US3809355A - Hot top maintaining system for an ingot mold - Google Patents

Abstract

The improved hot top maintaining system permits disposable hot top sideboards to extend above the ingot mold. A chill wedge is used in combination with a wedge plate positioned within converging grooves of adjacent sideboards. The chill wedge, after insertion, is flush against the wedge plate and the adjacent sideboards and provides a chill zone at the sideboard juncture so as to immediately solidify the metal and retain it within the hop top system.

Description

United States Patent Rocher [451 May 7,1974

[ HOT TOP MAINTAINING SYSTEM FOR AN INGOT MOLD [75] Inventor: George Rocher, Pittsburgh, Pa.

[73] Assignee: Metallurgical Exoproducts Corporation, McKees Rocks, Pa.

[22] Filed: Sept. 25, 1972 [21] Appl. No.: 291,655

[52] U.S. Cl. 249/106, 249/197 [51] Int. Cl B22d 7/10 [58] Field of Search 249/106, 197-202;

[56] References Cited UNITED STATES PATENTS 3,178,783 4/1965 Ednell et al 249/106 3,421,731 1/1969 Koch et al. 249/197 Primary Examiner-Robert D. Baldwin Attorney, Agent, or Firm-Webb, Burden, Robinson & Webb 7 57 ABSTRACT The improved hot top maintaining system permits disposable hot top sideboards to extend above the ingot mold. A chill wedge is used in combination with a wedge plate positioned within converging grooves of adjacent Sideboards. The chill wedge, after insertion, is flush against the wedge plate and the adjacent sideboards and provides a chill zone at the sideboard juncture so as to immediately solidify the metal and retain it within the hop top system.

4 Claims, 7 Drawing Figures HOT TOP MAINTAINING SYSTEM FOR AN INGOT MOLD FIELD OF THE INVENTION My invention relates to hot top systems and, more DESCRIPTION OF THE PRIOR ART Hot top systems employed in the teeming of killed steel ingots and the like are normally of the disposable type which comprises sideboards held in place within the ingot mold interior by various clips, wedges, rods or the securing means or are of the permanent type in which a refractory lined metal casing is positioned atop of the ingot mold. The permanent hot top system normally includes refractory brick, but various forms of replaceable refractory linings have been suggested.

In order for any hot top system to be effective, it must be substantially filled with molten metal to provide an adequate reservoir of molten metal. Generally, the hot top volume varies from to percent of the total volume depending on the particular system. Therefore, for a given mold size, a known and reoccurring ingot weight is obtained. However, it is often advantageous to alter the ingot weight for a given mold size to provide particular slab cuts or bloom cuts necessary to make an ordered weight. Without flexibility for a given mold size, good steel is often discarded to make the necessary weight, thereby substantially reducing the overall yield of the product. In practice it is often necessary to provide 5,000 pounds of steel to obtain a 1,000 pound larger slab simply because there is no flexibility for a given mold size and a larger mold size must be used.

Steel manufacturers occasionally attempt to set disposable hot top systems well into the ingot molds where a lighter than normal weight is obtained from a given mold size. This, however, increases the likelihood of hot top floaters since it is difficult to secure hot top boards any appreciable distance below the top surface of the ingot mold.

SUMMARY OF, THE INVENTION My invention increases the r ange of ingot weights from a given mold size by providing a hot top maintaining system which can be set into the ingot mold in known fashion or can be retained in place so that the upper portion of the hot top is above the ingot mold upper surface. This then maximizes ingot to slab or bloom yields and gives the steel provider a new range of flexibility. In addition, my hot top maintaining system decreases the likelihood of hot top floaters" by adding additional retaining means to an already acceptable hot top maintaining system. My hot top maintaining system can be easily set in place by the worker irrespective of the intended position of the hot top system in relation to the ingot mold.

My invention is an addition to the hot top maintaining system described in US. Pat. No. 3,421,731 of which I am a co-inventor. In the system described in the aforementioned United States patent, each sideboard has a pair of inclined grooves on the inner face near the ends thereof. Adjacent sideboards define converging grooves toward the mold corner and accommodate a wedge means to retain the sideboards against the ingot mold walls. I have added to that system a chill wedge formed of two intesecting faces, each having a downwardly inclined distal edge to engage the wedge means while each face of the chill wedge is flush against the sideboard. The chill wedge is constructed to assure the solidification of the metal at the comer formed by the intersecting faces which is in alignment with the corner formed by the adjacent sideboards.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevation of a hot top sideboard;

FIG. 2 is an isometric through an ingot mold corner showing the construction of my hot top maintaining system;

FIG. 3 is an isometric of my chill wedge;

FIG. 4 is a section taken along section lines IVIV of FIG. 1;

FIG. 5 is an isometric showing the support structure for my hot top maintaining system;

FIG. 6 is an isometric of a modified chill wedge; and

FIG. 7 is an isometric of an ingot mold corner showing a modified form of my hot top maintaining system.

DESCRIFT ION OF THE PREFERRED EMBODIMENTS The hot top maintaining system, generally designated 10, cooperates with an ingot mold 11 to provide a reservoir of liquid metal which fills the cavity formed during solidification of certain metals such as killed steels. The ingot mold 11 is normally four sided and, therefore, four sideboards 12 are normally employed to form the hot top maintaining system 10. The sideboards are t of the disposable preformed type and the composition thereof does not form a part of the invention.

Each sideboard 12 has a pair of grooves 14 formed on the inward face near the opposing ends of the sideboard 12. These grooves 14 are outwardly inclined with regard to each other, FIG. 1. Specifically, the distance designated A between the top edge of the sideboard and the top of the groove 14 is greater than the distance designated B between the bottom edge of the sideboard and the bottom of the groove 14. The depth of the groove 14 may also be decreased along the length of the groove to increase the wedging effect, but such a change in depth is not mandatory.

End adjacent sideboards 12 provide adjacent grooves 14 which have a resultant inclination so as to converge downwardly toward the ingot mold corner, FIG. 2. In assembled relationship, a wedge plate 16 is inserted in the adjacent grooves 14 of end adjacent sideboards 12 so that increasing outward force is exerted upon the sideboards 14 as the wedge plates 16 are moved downwardly along the grooves 14. This wedging action forces the sideboards 12 against the respective walls of ingot mold 1 l. The sideboards 12 are positioned so that their upper portion is above the top surface 13 of the ingot mold 11, FIG. 2. A space 15 is formed by the adjacent sideboards 12 in the corner positions. This space 15 is aligned with and closed off by the mold corner below the upper mold surface 13 and is unrestrained above the ingot mold.

A chill wedge 18 is formed of two perpendicularly intersecting faces 23 and 24, each having its distal edge 20 inclined inwardly at approximately the same angle as the angle of convergence of the Wedge plate 16 when in place, FIG. 3. The purpose of the chill plate 18 is to assure solidification of the molten metal so that it will not escape through the space and escape along the upper surface 13 of the ingot mold 11. For this purpose the chill plate faces 23 and 24 can be made of a relatively thick steel but since the real need for the chill 'zone is in the corners formed by the end adjacent sideboards, I have found that a'steel rod can be secured along the intersection formed by the two faces, thus allowing a relatively thin sheet steel to be used for faces 23 and 24. A three-fourths inch steel rod spot welded on the interior corners of a 16 gauge mild steel chill plate has proven more than adequate.

The distal edges engage the wedge plate 16 while the faces 23 and 24 are flush with the end adjacent sideboards 12, thereby creating an additional wedging action which forces the sideboards 12 outward against the mold walls, FIGS. 2 and 4. The interior corner of the chill plate 18,-including rod 19 positioned therealong, is in alignment with the space 15 thereby providing sufficient chill to cause immediate solidification and prevent molten metal spillage out of the space 15.

In order to facilitate supporting the sideboards 12 while the wedges 16 are being installed, rods 17 are molded into the sideboard so as to extend out of the ends thereof. Other support structures, both internal and external, can be employed but rods add to the reinforcement of the sideboard itself. These rods'l7 of end adjacent sideboards 12 rest on a wooden block 20 which is positioned in the corner along the upper surface 13 of ingot mold 11, FIG. 5. To assure a perfect alignment of the sideboards, the block 20 has a slightly elevated section 22 so as to avoid interference between rods 17 of adjacent sideboards 12. As a practical matter, a simple block of wood can be employed and the rods 17 of adjacent sideboards 12 can merely rest on one another since the total wedging action is sufficient to maintain the hot top system in place. I

A chill wedge 25 can also be employed in which a metal fin 27 extends rearwardly from the exterior surface of the corner of the intersecting faces 33 and 34, FIG. 6. The fm 27 extends into the space formed by the end adjacent sideboards. The purpose of the fin 27 is to increase the chilling effect in the corner and not to totally fill the aforementioned space.

The sideboards may be designed to include the support means as an integral part of the board itself. Sideboards 29 are molded to include an enlarged upper section 30 which provides a shoulder 31 which rests on the upper surface 13 of ingot mold 11 to facilitate installation of wedge plate 16 into the grooves 14 of the sideboards 29, FIG. 7. Chill wedge 25 having a rearward fin 27 positioned in the space between sideboards 29 is illustrated in this particular embodiment. In addition to providing the support means for installation of the hot top maintaining system 10, the enlarged upper section 30 provides additional insulation for the hot top in the area surrounding the hot top system above the ingot mold.

I claim:

1. A hot top system for an ingot mold comprising:

A. a plurality of end adjacent sideboards each having a pair of outwardly inclined grooves formed on the inward face near the ends thereof;

B. means for supporting the sideboards against the ingot mold walls so that the upper portion of the sideboards extend above the ingot mold;

C. a wedge plate insertable into adjacent grooves of end adjacent sideboards so as to converge downwardly toward the ingot mold corner and retain the sideboards against the ingot mold walls and D. a chill wedge having perpendicular intersecting faces, each face inclined downwardly along the distal edge thereof to matingly engage the converging wedge plate, each face being flush against the adjacent sideboard and the intersection of the faces being aligned with a corner formed by the end ad jacent sideboards, said wedge plate and chill wedge extending below the ingot top mold.

2. The hot top system of claim 1 wherein the sideboards include an enlarged shouldered upper portion resting atop the ingot mold walls to form the supporting means for the sideboards.

3. The hot top system of claim 1 wherein support bars extend out of the sideboard ends.

4. The hot top system of claim 3 wherein the supporting means comprises blocks positioned atop of the ingot mold corners so as to support the bars extending out of the sideboard ends.

Claims (4)

1. A hot top system for an ingot mold comprising: A. a plurality of end adjacent sideboards each having a pair of outwardly inclined grooves formed on the inward face near the ends thereof; B. means for supporting the sideboards against the ingot mold walls so that the upper portion of the sideboards extend above the ingot mold; C. a wedge plate insertable into adjacent grooves of end adjacent sideboards so as to converge downwardly toward the ingot mold corner and retain the sideboards against the ingot mold walls; and D. a chill wedge having perpendicular intersecting faces, each face inclined downwardly along the distal edge thereof to matingly engage the converging wedge plate, each face being flush against the adjacent sideboard and the intersection of the faces being aligned with a corner formed by the end adjacent sideboards, said wedge plate and chill wedge extending below the ingot top mold.

2. The hot top system of claim 1 wherein the sideboards include an enlarged shouldered upper portion resting atop the ingot mold walls to form the supporting means for the sideboards.

3. The hot top system of claim 1 wherein support bars extend out of the sideboard ends.

4. The hot top system of claim 3 wherein the supporting means comprises blocks positioned atop of the ingot mold corners so as to support the bars extending out of the sideboard ends.

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