US2612667A

US2612667A - Ingot casting mold

Info

Publication number: US2612667A
Application number: US38470A
Authority: US
Inventors: Gombosh John
Original assignee: Individual
Current assignee: Individual
Priority date: 1948-07-13
Filing date: 1948-07-13
Publication date: 1952-10-07
Anticipated expiration: 1969-10-07

Description

Och 1952 J. GOMBOSH INGOT CASTING MOLD Filed July 1a, 1948 I INVENTOR. JOHN GOMBQSH.

$2,, M, #MM

Patented Oct. 7, 1952 UNIT-1E1); STAT ES PATENT OFFICE :moor CASTING-MOLD John Gombosh, Pittsburgh, Pa. f..Application July 13, 1948,- Serial.No.38,47ll

' 6 Claims. (01. 23- 147) This invention relates to metal founding, and

'moreparticularly, "to the casting of large'metal 'bodiessuch as ingots where piping has heretofore "been a detrimental factor.

This application is a continuation-impart: of an-earlier or parent application, Serial No. 559,- 763,'issued"'February 8, 1949, filed October 21, 1944,

,noWPat-ent No. 2,461,052, for Method 'ofCasting.

The apparatus of this invention has features in common" with the-said earlier-filed application,

is mounted for vertical movement in the mouth ofthe-cavity so that it may move downwardly and compensate'fo shrinkage of themetal in the mold cavity. In anotherembodiment of the invention shown'inthe-saidapplication, both the structure-forming theperipheral trough and the separator -plate-are-mounted for vertical movement with respeetfto the mold body. In both cases, compensation is provided for shrinkage of the nietal-within-the mold cavity and such com pensation is effective to' reduce the detrimental effects dueto' the formation of pipes in the cas ing. r

This invention relates generally to the structure bf' the moldbyr-which compensation is provided f: for s shrinkage within the mold cavity. More-specifically;-this invention is concerned with an arrangementlay-which the structure forming the peripheral trough about the pour opening to thenn'old -cavity=is mounted**for--movement to compensate for shrinkage of the-metalwithin the mold; cavity. "In addition, thisinvention'provides an improved separator plate" structure for positioningover the'pour opening of. the'mold cavity after suchcavity' has" been filled to overflowing. "fThe'inventi'on'may be "more fully understood by"reference"to' the accompanying drawings, in which: U

Figure 1 is a vertical sectionalview of. an ingot mold'having atrough structureirr its upper end;

. I52 7 Figure. 2 is a view'slmilartoFl'igure 1 showin the mold cavityffllled to overflowing-andwith a, separator: plate; positioned over the trough structure;

. Figure 3 is a, partial vertical sectionalfview showingadditional molten material poured over the separator plate;

Figure 4 is an enlarged plan view,'-part the'reof being broken. away, of the separator. plate: and

Figure 5 is a sectional" view taken substantially along the line VV of Figure 4.

In thedrawings, the numeral [designates a conventional ingot mold having a .fru'stro-c'onical shaped trough structure 2 friction-ally engaged with the sides of themcld adjacent the upper. end thereof. .Thetrou'gh structure 2 is positioned atthe upper end of the mold .cavity' 3 and provides a trough 4 into which dross and impurities floating on the molten metal in the cavity t may overflow through an openingo' located centrally of the trough. The trough structure is provided with vertically? depending flanges 6 which are placed in frictional'engagem'ent with the inner surfaces of 'themo'ld l for positioning the structure therein. Side members I extendangularly inwardly from the top edges of the" flanges 6 "and their terminaledgesdefine'gthe pour opening" 5 which is rectangular inpshape. The trough'structure 2 comprises ,a' central bodyIpo-rtion 8 which is preferably formed. of sheet metal and bent to give the structure 2 the desired contour. The sheet metal 8 is provided with a coating 9 of heatresistant refractory material onits inner surface and a similar, coating [0 on its outer surface. The sheet metal 8 imparts strength to thet'rough and the refractory coatings 9. and I0 enable it to withstand the1intenseheat of themolten metal.

When thetrou'gh structure 2 hasbeenppositioned in the mold as shown in Figure'l, the mold is ready'for casting'metal therein. The

molten metal is introduced through the opening 5, or through the bottom if. abottom pourmold is used, and the cavity'tisfllleduritilit flows over .the edges of the opening 5.into'the trough 4. As pointed out above, the overflow carries with it dross and..impurities floating on the. surface of. the molten metal. 'The overflow is continued until the trough is partially filled, it being'preferred toystop'flthe pouringhefore the level of'the liquid in the. trough approaches the edges of the opening 5.

After metalhas overflowed into the troughill, a Separator platev I I is placed in position over'the opening" 5, as shown in Figure; 2. f The plate I l is a cover having aflat ortion I2 and'diverging flanges I3 depending angularly from the edges of the top I2 for supporting engagement with the side members I of the trough structure 2. The separator plate II comprises a central body portion I4 preferably constructed from sheet metal and having an under coating I5 and an upper coating I6 of heat-resistant refractory material as best shown in Figure 4. The trough will have previously been filled with sufiicient material that the lower edges of theflanges I3 will dip into such material. Movement of the lower edges of the flanges I 3 into the molten metal in the trough 4 will chill the metal and a skin of solid metal will be formed between the flanges I3 and side members I which will be effective to hold the separator plate II in position on the trough structure 2.

After plate I I is secure on the trough structure 2, additional molten material is poured into the top of the mold to cover the plate I I as shown in Figure 3. In the preferred practice of the invention, the additional material poured on the top is molten metal and the top I2 is provided with a plurality of openings I! as best shown in Figure 4. By providing the openings I1, metal may flow from above the plate H into the cavity 3 to fill voids therein due to contraction of the metal upon cooling. The openings Il also provide vents through which hot gases may escape from the interior of the mold. In place of pouring metal into the space above the plate II, the use, of molten slag is contemplated.

It will be recalled that the trough structure 2 is initially held by friction within the mold 2. v By mounting the structure 2 in this manner, the position of such structure may be adjusted vertically within the mold. This feature is very important when the action that takes place as the casting cools is considered. When the metal is poured, a shell is formed around the inner surface of the mold due to the particles of metal being cooled by the mold. This shell in its initial stages of formation is very hot and after a period of time will begin to cool as heat is dissipated through the mold. As the shell cools it will contract in a vertical direction and the frictional mounting of the structure 2 enables such structure to move downwardly with the shell as it contracts. In like manner, the material over the top or separator plate I I will move down with the structure 2.

The use of the trough structure 2 and top II with the overlying layer of molten material will be found to materially reduce the formation of pipes in the casting within the mold I. Various theories may be advanced to explain the improved results from the use of such structure. However, it is believed apparent that the use of the overlying layer of molten material prevents the premature hardening of the upper portion of the casting which is recognized to be one of the principal causes of pipe formations. In addition, the mounting of the separator plate II by which such plate may move vertically with respect to the mold provides compensation for the shrinkage of the metal in the mold. The body of material overlying the separator disc II is available to exert a downward pressure thereagainst. 7

After the casting has cooled and the mold is removed therefrom, the material above the plate II may be removed by a sledge hammer. After removal of such material, the structure 2 and separator plate II is removed from the casting if it does not pull off with the overlying structure.

While. I have illustrated and described one 4 specific embodiment of my invention, it will be understood that this is merely by way of illustration and that various changes and modifications may be made within the contemplation of my invention and under the scope of the following claims.

I claim:

1. In an ingot casting mold, a member defining the upper end of a casting cavity in the mold and having a frictional fit with the sides of the mold so that it may move vertically with respect thereto, said member having an opening in the top thereof and parts cooperating with the sides of the mold to provide a trough extending around said opening into which metal may overflow from said opening, and a cover for said opening for defining a space thereabove which is separated from the metal below said member and into which molten material may be poured to prevent premature hardening of the cast metal below said member.

2. The invention claimed in claim 1 wherein said member moves vertically downwardly with and in response to shrinkage of the metal within said mold.

3. In an ingot casting. mold, a member operating to define the upper end of a mold cavity within the mold, said member having flanges frictionally engageable with the inner surface of the mold so that it may move vertically with respect thereto, said member having sides converging inwardly from said flanges and cooperating with the sides of the mold to define a trough extending around the inner surface of the mold,

' said member having an opening centrally thereof through which molten metal may overflow from said cavity into said annular trough, and a cover for positioning over said opening to define a space above said member which is separated from the metal below said opening and into which molten material may be poured to prevent the formation of pipe in the metal cast in said cavity.

4. The invention claimed in claim 3 wherein said cover is provided with diverging flanges having supporting engagement on said converging sides.

5. The invention claimed in claim 3 wherein said cover is constructed ofsheet metal having a protective covering of heat-resistant refractory material on opposite surfaces thereof.

6. In metal casting apparatus, a mold having a bottom and vertical sidewalls defining the bottom and sides of a mold cavity in which metal is to be cast, a member positioned in said mold and defining the top of said cavity, said member having vertically arranged flanges in frictional engagement with said side walls and side members projecting angularly inwardly from the top edges of said flanges to define a trough above said cavity and along said side walls, said side members having inner edgesdefining an opening centrally of said mold through which molten metal may overflow from said cavity into said trough, and a cover for closing said opening having flanges diverging angularly therefrom for supporting engagement on said side members, said diverging flanges being adapted to extend into the overflow metal in said trough and to be secured thereby to said side members, said cover and side members operating to define the bottom of a second cavity in said mold into which molten material may be poured to prevent the formation of a pipe in the casting in said first-named cavity.

7.- Casti g ppa atus as claimed in claim 6 wherein said member and cover are formed from sheet metal and are provided with coatings of heat-resistant refractory material on opposite surfaces of the sheet metal.

8. In apparatus of the character described, a partition comprising a hollow truncated structure formed of sheet metal having upper edges defining an opening and lower edges defining a second opening of larger area than said first opening, said lower edges having side members depending vertically therefrom for frictional supporting engagement with the sides of a mold, the outer surface of said truncated structure defining the inner surface of a trough around a mold when said depending side members are in frictional supporting engagement with the sides of a mold, the sheet metal forming said truncated structure having opposite surfaces thereof provided with a protective coating of heat-resistant refractory material.

9. In apparatus of the character described, a partition comprising a hollow truncated structure having upper edges defining an opening and lower edges defining a second opening of larger area than said first opening, said lower edges having side members depending vertically therefrom for frictional supporting engagement with the sides of amold, and a cover having angularly diverging side members for supporting engagement with the outer surface of said truncated structure, said cover member providing a closure for said first opening when said diverging side members are supported on the outer surface of said truncated structure, said truncated structure and said cover member being formed from sheet metal having opposite surfaces thereof provided with a protective coating of heat-resistant refractory material.

JOHN GOMBOSH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTe Number Name Date 1,431,803 Howard Oct. 10, 1922 2,127,277 Turner Aug. 16, 1938 2,390,500 Charman Dec. 11, 1945 FOREIGN PATENTS Number Country Date 386,860 Great Britain Jan. 26, 1933 456,933 Great Britain Nov. 1-8, 1935