US1409040A - Making ingots - Google Patents

Making ingots Download PDF

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US1409040A
US1409040A US460673A US46067321A US1409040A US 1409040 A US1409040 A US 1409040A US 460673 A US460673 A US 460673A US 46067321 A US46067321 A US 46067321A US 1409040 A US1409040 A US 1409040A
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mold
ingot
gasket
stool
pad
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US460673A
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George E Thackray
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D7/00Casting ingots, e.g. from ferrous metals
    • B22D7/06Ingot moulds or their manufacture
    • B22D7/062Stools for ingot moulds

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  • My invention relates to improvements in making ingots with special reference to producing an ingot free from fins or projections on its lower portion'in order to prevent shrinkage strains and cracks while cooling, and While this is adapted to various forms of ingots, it is especially useful with ingots of the type having their larger ends upward, which are thus made in order to concentrate the piping or shrinkage cavities in the upper portion within the refractory material or lining of the sink-head top which may be used in this connection.
  • Ingots and particularly those of the big-end-up type, should not have fins projecting from their lower end between the stool and the ingot mold, caused by molten ingot metal penetrating the joint or crack at this location, for the reason that on account of the taper of the mold the ingot would be held somewhat thereby, and as it cools the fins would hold it and in a measure prevent its contraction when cooling, thus producing shrinkage cracks in and extending inwardly from the surface, which makes defects in the ro'duct. If fins are thus formed it makes it difiicult o remove the .ingot from the mold, as it has to bewithdrawn from the larger end, and the fin on the smaller end would prevent this.
  • my improved manner of preparing ingot molds and casting ingots therein I obviate these difficulties.
  • a metal stool having a pad projecting upwardly from the upper surface thereof, which pad is a little smaller than the inside of the bottom of the ingot mold and conforms to the general shape thereof, leaving a groove or space between said pad and the bottom of the inside of the ingot mold. parallel or of any other form desired.
  • a gasket which may be made of one continuous form or ring and of a shape and size to fit into the groove aforesaid. After the mold is placed in position on the stool, the gasket is dropped therein between the mold and the pad and will fall in or adj acent to the open side of the groove. After this is done the gasket may be tamped into the groove by a tamping tool and the bottom of the mold is thus effectively sealed.
  • This gasket may be of asbestos or other similar refractory and preferably flexible or compressible material, and in order to maintain its shape it may be provided with a wire core on which asbestos rope or other similar refractory material may be wound, woven, or otherwise secured. If the material of the gasket is sufliciently stiff and has enough strength the gasket may be used wlthout the wire core.
  • the refractory material which I prefer to use is. asbestos rope or other fibrous, pliant or flexible material, which is at the same time somewhat porous and contains air cavities so that. it is easily compressible.
  • compressible means material or materials which are capable of being compressed together or into a smaller space or volume, and this is true of my gasket by reason of the character of the materials used and the voids therein.
  • Mud or slurry previously used is therefore not-compressible in the sense of my invention, as my gasket is compressible by reduction of its volume when-placed or after it is in the groove, as herein described.
  • This gasket may be coated with graphite, talc, or other refractory and non-adherent material, either previously mixed with water or other liquid to a creamy consistency or otherwise applied to the gasket in order to insure that it will strip from the ingot so that it may be used again.
  • the mold can be cleaned out by the use of an air suction pipe which is introduced therein, which withdraws any particles of sand, dust, dried mud, fragments of the sink head top lining or other loose material which may have been deposited therein in any manner, so that the interior of my mold is absolutely clean and free from any foreign matter. that would cause inclusions or defects in the ingot metal.
  • gasket made of a one piece ring, or square with rounded corners
  • it may be composed of one or more pieces of asbestos rope or similar refractory, flexible and compressible material, overlapping or arranged in such a way as to fill the, groove, but this is not. as convenient as the continuous shaped gasket.
  • Figure 1 is a transverse sectional elevation through the intermediate portion of an ingot mold, the sink head top and stool on which it rests, showing one form of apparatus used in connection with my invention.
  • Figure 2 is a side view of one form of tamp ing bar which I may use to force the gasket in place within the groove.
  • Figure 3 is a cross section of the gaskets which are formed of asbestos or other material as previously described, wound, woven, or otherwise secured upon a core, which may be composed of one or more wires as illustrated, but as above stated, I may not use wire cores if the gasket material is stiff and coherent enough and holds together sufficiently for placing in position.
  • Figure 4 is a vertical sectional elevation through the bottom of another slightly modified form of ingot mold and the stool upon which it rests.
  • Figure 5 is a plan view of the gasket used to seal the groove in the bottom of the ingot mold illustrated in Figure 1.
  • Figure 6 is to top plan View of one form of stool which may be used with the ingot mold illustrated in F igure 1.
  • Figure 7 is a plan View of another form of. stool used with the ingot mold of Figure 4.
  • Figure 8 is a plan of the gasket used with the ingot mold and stool illustrated in Figure 4:.
  • Figure 9 is another form of tamping tool which may be used for tamping the gasket into position at the base of the ingot mold of Figure 1.
  • the casin for the sink head top is 12, the base flan t ereof is 13, which may be provided wii downwardly projecting lugs 14 in order to position and center it-on the top of the mold and this calsing is provided with lifting lugs 15 preferably made integral therewith for the purpose of handling with a crane chain or-otherwise, while 16'is the upper flange of the sink head top casing, and the refractory lining of the sink head casing is 17
  • a metal suction pipe 18 is provided for the purpose of extracting or withdrawing from the mold cavity any foreign material as heretofore mentioned, and this pipe is provided with a regulating valve 19 and the flexible suction hose 20,which is connected to any suitable source of vacuum or partial vacuum provided withfan, syphon or other suction apparatus, not shown.
  • 21 is a tamping bar which may be used for tamping the gaskets 11 and 28 in place after they have'been dropped into or placedgadjacent to the groove between the bottom of the ingot mold and the edges of the stool pad, one end of the tamping bar 22 being curved as illustrated to correspond to the round corners of the groove between the pad 9 and the ingot mold 1 or the curved groove of the mold 24, while the other end 23 is flat and narrow for use in the straight portions of the groove. As illustrated in Figure 4 this tamping bar is shown in dotted lines in position for tamping the gasket 28 in the groove adjacent to the bottom of the ingot mold 24.
  • the mold of Figure 4 is 24, and this is provided with an inwardly tapering lower end of concave and convex form, the concave portion being 25 and the convex portion 26, the idea of this construction being to provide an ingot with a smaller end, which assists in preventing fins by reason of the quick chillingof the lower portion of the ingot end due to its small mass as compared with that of the adjacent mold and stool.
  • 27 is the pad on the stool 7, which is of circular form adapted to receive the gasket 28 between the edges of said pad and the lower inner portion 26 of the ingot mold 24.
  • the gasket 11 is provided with a single wire core 29, or it may be provided with a plurality of wires such as 30 twisted together in the form of a cable. As previously stated these gaskets may, however, be made without a center or core.
  • 31 is a tamping bar formed with a rectangular portion 32 with rounded corners adapted to fit within the groove in the base of the ingot mold, so that the gasket 11 may be tamped therein by a. few movements of the tamping bar instead of working more in detail as with the tamping bar 21.
  • Apparatus for casting ingots comprising an ingot mold, a stool on which said mold is seated provided with a pad of lesser size than and extending upwardly into the mold bottom and a pliant and compressible gasket forced between the pad and the mold bottom to seal the same.
  • An ingot mold mounted on a stool provided with a pad or projection extending upwardly for a short distance into the lower portion of the ingot mold, said pad being of lesser size than the mold bottom thereby forming a groove between the mold and said pad, a ring or continuous gasket formed of fibrous or compressible refractory material provided with a stiff metallic core whereby it retains its shape, said gasket being forced into said groove to seal the mold bottom.
  • An ingot mold mounted on a stool provided with a pad or projection extending upwardly for a short distance into the lower portion of the ingot mold, said pad being of lesser size than the mold bottom thereby forming a groove between the mold and said pad, a sink head top on the mold, a ring or continuous gasket formed of fibrous or compressible refractory material provided with a stiff metallic core whereby it retains its shape, said gasket being forced into said groove to seal the mold bottom.
  • the method of making ingots consisting of mounting an ingot mold on a stool provided with a pad of size less than that of the interior of the mold bottom and projecting upwardly therein and forcing a gasket between the pad and the mold to seal the mold bottom, and then pouring metal into said mold 7.
  • the method of making ingots which consists in mounting an ingot mold on a stool provided with a pad of a size less than that of the interior of the mold bottom and projecting upwardly therein thereby forming a groove between said pad and mold bot tom, then closing said groove by means of a gasket inserted in said groove to seal the, mold bottom and then pouring metal into said mold.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Moulds, Cores, Or Mandrels (AREA)

Description

G. E. THACKRAY.
MAKING INGOTS.
APPLICATION FILED APR. 12; 1921.
Patented Mar. 7, 1922.
PATENT OFFICE.
GEORGE E. THACKRAY, OF WESTMQ ZT BOROUGH, PENNSYLVANIA.
MAKING INGOTS.
Specification of Letters Patent.
Patented Mar. '7, 1922.
Application filed April 12, 1921. Serial No. 460,673.
' To all whom it may concern;
Be it known that I, GEORGE E. THACKRAY, a citizen of the United States, and a resident of the borough of Westmont, county of Cainbria, and State of Pennsylvania, have invented-certain new and useful Improvements in Making Ingots; and I'do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.
My invention relates to improvements in making ingots with special reference to producing an ingot free from fins or projections on its lower portion'in order to prevent shrinkage strains and cracks while cooling, and While this is adapted to various forms of ingots, it is especially useful with ingots of the type having their larger ends upward, which are thus made in order to concentrate the piping or shrinkage cavities in the upper portion within the refractory material or lining of the sink-head top which may be used in this connection. Ingots, and particularly those of the big-end-up type, should not have fins projecting from their lower end between the stool and the ingot mold, caused by molten ingot metal penetrating the joint or crack at this location, for the reason that on account of the taper of the mold the ingot would be held somewhat thereby, and as it cools the fins would hold it and in a measure prevent its contraction when cooling, thus producing shrinkage cracks in and extending inwardly from the surface, which makes defects in the ro'duct. If fins are thus formed it makes it difiicult o remove the .ingot from the mold, as it has to bewithdrawn from the larger end, and the fin on the smaller end would prevent this. By means of my improved manner of preparing ingot molds and casting ingots therein I obviate these difficulties.
Trouble has always been had due to the joint between the ingot mold and the stool upon which it rests in order to prevent entrance therein of molten steel. It has been which groove may be taper or the ordinary practice to pour slurry or clay wash formed of loam, clay, etc., of a powdered character mixed with water to form a grout of creamy consistency into the ingot niold after it is seated on the stool with the idea of sealing the crack or joint between the lngot mold and the stool, and the water was evaporated therefrom by the heat of the mold and stool due to previous use. This, however, leaves irregular and loose lumps of refractory material in the bottom of the mold, and when steel or other metal is poured therein this refractory material may be floated upwardly to various extents, and if retained in the ingot causes defects due to inclusions thereof.
Although my means of sealing bottoms of ingot molds is particularly applicable and useful in connection with making ingots with large ends upward, it is also applicable to the ordinary types with large ends down, and when used under such conditions will provide an ingot with a more perfect bottom and which will consequently handle better and roll better without forming laps or seams and one that will enter the roll passes more readily than an ingot having a bottom fin.
In order to practice my invention I provide a metal stool having a pad projecting upwardly from the upper surface thereof, which pad is a little smaller than the inside of the bottom of the ingot mold and conforms to the general shape thereof, leaving a groove or space between said pad and the bottom of the inside of the ingot mold. parallel or of any other form desired.
Instead of employing the usual mud or slurry to seal the joint which causes inclusions in the ingot as before stated, I provide a gasket which may be made of one continuous form or ring and of a shape and size to fit into the groove aforesaid. After the mold is placed in position on the stool, the gasket is dropped therein between the mold and the pad and will fall in or adj acent to the open side of the groove. After this is done the gasket may be tamped into the groove by a tamping tool and the bottom of the mold is thus effectively sealed. This gasket may be of asbestos or other similar refractory and preferably flexible or compressible material, and in order to maintain its shape it may be provided with a wire core on which asbestos rope or other similar refractory material may be wound, woven, or otherwise secured. If the material of the gasket is sufliciently stiff and has enough strength the gasket may be used wlthout the wire core.
The refractory material which I prefer to use is. asbestos rope or other fibrous, pliant or flexible material, which is at the same time somewhat porous and contains air cavities so that. it is easily compressible.
By compressible I mean material or materials which are capable of being compressed together or into a smaller space or volume, and this is true of my gasket by reason of the character of the materials used and the voids therein.
This is not true of the mud or slurry previously used, as these materials are not compressible and when put in place without pressure or with only a slight pressure they may change their form or shape by plastic flow, but they are not compressible as above explained, as their volume is not decreased. Mud or slurry previously used is therefore not-compressible in the sense of my invention, as my gasket is compressible by reduction of its volume when-placed or after it is in the groove, as herein described.
This gasket may be coated with graphite, talc, or other refractory and non-adherent material, either previously mixed with water or other liquid to a creamy consistency or otherwise applied to the gasket in order to insure that it will strip from the ingot so that it may be used again.
'My gasket is not friable and will not break into pieces or produce spalls or frag-.
ments as will the dried mud or slurry previously used, but in order to be sure that no other foreign material that might cause defects in the ingot is in the mold, the mold can be cleaned out by the use of an air suction pipe which is introduced therein, which withdraws any particles of sand, dust, dried mud, fragments of the sink head top lining or other loose material which may have been deposited therein in any manner, so that the interior of my mold is absolutely clean and free from any foreign matter. that would cause inclusions or defects in the ingot metal.
Although I have shown a gasket made of a one piece ring, or square with rounded corners, it may be composed of one or more pieces of asbestos rope or similar refractory, flexible and compressible material, overlapping or arranged in such a way as to fill the, groove, but this is not. as convenient as the continuous shaped gasket.
I have described my invention in connection with steel ingots, but it will be readily understood that this is applicable to ingots or other articles made of any metal whatsoeverl Having thus given a general description of my invention, I will now, in order to make the matter more clear, refer to the annexed sheet of drawings, which forms part of this specification, and in which like character refer to like parts:
Figure 1 is a transverse sectional elevation through the intermediate portion of an ingot mold, the sink head top and stool on which it rests, showing one form of apparatus used in connection with my invention. Figure 2 is a side view of one form of tamp ing bar which I may use to force the gasket in place within the groove. Figure 3 is a cross section of the gaskets which are formed of asbestos or other material as previously described, wound, woven, or otherwise secured upon a core, which may be composed of one or more wires as illustrated, but as above stated, I may not use wire cores if the gasket material is stiff and coherent enough and holds together sufficiently for placing in position. Figure 4 is a vertical sectional elevation through the bottom of another slightly modified form of ingot mold and the stool upon which it rests. Figure 5 is a plan view of the gasket used to seal the groove in the bottom of the ingot mold illustrated in Figure 1. Figure 6 is to top plan View of one form of stool which may be used with the ingot mold illustrated in F igure 1. Figure 7 is a plan View of another form of. stool used with the ingot mold of Figure 4. Figure 8 is a plan of the gasket used with the ingot mold and stool illustrated in Figure 4:. Figure 9 is another form of tamping tool which may be used for tamping the gasket into position at the base of the ingot mold of Figure 1.
Referring now to the characters of ref erence on the drawings: 1 is an ingot mold illustrated in Figure 1; 2 are the top lifting lugs thereof, preferably made integral therewith; 3 are the bottom hold down lugs, but if this mold is used inverted they become the lifting lugs thereof; 4 is a staple projecting from the side of the mold for convenience in handling the same; '5 is the'interiormold cavity of the ingot mold 1; 6 is a stool illustrated in Fi ures 1 and6; 7 is a stool illustrated'in Figures 4 and 7; 8 is the lower portion of the ingot mold cavity illustrated in Figure 4; 9 is the pad or projection on the stool 6; 10 are projections on the stool to assist in positioning the molds thereon and to insure that the groove between the ingot mold and the stool is of sufficiently uniform size throughout in order to receive the gaskets 11 and 28, which are illustrated in Figures 1, 3, 4;, 5 and 8. The casin for the sink head top is 12, the base flan t ereof is 13, which may be provided wii downwardly projecting lugs 14 in order to position and center it-on the top of the mold and this calsing is provided with lifting lugs 15 preferably made integral therewith for the purpose of handling with a crane chain or-otherwise, while 16'is the upper flange of the sink head top casing, and the refractory lining of the sink head casing is 17 A metal suction pipe 18 is provided for the purpose of extracting or withdrawing from the mold cavity any foreign material as heretofore mentioned, and this pipe is provided with a regulating valve 19 and the flexible suction hose 20,which is connected to any suitable source of vacuum or partial vacuum provided withfan, syphon or other suction apparatus, not shown. As illustrated in Figures 2 and 4, 21 is a tamping bar which may be used for tamping the gaskets 11 and 28 in place after they have'been dropped into or placedgadjacent to the groove between the bottom of the ingot mold and the edges of the stool pad, one end of the tamping bar 22 being curved as illustrated to correspond to the round corners of the groove between the pad 9 and the ingot mold 1 or the curved groove of the mold 24, while the other end 23 is flat and narrow for use in the straight portions of the groove. As illustrated in Figure 4 this tamping bar is shown in dotted lines in position for tamping the gasket 28 in the groove adjacent to the bottom of the ingot mold 24. The mold of Figure 4 is 24, and this is provided with an inwardly tapering lower end of concave and convex form, the concave portion being 25 and the convex portion 26, the idea of this construction being to provide an ingot with a smaller end, which assists in preventing fins by reason of the quick chillingof the lower portion of the ingot end due to its small mass as compared with that of the adjacent mold and stool. 27 is the pad on the stool 7, which is of circular form adapted to receive the gasket 28 between the edges of said pad and the lower inner portion 26 of the ingot mold 24. As illustrated in Figure 3 the gasket 11 is provided with a single wire core 29, or it may be provided with a plurality of wires such as 30 twisted together in the form of a cable. As previously stated these gaskets may, however, be made without a center or core.
Asillustrated in Figure 9, 31 is a tamping bar formed with a rectangular portion 32 with rounded corners adapted to fit within the groove in the base of the ingot mold, so that the gasket 11 may be tamped therein by a. few movements of the tamping bar instead of working more in detail as with the tamping bar 21.
Having thus described my invention, what I claim and desire to secure by Letters Patent is 1. Apparatus for casting ingots comprising an ingot mold, a stool on which said mold is seated provided with a pad of lesser size than and extending upwardly into the mold bottom and a pliant and compressible gasket forced between the pad and the mold bottom to seal the same.
2. The combination of an ingot mold with a stool on which it is seated provided with a pad of lesser size than the mold bottom and extending upwardly therein, thereby forming a groove between the mold bottom and the edges of said pad and a continuous gasket formed of compressible material inserted in said groove and compressed therein to seal the mold bottom.
3. The combination of an ingot mold with a stool on which it is seated provided with a pad of lesser size than the mold bottom and extending upwardly therein, thereby forming a groove between the mold bottom and the edges of said pad, and a continuous rin gasket rovided with a metal core on whic fibres o asbestos or similar compressible refractory material is mounted.
4. An ingot mold mounted on a stool provided with a pad or projection extending upwardly for a short distance into the lower portion of the ingot mold, said pad being of lesser size than the mold bottom thereby forming a groove between the mold and said pad, a ring or continuous gasket formed of fibrous or compressible refractory material provided with a stiff metallic core whereby it retains its shape, said gasket being forced into said groove to seal the mold bottom.
5. An ingot mold mounted on a stool provided with a pad or projection extending upwardly for a short distance into the lower portion of the ingot mold, said pad being of lesser size than the mold bottom thereby forming a groove between the mold and said pad, a sink head top on the mold, a ring or continuous gasket formed of fibrous or compressible refractory material provided with a stiff metallic core whereby it retains its shape, said gasket being forced into said groove to seal the mold bottom.
'6. The method of making ingots consisting of mounting an ingot mold on a stool provided with a pad of size less than that of the interior of the mold bottom and projecting upwardly therein and forcing a gasket between the pad and the mold to seal the mold bottom, and then pouring metal into said mold 7. The method of making ingots which consists in mounting an ingot mold on a stool provided with a pad of a size less than that of the interior of the mold bottom and projecting upwardly therein thereby forming a groove between said pad and mold bot tom, then closing said groove by means of a gasket inserted in said groove to seal the, mold bottom and then pouring metal into said mold.
8. The method ofmaking ingots consisting of mounting an ingot mold on a stool the mold, then cleaning out the foreign maprovided'pvith a pad of the general shape of terial from the interior of said mold bysuethe interior of the mold bottom but of less tion and then pouring the metal into said 10 size, thereby forming an upwardly opening mold.
5 space between said pad and mold bottom, In wltness whereof I hereunto afiix my then inserting a gasket in said groove to seal signature. the mold bottom, placing a sink-head top on GEORGE E. THACKRAY.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3163898A (en) * 1960-05-06 1965-01-05 Quigley Co Sealing ring and mat for ingot mold
US3206154A (en) * 1962-12-31 1965-09-14 Quigley Co Production of steel ingots

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3163898A (en) * 1960-05-06 1965-01-05 Quigley Co Sealing ring and mat for ingot mold
US3206154A (en) * 1962-12-31 1965-09-14 Quigley Co Production of steel ingots

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