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Nov. 23, 1937. c. H. ALDRICH 2,099,670 STOOL TO BE USED IN THE CASTING OF METAL Filed (Jet. 22, 1935 15% FW km‘ INVENTO‘R 2,099,670 Patented Nov. 23, 1937 UNITED STATES‘ ‘PATENT . OFFICE 2,099,670 STOOL TO BE USED IN THE CASTING OF METAL Charles H. Aldrich, Elizabeth, N. J., assignor to The American Metal Company; Limited, New York, N. Y., a corporation of New York Application October 22, 1935, Serial No. 46,096 .8 Claims. (Cl. 22—139) to overcome these di?iculties and thereby to lengthen the useful life of the stool. This gen erally is done by subdividing the stool into a This invention relates to stools, or other sup porting structures, for open-bottomed ingot molds or the like, and more speci?cally to a composite stool which is particularly resistant to the cor '5 rosive and other destroying effects of molten plurality of component parts which are yieldingly pressed together so that they may expand and contract independently one of another whereby > In the manufacture of ingots, molten metal is opposed expansional stresses are avoided; and by utilizing different materials in different parts of poured into a suitable mold and allowed to con geal therein, whereupon the mold is removed and , the stool to counteract different destroying forces. 10 again used. In carrying out the casting process The latter feature is accomplished by making that it has been found that the poured metal tends to portion of the stool against which the molten metal. 1 metal ?rst strikes, termed the “area of direct-im pingement” from a material which will resist to a maximum degree the cutting action of the stream of molten metal and which is of such 16 character as not to become welded to the ingot; I and by making the remaining portion of the stool, cut away parts of the mold, and that the tre mendous amount of heat which is released by the molten ingot frequently results in a cracking of l5 the mold surfaces. . Usually it is the bottom of the mold which gives way ?rst. Consequently, in the past, it has been the practice to form the bot tom' of the mold separately from the side por termed “the area of non-impingemen ” from a tions thereof, whereby the bottom, or stool as it ' material which will distribute the heat evenly 3 O .as it was poured into the mold. accompanying drawing, in. which Figure 1 is a plan view of a stool which incor no further use. < ‘ Later it was proposed to build the stool from a solid block of copper which, having a much greater coefficient of heat conductivity, would tend to 4 o. distribute the heat of the casting morerapidly and more evenly. This expedient was relatively satisfactory, and such stools had a far greater life than the prior cast iron one.v However, in time the stream of molten metal would begin to cut and erode the surface, and further, cracks and ?ssures eventually appeared. _ 9. In both of the foregoing typesof stool consid erable trouble was caused by the tendency of the poured metal to weld itself to the stool. This, as can readily be understood, resulted in a very considerable loss of time in separating the ingot from the stool, and further, it tended to con taminate the metal of the ingot. 85 porates the principles of my invention; Fig. 2 is a cross-sectional view taken along the line 2-—2 of Fig. ,1; , The principal object of the present invention is V ‘ . Fig. 3 is a fragmentary cross-sectional view of a stool embodying my invention and showing a modi?ed form thereof; Now,‘ uneven heating results in uneven expansion; and where one part expands more than another then the ‘metal will buckle or crack. Accordingly, after a relatively short period of time, these cast iron 3 stools became‘ so covered with cracks as to be of 20 Other objects and various features of the in vention willbe more apparent from the following description to be read in connection withv the heat conductivity, and consequently the heat of the poured metal was unevenly and rather slowly ‘distributed therethrough, and dissipated there .from. In other words, the heat tended to con centrate at that point, or in that area, against which~the stream of molten metal ?rst impinged 2 5 and rapidly therethroughout. is called, may be replaced when it becomes worn. In the past several di?’erent types of stools have been proposed. One of the earliest of these was made of a solid block of cast iron; This metal, as is well known, has a relatively low coe?icient of 2 o. Fig. 4 is a similar view of another modi?ca tion of the invention; Fig. 5 is a fragmentary plan view of a stool in which either of the modi?cations of Fig. 3 ‘or 4 35 > may be included. ' Y ~ vOne embodiment of the invention, as'shown in Fig. 1, comprises a plurality of relatively narrow bars II and I2 which are disposed in side by side relation and mounted upon a suitable bed 40 l3. As can be seen, the bars are of a length somewhat less than the width of the bed. Con sequently, any expansion lengthwise of the bar will not be opposed by the sides of the bed; that I. is, the bars are free to move in that direction. 45 Further, the bars are yieldingly pressed together in such manner that any expansion crosswise thereof may be absorbed by the yielding means. Accordingly, each bar may expand in this ~di rection independently of every other bar. Thus, 50 as will be apparent from the foregoing, the com ponent parts of the stool are free to adjust them selves in any direction whereby opposed expan sional and contractional forces are completely avoided. - ' 55 2 2,099,670 The. yielding means above referred to may take any desired form, as for example, it may comprise springs M which are held in compres sion between a suitable header l5 and the spring seats I6. The tension of the springs may be adjusted by means of bolts I‘! which are threaded into thelend section I 8 of the bed with one end abutting against the spring seats I6 whereby any rotation of the bolts will increase or de 10 crease the spring tension dependent upon the direction of rotation. - When molten metal is poured into a mold’ mounted upon such a stool it will usually strike the latter at one point or within a relatively small 15 area and then ?ow over the remaining portions thereof. After the stool has been used a number of times it will be found that this area of direct impingement has become corroded to a very marked extent; and that the ingot tends to weld 20 itself to this area. In other words, the stream of molten metal tends to cut away the part of the stool against which it strikes, and then tov weld itself thereto. ' The extent of these effects ‘will be found to differ with the character of metal 25 which is being cast. Thus, in general, high car bon steel and certain alloys have a greater tend ency to cut the stool and to become welded there to than do low carbon steels and other alloys. Accordingly, _the bars II which constitute the 30 area of direct inpingement are preferably made of amaterial which will oppose these tendencies to a maximum degree. In practice, it has been found that cast iron and certain alloys will re sist these destructive effects when certain types 35 of metal are being cast, while in other cases such ' refractory materials as carbon, graphite, carbo-_ rundum, ?re clay, magnesite, chromite and the like, must be used. Thus, the material which is to constitute the area .of direct impingement 40 will be selected in accordance with the character of the metal which is to be cast. The remaining bars I2 constituting the area of non-impinge ment are preferably made from copper, or other material having a comparatively high coefficient of heat conductivity. ' " Inindividual cases it will be found that the area of direct impingement may constitute a greater, or lesser, proportion of the total area ‘ of the stool; and a greater, or lesser, proportion 50 of the total depth thereof; and the arrangement" of this area may be varied in several ways. In Fig. 3, for example, the direct impingement bars Ila are only approximately half as deep as the adjoining bars l2, and they are underlaid by an equal number of bars [211‘ which preferably are formed of the same metal as the bars l2. Fur ther, these bars may extend the total width of the stool, as is illustrated in Fig. 1, or they may be fore-shortened, as is shown in Fig. 5. In the 60 latter case the area of direct impingement will be substantially surrounded by the bars consti tuting the area of non-impingement; that is, it will be adjoined on both sides by bars l2, on the ends by bars I25, and it will be underlaid by 5.5 65 bars I211; ‘ 1 ' ' - Another variation is shown in Fig. 4, in which the area of direct impingement may constitute a solid block of the desired material; and this block may extend the full depth of the stool, or 70 it may be in a lesser proportion. Further, it may extend the full width of the stool or it may be foreshortened in a manner similar to that illus trated in Fig. 5. Considering the advantages of the stool as a 75 whole it will be seen that the composite character permits a selection of those materials which will best counteract the destructive effects of the molten metal. Thus, the‘ bars II which are in tended to resist cutting and welding may be chosen in accordance with the character of the metal which is to be cast; and the bars l2 may be made from a metal which will evenly and rapidly distribute the heat of casting. The lami nated character of the stool not only avoids cracking, as hereinbefore described, but it per 10 mits an easy and rapid change of the character of the area of direct impingement. Each of the foregoing features tends to lengthen - the effective life of the stool. Accordingly, in practice, it will be found that this composite type 15 stool has a considerably longer normal life than anything heretofore proposed. Further, such a stool may be very readily and inexpensively re paired. Thus, the laminated construction makes replacement of worn bars a relatively simple 20 matter; and the inexpensive character of the area of direct impingement, wherein most wear occurs, permits replacement of this area at a very small cost. Since certain changes may be made in the em 25 bodiment of the invention without in any way departing from the true scope thereof, it is in tended that the foregoing shall be construed in a descriptive rather than in a limiting sense. 30 What I claim is: 1. A composite‘ stool for an open bottomed ingot mold having an area of direct impingement formed from a material which is highly resistant to the corrosive action of a stream of poured molten metal, and an area of non-impingement 35 formed from metal having a high coefficient of heat transfer whereby it may rapidly and evenly distribute heatthroughout the entire stool, both the area of direct impingement and the area of non-impingement being formed from bars which are disposed in side by side relation, and the stool being further characterized in that the area of direct impingement is underlaid by a portion of the area of non-impingement. 2. A composite stool for an open bottomed in 45 got mold having an area of direct impingement formed from a plurality of relatively narrow bars of cast iron which is adapted to resist the corro sive action of a stream of poured molten metal, and an area of non-impingement adjoining the 50' area of direct impingement, the area of non impingement comprising a plurality of relatively narrow copper bars disposed in side by side rela tion and adapted to distribute the heat of the cast ingot rapidly and evenly throughout the entire 55 stool. _- - - 3. A composite stool for an open bottomed ingot mold comprising a plurality ‘of relatively narrow bars disposed in side by side relation with the side surface of one bar in contact with the side surface 80 of the adjacent bar so that their tops form sub stantially a continuous surface upon which an ingot may be cast, certain of the bars constituting that portion of the stool against which a stream of poured metal would be most likely to strike 65 being formed from a material which is adapted to resist the corrosive action of such a stream, the remaining bars being .formed of copper whereby they are adapted to distribute the heat of the cast metal rapidly and evenly throughout the stool. 70 4. A stool according to claim 3 in which the bars constituting that portion of the stool against which a stream of molten metal would be most likely to strike are made of a refractory material. 5. A stool according to claim 3 in which the bars $099,670 constituting that portion of the stool against which a stream of molten metal would be most likely to strike are made of cast iron. 6. A composite stool for an open-bottomed ingot mold having an area of direct impingement com prising a plurality of bars of metal highly resist ant to the corrosive action of a stream of poured molten metal, and an area of non-impingement comprising a plurality of bars of metal having a high heat transfer coei?cient whereby it may rap idly and evenly distribute heat throughout the entire stool, the stool being further characterized in that all of the bars are disposed in side by side relation, and that the bars comprising the area of direct impingement are underlaid and adjoined on two sides by the bars constituting the area of non-impingement. 7. A composite stool for an open-bottomed ingot mold having an area of direct impingement com 20 prising a plurality of bars of metal highly resist— ant to the corrosive action of a stream of poured molten metal, and an area of non-impingement comprising a plurality of bars of metal having a high heat transfer coefficient whereby it may 3 rapidly and evenly distribute heat throughout the entire stool, the stool being further characterized in that all of the bars are disposed in side by side relation, and that the bars comprising the area of direct impingement are underlaid and surrounded by the bars constituting the area of non-impinge ment. 8. A composite stool for an open-bottomed ingot mold, comprising a plurality of relatively narrow bars of substantially identical size and shape dis 10 posed in side by side relation with the side surface of one bar in contact with the side surface of an adjacent one, so that their tops form substantially a continuous surface upon which an ingot may be cast, the middle bars constituting that surface against which a stream of poured molten metal will ?rst impinge being formed from cast iron so as to resist the corrosive action of such molten stream, and the remaining bars constituting the end surfaces being formed of copper so as to dis tribute the heat of ‘casting rapidly and evenly throughout the stool, the ‘cast iron bars being of substantially the same depth as the copper ones. CHARLES H. ALDRICH.