US2913785A

US2913785A - Casting of ingots

Info

Publication number: US2913785A
Application number: US361016A
Authority: US
Inventors: Kramig Anna Louise
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-06-11
Filing date: 1953-06-11
Publication date: 1959-11-24
Anticipated expiration: 1976-11-24

Description

ov '24, 1959 R. E. KRAMIG, JR 2,913,785

CASTING OF INGOTS Filed June ll. 1953 ATTORNEYS.

Kramig ut'ix and trustee `of the estate of said Robert E: Kramig, Jr., deceased i i I r Application {une 11, 1953, Serial No.,;361,016v a 3 4 `ca{ims. (o. 22 139 v This invention relates to the casting of ingots of steel, iron and other metals. The invention is addressed particularly to the problem 'of preventing the adherence of an ingot castingtothesstool upon which the ingot mold is mounted, and to prevent deterioratin of the-stool by the molten metal during casting.: i i i The present' invention is directed particularly` to an improvement` in :the utilization of the invention which is shown in Robert E. Kramig, Jr., United States applica-` tion Serial No. 355,880,` filedzMay `18,` 1953, for "smirch Plate for'Ingot Moldsf' That application` discloses `a method of casting ingots `in which a layer or sheet or plate of resinous laminaterof densely compacted asbestos fibers is interposed between the upper surface 'of an ingot r stool and the lower surface of ;an ingot mold which is normally rested directly upon the stool. As disclosed in i full area-at the bottom of placed 'upon' the stool in such position that edgewise or 4 Z,9l3,785 Patented` Nov. 24, 1959 an ingot mold, but which is of sufiicient dimension, either -lengthwisely or widthwisely or along a diagonal line, to extend over the face of the stool and .present either edgewise or corner portions which-may be positioned beneath the stool so as to be held down thereby at those points. In conjunction with this afra'ngement, the invention preferably contemplates the utilization of a stool having a recess or cavity in its u`pper surface within which the smirch plate may be laid, the depth of the recess or cavity being such in relation to the thickness of thesmirch plate that the surface of the latter is flush or substantially flush with the surface of the former. In preparation for casting, therefore, a smirch plate of' the size indicated is laid in the cavity of the stool whichis adapted to receive it, then the mold is cornerwie= portions of'the plate are straddled respectively by'portions of the ingot mold, in order that the ingot mold may hold the smirch plate firmly in place against dislodgment or lifting by the molten metal being i poured.

the aforesaid 'application, it has been discovered that a" smirch plate ;of thisrnature is `capable' ofwithstanding the direct heat of the molten steel or iron which ispoured into the ingot mold, at least for a period of time sufricient to prevent the formation of a crater in .the` upper ingot to the metal of the stool.

In normal ingot founding, the molten metal is poured from a ladle directly into the ingot mold, the stream falling through a distance of six to ten feet, at least at the start of the pourwhenthe ingotmold'isempty. Also, the stream is of substantial-size; forexarnple,"an ingot weighing anywhere from six to -ten' ton's"wil1 be` poured completely in a matter of approximatelythirty-*to sixty seconds.` `It is apparent that these'cohditins createconsiderable turbulence of molten metal: within the ingot mold, particularly at the time ofthe initial impactof the falling stream of steel and driiig' the period when it is only partially filled.

When the smirch plate extends facially over the entire bottom area of the ingot mold, with its edges held down against the stool under the weight of the ingot mold itself, no dislodgment of the plate can occur by the metal which is being poured. However, a smirch plate of the type disclosed in the aforesaid patent application serves its greatest function at the start of the pour to prevent direct impact engagement of the hot molten metal against the metal of the stool, and this action occurs over a relatively localized target area rather than over the entire bottom area of the mold. Since a plate of resin laminate of densely compacted asbestos fibers is inherently a relatively expensive product to produce, in terms of square foot cost, the objective of this invention has been to provide means for the utilization of a smirch plate which is less in size than the entire cross sectional area of the bottom of the mold, but which may be used efiectively to protect the stool against the cratering action which would otherwise attend the onrush of the poured stream of molten metal, and which will also be efiective to prevent seizure or bonding of the ingot to the metal of the stool.

The present invention, brefiy, contemplates the utilization of a smirch plate which is less in facial area than the surface of the stool and to prevent seizure of .the cast,

to he-e mployed. For example, smirch plates of resin- 'The drawingsjillustrate a typical embodiment of the present invention, in which;

Figure lis a top plan view looking down at an ingot mold which is testing upon the upper surface of a stool which is' equipped with a smirch plate in accordance with the -present invention, and I 'Figure Zisa cross` sectional elevation taken on the line 2-2 of Figire l.

KIn the drawings, the stool is indicated generally at 1, the ingot mold at 2, both` of these elements being of `conventional size as will'be readily understood by those skilled in the art. The' stool, However, at its upper surface'3, is` provided with a cavity or recess 4, and a smirch plate 5 is laid within this cavity beneath the ingot mold. The smirch plate, as will be noted, is less in facial area than the opening at the mold within the bottom thereof, but the plate is so dirnensioned, in the embodime'nt showm that the dimensional on the plate diagonal is greater than the insidewidth of the mold at the bottom,

i so that 'corner portions 6--6 of the smirch plate may be straddled'by opposte edges of the mold when it is rested upon the stool. p

l he: recess 4 within the stool is dimensioned in conformity with the thickness of the smirch plate that is bonded asb estos laminat approximately of an inch thickmay be used, in which event the cavity is of substantially the same depth. The cavity 4 may be produced within the upper surface of the stool in the casting thereof, and, therefore, it permits the use of successive smirch plates of standard size in the successive casting of ingots on the stool.

Diagonal disposition of the smirch plate is shown in the drawings as a preferred embodiment because the least area of smirch plate is required in such an arrangement to produce satisfactory results. It is to be understood, however, that a square or oblong smirch plate may be utilized within a corresponding stool cavity for disposition underneath the mold in a direction transversely or longitudinally thereof. Such variations are not illustrated in the drawings because they are believed to be obvious modifications.

A'smirch plate upon which an ingot has been poured is substantially deteriorated by the molten metal and is not, therefore, conveniently reusable in the founding of a successive ingot. However, in the arrangement provided by the present invention, the amount of smirch plate material which is required is substantially reduced over what would be required for disposition over the entire bottom area of the ingot mold, and the cost, therefore, is substantially reduced. s

It will be noted that the surface areas of the stool between the inside edges of the ingot mold and the outer edges of the smirch plate are exposed directly to molten metal. However, if the stream of molten metal is targeted against the smirch plate, then these exposed metal surfaces' of the stool do not become cratered or seize to the ingot despite their direct engagement therewith; this result is probably obtained because the chilling efiect-of the stool metal is adequate to prevent adhesion or welding at areas outside the pouring stream of metal but would not be adequate at the direct point of impact of the stream with the stool.

In previous practice, when an ingot was cast upon a stool that had a crater already formed within it, the ingot, even if not stuck to the stool, would have upon its end a bulge of metal corresponding to the crater shape, and this would have to be removed at considerable labor cost and with waste of metal. In the practice of the present invention, as in the practice of the inveution dis- 'closed in the aforesaid application, an ingot is produced having a substantially smooth, even end which requires no attention prior to its use in the fabrication of shapes' or sheets;

Having described my invention', I claim:

l. Apparatus for use in the casting of ingots comprising a` stool havinga substantially flat upper surface and an ingot mold having a substantially fiat, open bottom adapted to rest upon the upper surface of said stool so that the stool constitutes a closure for the bottomof the mold, the said stool having a recess in its upper surface which is less in area than the open area of the) bottom of said mold,'but which has a greater dimension,

in at least one direction, than the dimension of' the mold.

in respectively the same direction, whereby the mold may be placed' upon the stool in position straddling the recess, r and a resinous laminate' of densely compacted asbestosv` fibers occupying substantially the entire area of said* recess and having' its upper surface substantially flush with the surface of said stool, the said' resinous laminate constituting a targetagainst which molten metal may be poured into said mold, to prevent cratering of the stool or seizure of the cast metal thereto.

2. In the combination of a stool having a substantially flat upper surface and an ingot mold having a substantially fiat, open bottom which is adapted to be rested upon the upper surface thereof, the improvement which x consists in the provision of a shallow recess in the upper;

surface of said' stool, which recess is of greater size along an axs in the plane' thereof than the corresponding dimen-f sion of the said mold taken along the same axis, butwhich recess is oflesser area than the area of the inside' opening at the bottom of saidmold, and a smirch plate' asbestos in densely compacted relation, disposed within the recess, the said smirch plate having its upper surface substantially flush with the s'urface of said stool lying beyond the boundaries of said recess, whereby the ingot mold may -be disposed in straddlng relation to said recess and plate therein at opposedpoints thereof, and thereby fasten the smirch plate fi'rrnly in said recess.

3. A stool which is adapted to su port ingot molds of predetermined size in the casting of ingots in said molds, the said stool having a substantially fiat upper surface' and having a substantially rectangular recess in its upper surface, the area of the said rectangle being less than the area of the inside opening' ofan ingot' mold'which is to be disposed upon said stool, but the said recess being greater in one of its coordinate dirensions than the corresponding dimension of the said ingot mold which is adapted to be rested upon said stool, whereby the ingot mold may be positioned upon' said stool to straddle opposed areas' of said recess', and a smirch plate disposed within said recess' and having its upper surface substantially flush with the' upper surface' of said stool in* areas lying' beyond the* said recess.

4. In the combination of a' stool having a substantially flat upper* surface and an ingot mold having a substantilly.flat,ropen bottom which is' adapted to be' rested upon' the upper surface' thredf the" improvement which consists' in` the provsion of a shallow recess' in the'uppersurface of said stool, which recess is" of greater size along an-axs in` the plane therof than the correspondng inside dimension ofthe said mold taken along the' same axis; but-which recess is of lesser area than the area of the in'si'de opening at the' bottom of said mold, and a smirch plate disposed within` the recess; the said smirch plate having its'u'pper surface substantially flush' with the surface of s'aid'stool' lying beyondthe boundaries' of'sid recess;` ;whereby the` ingotmold may be disposed in straddling relation to said' recess and plate therein at' opposed points thereof and. thereby fastenthe smirch plate r'ml'y in said recess.

References cited in the file of this patent UNITED STATES PATENTS