Abstract: Molten iron is cast into a mould through a filter located in the runner system of the mould using a filter comprising a body having a plurality of cells, at least some of the cells having their walls at least partially coated with a first layer of wax and a second layer of an inoculant, such as graphite, calcium silicide or ferrosilicon, for the iron.
Type:
Grant
Filed:
July 18, 1990
Date of Patent:
July 23, 1991
Assignee:
Foseco International Limited
Inventors:
Charles Fisher, Hugh Kind, James Devine, Michael J. Gough, Ian N. Delaney
Abstract: A metallurgical flux composition comprising calcium oxide, alumina, magnesium oxide and silica contains 22-35% by weight magnesium oxide and has a weight ratio of calcium oxide to magnesium oxide of from 0.6:1 to 2.5:1. The preferred composition contains 28-42% by weight calcium oxide, 13-21% by weight alumina, 22-35% by weight magnesium oxide and 3-8% by weight silica, preferably has a calcium oxide to magnesium oxide weight ratio of from 0.8:1 to 1.9:1 and preferably has a calcium oxide to silica weight ratio of from 6.0:1 to 7.5:1. The flux composition is particularly useful as a tundish cover in the continuous casting of steel.
Abstract: A filter for use in the filtration of molten metals comprises a ceramic foam having a gasket made from fibrous material surrounding its peripheral surface and a metallic foil, such as aluminum foil, fixed to the gasket, for example by means of an adhesive, around the outer peripheral surface of the gasket.
Type:
Grant
Filed:
June 28, 1990
Date of Patent:
April 2, 1991
Assignee:
Foseco International Limited
Inventors:
Hans-Peter Wahl, Rudolf Schlueter, Wolfgang P. Kaettlitz, Rolf Loos
Abstract: The invention relates to a means of purifying molten metal, particularly steel, by the removal of impurities/inclusions during continuous casting.The molten metal (3) is passed in a tundish (1) through a vertical array of baffles (8) that are spaced apart transversely across the tundish to provide restricted flow channels (12). The baffles (8) may be flat boards or tiles (9a, 9b) and are preferably used in contact with a weir (7) and dam (10), upstream and downstream respectively of the baffles.The speed and direction of flow of the molten metal can thereby be controlled and directed to give more effective dwell time in contact with a surface covering layer (11) of flux.
Type:
Grant
Filed:
December 5, 1989
Date of Patent:
February 26, 1991
Assignees:
Foseco International Limited, British Steel PLC
Inventors:
Neil J. Kegan, Ian Hitchens, Thomas Robertson, Paul A. Whitehouse
Abstract: A binder composition for producing articles of bonded particulate material such as foundry moulds or cores comprises an alkaline aqueous solution of a resol phenol-aldehyde resin and an oxyanion capable of forming a stable complex with the resin the amount of alkali present in the solution being sufficient to substantially prevent stable complex formation. Bonded articles are produced from mixtures of particulate material and the binder composition by passing carbon dioxide gas through the formed articles whereby the oxyanion forms a stable complex with the resin and the resin is cured. The oxyanion may be for example borate, stannate or aluminate.
Type:
Grant
Filed:
September 29, 1989
Date of Patent:
January 15, 1991
Assignee:
Foseco International Limited
Inventors:
Sidney A. Barker, Neil Baggett, John Stevenson, Raymond D. George, David R. De Courcy, Timothy Hammond, Martin Bradley
Abstract: A binder composition for producing articles of bonded particulate material such as foundry moulds or cones comprises an alkaline aqueous solution of a resol phenol-aldehyde resin and an oxyanion capable of forming a stable complex with the resin the amount of alkali present in the solution being sufficient to substantially prevent stable complex formation. Bonded articles are produced from mixtures of particulate material and the binder composition by passing carbon dioxide gas through the formed articles whereby the oxyanion forms a stable complex with the resin and the resin is cured. The oxyanion may be for example borate, stannate or aluminate.
Type:
Grant
Filed:
December 6, 1988
Date of Patent:
December 11, 1990
Assignee:
Foseco International Limited
Inventors:
Sidney A. Barker, Neil Baggett, John Stevenson, Raymond D. George, David R. De Courcy, Timothy Hammond, Martin Bradley
Abstract: This invention concerns thermocouples for the measurement of temperature of molten metal which have a bimetal junction located in a closed outer end of a length of quartz glass tube with the wire ends separated around a plug in the open end of the tube and connected to the compensating conductors of the thermocouple.
Abstract: A mould (61) for metal casting has a mould cavity (62) and a sprue (63) communicating directly with the mould cavity (62) and located in the sprue (63) a sleeve (64) of refractory material having a cellular ceramic filter (65) fixed therein. The mould, which has no running system apart from the sprue, may be a sand mould or a metal die for producing castings by gravity or low pressure diecasting. The cellular ceramic filter may be a honeycomb type of structure having cells which extend between two outer surfaces of the filter or a structure having interconnecting cells such as a ceramic foam.
Type:
Grant
Filed:
March 1, 1990
Date of Patent:
October 9, 1990
Assignee:
Foseco International Limited
Inventors:
David R. Butler, George Snow, Philip Sandford, Max G. Neu, Jean P. Villani, Alain Teyssedre, Roland Lenoir
Abstract: Pouring tubes for use between a ladle and tundish or tundish and mould in continuous casting operations are formed of an inner refractory tube (2) with an outer reinforcing fibrous mat (3) applied around the tube. The fibrous mat may be formed by a helically wound strip and may be impregnated with particulate refractory and optionally a binder to improve the strength and resistance of the composite tube. Metal support means may be attached near one end of the tube.
Abstract: A mould (61) for metal casting has a mould cavity (62) and a sprue (63) communicating directly with the mould cavity (62) and located in the sprue (63) a sleeve (64) of refractory material having a cellular ceramic filter (65) fixed therein. The mould, which has no running system apart from the sprue, may be a sand mould or a metal die for producing castings by gravity or low pressure diecasting. The cellular ceramic filter may be a honeycomb type of structure having cells which extend between two outer surfaces of the filter or a structure having interconnecting cells such as a ceramic foam.
Type:
Grant
Filed:
January 18, 1989
Date of Patent:
May 29, 1990
Assignee:
Foseco International Limited
Inventors:
David R. Butler, George Snow, Philip Sandford, Max G. Neu, Jean P. Villani, Alain Teyssedre, Roland Lenoir
Abstract: A mould for the production of a nodular or compacted graphite iron casting has parts comprising a treatment sprue, a runner, a slag trap, a filter chamber having an ingate and an outlet and having located therein a ceramic filter having an inlet and outlet, a casting cavity ingate, and a casting cavity, and the parts of the mould have a relationship one with another such that F2=0.8 F1 to 1.2 F1, F3=30% F4 - 100% F4, F4.gtoreq.4.5 F1, F5.gtoreq.1.3 F1, F6=2 F5 to 4 F5, F7.gtoreq.F5 and .ltoreq.F6, F8.gtoreq.F5 and .ltoreq.F6, F9=1.2 F1 to 3 F1, F10.gtoreq.
Abstract: An article of refractory holloware for use in a runner assembly for casting molten metals e.g. ferrous metals, has at least one inner surface adapted to increase the internal surface contact area of the article. The surface is so arranged as to effect at least two abrupt changes of direction of flow of molten metal flowing through the article. Use of the article minimizes the level of non-metallic inclusions in ingots and castings.
Abstract: A rotary device for dispersing gas in molten metal comprises a hollow shaft and a hollow rotor attached to the shaft, the rotor having a plurality of vanes extending from the shaft towards the periphery of the rotor and dividing the rotor into a plurality of compartments, each compartment having an inlet adjacent the shaft and an outlet adjacent the periphery of the rotor, and the rotor having means for passing gas from the discharge end of the shaft into the compartments, wherein the discharge end of the shaft opens into a manifold in the rotor and the inlets for the compartments are present in the wall of the manifold. When the device is rotated in molten metal contained in a vessel and gas is passed down the shaft, metal is drawn into the manifold and breaks up the gas stream emerging from the shaft into very small bubbles. The gas/metal dispersion flows into the compartments through the inlets and out through the peripheral outlets and the gas is dispersed through the whole body of molten metal.
Abstract: An elongate tubular porous ceramic filter for use in the filtration of fluid media, e.g. the filtration of particulate matter from hot gases, is formed from a plurality of shorter tubular portions (10, 11, 12, 13, 14, 15, 20, 21) adhered together by a high-temperature adhesive at bonding points (30, 31) to provide long filter tubes.
Type:
Grant
Filed:
November 10, 1988
Date of Patent:
January 16, 1990
Assignee:
Foseco International Limited
Inventors:
Wolfram Keidel, Wilhelm Barlag, Rolf Loos
Abstract: An expendable substrate which in use contacts molten metal, for example a foundry mould or core or ladle lining, is coated with a coherent layer of refractory particles by tribo-electrically charging refractory particles coated with an organic binder, the coated particles having an electrical resistivity of at least 10.sup.10 ohm. cm. at 10kv, earthing the substate and bringing the charged particles into contact with the earthed substrate. Suitable binders are thermoplastic resins, thermosetting resins and waxes and the quantity of binder in the binder coated particles is usually less than 10% by weight.
Abstract: A rotary device for dispersing gas in molten metal comprises a hollow shaft and a hollow rotor attached to the shaft, the rotor having a plurality of vanes extending from the shaft towards the periphery of the rotor and dividing the rotor into a plurality of compartments, each compartment having an inlet adjacent the shaft and an outlet adjacent the periphery of the rotor, and the rotor having means for passing gas from the discharge end of the shaft into the compartments, wherein the discharge end of the shaft opens into a manifold in the rotor and the inlets for the compartments are present in the wall of the manifold. When the device is rotated in molten metal contained in a vessel and gas is passed down the shaft, metal is drawn into the manifold and breaks up the gas stream emerging from the shaft into very small bubbles. The gas/metal dispersion flows into the compartments through the inlets and out through the peripheral outlets and the gas is dispersed through the whole body of molten metal.
Abstract: Metallurgical treatment agents for molten ferrous metals e.g. iron and steel and suitable for e.g. desulphurizing molten iron and steel comprise particulate magnesium coated with a first coating of a hydrophobic compound and a second coating of a particulate refractory material. The coated magnesium possesses improved flowability and is less prone to premature reaction when subjected to a high temperatures. The hydrophobic compound provides the magnesium with enhanced protection against hydration than may be obtained by a refractory coating alone.
Abstract: A sampler compries a mould (2) held in a slot (8) at the end of a tube (6) having a cardboard inner wall and an outer protective coating (7), the end of the tube (6) being received in the socket (10) of a body (9), a bore (11) extending between the socket (10) and the outside of the body (9) so that molten metal may reach the mould.
Abstract: A metal casing pattern of expanded thermoplastics material such as polystyrene or polymethyl methacrylate has a filter comprising a porous ceramic body, such as a body having pores extending from one face to another face or a foam structure, incorporated therein.
Type:
Grant
Filed:
May 16, 1988
Date of Patent:
June 27, 1989
Assignee:
Foseco International Limited
Inventors:
John R. Brown, Nigel K. Graham, Russell A. King
Abstract: A furnace of kiln for use in the heat treatment of materials or articles has an inner lining comprising boards of refractory, heat-insulating material restrained from inward movement by rails of refractory, heat-insulating material having shoulders at their inward side against the back of which shoulders edge portions of the boards rest.