US2799067A - Bottom rings for hot tops - Google Patents

Description

July 16, 1957 G. A. PETERSON 2,799,067

BOTTOM RINGS FOR HOT TOPS 3 Sheets-Sheet Filed May 26.. 1950 A n w INVENTOR. asmv Hffrfswv BY my@ 47m/Veys July 16, 1957 G. A. PETERSON 2,799,067

BOTTOM RINGS FOR HOT TOPS Filed May 26, 1950 3 Sheets-Sheet 2 il" wn Mm HI u INVENTOR. l 60s74v A. Paraiso/v rrof/vsys July 16, 1957 G. A. PETERSON BoTToM RINGS FOR HOT Tops 5 Sheets-Sheei 3 Filed May 26, 1950 l JNVENTOR. 6057211@- ,4. PEI-Eisen fie. fo BY l ,4free/Veys United States Patent O BOTTOM RINGS FOR HOT TOPS Gustave A. Peterson, Chagrin Falls, Ohio, assignor to The Ferro Engineering Company, Cleveland, Ohio, a corporation of Ohio Application May 26, 1950, Serial No. 164,521

3 Claims. (Cl. 22-147) This invention relates to improvements in bottom rings for hot tops, that is single use molded and dried refractory rings for protecting the lower end of the metal casing of the hot top and adapted to separate from the hot top and remain on the ingot when the hot top is stripped therefrom. The application is a continuationin-part of my copending application Serial No. 145,373, filed February 21, 1950, now abandoned.

The invention provides bottom ring means of such character as to produce a tapered shoulder on the ingot, which it has long been realized would be avaluable improvement if it could be accomplished economically because of the beneficial effect upon the product, both as to quality and economy, when the ingot is rolled.

According to the present practice the bottom rings now commonly used are formed with an inner rim whichextends above the general upper surface of the ring, which rim acts as a locating means to prevent lateral movement of the ring on the casing. This rim also more or less completely fills the recess formed between the casing ledge and the overhanging semi-permanent lining supported on the ledge and it thus protects the inner surface of the bottom ledge of the casing.

In the present method of manufacturing these rings they are moldedwith the top of the ring in the bottom of the ring mold in order to form the rim referred to above. The bottom of the ring therefore becomes the top or strike-olf surface in the manufacturing process. This necessitates keeping the bottom of the ring flat in order to eliminate the necessity of employing removable pieces in the molding operation,together with dryers of special shapes which would be required during the subsequent manufacturing operations, all of which would increase the cost of the finished article to the point where they would be impractical. This flat bottom surface as now employed on these rings consequently produces a square or flat shoulder on the ingots on which the hot tops are used and this shoulder causes overlaps ,to form during the rolling of the ingots with a resultant loss in yield. A tapered shoulder on the ingot would help to prevent this overlapping during rolling 4and would Ythereby increase the yield. y

It has long been desirable therefore to change the shoulder of the ingot to a tapered or upwardly inclined surface rather than a square or horizontal surface as now employed. This could be accomplished by reversing the present method of manufacture so that the top surface of the ring would be the top or strike-off surface during the molding operation without adding to the cost of manufacture. However if this method were to be ernployed it would result in a ring with a flat upperpsurface with no rim projecting up from this surface to act as a tween the overhanging semi-permanent upper lining and 2,799,067 Patented July 16, 1957 ICC the bottom ring, but that solution of the problem presents important difficulties because such a thick body of wet patching material would require excessive time for drying and any moisture remaining in it would form steam when the hot metal struck the hot top and an explosion would result. The present invention preserves the aforesaid inner rim of the hot top bottom ring while providing an inwardly and upwardly inclined inner surface and without materially affecting the cost of manufacture.

One of the objects of the invention therefore is the provision of bottom ring means which will produce a tapered shoulder on the ingot and at a cost comparable to that of the conventional ring heretofore used.

Another object is the provision of a bottom ring assembly comprising two concentric rings Vjoined together at .intervals Aby integral tabs or other suitable means, which assembly may be manufactured, stored and shipped economically because of the relatively smaller height or thickness of the assembly as compared with the height or thickness of the assembly when expanded for use upon a hot top.

Still another object of the invention is the provision of a method of forming the ring assembly in a single molding operation.

Other objects and features of novelty will appear as I proceed with the description of those embodiments of the invention which, for the purposes of the present application I have illustrated in the accompanying drawings, in which:

Fig. 1 is a vertical sectional view of a hot top equipped with kthe ring means of the present invention in place upon an ingot.

Fig. 2 is a fragmental view of a portion of the same on a larger scale.

Fig. 3 is a schematic View of a portion of a ring manufacturing mold with fragments of a ring assembly in place therein.

Fig. 4 is a similar view showing a modification.

Fig.` 5 is a bottom plan view of a ring assembly constructed in accordance with the invention.

Fig. 6 is a crosssectional View of the same taken substantially on the line 6-6 of Fig. 5.

Fig. 7 is a View similar to Fig. 3 in which the two rings are joined by a Adifferent means and in which the inner ring is of somewhat different depth and taper than that of the outer ring.

Fig. 8 is a fragmental plan view of the same.

Figs. 9 and 1l are fragmental sectional views similar to Fig. 2 showing two different means for supporting the inner ring of Fig. 7 temporarily in the hot top, and

Fig. l0 is a detail View of one form of metal connector for joining the two rings together temporarily.

Referring toFigs. l and 2 of the drawing, 10 is a fragment of an ingot mold. Shown in operative relation with this mold there is a composite hot top embodying an iron casing which for practical manufacturing reasons may consist of two castings 11 and 12 secured together. At the lower end of casting 12 there is an inwardly extending ledge 13 the function of which is to support the upper semi-permanent lining 14 which may be composed of one or more courses of refractory lining blocks or bricks, as shown. A protective coating 15 of slurry may be applied to the inner surfaces of these blocks if desired.

The single use bottom ring means for protecting the lower and inner surfaces 'of the ledge 13 comprises an assembly of two preformed rigid refractory rings 16, 17, ring 16 having `a flat upper surface 1S which abuts against the lower surface of the ledge and ring 17 having an outer 4surface 19 which overlaps an inner surface 20 of ring 16 and covers substantially the, inner surface of the ledge 13.

The upper surface 21 of ring 17 extends beneath that portion of lining 14 which overhangs the ledge 13. The two rings have inclined inner surfaces 22 and 23 which preferably `are aligned when the ring assembly is mounted upon a hot top, that is to say in the case of a rectangular hot top the surfaces 22 and 23 on each side of the hot top will lie substantially in a single plane, and in the case of a circular hot top surfaces 22 and 23 will together form a truncated cone. When metal is poured into a hot top equipped with this ring assembly the entire shoulder of the ingot will be tapered as indicated in the drawing except for a narrow horizontal outer shoulder section at the base -of the taper.

As is conventional practice each hot top is serviced before being used. For this purpose the hot top is mounted in an inverted position in la supporting frame. As is well understood in the art, the upper lining 14 is not replaced for each ingot cast, but remains in place for a number `of ingots. The operator applies slurry coating 15 if such coating is used, and thereafter places patching material in the recess in the angle between the ledge and the upper lining. He then places the ring 16 on the ledge 13, `after which he presses the ring 17 into place which forces the patching material into the crevices between the surfaces 19 and 21 of the ring on the one hand and the inner surface of the ledge and the bottom surface of the lining 14 on the other hand, as well as between the two ring surfaces 19 and 20. The excess patching material is scraped off. A sheet metal wiper strip may then be placed lin position. The wiper strip is provided at intervals with slots to accommodate wire clips 26, the outer upper ends of which hook into steel eyelets 27 set into the casing section 12 and the lower ends of which are formed to extend around the lower and inner surfaces of ring 16 and may be extended to engage ring 17. When thus serviced the hot tops are set aside for a time sucient to permit the slurry and patching material to dry. Both rings being now held in place, the hot top may be returned to upright position without laffecting the mounting of the rings.

One of the important features of my invention is the construction of the two rings of such dimensions that the outer surfaces 19 yof the inner ring Will fit within the inner surfaces 20 of the outer ring so that the two rings may be manufactured as indicated in Figs. 5 and 6, Whereby they occupy a space of a height or thickness no greater than the height or thickness of one of them. By this means I effect an economy both in storage and shipping.

It 'is of course possible to mold each ring separately, put them together one inside the other and hold them in that condition against unintentional relative movement by metallic or other fastenings. However, I prefer not to do so, but on the contrary to form the two rings in a single mold and in a single molding operation and preferably mold them as an integral intermediate article of manufacture which can be handled and shipped as a unit but which can be readily separated into its two constituent parts upon its application to a hot top.

The preferred method of molding is illustrated sche- -matically in Fig. 3 where the ring m-old is indicated at 30 and the rings being molded therein at 16 and 17. Separating the upper portions of the mold cavities for the two rings there is a thin strip 31 of metal, cardboard or the like which is interrupted at intervals as indicated especially in Fig. 5 to form spaces into which the material of which the rings are molded may enter yand form integral tabs 32 connecting the two rings together and holding them together as an assembly or unitary article of manufacture. The strip 31 may be removed when the molded assembly has hardened, as indicated on the right hand side of Figs. 5 and 6. The strike-off surface S, Fig. 3, coincides with the at surfaces 18 and 21 of the rings 16 and 17.

When the rings are formed by the method just de` scribed and they are to be mounted on the inverted hot top, the assembly may be placed in position with the flat 'surface 1S of ring 16 resting upon the bottom surface of ledge 13. The operator may then insert a trowel edgewise in the slot between the rings and strike each tab 32 a sharp blow which will break the tabs and permit the ring 17 to be forced down through the patching material into the required position.

In Fig. 4 I have illustrated a modified molding method and means for holding the two rings together as a unitary intermediate product. In this figure the two rings 16 and 17 are shown as joined by a continuous web 35 of relatively less depth than the tabs 32 of Fig. 3. For this purpose the mold 36 includes a continuous portion 37 projecting upwardly part way along the surface 20' and the opposing surface 19 of the two ring parts of the assembly to be formed in the mold. Owing to the fact that the web 35 is much the weakest part of the molded object, this web may be broken readily to enable the two rings to be separated for mounting on the hot top. To effect this result a sharp blow may be struck against the inner ring part 17 -after the outer ring part 16 is supported upon the inverted ledge 13.

In Figs. 7 and 8 I have illustrated a step in my method as applied to the molding of a pair of rings indicated at 40 and 41 in a mold 39, these rings being formed of refractory material like that employed in the first described form of the invention and having a common strike-off surface S'. Their outer surfaces depart from the vertical only to the extent necessary to provide good draft. The height of ring 41 may be the same as that of ring 40, but preferably is of a less height as illustrated in order to be usable with a casing ledge 13', Fig. 9, of less depth than ledge 13 of Fig. 2.

The two rings have inner inclined surfaces 42 and 43. These inclined surfaces may be such as to align with each other when the bottom rings are mounted on the hot top, but they may also be of different inclinations as illustrated. When a pair of rings are to be molded the refractory in plastic form is placed in the mold cavities and the excess struck off in a comm-on plane S as indicated in Fig. 7, after which a series of short wires 44 are pla-ced in the composition so as to be lightly embedded when the refractory material hardens. These wires are spaced at intervals around the pair of rings and serve to unite the two rings temporarily for shipment, storage and handling. When the rings are to be assembled upon a hot top casing the same procedure is followed as in the case of the first described form of the invention, the wires 44 being readily broken out yof the hardened refractory of one or both rings when the outer ring is supported upon the inverted ledge 13', Fig. 9, and the inner ring is struck a series of sharp blows. The two rings may be held in place upon the hot top casing by means of wire clips such as the clips 26 of Fig. 2 or by other suitable means.

As indicated in Fig. 10 each of the short wire fastenings 45 may have a hook 46 at one end, so that the part of the fastening which is molded into ring 41 is securely anchored as compared with that in ring 40. When a pair of rings .so equipped is mounted on the inverted hot top the operator presses down the inner ring to force it into the patching material. The straight part of the wire fastening 45 is embedded to a slight extent only in ring 40 and hence pulls out of that ring when pressure is applied to the inner ring 41. When the inner ring is forced inwardly to the position in Fig. 9 the wires 45 strike against the corners 47 of the ledge and are bent into the form shown in Fig. 9. These wires therefore serve a double function, that is they hold the rings together until the rings are mounted on the hot top and they support the inner ring from the outer one when the hot top is returned to operative position and is mounted upon the ingot mold to perform its regular function. The outer ring 40 may be supported by wire clips 26 similar to the clips 2,6 of the first described form.

In accordance with the Fig. 11 construction the two rings 40 and 41 may be temporarily secured together by any of the means of Figs. 3, 4 and 7, the inner ring being broken loose from the outer one at the time the rings are mounted on the hot top. In this case however the inner ring is supported from the outer one by wire or metal ribbon clips l48 spaced apart at intervals. When the rings are being assembled on the hot top the latter is in an inverted position, its trunnions being mounted in a supporting metal frame specially constructed for the purpose. The ring 41 is rst put in place. Then the clips 48 are dropped into position over the ring 41. Thereafter the ring 40 is positioned over the ledge 13 and the projecting ends of the clips come in contact with surface 49 of ring 40. When the clips 26' have been hooked into the eyelets 27 and their opposite ends snapped over the outer ring 40 the two rings are secured to the casing 12 and the parts will remain in position when the ycasing is turned on its trunnions back into upright position.

It will be noted that in all of the described forms of the invention a taper surface is imparted to the ingot shoulder where the sinkhead joins the ingot proper. Whether the taper is of the same inclination throughout, as illustrated in Figs. 1 and 2, or has a plurality of inclinations as illustrated in Figs. 9 and 11 is of minor importance, since the advantages realized during the ingot rolling operations will be substantially the same.

Having thus described my invention, I claim:

1. An article of manufacture constituting an intermediate structure in the production of bottom ring means for hot tops, comprising a pair of non-metallic concentric refractory rigid rings, the upper surfaces of which are llat and ush, said rings having inner surfaces tapered upwardly, the outer transverse dimensions of the inner ring being slightly less than the corresponding inner transverse dimensions of the outer ring, said article having means disposed in the space between said rings interconnecting the rings and holding them against accidental relative displacement, said connecting means being adapted to be readily disabled by relative axial displacement of the rings.

2. A molded article of manufacture constituting an ntermediate structure in the production of bottom ring means for hot tops, comprising a pair of concentric nonmetallic refractory rigid rings having flat upper surfaces and inner surfaces tapered upwardly, the outer transverse dimensions of the inner ring being slightly less than the corresponding inner transverse dimensions of the outer ring, and spaced apart integral means holding the two rings together in assembled relation, said last named means being of sucient strength to hold the rings against accidental displacement during handling, storage and shipment.

3. A method of forming molded refractory bottom ring means for hot tops having an inner surface adapted to form an upwardly tapered shoulder on the ingot with which the hot top is used, which comprises molding in a single operation in upwardly open concentric inner and outer mold Icavities concentric inner and outer nonmetallic refractory rings having strike-off faces in a common plane and inner upwardly tapered surfaces, and employing in the mold means for bridging the two ring cavities at spacedintervals, whereby the resultant rings when hardened are connected at spaced intervals and whereby they may be broken apart and displaced axially to overlapping relation to cause said strike-off surfaces to assume stepped relation and said tapered surfaces to come into substantial alignment.

References Cited in the le of this patent UNITED STATES PATENTS 433,079 Halsey et al July 29, 1890 625,756 Glover May 30, 1899 1,291,390 Broadbent Jan. 14, 1919 1,358,435 Frank Nov. 9, 1920 1,503,122 Frank July 29, 1924 1,692,433 Barkschat Nov. 20, 1928 1,921,729 Charman Aug. 8, 1933 1,997,677 Charman Apr. 16, 1935 2,097,314 Wales Oct. 26, 1937 2,181,814 Knapp Nov. 28, 1939 2,335,622 Turner Nov. 30, 1943 2,572,452 Daley Oct. 23, 1951 2,574,815 Charman Nov. 13, 1951 FOREIGN PATENTS 532,156 Great Britain Jan. 17, 1941

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