US3682435A - Bottom brick for ingot molds - Google Patents

Bottom brick for ingot molds Download PDF

Info

Publication number
US3682435A
US3682435A US91562A US3682435DA US3682435A US 3682435 A US3682435 A US 3682435A US 91562 A US91562 A US 91562A US 3682435D A US3682435D A US 3682435DA US 3682435 A US3682435 A US 3682435A
Authority
US
United States
Prior art keywords
plug
percent
composition
refractory material
sand
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
Application number
US91562A
Other languages
English (en)
Inventor
Jan Anders Stensson Lofberg
Per Davidson
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.)
SANDIVKENS JERNVEKS AB
Original Assignee
SANDIVKENS JERNVEKS AB
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by SANDIVKENS JERNVEKS AB filed Critical SANDIVKENS JERNVEKS AB
Application granted granted Critical
Publication of US3682435A publication Critical patent/US3682435A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • 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
    • B22D7/062—Stools for ingot moulds

Definitions

  • the invention pertains to improvements in bottom bricks or bottom plugs for ingot molds.
  • a hole in the bottom to facilitate stripping of the ingot from the mold. This hole is closed during the casting by a brick forming a bottom plug.
  • the invention is also useful in bricks for making a supply channel for pouring the metal into the mold.
  • Previous bottom plugs have been made from chamotte which has certain disadvantages in that the plugs have to be burned during manufacture which causes changes in size and shape and furthermore they are liable to be eroded by the stream of metal poured into the mold so that particles of the plug mix with the cast metal.
  • the chamotte plug also tends to adhere to the ingot after freezing of the metal.
  • the present invention provides a bottom plug which eliminates the disadvantages of previous plugs and which is cheap to manufacture.
  • the plugs according to the invention are made of refractory fine grained material mixed with a binder and are formed without burning or sintering. Thus a plug is obtained which does not change its shape or size after forming and which is resistant to erosion from the metal stream. It further does not easily adhere to the ingot. It has a high mechanical strength and is tight and provides a smooth surface facing the ingot.
  • the bottom bricks or plugs according to the invention are characterized in that at least on the side which faces the ingot they consist essentially of a composition of fine grained refractory material and a binder, preferably an organic binder such as a resin glue.
  • the material can be acid, neutral or basic and can consist of natural sand, quartz, dolomite, olivine or similar material.
  • the refractory material should usually have a grain size such that 80 100 percent passes a screen of 18 mesh US standard (opening 1.0 mm).
  • the particle size distribution of the material below this size can vary. It is possible to use materials a substantial part of which pass a screen of 200 mesh (0.075 mm) but in practice materials are often used 50 percent or more and often 75 percent or more of which remains on a screen of 200 mesh. Satisfactory results have been obtained with sands 50 percent or more of which lie between the limits 200 30 mesh (0.075 0.6 mm).
  • the composition can contain a fibrous refractory material such as asbestos, rock wool or the like in a minor quantity, for instance up to 5 percent.
  • quantity of the binder is 0.5 8 percent by weight of the composition, the bricks having a tight structure and a smooth surface facing the cast metal.
  • FIG. 1 is a vertical section of an ingot mold with a partial section of a bottom plug according tothe invention.
  • FIGS. 2 4 are alternative embodiments on a larger scale than in FIG. 1 of bottom plugs according to the invention.
  • the ingot mold 10 in FIG. 1 has a bottom hole 11 with a frusto conical, downwardly tapering side wall.
  • the purpose of this hole in the ingot mold is to facilitate the stripping of the ingot from the mold after casting.
  • the hole is closed by a matching plug 12.
  • This plug is, as stated above, made of a composition consisting of fine grained refractory material and a binder.
  • the plug 12 illustrated in FIG. 1 is homogeneous while the plug 15 in FIG. 2 is composed of two layers both of which contain fine grained refractory material, the material in the top layer being more heat resistant that the material in the bottom layer.
  • the refractory material preferably should have an average grain size of 0.01
  • the binder can in certain cases be inorganic and consist of, for instance, water glass but the preferred binders are organic, usually a resin glue, often synthetic. Furan resin glue with a hardener such as phosphoric acid has been found especially suitable because this kind of glue is self-hardening at room temperature which makes heating of the fonned plug superfluous and makes it possible to obtain a high accuracy in the size and shape of the plug.
  • the quantity of binder should be 0.5 8 percent by weight. The most suitable range is 0.5 4.5 percent, preferably 1 3 percent of the weight of the refractory-binder composition.
  • a brick according to the invention thus contains in the main the following weight ratio of ingredients:
  • Binder Refractory material Of the refractory material a small quantity, for instance up to 5 percent by weight of the composition, can be a fibrous refractory material as mentioned above.
  • a minor quantity of the refractory material for instance up-to 2 or 3 percent of the composition, can be substituted by e. g. organic material as paper pulp or the like.
  • the brick can be rendered more compact by vibration, ramming and/or pressing, for instance in a. hydraulic pressing machine. In certain cases a slight heating is useful in order to cause the glue to harden but this is not necessary if the binder is self-hardening at room temperature as is the furan resin glue.
  • FIG. 1 An example of a bottom plug or other bottom brick of the homogeneous type shown in FIG. 1 can be mentioned a brick containing 2 percent by weight of furan resin glue, the remainder being lake sand.
  • the sand contains about 90% SiO and has an average grain size of about 0.27 mm.
  • a refractory material with relatively high heat resistance is required, for instance sand with a high content of silica, suitably above percent, or olivine sand.
  • the heat resistance of a quartzite sand increases with the SiO content.
  • the plug 15 in FIG. 2 consists of two layers, the top layer 13 providing contact with the molten metal and the bottom layer 14 providing the necessary mechanical strength.
  • the top or contact layer can suitably consist of a refractory material with very high heat re sistance and also having other desirable properties. It should be resistant to the stream of molten cast metal and it should preferably not be wetted by the cast metal in order to avoid adhesion of the plug to the ingot. Such adhesion can be caused by sintering of the material to the ingot.
  • the average grain size and the binder content can suitably. be the same as for the plug 12 described above.
  • top layer 13 is comparatively thin in comparison with the bottom layer 14 it is economically possible to form it of refractory materials of higher quality and at the same time more expensive than the materials which are suitable for the plug 12.
  • Layer 13 can for instance be formed of zirconium sand or oxides of the metals zirconium, aluminum, magnesium and chromium or other materials having the said desired properties. Sometimes burned or unburned dolomite or limestone can be used.
  • the material in this top layer 13 should have a higher heat resistance than common quartz sand and a sintering temperature above the temperature of the cast metal which usually is steel, suitably above 1,5 C.
  • Zirconium sand has a sintering temperature of about 1,800 C, while quartz sand has a sintering temperature of about l,400 C.
  • the bottom or supporting layer 14 can be made of a cheaper refractory material with a lower heat resistance as for instance quartzite or olivine sand. Also dressed ore, carbon black, graphite, silicon carbide, crushed light concrete and sands containing comparatively little silica such as foundry sand, lake sand or other similar sand can be used. Because of the lower heat resistance some sintering may occur in this layer but this can be permitted.
  • the grain sizes and binder content should also for this layer suitably be approximately the same as earlier defined for the plug 12. The binder content can be somewhat higher, up to 6 percent.
  • the top layer 13 should be as thin as possible without risking the desired function. A thickness of l 20 mm, often 3 mm, has been found suitable.
  • the ingredients for the two layers are mixed and deposited separately, after which the plug is molded and can be compressed by vibrating, ramming and/or pressing, as above mentioned.
  • a plug consisting of two layers may have the following distribution of material in percent by weight:
  • the binder content can be equal in both layers or somewhat higher in the bottom layer.
  • the layers 13 and 14 need not be sharply distinguished from each other but can merge gradually. Likewise there can be more than two layers, the plug consisting of a number of successive layers with gradually changing properties. In the plug in FIG. 2 it is, for instance, possible to mold the plug with two layers, the top layer being more heat resistant, and then to provide an additional thin layer on top of the plug by flame spraying as below described.
  • the plug according to the invention is advantageous in this regard because the cheaper sand qualities employed in the bottom layer 14 generally have a better heat conduction than the more expensive materials in the top layer 13.
  • the plug can be provided with recesses or inserted bodies or layers with good heat conduction (not shown).
  • the plug according to the invention is manufactured without burning or sintering which is a substantial advantage in comparison with earlier known plugs of burnt brick material because the manufacturing tolerances can be held within narrow limits. With some binders a slight heating may be necessary, which, however, does not substantially affect the shape of the plug. If a binder is employed which is self-hardening at room temperature, such as furan resin glue, no heating at all is necessary.
  • the top surface of the plug can be covered by a thin layer of some heat resistant oxide which can be applied, for instance by flame spraying.
  • This thin layer can consist of oxide of zirconium or oxide of chromium or some other similar refractory oxide or other substance having a high heat resistance. In this way a higher resistance against erosion by the metal stream and a diminishing of the tendency of the brick to adhere to the cast metal can be obtained.
  • FIG. 3 Another way of improving the erosion resistance of the plug is illustrated in FIG. 3.
  • the upper surface of the plug 20 is covered by a metal sheet 21 which can be anchored to the plug as by means of nails 22.
  • a steel sheet of for instance 0.5 mm thickness can be used.
  • the sheet provides a temporary protection during the beginning of the casting after which it melts and mixes with the ingot.
  • This embodiment can be used for the homogeneous plug in FIG. 1 as well as for the two layer plug in FIG. 2.
  • the metal sheet may be extended upwardly by a flange 23 in order to prevent splashing and wave formation in the molten metal during the beginning of the casting or this flange may be omitted.
  • FIG. 3 is shown also an upward depression 24 in the bottom of the plug in order to save material. The mechanical strength of the plug with this depression is sufficient because of the arch effect against the inclined edge. Such depressions can be used also in the other embodiments or omitted.
  • FIG. 4 is shown a plug 30 which has a depression 31 in its top surface in order to eliminate splashing and wave formation in the metal thereby diminishing the erosion of the mold by the violent sideward flow which occurs when the stream of metal reaches the bottom of the mold.
  • the surface of the ingot is also improved if the waves and splashing of the metal is reduced as much as possible.
  • the plug in FIG. 4 can be made either of a homogeneous material as in FIG. 1 or in layers as in FIG. 2, and it can be covered by a protective metal sheet as shown in FIG. 3 or coated with a thin top layer as described above but not illustrated.
  • the invention has been described for a bottom plug of an ingot mold and has its main use for such plugs.
  • the invention can, however, be used also for bricks which are used for supply channels to ingot molds which are cast from the bottom, the internal surfaces of such bricks being exposed to the molten metal under conditions which in, essential respects are similar to the conditions of the above described bottom plugs used in ingot molds.
  • Bottom plug for an ingot mold for casting metals said plug having a high resistance to erosion and a low tendency to adhere to such cast metal
  • said plug consisting of an unburned compact having a composition consisting of (a) fine grained inorganic refractory material of the group consisting of sand of dolomite, olivine, zirconium, alumina, chromium oxide, and sand having a silica content in excess of percent as quartz sand, said refractory material having an average grain size of from 0.0l-l.0 mm, bonded together into a unitary body by means of (b) an organic binder in the amount of from 0.5-8.0 percent by weight based on the weight of the composition, said organic binder being the only organic constituent of said composition, the plug having a compact and impervious structure and a smooth surface facing the cast metal.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Compositions Of Oxide Ceramics (AREA)
  • Mold Materials And Core Materials (AREA)
  • Ceramic Products (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)
US91562A 1964-06-22 1970-11-20 Bottom brick for ingot molds Expired - Lifetime US3682435A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE757964 1964-06-22
SE1120564 1964-09-18

Publications (1)

Publication Number Publication Date
US3682435A true US3682435A (en) 1972-08-08

Family

ID=26654786

Family Applications (1)

Application Number Title Priority Date Filing Date
US91562A Expired - Lifetime US3682435A (en) 1964-06-22 1970-11-20 Bottom brick for ingot molds

Country Status (7)

Country Link
US (1) US3682435A (ja)
AT (1) AT265544B (ja)
BE (1) BE665684A (ja)
DE (1) DE1483628A1 (ja)
FI (1) FI46464C (ja)
GB (1) GB1107454A (ja)
NO (1) NO115813B (ja)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3807684A (en) * 1972-12-14 1974-04-30 Nippon Crucible Co Mold stool
US3874628A (en) * 1973-05-18 1975-04-01 Robert C Jarron Repaired base plate for ingot mold
US3971117A (en) * 1975-07-23 1976-07-27 Hilti Aktiengesellschaft Method of repairing ingot mold bottoms
US4005846A (en) * 1975-11-19 1977-02-01 Nalco Chemical Company Ingot mold base member
US4090551A (en) * 1976-03-15 1978-05-23 Allegheny Ludlum Industries, Inc. Mold protection device for the bottom of ingot molds
US4154289A (en) * 1976-04-06 1979-05-15 Marie-Therese Simian Gating system
US4749022A (en) * 1986-11-28 1988-06-07 Marie-Therese Simian Foundry gating system
US4907640A (en) * 1986-11-28 1990-03-13 Marie-Therese Simian Foundry gating system
US6179042B1 (en) 1999-05-21 2001-01-30 Alcoa Inc. Non-hot crack bottom block for casting aluminum ingot
US6334603B1 (en) * 1998-02-26 2002-01-01 Mitsubishi Materials Corporation Mold for producing silicon ingot and method for fabricating the same
US20080128271A1 (en) * 2005-01-28 2008-06-05 Geosafe Corporation Apparatus for Rapid Startup During In-Container Vitrification

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0628947B2 (ja) * 1987-03-16 1994-04-20 品川白煉瓦株式会社 道具れんが用二層構造耐熱板

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3123878A (en) * 1964-03-10 Method of making hot tops for ingot molds
US3146504A (en) * 1962-02-12 1964-09-01 Eureka Fire Brick Works Mold plug

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3123878A (en) * 1964-03-10 Method of making hot tops for ingot molds
US3146504A (en) * 1962-02-12 1964-09-01 Eureka Fire Brick Works Mold plug

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3807684A (en) * 1972-12-14 1974-04-30 Nippon Crucible Co Mold stool
US3874628A (en) * 1973-05-18 1975-04-01 Robert C Jarron Repaired base plate for ingot mold
US3971117A (en) * 1975-07-23 1976-07-27 Hilti Aktiengesellschaft Method of repairing ingot mold bottoms
US4005846A (en) * 1975-11-19 1977-02-01 Nalco Chemical Company Ingot mold base member
US4090551A (en) * 1976-03-15 1978-05-23 Allegheny Ludlum Industries, Inc. Mold protection device for the bottom of ingot molds
US4154289A (en) * 1976-04-06 1979-05-15 Marie-Therese Simian Gating system
US4749022A (en) * 1986-11-28 1988-06-07 Marie-Therese Simian Foundry gating system
US4907640A (en) * 1986-11-28 1990-03-13 Marie-Therese Simian Foundry gating system
US6334603B1 (en) * 1998-02-26 2002-01-01 Mitsubishi Materials Corporation Mold for producing silicon ingot and method for fabricating the same
US6179042B1 (en) 1999-05-21 2001-01-30 Alcoa Inc. Non-hot crack bottom block for casting aluminum ingot
US20080128271A1 (en) * 2005-01-28 2008-06-05 Geosafe Corporation Apparatus for Rapid Startup During In-Container Vitrification
US20080167175A1 (en) * 2005-01-28 2008-07-10 Lowery Patrick S Refractory Melt Barrier For In-Container Vitrification

Also Published As

Publication number Publication date
BE665684A (ja) 1965-10-18
FI46464C (fi) 1973-04-10
DE1483628A1 (de) 1969-03-13
NO115813B (ja) 1968-12-09
AT265544B (de) 1968-10-10
GB1107454A (en) 1968-03-27
FI46464B (fi) 1973-01-02

Similar Documents

Publication Publication Date Title
US3682435A (en) Bottom brick for ingot molds
US3917110A (en) Stopper rod having fibrous protective sleeve
KR940002021B1 (ko) 연속주조용 노즐 및 그 제조방법
GB1469513A (en) Tundishes
GB1593371A (en) Refractory structures
CA1075724A (en) Casting of metals
CA1119622A (en) Refractory lining for a tundish
US3297296A (en) Hot top composition for casting molds
US3810506A (en) Molding for use in steel ingot making by bottom pouring and method of making steel ingot
US3848655A (en) Method of making a steel ingot
US3876420A (en) Thermal insulation molten metal
US2558402A (en) Mold composition
US4036282A (en) Process of ingot casting
US3196504A (en) Cast nozzle inserts
US2169385A (en) Manufacture of foundry molds
USRE31589E (en) Thermal insulation molten metal
CA1066479A (en) Casting of molten metals
US3391726A (en) Hot top lining
US4667858A (en) Filler material for filling an outlet aperture of a casting ladle or similar container and a process for producing the filler material
US2169384A (en) Manufacture of foundry molds
US4900603A (en) Refractory, heat insulating articles
US3672918A (en) Hot tops
JPS6047223B2 (ja) 連続鋳造用浸漬ノズルの製造方法
US3706682A (en) Hot tops and mixture of materials therefor
US2169386A (en) Manufacture of foundry molds