US2574815A - Bottom ring for hot tops and mounting means therefor - Google Patents

Description

Nov. 13, 1951 w. M. CHARMAN 2,574,315 l BOTTOM RING FOR HOT. TOPS AND MOUNTING MEANS THEREFOR Filed April 1, 1949 INVENToR. ma nsf M, {WMA/v ,66.5 O BY m @MW/m g nvr/vsn? Patented Nov. 13, 1951 o'r'roM Emo Fon Ho'r 'roes AND Manna ma MEANS 'rnanaroa Walter M. Charman,l Shaker Heights, Ghia ApplicationApril 1, 1949, Serial No. 85,015

Claims. i l

This invention relates to improvements in bottom rings and mounting means therefor. The invention has to do with composite hot tops, that is hot tops comprising metal casings and refractory linings therefor, by means of which a pool of molten metal is maintained above the ingot mold for filling the pipe cavity which forms as the metal in the mold cools. A hot top of this character is disclosed in the prior art, for example in my previous PatentA 2,258,483 dated October'l, 1941.

In order to protect the lower end of the casing the hot top oi the prlorart includes a bottom ring of refractory material temporarily supported upon the metal casing. which ring is. intended for a single use and remains behind on the ingot when the hot top is stripped therefrom. Such a. ring is conventionally formed with. an inner rim which extends above the general upper surface of' the ring. and byengagement with the ledge prevents lateral movement of the ring such as tends to occur occasionally when the ring strikes the mold as the hot top is being lowered thereinto.

It has long been appreciated that bottom rings with tapered inner walls would be desirable since such a ring would form a beveled shoulder on the ingot. Heretofore it has not been practical however to make bottom rings with tapered inner surfaces because of prohibitive costs in the molding of such rings.

An object of the present invention therefore is the provision of a bottom ring with a tapered inner surface which may be produced readily and economically by ordinary molding operations.

Another object is the provision of means for preventing lateral dislocation of such a ring rela tive to the hot top casing.

Other objects and features of novelty' will ap pear as I proceed with the description of that embodiment of the invention which,v for the purposes of the present application, I have illustrated in the accompanying drawing. in which Fig. 1 is an elevational view on a small scale of an ingot formed in a big end up mold provided with acomposite hot top having a tapered bottom ring in accordance with my invention.

Fig. 2 is a bottom plan view of my improved hot top. a portion of the bottom ring being broken awa-Y.

Fig. 3 is a fragmental sectional view taken substantially on the line l--l of Fis. 2 but on -a larger scale.

Fig. 4 is a fragmental elevational view. partly Fig.. 5y is a i'ragmenta bottom plan view oi av modi'iication.

Fig. 61 is a fragmental elevational view ofv they same', and v Fig. 'I is a fragmental vertical sectional view showing a prior art construction.

InI the drawing the metal casing of a composite l hot top is` shown at` ii). It has an inwardly exends which are adapted to be snapped into sockets il formed in the casing wall.

The lower surface oi' ledge il is generally dat. as indicated at i3. At opposed points it is provided with downwardly extending projections or pads i9. These pads may ber of the order of onehalf inch or less in thickness. In. the smaller sizes of hot tops two such pads are suiiicient. A larger number may be desirable for larger size hot tops. They may be positioned at opposed corners of the ledge or at points other than the corners if desired. The bottom ring is formed with indentatlons 20 to receive the pads i9'. In the molding of the bottom ring the fiat upper surface i4 is the strike-ofi surface. The indentations may be formed' byV placing loose pieces in the mold beneath the strike-oir' surface, by cutting the green ring while still soft. or by grinding or cutting the hard finished' refractory. It is not necessary that there be a close ht between the pads and the indentations, for the clearances can be filled with slurry when the ring is mounted upon the inverted hot top. A sheet metal wiperi strip a' of conventional form may be interposed between ring iE and bottom ledge ii.

Figs. 5 and 6 show a pad 2i of slightly different form which may be employed at each of the corners of a rectangular hot top or at three or moreY evenly spacedv points oi a circular hot top.

When the bottom .ring il has been placed upon the inverted casing it and the clips i6 put in position to attach the ring to the casing the operator trowels a heat resistant slurry or grout 22 into the annular space between the overhanging edge of the lining l2 and the upper surface o! the ring I3 to fill and seal this joint and provide a smooth inner surface between the upper 3 lining and the bottom ring. Thereafter the hot wp is subjected to a drying temperature to expel moisture from the grout and harden it.

In Fig. 7 I have illustrated a conventional bottom ring construction of the prior art, 28 being the bottom ledge of a metal casing, 24 being the semipermanent lining resting upon the ledge and 25 being the bottom ring. When such a ring is molded the bottom surface 26 is the strike-off surface. 21 is the upwardly projecting rim on the bottom ring which approximately meets the lower edge of the upper lining, any clearance being taken up with slurry or high temperature cement. In the majority of cases the handling of the hot top does not tend to loosen the loot-V tcm ring, but frequently mishandling occurs, causing the hot top assembly as it is being set into the mold to swing against the mold wall as the crane man and his helpers lower it into operating position. The swinging hot top because of its mass possesses considerable energy and if itis arrested by the ring striking the mold a tendency to displace the ring relative to the hot top casing is experienced. The rim 21 of the Fig. '7 construction in connection with the cement or grout behind it prevents any dislocation of the ring under such circumstances.

The ring I3 of the present invention, having a flat upper surface. would slide laterally across the fiat lower surface of the ledge if it were not for the pads i9 or 2i. These pads in cooperation with the indentaticns in the bottom ring effectively prevent such accidental lateral dislocation of the ring.

Having thus described my invention, I claim:

1. In a composite hot top, a metal casing having a generally fiat lower surface, a plurality of spaced projections depending from said fiat surface. a refractory heat insulating bottom ring with a generally fiat upper surface engaging the lower surface of said casing and an upwardly tapered inner surface, and provided with indentations to receive said depending projections, and means for supporting said bottom ring from said casing.

2. In a composite hot top, a refractory metal casing having an inturned bottom ledge for supporting a semipermanent refractory heat insulating lining, said ledge having a generally fiat lower surface. projections extending downwardly from said flat surface at two opposed corners of said ledge, a refractory heat insulating bottom ring with a generally fiat upper surface engaging the at lower surface of said ledge and an upwardly tapered inner surface, and provided with indentationa to receive said depending projections. and means for supporting said bottom ring from said casing.

3. In a composite hot top having a metal casing with an inturned bottom ledge and a semipermanent refractory heat insulating lining supported by and overhanging said ledge, said ledge having a generally flat lower surface, projections extending downwardly from said flat surface at opposed points of said ledge, a refractory heat insulating bottom ring with a generally fiat upper surface engaging the fiat lower surface of said ledge and an upwardly tapered inner surface and provided with indentations to receive said depending projections, means for supporting said bottom ring from said casing, and a dried grout ring seal filling the space between the overhanging portion of said semipermanent lining and said bottom ring.

4. A molded refractory heat insulating `bottom ring for use upon a hot top casing, said ring having an upwardly and inwardly inclined inner surface and a generally flat upper surface, the latter surface being provided with a plurality of spaced indentations adapted to receive casing projections for holding the ring against lateral displacement.

5. In a composite hot top. a metal casing having an inturned bottom ledge for supporting a semipermanent refractory heat insulating lining, said ledge having a generally flat lower surface, projections extending downwardly from said fiat surface, a refractory heat insulating bottom ring with a generally fiat upper surface engaging the flat lower surface of said ledge and an upwardly tapered inner surface, and provided with indentations to receive said depending projections, and means for supporting said bottom ring from said casing.

WALTER M. CHARMAN.

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

UNITED STATES PATENTS Number Name Date 1,921,731 Charman Aug. 8, 1933 1,931,769 Newton Oct. 24, 1933 2,029,058 Charman Jan. 28, 1936 2,030,199 Charman Feb. 11, 1936 2,099,342 Lemmerman Nov. 16, 1937 2,420,003 Miller May 6, 1947 2,462,260 Garms Feb. 22. 1949

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