modules to supply power to the one or more heating elements.

A sintering furnace may include a furnace chamber and a retort located within the furnace chamber that receives a part to be heated. The furnace may also include one or more heating elements positioned around the retort and a power controller including power modules connected in series. The power modules may be operably connected to the one or more heating elements and may provide a direct current (DC) power output. A controller may selectively control the power modules to supply power to the one or more heating elements.

A conveyer system for vertically and helically conveying a workpiece includes a main bracket, on which interconnected heating furnace and cooling furnace are arranged in parallel. The heating furnace includes a 1.sup.st spiral supporting plate, a conveyer belt arranged on the 1.sup.st spiral supporting plate along the spiral direction and one or multiple gas inlet/inlets to fill protective gas into the heating furnace. The cooling furnace includes a 2.sup.nd spiral supporting plate, the conveyer belt extended from the heating furnace arranged on the 2.sup.nd spiral supporting plate along the spiral direction and one or multiple gas inlet/inlets to fill protective gas into the cooling furnace. A drive mechanism for a conveyer belt is installed on the main bracket. The conveyer belt runs through the heating furnace and cooling furnace and forms one loop via the drive mechanism.

A conveyer system for vertically and helically conveying a workpiece includes a main bracket, on which interconnected heating furnace and cooling furnace are arranged in parallel. The heating furnace includes a 1.sup.st spiral supporting plate, a conveyer belt arranged on the 1.sup.st spiral supporting plate along the spiral direction and one or multiple gas inlet/inlets to fill protective gas into the heating furnace. The cooling furnace includes a 2.sup.nd spiral supporting plate, the conveyer belt extended from the heating furnace arranged on the 2.sup.nd spiral supporting plate along the spiral direction and one or multiple gas inlet/inlets to fill protective gas into the cooling furnace. A drive mechanism for a conveyer belt is installed on the main bracket. The conveyer belt runs through the heating furnace and cooling furnace and forms one loop via the drive mechanism.

An induction furnace comprising a upper furnace vessel; an induction coil positioned below the upper furnace vessel; and a melt-containing vessel positioned inside the induction coil and communicably connected to the upper furnace vessel, wherein the positioning of the melt-containing vessel inside the induction coil defines a gap between an outside surface of the melt-containing vessel and an inside surface of the induction coil. A system for direct-chill casting comprising at least one an induction furnace; at least one in-line filter operable to remove impurities in molten metal; at least one gas source coupled to a feed port associated with the gas; and at least one device for solidifying metal by casting. A method of cooling an induction furnace comprising introducing a gas into a gap between an induction coil and a melt-containing vessel positioned inside the induction coil; and circulating the gas through the gap.

An induction furnace comprising a upper furnace vessel; an induction coil positioned below the upper furnace vessel; and a melt-containing vessel positioned inside the induction coil and communicably connected to the upper furnace vessel, wherein the positioning of the melt-containing vessel inside the induction coil defines a gap between an outside surface of the melt-containing vessel and an inside surface of the induction coil. A system for direct-chill casting comprising at least one an induction furnace; at least one in-line filter operable to remove impurities in molten metal; at least one gas source coupled to a feed port associated with the gas; and at least one device for solidifying metal by casting. A method of cooling an induction furnace comprising introducing a gas into a gap between an induction coil and a melt-containing vessel positioned inside the induction coil; and circulating the gas through the gap.

A furnace for a dental prosthesis or a partial dental prosthesis, in particular for dental ceramic, comprising a firing chamber which can be heated and in particular can also be evacuated, a control device for controlling the operation of the furnace on the basis of a firing program, which is based on a set of parameter values, and an operator control unit, which is assigned to the control device and is designed to display a representation of the firing program in the form of a firing process curve, wherein the operator control unit can be used in a simplified operating mode in which it displays together with the firing process curve at least one operator control area for adjusting a selected parameter value of the set of parameter values that relates to a prescribed program phase of the firing program, wherein the at least one operator control area is permanently arranged in the area of the displayed firing process curve that corresponds to the prescribed program phase.

A furnace for a dental prosthesis or a partial dental prosthesis, in particular for dental ceramic, comprising a firing chamber which can be heated and in particular can also be evacuated, a control device for controlling the operation of the furnace on the basis of a firing program, which is based on a set of parameter values, and an operator control unit, which is assigned to the control device and is designed to display a representation of the firing program in the form of a firing process curve, wherein the operator control unit can be used in a simplified operating mode in which it displays together with the firing process curve at least one operator control area for adjusting a selected parameter value of the set of parameter values that relates to a prescribed program phase of the firing program, wherein the at least one operator control area is permanently arranged in the area of the displayed firing process curve that corresponds to the prescribed program phase.