US1334207A - Pair-heating-furnace hearth - Google Patents

Description

T. V. ALLIS, DECD. H. E. Ams. Aummsmumx. PAIR HEATING FUHNACE HEARTH. APPLICATIUN FILED SEPT. u, 191B.

' 1,334,207 Patented Mar. 16, 1920.

2 SHEETS-SHEET i.

Flai..

A TTORNE Y.

T. V. ALLIS, DEC'D.

H. E. ALLls. ADmmsTRATRlx. PAIR HEATING FUHNACE HEARTH.

APPLICATION FILED SEPT. ll, 1918. 1,334,207. Patented Mar. 16, 1920.

2 SHEETS-SHEET 2.

[N VEN T OR.

A TTORNEY.

UNITED STATES PATENT OFFICE.

THOMAS V. ALLIS, OF PITTSBURGH, PENNSYLVANIA; HANNORA E. ALLIS ADMINISTRA- TRIX 0F THOMAS V. ALLIS, DECEASED.

PAIR-HEATING-FURNACE HEARTH..

Specification of Letters Patent.

Patented Mar. 16, 1920.

\ Application filed September 11, 1918. Serial No. 253,627.

.'o all whomJ t may @Oncem Be it known that THOMAS V. ALLIS, a citizen of the United States of America, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Pair-Heating-Furnace Hearths, of which the following is a specification.

The present invention relates to pairheating-furnacehearths, and is an improve ment whereby the sheet or tinplate bars being heat treated are moved continuously along a hearth composed of a series of transverse metal sections or hearth skids having alined grooves, from the charging `end to the discharging end ot' such furnaces.

Means is provided whereby the length of the transverse sections composing the hearth is standardized or held to a uniform dimension, and the overall length of the furnace hearth as a whole increased 0r reduced b the use of raised bosses of varying thic (ness on the ends of the individual transversescctions as Willbe more fully eX- plained hereinafter in this specification.

Other features and advantages of the resent invention are similar to those of nited States Patent, Number 1,034,858, pair heatingfurnacel hearths, dated lAugust 6, 1912, and reissued under date of December le, 1915, as Reissue Patent Number 14,032, invented by Thomas V. Allis. Reference is made to said reissue atent for a fuller understanding'of the ac vantages of furnace hearths having inclined grooves for supporting the sheet or tinplate bars at an angle with the horizontal on their lower longitudinal edges'and one side; and also as to the continuous handling of such bars in the hearth grooves with their abutting ends crossed so that power applied to move one piece, moves its contacting neighbor in the saine sustained line and direction along the grooves of the furnace hearth.

Means are also provided by which a series of grooved transverse metal sections or skids which make up the hearth of the furnace as a whole, are held so that the longitudinal grooves remain in alinement, and the said sections also prevented from advancing longitudinally along the furnace bed, as will `more fully appear as the description proceeds herein.

1n the accompanying drawings forming part of this specification I have shown one conrplete example of the physical embodiment of my invention constructed according to the best mode I have so far devised for the practical .application of the principles of my invention.

Figure 1 of the drawings is a transverse vertical section on line 1-1 of Fig. 2 of a pair-heatingfurnace, showing my invention in operative posit-ion therein.

Fig. 2 is a horizontal section on line -2-2 of Fig. 1.

Fig. 3 is a longitudinal section on line 33 of Fig. 2. r

Fig. 1 is a plan view of one of the standardized transverse metal hearth sections shown in Fig. 2.

Fig. 5 is an end view of Fig. G, taken from the left of saine.

Fig. 6 is a side elevational view of two transverse hearth sections, or skids, in oper ative position with respect to each other and taken from the right as seen in Fig. 5.

Fig. 7 is a longitudinal section taken on line 7-7 of Fig. 5.

The numeral 1 indicates a pair-heating furnacel provided with a. fire box 2, preferably located on one side of the furnace as shown, a bridge wall 3, mechanical stoker 4, and a heating chamber 5. Leading from the heating chamber 5 are the downtake flues 6,'which convey the products of combustion to the stack (not shown). The heating chamber 5 is provided with the usual'charging and dischargin openings 7 and 8 respectively, and with lifting doors 9 and I1() therefor, for the admission and withdrawal of the sheet or tinplate bars being heat-treated in the furnace.

Within the heating chamber 5 is the furnace bed or bottom 11, on which rests the transverse hearth sections 12, 18, etc., prefrably formed of cast steel, comprising the whole furnace hearth 14.

Each transverse section, or hearth skid, 12, is cast with a plurality o-f parallel grooves 15. 15, in which the bars 22, 23 are placed so that their abutting ends cross each other as shown in Figs. 1 and 2, in which it is seen the pile of bars marked 22 and 23 alternately cross each other as they lie in the said grooves. It is seen from the Fig. 2 that whenthe end bars 22 adjacent to the charging end 7 are advanced by use of a power pusher or other means, that a full longitudinal series of bars 22, 23, etc., simultane- Cir - a transverse row ously advance toward the discharging end 3; and further the full collection of bars upon the furnace hearth 14 can likewise be silnultaneously by advancing all the bars 22 which lie in of grooves, adjacent to the charging end 7 of the furnace. When the bars 23 nearest the discharge end 8, which lie in the transverse row of grooves of the hearth skids 13', are withdrawn as being sufficiently heated, a new and cold transverse series of bars can be entered in the grooves 15 from the'charging end 7 of the furnace. And so on indefinitely the bars are continuously charged, pushed forward, and withdrawn from the furnace as they become suiiiciently heated, for the subsequent steps in the manufacture of the bars into sheets. The bases of the grooves 15 are cut away at 16, and the corners at 17, 18 arel rounded so that the bars do not moet with any obstruction in the bases of the grooves 15 as-they are pushed along said grooves.

It is further seen that in the manipulation or turning over of the plates from a position such as indicated by 22 in Fig. 1, to a position 23, that the saine is greatly facilitated by the wide, cut-out and rounded grooves 16 shown in the drawing, and particularly well illustrated in the Figs. 4 and 5. Stiti'ening ribs 19, 19 are provided, preferably at theedges 20, 20 of the section 12 of a form as indicated at 44, of the.Fig. 7, and under the basesA of the grooyes 15 there are convex bosses 21, formed as shown to transfer the weight of the bars 22, 23, etc., to the furnace bed 11. Similarly at the sides 24, 24 of each transverse metal section 12. the ribs 19 are. extended downwardly at 25, 25, slightly below the bottom of the bosses 21, as seen in Fig. 1. The ribs 19 arealso cut away at 26 to admit the crosssection of the centering bar 27.' The purpose of the centering bar 27, which is preferably of cast metal, is to maintain the grooves 15, of the several hearth skids 12, in longitudinal,alinement for the ready passage of the sheet and tin plate bars through them from the charging end 7 to the discharging end 8 of the furnace.. The centering bars 27 are preferably formed of a doable T cross-section, provided with strengthening webs 28, 28, and are grouted rigidly into the furnace bed 11. The said bars 27 are of such length as will allow the skids 12 to slide along them when expansion or contraction takes place due to temperature changes. The hearth skids are molded with concavities 29 under each apex 30, and between the ribs 19, 19 to save weight.

Each groove 15 of the skids 12, it will be seen is beveled on the charging side 31, in two directions horizontally at 32, 32 and vertically at 33, forming an outwardly and downwardly flaring mouth in each of the advanced over the skids l2 grooves 15 for tlu` more facile entrance of the sheet or tinplate bars 22, 23 into said grooves.

On each of the edges 20, 20 of each transverse section or hearth skid 12, 13, etc., a plurality of raised, and preferably semispherical bosses 34, 35 are formed for a purpose as will be explained below. On the skids 13 I have shown a pair of downwardly projecting` lugs 36|formed preferably as extensions to the ribs 19, and these lugs 3G only occur on the discharge cnd 37 of the section 13 nearest the discharge opening 8. The said lugs 36 are let into" the brickwork of the furnace hed 11. so that when the bars 22, 23 which are piled in the sections 12` l2. etc., are advanced from the charging end 7 toward the discharge end 8 ot' the furnace by means of a power pusher, or otherwise, the forward thrust of the various sections 12, 12. etc., which bear against the skid 13, is transmit-ted to the furnace bed 11 by means of the lugs 3G.

One of the most important features of in v invention is its adaptability for use in Inaking up hearths 14 of varying lengths, by using transverse sections 12 of one uniform length in conjunction with separating bosses 34, 35 of varying thicknesses as indicated by the dotted boss 38 and boss 35 of Fig. (l. This feature is best explained by an example such as usually obtains in practice in the art involved. llVe will assume a hearth 14, of approximately'twelve feet in length is desired from point 39 to 40 Fig. 2, and that the standard length of hearth skids 12. in use is fifteen inches. Nine standard skids having bosses 34, 35 nineteen thirty-seconds of an inch in thickness can be used, making an overall length of twelve feet and onchalf inch. In. a similar fashion standard skids of fifteen inch length, and having bosses seventeen thirty-seconds of an inch in thickness, will make up a furnace hearth having an overall dimension of nine feet, three and one-half inches. These examples show the adaptability of these skids to producing hearths of varying overall dimensions, which is a very important feature in practice. The saving in metal by having,r the interstices 41 between the sectons 12, 12. etc., instead of a continuous metal hearth from points 39 to 40 is also seen to be a matter of importance.

As stated in the above Reissue Patent Number 14,032 by piling the bars in grooves having an inclination to the horizontal. transverse hearth space is economized; and by crossing the abutting ends of adjacent bars, mechanical advantage is gained in the facility with which the bars are advanced longitudinally along the grooves of the hearth. These features and advantages apply to the present invention, and it is noted that when the side walls of the grooves are lll Ell

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and the same hearth grecs with the horizontal (whichis consid ered the preferable `angle of inclination) that the side edges 42 of the hars 22 and 23 form a substantially uninterrupted straight line, without protruding edges, and as a result any uneven heating, and unnecessary oxidation of the edges ot' the hars is thereby prevented.

In operating my improved hearth, the bars are charged thereon as before explained through the charging end 'Y of the heating chamber singly or 1n collection, standing either at the same or reversed inclination in the grooves 15. When a full transverse row of grooves 15 are filled they are (preferably) simultaneously advanced. along the grooves by a power pusher or other means. second transverse row is then charged, the abutting ends of each of the latter being in crossed` relation with respect to the adjacent ends of the bars lirst charged. The whole hearth in this way is completely filled with hars, and as those on the hearth skids i3 are withdrawn through the discharge doors l0, cold hars are introduced through the charging door 9, and inY this way the heat-treatment of the lhars is equal and continuous. All the hars in this 'Way -pass through the seme zone of heat, for a like time period, and consequently very unit'ormly heated hars continuo produced, which it is well understood, .is a do sideratum much desired. Iin this lt is understood that each of the grooves lli is so proportioned as to width and that the distance from the suritace 43 against which. the lower edges oi the sheet hars 22 bear, to the apen 30, is always greater than half the width of the hars 22 heing treated so as to maintain the latter in stable eoyiilihriuino ln practice the grooves are made oi such dimensions that the'largest site hars can he safely supported. then he used for smaller sized hars.

From the ahove it is l have provided. a very useful and convenient form of hearth. adapted to he used to maire up hearths of varying sites hy lusing transverse sections or skids of substantially uniform length, and possessing the other ieatures and advantages ahove set forth.

Whatl claim is :mf

l. A transverse hearth shid provided with va plurality oit' grooves adapted to support a number ont sheet hars in an inclined. posiu tion therein, stidening ribs under the grooves, and spacmg bosses on said rihs projecting heyond the end laces et the slrids.

2. A transverse hearth skid having grooves for supporting plurality ot `sheet hars in an inclined position therein, stienribs under the grooves, outstanding said.

depth spacing bosses on the end faces of the skid,

and a number of downwardly projectin extensions on one of the stili'ening ribs a ore? 3. A .transverse hearth skid provided `with grooves for supporting a number of sheet bars 1n an inclinedv position therein, cutaway and rounded hase portions formed '1n the grooves, 'and outwardly and down- Wardly flaring mouths connecting with the same, the said base portions and Haring mouths of said grooves being designed to vfacilitate the ready entrance, free passage and manipulation of sheet hars in and along the hearth skid grooves. i

4:. A transverse hearth. section provided with grooves having cut away rounded bases and beveled mouths, ladapted to support a plurality of sheet vhars in an inclined position therein, still'ening ribs beneath the grooves, and outstanding spacing bosses on the ends of the said section.

5. A grooved furnace hearth composed of a plurality of ansverse sections having a common'length dimension, adapted to support a number oi sheet hars in an inclined position, and. spacin means tor holding the said sections a fixe distance apart,

(i, .A furnace hearth composed of a niunhier of grooved sections adapted to he arranged transversely of the ituruuce, for holding a longitudinal series of hars in alined and inclined positions, a phiralityIA oi centering hars mounted in the furnace bed slidahly engaging the'ends of adjacent sections, and a nuxnher ci downwardly projecting lugs formed on the sections and engaging the furnace hed tofprevent longitudinal movement of said hearth sections along the furnace hed.

l. A furnucehearth composed ola hor of transvorsesections provided with a' the sections to torni hearths of variahle overall lengths. l

9. A. hirnuce hearth composed et a U plurality of grooved transve sections 'adapted to support. a longitudiintl series of sheet hars in an inclined position, a nurnber oi centering hars mounted in the turnace hed slidahly engaging' the ends olf adjacent sections, iid means for varying the distance heti` n ,the sections to 'form hearths of ver overall lengths.

10'. A furnacefhearth.composed-ol a plurality of hearth skids cut away base portions, and outwardly Haring mouths, adapted to'suppor't a longitudinal series of sheet barsininclined positions, sald sectlons being arranged transverse of the direction of movement of the said bars through the furnace, in combination with means on the hearth skid nearest the discharge end of the furnace, engaging. the bed of the lfurnace to prevent forward movement .of the skids when the sheet bars are advanced along the grooves ofthe same.

having grooves with.

11. A transverse hearth skid having grooves for supporting'a plurality of sheet 15 THOMAS v. ALLIs.

Witnesses:

T ILLIAM A. HIRTLE, EMMA LEA MONTGOMERY.

whereof aiiix my signature 20 v1n the presence of two Wltnesses.

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