US2914825A

US2914825A - Slotted hot top

Info

Publication number: US2914825A
Application number: US636146A
Authority: US
Inventors: Marburg Edgar
Original assignee: United States Steel Corp
Current assignee: United States Steel Corp
Priority date: 1957-01-24
Filing date: 1957-01-24
Publication date: 1959-12-01
Anticipated expiration: 1976-12-01

Description

E. MARBURG SLOTTED HOT TOP Dec. 1, 1959 3 Sheets-Sheet 1 Filed Jan. 24, 1957 IN VE/V TOR E 0 6A MARBURG',

his Attorney.

Dec. 1, 1959 E. MARBURG SLOTTED HOT TOP 3 Sheets-Sheet 5 Filed Jan. 24, 1957 3/ E 064/? AMA RBURG; B ,4 a y his Attorney.

left of Fi'gure 3;

. Figure is a top plan view 2,914, 25 -S TED ot Top e lt 'farburg, l ittsb urgh, Pa., assignor to United States Steel Corporation, a corporation of New Jersey Applicationlanuary 24, 1957, Serial No. 636,146

' i 12 Claims. c1. 22-147 fThisfinvention relates to a slotted hot top and more particularly to aghottop; for use in casting hot steel ingots. It has been proposed to use slots in hot tops such as suggested by Turner Patents Nos. 2,049,981 and 2,049,-

982 and- Estep PatentNo. 2,159,374. However, the slots shownstherein extend completely through the hot top so .,thatgi.f the hotmetal flows into the slots it is exposed directly to the air. This will cause the metal to chill qrapidly and providemeans for conducting heat directly gramme top of theingot. If the metal does not rise in the slotsthe jslotsact as chimneys to convey heat directly from the top of the' ingot. In either case the extraction aofheat from the top of the ingot promotes undesirable trans-solidification across the ingottop.

referring to the following specification and attached drawings, in'which:

Figure 1 is a plan view. of a sectional hot top assembled on'an ingotfmold;

i United States Patent 0 the slab 4 for a purpose which will appear later. The tops of the end of the slabs 4 are preferably cut away at 18 so that they are wider at the bottom than at the top. A generally vertical groove 20 is provided in the inner face of slab 4 a short distance from each end thereof. The bottom of thegroove 20 tapers downwardly and inwardly at 22 for a purpose which will appear later. The inner side wall 24 of each groove20 is vertical for the most of its length, but slopes outwardly in a downward Figure 2is 'anenlarged plan view showing the joint bet'ween anend and side slab;

' Figure-3 is anelevation of the side slab looking toward its inner face; a. a t t v 1 "Figure 4 isanend view of the slab looking toward the v of the=slab of FigureS;

Figure 6 is a view, similar to Figure 3, showing the end slab'.

' Figure 7 is an end view of the slab looking toward the left of Figure, 6;,

Figure Sis a top plan view of the slab of Figure 6;

Figure 9 is a view in elevation showing the assembled slabs on a-mold section and looking inwardly from the outer side of an end slab;

Figure 10 is a view of a side slab, similar to Figure 3,

showing a second modification of my invention;

Figure 11 is an end view of the slab looking toward the leftof Figure 10;

Figure 12 is a top plan view of the slab of Figure 10;

Figure l3is a view, similar to Figure 6, showing a modified end slab which is usedwith the slab of Figures 10 to 12; u

Figure 14 Ban end view of the slab looking toward the leftof Figure 13; and

Figure 15 is a top plan view of the slab of Figure 13.

Referring more particularly to the drawings, reference numeral 2 indicates the top of a rectangular big-end-up mold. The hot top consists of two refractory side slabs 4 and two refractory end slabs 6. The side slab 4 has a sub- '14. A plurality of holes 16 are provided in the wall of direction at its lower end 25 so that the groove is narrow-v er at the bottom than at the top. A generally vertical slot 26 is provided in the upper outer side of slab 4 adjacent each of its ends.

End slab 6 has a generally vertical inner face 28 while its outer face has a depressed portion 38. The contour of the lower portion of the outer face matches the mold wall. The bottom of the inner face 28 is rounded at 31. Each end ofthe slab 6 has a generally vertical tongue 32 which has tapered sides 34. The width of the upper parallel portion of tongue 32 is less than the width of the upper parallel portion of the groove 20. The lower portion of the tongue 32 has a tapered portion 35 which is of the same slope but slightly closer to its basethan tapered portion 22 of slab 4. The inner face of the tongue 32 is tapered at its lower end to provide a wedge surface 32 of the same slope but slightly nearer itsbase than the tapered portion 25 of slab 4. Portion 36 of the end face is normal to the face 28. Portion 38 of the end face slopes inwardly toward the other end face of slab 6. The height of the tongue 32 adjacent portion 36 is slightly greater than the depth of groove 20 and the height of the opposite side of the tongue 32 is less than the depth of the groove 20. A generally vertical slot 40 similar to slot 26 is provided on the upper outer face of slab Gadjacent each end.

The parts so described except for minor differences are the same as those shown in my copending application, Serial No. 581,181, filed April 27, 1956. My invention in the present application relates to the addition of a pair of narrow vertical slots 42 in the side slabs 4 and similar slots 44in the 'end slabs 6. The width of the slots is preferably not more than 4 inch. The slots are open at their lower end and'extend upwardly about two thirds the height of the hot top or to any height less than that of the hot metal poured into the hot top. I P

To assemble the hot top on the mold 2, a A :inch round steel pin 46 is placed in corresponding holes 16 (depending on the height of ingot desired) and the side slabs 4 are placed on opposite sides of the mold 2 with the pins 46 resting on top of the mold as best shown in Figure 9. The end slabs 6 are then inserted between the side slabs 4 with the tongues 32 in the grooves 20. Because groove 20 is wider than tongue 32 in its parallel upper portion, the tongues 32 will pass readily into the grooves 20. When the slab 6 reaches the point where

bevelled faces

22 and 35 are in engagement the outer sides of the side slabs 4 are forced towards the mold wall. At the same depth the lower bevels 25 and 32' contact each other, and end slabs 6 are forced outwardly towards the mold wall. With clearances allowed, the slight difference in height of

bevelled faces

22 and 35 and corresponding bevels 25 and 32' results in the tops being aligned when a tight fit is secured. When the top of end piece 6 is level with the top of side piece 4, the side face 34 of tongue 32 contacts the outer face 24' of groove 20; hence the end slab 6 cannot drop below the level of the side slab 4. After the four slabs are assembled, a generally U-shaped spring clip 48 is forced downwardly across each joint between the slabs with its legs in the

slots

26 and 40.

The above manner of assembly is essentially that shown in my copending patent application. However, as steel is Patented Dec. 1, 1959' 3 poured intothe mold it canno-trise intothe

narrow slots

42 and 44 because of the narrow width of these slots and because the slots are not vented. However, air will be entrapped therein an'd wilhbe heated to a-yery high temperature,=thusserving as a-neffective'barrierto transverse heat flow from the sinkhead throughthe hot top wall.

' i Figures to showa second modification 0f my inventionin which the construction and assembly is the same as that of the first embodiment except for'the provision of the slots.- Therefore, like reference numerals *are u'sedto indicate corresponding parts. In this embodimentwideslots. 50 are 'providedin thetside slabs 4 and "similar "slots 52 are provided inthe-end slabs 6. The -width of the slots is'preferably at least inch. The slots are open-at their'lower ends and extendupwardly two-thirds the height of the hot top or to anyheightless -=than that-of the metal poured intosthe'hot top. Slotted -vents '54 extend from-the top of .the slots 50 to the inner surface of the slab 4. Similar'slotted vents 56 extend from the slots 52 to the inner surface of theslab 6. When steel is teemed into the mold it will-rise in the slots50 1 and then inwardly through the slotted ,vents '54 to form steel'fins which are-connected directly to the sinkhead. This preventsthe finsfrom fiaringoutwardly;during rolling. Since the metal fins in the

slots

50 and 52 are completely enclosed within the hot top wall the entrapped layer of hot steel will greatly retard heat flow through uthe walls of the hot-top and much less heatwill belost --than in the conventional hot top. It will be understood thatthis arrangement of slots may be incorporated ina "one-piece =hot top as-well as in the sectional hot' top described.

While several embodiments of myinvention have -been shown and described it will be apparent thatother adaptais relatively wide and there is an opening extending from p the top of the slot to the inner side of said-body-member. '4. A hot top according to claim 1 in which the slot extends upwardly approximately two-thirds the height of the body member.

5.. A sectional-hot top for insertion withinthewalls of a mold comprising a first pair of refractory slabs supported on said mold in spaced relationship, a second pair of refractory slabs located between and in abutting relationship with said first pair of slabs, each end of both of the slabs of one of said pair having a generally vertical groove in its abutting faceyand a generally vertical portion adjacent each-end ofbothvofi-the slabs of the other of said pair projecting into the corresponding grooves of the'other slabs, each ofsaidislabs havingaslot extending upwardly-from the bottom of--the-1ab for-afiistanoe less. than the full-heightthereof. i

6. A sectional hot top according to claim 5 in which the slot is relatively narrow and its top closed.

7. A sectional hot top according to claim 5 in which the slot is relatively wide and there is an opening extending from the top of the slot to the inner side of said slab.

8. A sectional hot top according 'to =claim S in which the slot extends upwardly approximately two thirds 1 the height of the slab.

9, A sectional hot top 4 for insertion within J the=walls of a' mold comprising a first pair of refractory slabs supported on said mold in-spaced relationship with-each other, a'second pair-of-refractory slabs located between and in abutting relationship with-saidfirst pair of slabs, and means on said slabs for wedging them againstithe 'mol'd wall,-each' of said slabs having aslot *extending .upwardly from within'the mold and from the bottomof the slabfor'a distance less than the fullheight thereof; 1

10. A- sectional'hot top according-to claim 9 in which the slot is relatively narrowand itstopclo'sed.

11. A sectional hot top according to clairn-9which the slot isrelatively wide and there is an opening extending from the top of the slot to the inner side of said slab.

12. A sectional hot top according to claim 9 in "which the slot'extends upwardly approximatelytwo-thirds the height of the slab.

References Cited in' the file of this patent UNITED STATES PATENTS