摘要:
A VAR process is conducted in an apparatus characterized by a crucible wall that provides a stable shelf anchor. The VAR apparatus includes a furnace chamber, a consumable electrode formed of a material to be remelted within the furnace chamber and a crucible within the furnace chamber. The crucible has a wall that forms a vessel to collect melt material from the consumable electrode. At least part of the wall is textured to provide area for mechanical stabilization of the shelf as the underside of the shelf melts and the upperside of the shelf forms. In a vacuum arc remelting process, a consumable electrode is loaded into a furnace chamber above a cooled crucible having a textured wall that forms a vessel to collect melt material from the consumable electrode. The process includes striking a direct electric current between the electrode and a bottom of the crucible to cause melting of material from a tip of the electrode. Melt material is collected from the tip in the crucible. The melt material is cooled to form an ingot characterized by a shelf of solidified material forming adjacent the textured section of the crucible wall in advance of a lower boundary of solidifying material.
摘要:
An electroslag refining apparatus includes upper and lower integral crucibles, with the lower crucible having a drain. In situ hot start is effected by depositing in the lower crucible a pre-refined starter. The starter is melted in the lower crucible to form a starter pool, and slag is deposited atop the starter pool for being melted thereby to develop a slag pool thereatop. An ingot electrode is lowered through the upper crucible to immerse a tip thereof into the slag pool. The electrode is powered to effect resistance heating of the slag pool to melt the electrode tip. The slag and starter pools are increased in volume into the upper crucible, with the drain then being opened to effect steady state operation.
摘要:
The flowrate of a stream discharged from a drain in a vessel is measured by imaging the stream, measuring a diameter of the stream image, and calculating the flowrate based on the measured diameter. A video camera may be aimed below the drain for imaging the stream. A computer is joined to the camera for measuring the diameter of the stream and calculating a corresponding flowrate therefor. Either the pressure head above the drain or the profile of the stream below the drain may be used in calculating the discharge stream flowrate
摘要:
A system for controlling the flow rate of the stream from an electroslag refining apparatus is taught. The system includes the introduction of unrefined metal into an electroslag refining process in which the unrefined metal is first melted at the upper surface of the refining slag. The molten metal is refined as it passes through the molten slag. The refined metal is collected in a cold hearth apparatus having a skull of refined metal formed on the surface of the cold hearth for protecting the cold hearth from the leaching action of the refined molten metal. A cold finger bottom pour spout is formed at the bottom of the cold hearth to permit dispensing of molten refined metal from the cold hearth. The flow rate of molten metal through the cold finger apparatus is controlled by coordinating, among other parameters: the rate of melting of the unrefined metal; the hydrostatic head of molten metal and slag above the bottom pour cold finger orifice; the rate of induction heat supplied to the metal within the cold finger apparatus; the rate of heat removal from the metal within the cold finger apparatus through the cold finger apparatus itself and through adjacent gas cooling means; and by applying electromagnetic force to selectively speed up, slow down and/or interrupt the flow of metal through the cold finger apparatus via an electromagnetic orifice, preferably utilizing a processor, such as a computer.
摘要:
A method and spray forming system for effectively spraying the inner diameters of intricate objects and makes inner diameter spray forming practical for articles that have various and complicated inner geometries. The spray forming system can include at least one of a rotating mandrel and preform, and atomizer, which is fed with liquid metal, to form a spray. The atomizer is positioned with respect to inner walls of at least one of the rotating mandrel and preform to accurately and fully spray form an inner diameter of an article, even if the article has complicated and irregular inner surfaces.
摘要:
A casting system and method for producing a metal casting is provided. The metal casting can comprise a fine-grain, homogeneous microstructure that is essentially oxide- and sulfide-free, segregation defect free, and essentially free of voids caused by air entrapped during solidification of the metal from a liquidus state to a solid state. The casting system can comprise an electroslag refining system; a nucleated casting system; and a cooling system that cools the metal casting so as to cool a liquidus portion of the metal casting. The metal casting is cooled in a manner sufficient to provide a microstructure that comprises a fine-grain, homogeneous microstructure that is essentially oxide- and sulfide-free, segregation defect free, and essentially free of voids caused by air entrapped during solidification from a liquidus state to a solid state.
摘要:
A consumable electrode feed system for a refining system provides consumable electrodes to a refining system. The consumable electrode feed system comprises a side feed device that feeds consumable electrodes to a refining system in a first direction; a refining feed device that feeds consumable electrodes to a refining system in a second direction, in which the second direction being generally orthogonal to the first direction; and a connection system for connecting fed consumable electrodes to each other. The consumable electrode feed system allows for a predetermined amount of a consumable electrode to be refined in the refining system, and can position another consumable electrode above a previously fed consumable electrode. The connecting system then can connect a fed consumable electrode to a previously fed consumable electrode thus avoiding refining operation.
摘要:
In a method and apparatus for the electroslag refining of metal, the method includes providing a refining vessel to contain an electroslag refining layer floating on a layer of molten refined metal. The refining vessel representing an upper part of a cooled mould comprises a plurality of superimposed sleeves which are electrically insulated from one another. The top sleeve, being the refining vessel, is substantially a non-consumable electrode and has a current lead electrically insulated from the sleeve. The molten electroslag layer is heated by a refining current which is passed from a power source through the mould and slag layer to the metal pool. An unrefined metal is lowered into the vessel into contact with the molten electroslag layer such that its surface is melted and overheated at the point of contact with the slag such that droplets of the metal are formed and these droplets pass down through the slag and are collected in a pool of molten refined metal beneath the slag.
摘要:
A method for controlling electromagnetic flux concentration in a discharge guide tube for a metal refining apparatus is provided. The discharge guide tube comprises a base plate, an extension, a central orifice that extends through the extension from a source of liquid metal to an outlet in the discharge guide tube for directing a stream of metal therethrough, and an interior discharge guide tube flux concentration configuration; an induction heater system that generates an electromagnetic field in the discharge guide tube, the induction heater system being disposed on the extension with a gap defined therebetween, the induction heater system and the discharge guide tube being capable of relative vertical movement and subsequent positions with respect to each other with the gap being essentially constant. The method for providing electromagnetic flux concentration comprises providing current to the induction heater system; generating an electromagnetic field resulting from the step of providing current; and directing an electromagnetic flux to the central orifice at locations defined by the interior discharge guide tube. The step of generating an electromagnetic flux also generates heat and the step of generating heat provides a control of the flow of the stream of metal in its liquidus condition. The electromagnetic field is applied at a substantially constant level regardless of the relative vertical movement and subsequent positions between the induction heater system and the discharge guide tube.
摘要:
A system and method of electroslag refining of metal is taught. The system and method includes the introduction of unrefined metal into an electroslag refining process in which the unrefined metal is first melted at the upper surface of the refining slag. The molten metal is refined as it passes through the molten slag. The refined metal is collected in a cold hearth apparatus having a skull of refined metal formed on the surface of the cold hearth for protecting the cold hearth from the leaching action of the refined molten metal. A cold finger bottom pour spout is formed at the bottom of the cold hearth to permit dispensing of molten refined metal from the cold hearth. The dimensions of the cold finger apparatus pour spout are controlled by positioning a retaining means around the outer surface of the pour spout thereby controlling the flow rate of molten metal through the cold finger apparatus.