US3265347A

US3265347A - Hot top

Info

Publication number: US3265347A
Application number: US393696A
Authority: US
Inventors: Wickstrom Arthur Stanley
Original assignee: Sandvik AB
Current assignee: Santrade Ltd
Priority date: 1963-09-02
Filing date: 1964-09-01
Publication date: 1966-08-09
Anticipated expiration: 1983-08-09
Also published as: GB1072804A

Description

A118 9, 1966 Afs. wlcKsTRM v 3,265,347

HOT TOP Filed Sept. 1. 1964 3 Sheets-Sheet l l Fig. I

A. s. wlcKsTRM HOT TOP Filed Sept. 1, 1964 3 Sheets-Sheet 2 f 6 //N///// //H /H Fig Aug. 9, 1966 A. s. wlcKsTRM HOT TOP 5 Sheets-Sheet 3 Filed Sept. l, 1964 United States Patent 3,265,347 HST TGP Arthur Stanley Wickstrm, Sandvikeu, Sweden, assignor to Sandvikens lernverlrs Aktiebolag, Sandvilren, Sweden, a corporation of Sweden Filed Sept. 1, 1964, Ser. No. 393,696 Claims priority, application Sweden, Sept. 2, 1963, 9,553/63 8 Claims. (Cl. 249-106) The present invention relates to a hot top of the type which comprises a number of separate slabs mounted along the upper part of the inner wal-ls of an ingot mold. One purpose of the invention is to obtain a suitable tapering of the sink head of the ingot for the subsequent rolling procedure. Another purpose is to facilitate the mounting of the hot top. Still another purpose is to facilitate the stripping of the ingot from the mold.

In previous types of hot tops built of slabs, either all slabs lhave been substantially vertical or all slabs have been inclined towards the center of the mold. In the present hot top there are two opposite slabs which are substantially vertical and have at least partly inclined end edges, two other opposite slabs being at least partly inclined and resting on said inclined edges. The invention is useful in all types of ingot lmolds and especially in such ingot molds which have an oblong, usually rectangular, horizontal cross section. Ingots of this type are used when rolling -sheet material, and it has been found suitable to apply the invention to the mold in such a way that the short end slabs of the hot top are substantially vertical, the longitudinal slabs being inclined and resting on the inclined edges of the short end slabs. This gives a better utilization of the upper end of the ingot, improving the quality of the rolled product and increasing the yield from the ingot.

The hot top according to the invention can be used in ingot molds having walls which are substantially vertical and have a straight vertical section line, thus eliminating the necessity of providing the ingot mold with shoulders for supporting the lower edges of the hot top slabs.

Other details and purposes of the invention appear from the following specification and the accompanying drawings of which: f

FIG. 1 is a vertical cross section on the line 1-1 in FIG. 2-and shows the upper part of an ingot mold and a hot top according to the invention mounted therein.

FIG. 2 is a vertical section on the line 2-2 in FIG. 1.

FIG. 3 is a top elevational view of the ingot mold shown in FIGS. 1 and 2.

FIG. 4 is a cross section similar to the one in FIG. 1 showing another embodiment of the hot top.

FIG. 5 is a cross section similar to the one in FIGS. 1 and 4 showing a third embodiment of the invention.

FIG. 6 is a side elevational view on the line 6-6 in FIG. 4 and shows a strap device for locking the hot top on the mold.

FIG. 7 is a perspective view of a special embodiment of the ingot mold.

FIG. 8 shows alternative embodiments of support constructions for the hot top as shown in FIG. 1.

FIGS. 1-3 show an ingot mold 10 having a rectangular horizontal lcross section. The section can be modied without deviating from the inventive idea. The walls can for instance be corrugated, so that the horizontal section is wave-shaped, or the walls can be placed at an obtuse angle to each other, as for instance in an octagonal mold. In the illustrated mold is shown a hot top consisting of two

end slabs

11, 11a, one at each short end wall of the mold and two longitudinal slabs 12, 12a, one at each longitudinal side of the mold. The

short end slabs

11, 11a are similar to each other, so the description is confined "ice to the slab 11 only. The slab is substantially vertical and rests in the sideward direction against the wall of the mold. It is hung up on the top surface of the mold by means of a flange 16 which is integral with the slab and which has its lower side inclined, so that the slab rests on the outer edge 17 of the flange 1'6. This causes the slab 11 to -pivot by its own weight around the edge 17, so that the -lower edge of the slab, having ,a tightening ridge 15, is urged aga-inst the wall of the mold. The end edges 18 of the slab are inclined upwardly and inwardly.

T-he longitudinal slabs 12, 12a are also similar to each other and only the slab 12 is described. The slab rests at both ends on the inclined surfaces 18 of the short end slabs a-nd abuts at its bottom edge against the long side wall of the mold. The slab has a beveling 19 matching the said wall in order to obtain a tight contact and prevent molten metal from leaking through. The top side of the slab is supported by a support piece consisting of a plate 20 which is strengthened by a ilange iron 21 i-n order to prevent bending of the plate. The slab 12 can be attached to the plate 20 by, for instance, glueing or riveting in order to prevent sagging of the slab under its own weight.

In case the mold has another cross section than the one shown and has for instance six or eight sides, the above embodiment can be modiiied, maintaining the principle that two opposite slabs or groups of slabs are substantially ver-tical and have inclined end edges and the intermediate slabs or groups of slabs are inclined and rest on the inclined edges of the iirst mentioned slabs.

In FIG. 4 is shown an embodiment having

longitudinal slabs

22, 22a with a curved vertical section. The end edges of the short end .slabs must of course be curved to the same shape in order to obtain a tight contact between the longitudinal slabs and the short end slabs. The longitudinal `slabs are at their top side supported by support pieces formed by curved sheets 24, 24a. Because of the curved shape the sheets will be rigid enough without extra. flange bars like the bars 21 in FIG. 1.

In FIG. 5 is shown a third embodiment. The

longitudinal slabs

25, 25a have an angular cross section, the top portion being substantially vertical and the bottom portion being inclined. The end edges of the short end slabs have of course a similar shape, the upper part of said edges being substantially vertical and the lower part inclined. The top side of the longitudinal slabs is, in the same way as before, supported by matching support pieces formed by

sheets

27, 27a. The

slabs

25, 25a can be divided by

joints

50, 50a in order to ensure a good tightening contact at the Ilonger edges of the longitudinal slabs as well as at the contact surfaces between the 1ongitudinal slabs and the short end slabs.

In order to prevent the longitudinal slabs and their support pieces being moved upwardly by the pressure from the cast metal a special locking device can be used. In

FIG. 5 is shown a locking device consisting of

locking pieces

33, 33a, which suitably can be somewhat wedge shaped and provided with

teeth

34, 34a preventing the pieces from being lmoved upwardly. The

pieces

33, 33a are inserted at the short ends of the hot top.

In FIGS. 4 and 6 is shown another type of locking device. The longitudinal plates have, `at their tops,

longitudinal bars

28 and 28a, fastened thereto, for instance by welding. Said bars extend to the outside of the mold and are urged downwardly by Aa strap `device on each side ofthe mold comprising a transverse bar 29 resting on the ends of the bars 2S and 28a. The transverse bar 29 is provided with a loop shaped bar 30l having slits in which a wedge 3 1 is inserted. The top side of the wedge acts on the lower side of a knob 32 on the mold wall which usually is used for lifting the mold. By means of the wedge 31 the strap device 30v is used to urge the

bars

28, 28a downwardly thus holding the

longitudinal slabs

22, 22a -r-rnly in their desired position.

Still another possibil-ity for preventing the longitudinal slabs from being urged upwardly is to ll the space 35 (FIG. 5) between the

support plates

27, 27a and the mold by a ller material (not shown). Instead of a filler material plus the support plates `a unitary support body can be used. In the -left hand part of FIG. 8 is shown a solid support body 45 and in the right hand part a hollow support body 47. In order to prevent the support bodies from resting too heavily on the slabs of the hot top, the support bodies can be provided with anges (not shown) resting on the top side of the ingot mold. The support body 45 can be made of cast iron, concrete, brick or some other suitable material. The support body 47 can be made of for instance steel sheet.

A special advantage with the present hot top is that the spaces between the mold and the lsink head formed by the inclined support plates make the sink head accessible by stripping tongs for removing the ingot from the mold. In order to improve this accessibility the mold can be provided with

openings

40, 40a or 41, 41a (the latter shown in broken lines) in the upper part of the long side walls as shown in FIG. 7.

The slabs of the hot top can suitably consist of a heat insulating material having a sucient mechanical strength for being mounted in the way shown and described above. A suitable material is a composition comprising a major quantity of a line grained refractory material as quartz or olivine, and minor quantities of an organic fibrous material as paper pulp and `a binder lfor instance a synthetic resin glue, with a possible addition of a minor quantity of a fibrous refractory material as -for ins-tance asbestos as disclosed, for instance, in Davidson U.S. Patent No. 3,072,981 dated Ian. 15, 1963. This composition has a superior heat insulation and can be ysupported by a -good heat conductor, as for instance a support body 45 made of cast iron, and yet provide a sufficient heat insulation. It may, however, 'be expedient to use a heat insulating material in the support body also in order `to still more improve the heat insulation.

rl`he present hot top can be situated at an arbitrary level within the mold. The short end slabs can be hung up by flanges as shown in FIG. 2, the flanges being placed at the desired level, or by other suspension means as for instance steel strips or wires. The longitudinal slabs are thereafter placed on the inclined edges of the short end slabs.

I claim:

1. A hotV top mold combination comprising an ingot mold and a hot top consisting of four slabs positioned around the upper part of said mold adjacent to the sides of the ingot mold, two opposed slabs being substantially vertically disposed close to their adjacent sides and conforming to their surface shape and having at least partly upwardly converging end edges, the other two slabs being at least partly inclined upwardly and away from their adjacent sides and resting on said end edges, the lower edges of said inclined slabs conforming to the shape of the adjacent sides of the `ingot mold and abutting against said sides, .and support pieces secured to and covering the outer surfaces of said inclined slabs and serving to support said slabs against breakage and against movement out of contact with -said end edges by the pressure of molten metal in said mold.

2. Hot top-mold combination according to claim 1 in which said substantially vertical slabs each has a-n integral tightening ridge protruding from the lower edge of the slab toward the mold wall.

3. Hot top-mold combination according to claim 1in which the ingot mold has ,an oblong shape and said substantially vertical slabs are placed at the short sides of the mold while said inclined slabs are placed at the long sides of the mold.

4. Hot top-mold combination according to claim 1 in which the said linclined slabs .and `the matching support pieces each has va curved vertical cross section.

5. Hot top-mold combination according to claim 1 in which the said inclined slabs and the matching support pieces each has an angular vertical cross section.

6. Hot top-mold combination according to claim 1 in which the said support pieces each lls the space between an inclined slab and the adjacent wall of the ingot mold.

7. Hot top-mold combination according to claim 1 comprising strap devices 'for preventing the said support pieces from being moved upwardly by the cast metal.

8. Hot top-mold combination as dened in claim 1 in which the mold has openings in its upper edges adjacent to said inclined slabs.

References Cited by the Examiner UNITED STATES PATENTS 1,258,209 3/1918 Gathmann 249-106 1,738,209 12/ 1929 Rowe 249--202 1,830,479 11/ 1931 Mueller 249-4200 2,465,977 3/ 1949 Marburg 249-19-7 3,208,116 9/ 1965 Gathmann 249-201 X l. SPENCER OVERHOLSER, Primary Examiner. E. MAR, Assistant Examiner.

Claims

1. A HOT TOP MOLD COMBINATION COMPRISING AN INGOT MOLD AND A HOT TOP CONSISTING OF FOUR SLABS POSITIONED AROUND THE UPPER PART OF SAID MOLD ADJACENT TO THE SIDES OF THE INGOT MOLD, TWO OPPOSED SLABS BEING SUBSTANTIALLY VERTICALLY DISPOSED CLOSE TO THEIR ADJACENT SIDES AND CONFORMING TO THEIR SURFACE SHAPE AND HAVING AT LEAST PARTLY UPWARDLY CONVERGING END EDGES, THE OTHER TWO SLABS BEING AT LEAST PARTLY INCLINED UPWARDLY AND AWAY FROM THEIR ADJACENT SIDES AND RESTING ON SAID END EDGES, THE LOWER EDGES OF SAID INCLINED SLABS CONFORMING TO THE SHAPE OF THE ADJACENT SIDES OF THE INGOT MOLD AND ABUTTING AGAINST SAID SIDES, AND SUPPORT PIECES SECURED TO AND COVERING THE OUTER SURFACES OF SAID INCLINED SLABS AND SERVING TO SUPPORT SAID SLABS AGAINST BREAKAGE AND AGAINST MOVEMENT OUT OF CONTACT WITH SAID END EDGES BY THE PRESSURE OF MOLTEN METAL IN SAID MOLD.