US3660135A - Linings for ingot molds and foundry molds - Google Patents

Linings for ingot molds and foundry molds Download PDF

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Publication number
US3660135A
US3660135A US840480A US3660135DA US3660135A US 3660135 A US3660135 A US 3660135A US 840480 A US840480 A US 840480A US 3660135D A US3660135D A US 3660135DA US 3660135 A US3660135 A US 3660135A
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United States
Prior art keywords
percent
molds
aluminum
screen
lining
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US840480A
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English (en)
Inventor
Henry Nouveau
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
DOITTAU PRODUITS METALLURG SOC
DOITTAU PRODUITS METALLURGIE SOC A RESPONSABILITE Ltee
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DOITTAU PRODUITS METALLURG SOC
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Filing date
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Application filed by DOITTAU PRODUITS METALLURG SOC filed Critical DOITTAU PRODUITS METALLURG SOC
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Publication of US3660135A publication Critical patent/US3660135A/en
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Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D7/00—Casting ingots, e.g. from ferrous metals
    • B22D7/06—Ingot moulds or their manufacture
    • B22D7/10—Hot tops therefor
    • B22D7/104—Hot tops therefor from exothermic material only
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/26—Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
    • Y10T428/268—Monolayer with structurally defined element
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
    • Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]

Definitions

  • ABSTRACT An exothermic ingot mold lining is water insoluble and can be formed by filtration, but at the same time has high reactivity, and comprises by weight refractory material 35 to 60 percent, asbestos 3 to 7 percent, wood flour 4 to 10 percent, manganese dioxide 11 to 21 percent, cryolite 0.5 to 7 percent, fluorspar 0.5 to 6 percent, binder 4 to 7-percent, and powdered aluminum 10 to 32 percent, the aluminum substantially all passing a No. 45 screen and including 10 to 70 percent that passes a No. 250 screen. The aluminum is thus a mixture of fine and coarse. powder.
  • the present invention relates to exothermic composition for the fabrication of mold elements used as linings for molds during the casting of metals and particularly for the lining of the upper portions of the molds. These linings serve to insulate the liquid metal or a portion of the liquid metal from the mold or the hot top of the mold so as to retard solidification of the metal, particularly adjacent the top of the casting.
  • the invention is more particularly concerned with exothermic mold linings for small castings in which the heat transfer is especially rapid and in which the temperature variations must be more closely regulated according to a predetermined and fairly precise pattern, than in the case of larger castings.
  • exothermic compositions are already known that are suitable for ingot and foundry mold linings.
  • these are mixtures of powdered aluminum of the like, as the oxidizable element, and an oxidizer such as iron oxide, manganese dioxide or sodium or potassium nitrate.
  • an insoluble oxidant such as iron oxide or manganese dioxide
  • the present invention remedies these shortcomings by providing an exothermic composition which has no soluble components and which is accordingly suitable for formation of a mold lining by filtration of a suspension, but which at the same time is of enhanced reactivity.
  • the present invention is characterized by regulation of the grain size of aluminum powder, so as to obtain a staged or phased reaction with the first stage of exothermic reaction utilizing the air occluded in the molded material and a second stage of exothermic reaction utilizing insoluble oxidants for oxidation of the aluminum powder.
  • composition of the present invention is characterized in that it comprises, in addition to the insoluble oxidants such as iron oxide or manganese dioxide, which oxidants are in finely divided form preferably having an AFS index higher than 90, and in addition to fillers and insoluble components such as fluxes of refractory material, and a binder, powdered aluminum of which the grain size is graduated over a range of fineness such that substantially all of the aluminum powder passes a screen having openings of 0.40 mm., more than 95 percent by weight passes a screen having openings of 0.25 mm., more than 50 percent by weight passes a screen having openings of 0.16 mm., and to 70 percent by weight passes a screen having openings of 0.063 mm.
  • insoluble oxidants such as iron oxide or manganese dioxide
  • fillers and insoluble components such as fluxes of refractory material
  • a binder powdered aluminum of which the grain size is graduated over a range of fineness such that substantially all of the aluminum powder passes a screen having opening
  • this mixture it is the finest portion that has the greatest reactivity; and it is the portion of largest grain size whose oxidation is retarded until the temperature of the mold lining, under the combined heating action of the cast metal and the exothermic reaction of the finer particles, reaches the decomposition temperature of the insoluble oxidants.
  • the proportion of the fine and coarse particles can accordingly be adjusted so as to regulate the reaction rate and hence the temperature of the lining at any moment.
  • this granulometric curve is regulated by varying the proportion to each other of two powders of difierent particle sizes, one of the two powders having an average particle size less than 0.063 mm.
  • the insoluble fluxes of the mixture may be for example cryolite and fluorspar.
  • the fillers and the refractory materials are those ordinarily used.
  • the fillers may be organic or inorganic and simply control in the known manner the density and porosity of the molded lining and its strength and other properties such as adhesion to the casting. These fillers can also have a physical action, especially when they are in the form of mineral fibers or organic fibers, to ensure the dispersion of the heavier materials in the suspension and to improve the mechanical resistance of the lining.
  • Refractory materials may for example be silica sand, fire clay, magnesia, etc., their density and grain size being chosen according to the desired porosity to be achieved.
  • the binders may be chosen as desired but phenolic resins and ureaformaldehyde' resins are preferred, as well as organic binders such as starch or potato starch, etc.
  • phenolic resins and ureaformaldehyde' resins are preferred, as well as organic binders such as starch or potato starch, etc.
  • exothermic linings of the present invention can have the following weight per cent composition:
  • Refractory material silicon sand, fire clay or magnesia
  • a granulometric a concentration of 150 to 400 grams of solids per liter.
  • the suspension is introduced into a mold having perforated moldwalls and the water is forced through the perforations by pressure, leaving moist solids in the desired shape of the lining.
  • the moist solid pieces are then oven dried to total dryness.
  • the powders had the following granulometry:
  • the mixture was suspended in water at a concentration of 300 g. of solids per liter and was formed by filtration as described above into the lining for the top of a steelingot mold for casting a chromium steel ingot weighing 90 kgs.
  • the lining was in the form ofa sleeve 18 mm. thick'bordering about the upper 8.5 percent of the volume of the interior of the mold.
  • the resultant cast chrome steel ingot had pipe and inclusions only at the top and amounting to only 4 percent by weight of the casting.
  • a mold element for the exothermic lining of an ingot mold consisting essentially of 10 to 32 percent by weight of powdered aluminum substantially all of which passes a screen having openings of 0.40 mm. and 10 to percent by weight of which passes a screen having openings of 0.063 mm., 35 to 60 percent by weight of a refractory material having a granulometric index from to AFS, 3 to 7 percent by weight of asbestos, 4 to 10 percent by weight of wood flour, l l to 21 percent by weight of an oxidant selected from the group consisting of iron oxide and manganese dioxide, 1 to 13 percent of a water insoluble flux and 4 to 7 percent by weight of an organic binder.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Mold Materials And Core Materials (AREA)
US840480A 1968-08-01 1969-07-09 Linings for ingot molds and foundry molds Expired - Lifetime US3660135A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR161564 1968-08-01

Publications (1)

Publication Number Publication Date
US3660135A true US3660135A (en) 1972-05-02

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US840480A Expired - Lifetime US3660135A (en) 1968-08-01 1969-07-09 Linings for ingot molds and foundry molds

Country Status (3)

Country Link
US (1) US3660135A (enrdf_load_stackoverflow)
FR (1) FR1587079A (enrdf_load_stackoverflow)
GB (1) GB1274454A (enrdf_load_stackoverflow)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4031046A (en) * 1974-04-02 1977-06-21 Firma Tido Chemisch-Technische Produkte Gmbh Exothermic lining for metallurgical purposes and method of making the same

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1027585A (en) * 1911-11-11 1912-05-28 William W Lyons Steel-mold.
US2518738A (en) * 1945-12-05 1950-08-15 Armco Steel Corp Casting of ingots
CA527186A (en) * 1956-07-03 J. Sopcak Edward Mold coating process
US3025153A (en) * 1959-01-21 1962-03-13 Foundry Services Int Ltd Heat-producing mixtures
GB921333A (en) * 1958-07-14 1963-03-20 Revere Camera Co An automatic photographic exposure control
US3144690A (en) * 1961-07-17 1964-08-18 Foseco Int Exothermically reacting shaped products for use in foundry practice
FR1388898A (fr) * 1963-12-31 1965-02-12 Doittau Produits Metallurg Nouvelle composition exothermique pour le garnissage des lingotières d'aciéries oumoules de fonderie
US3172795A (en) * 1961-01-27 1965-03-09 Exothermic refractory materials con- taining oxidizing agents and process
US3183562A (en) * 1961-07-05 1965-05-18 Foseco Int Production of ingots and castings
FR1422499A (fr) * 1964-01-15 1965-12-24 Thomson Houston Comp Francaise Perfectionnements aux condensateurs électrolytiques et aux procédés de fabrication de leurs électrodes
US3231368A (en) * 1962-05-29 1966-01-25 Foseco Int Treatment of molten iron
US3344838A (en) * 1963-12-31 1967-10-03 Sarl Doittau Produits Metallur Method for producing an exothermic lining for ingot and foundry molds and hot tops
US3373047A (en) * 1964-10-06 1968-03-12 Oglebay Norton Co Material for hot top
US3421570A (en) * 1967-02-20 1969-01-14 Elektro Thermit Gmbh Aluminothermic welding process
US3439734A (en) * 1965-12-06 1969-04-22 Foseco Trading Ag Apparatus for forming hot top liners
US3450189A (en) * 1966-08-22 1969-06-17 Int Nickel Co Process of coating metal castings

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA527186A (en) * 1956-07-03 J. Sopcak Edward Mold coating process
US1027585A (en) * 1911-11-11 1912-05-28 William W Lyons Steel-mold.
US2518738A (en) * 1945-12-05 1950-08-15 Armco Steel Corp Casting of ingots
GB921333A (en) * 1958-07-14 1963-03-20 Revere Camera Co An automatic photographic exposure control
US3025153A (en) * 1959-01-21 1962-03-13 Foundry Services Int Ltd Heat-producing mixtures
US3172795A (en) * 1961-01-27 1965-03-09 Exothermic refractory materials con- taining oxidizing agents and process
US3183562A (en) * 1961-07-05 1965-05-18 Foseco Int Production of ingots and castings
US3144690A (en) * 1961-07-17 1964-08-18 Foseco Int Exothermically reacting shaped products for use in foundry practice
US3231368A (en) * 1962-05-29 1966-01-25 Foseco Int Treatment of molten iron
FR1388898A (fr) * 1963-12-31 1965-02-12 Doittau Produits Metallurg Nouvelle composition exothermique pour le garnissage des lingotières d'aciéries oumoules de fonderie
US3344838A (en) * 1963-12-31 1967-10-03 Sarl Doittau Produits Metallur Method for producing an exothermic lining for ingot and foundry molds and hot tops
FR1422499A (fr) * 1964-01-15 1965-12-24 Thomson Houston Comp Francaise Perfectionnements aux condensateurs électrolytiques et aux procédés de fabrication de leurs électrodes
US3373047A (en) * 1964-10-06 1968-03-12 Oglebay Norton Co Material for hot top
US3439734A (en) * 1965-12-06 1969-04-22 Foseco Trading Ag Apparatus for forming hot top liners
US3450189A (en) * 1966-08-22 1969-06-17 Int Nickel Co Process of coating metal castings
US3421570A (en) * 1967-02-20 1969-01-14 Elektro Thermit Gmbh Aluminothermic welding process

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4031046A (en) * 1974-04-02 1977-06-21 Firma Tido Chemisch-Technische Produkte Gmbh Exothermic lining for metallurgical purposes and method of making the same

Also Published As

Publication number Publication date
FR1587079A (enrdf_load_stackoverflow) 1970-03-13
GB1274454A (en) 1972-05-17

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