US425846A - Casting ingots - Google Patents

Description

(NOM0de1.) 3Sheets-Sheet 1.

B. AT H A. CASTING INGOTS.

No. 425,846. Patented Apr. 15, 1890,

(No Model.) 7 r 3 Sheets-Sheet 3. B. ATHA.

CASTING INGOTS.

W I F1315 l dy: 6

WITNESSES. INVENTOR 6 %fli ji {B ie 'uminflfim UNITED STATES PATENT OFFICE.

BENJAMIN ATHA, OF NEWARK, NEW JERSEY.

CASTING INGOTS.

SPEQIFICATION forming part of Letters Patent N0. 425,846, dated April 15, 1890. Application filed August 23, 1886. Serial No. 211,682. (No model.)

To all whormit may concern.-

'Be it known that I, BENJAMIN ATHA, a citizen of the United States, residing at Newark, in the county of Essex and State of New J ersey, have invented certain new anduseful.

Improvements in Casting Ingots; and .I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

In casting steel according to the methods heretofore commonly employed a mold of a given size and capacity has been'used, into which one or more ladlesof metal have been poured, depending upon the capacity of the matrix, and the filled mold has been-permitted to stand until the metal has set, when the mold was removed from the chilled mass of metal.

The product of a single filling of the mold is known as 'an ingot, and varies in crosssection according to the diameter of the matrix and in length within certain defined limits from three to five feet, according to whether the ingot is composed of steel treated by the Bessemer, crucible, or open-hearth processes.

It is obvious, therefore, that what has been commercially known as an ingot is a mass of metal conforming to and limited by the size and shape of the matrix in the mold in which the cast is made.

In casting steel in my improved apparatus and by my improved processes the metal is so treated that the product of the cast is not limited to the capacity-i. e., the lengthof the matrix in the mold, exceeding the same many times,-accordin g to the quantity of metal poured.

. To conform to the recognized phraseologyand avoid confusion of terms, the completed product of a casting by my improved process is designated as an ingot, without regard to its length, whetherit is the result of a series of pourings forming an elongated homogeneous mass'of metal containing all of the metal cast or whether the said product is obtained bydividing' said elongated mass of metal into sections of the same.or different lengths, as is more particularly described hereinafter.

The elongated continuous mass of cast metal during the formation thereof, and before it is completed or divided, is designated as the ingot-bar. The invention is therefore designed to form an ingot-bar of steel of indelinite and unlimited length varying in cross section according to the cross-section of the matrix in the mold, the length of the ingotbar being restricted only by the' supply of molten metal and not by the length of the mold. From said continuous ingot-bar may be cut sections of any desired length, according to the purpose to which the metal is to be applied, or the ihgot-barmay be extended in a continuous unbroken ingot integral and unseamed throughout its whole extent.

' One of the most important advantages attained by my improved operation is the effectual prevention of the formation of the piping in-the top of the ingot. When ingots are cast singly int-he ordinary mold and the metal allowed to chill in the mold, the molten metal, when poured, being of sufficient quantity to completely fill the mold, by the contraction which necessarily follows, the -cooling of the metal occupies much less space. This contraction is not uniform in all directions and in all parts of the coolingingot, but takes place first in the ingot at the point of contact of the metal with the inelosing-mold, and results in the formation, primarily, of a surrounding film of chilled metal inelosing the still molten interior of the ingot. -This inelosing film is formed immediately upon the contact of the molten metal with the mold and extends from the bottom of the mold up to the top thereof. Consequently there is no opportunity afforded for any further contrac tion of the inelosing sides ofthe ingot that is appreciable, and what contraction occurs must take place in the interior of the ingot. The result of this contraction and of the gravitation and settling of the cooling metal is the formation of a funnel-shaped opening in the top of theingot constituting the pipe, which oftentimes extends into the ingot one-third of its length and renders such proportion of the ingot useless. tion has been desired by all steel-makers and is essential toproduce a perfect ingot.

In making a continuous ingot-bar by my improved process no opportunity is afforded The obviation of this forma-i for the formation ot' the pipe, as the supply of metal is maintained and the space made I by the contraction of the cooling metal is constantly being tilled by tho inilowing metal, resulting in a. solid homogeneous ingot-bar, which may be subdivided as-desired.

The mechanism illustrated in the drawings is adapted to carry out my. invention, and is described specifically hereinafter.

In the accompanying three sheets of d rawings, in which similar letters of reference indicate like parts, Figure l is a vertical section of one form of the improved mechanism. Fig. 2,is a top view of the mold, the reservoir being removed; Fig. 3 is a section through line .1; Fig. 1; Fig. 4, a side elevation of the intermittent fccd-gearin g. Fig. 5 is a vertical section of" the mold, illustrating the initial step in the process. Fig. 6 is a side elevation of the sliding blocks, and Fig. 7 is a top viewof the same.

As above stated, the primary object of the invention is to form an ingot or ingot-bar of indefinite or unlimited length, which may be done by either continual or successive addilions of molten metal at the top, while the ingot-bar, as it is formed by the cooling of the metal, is drawn from beneath and either cut into short sections or ingots of the usualor any desired length or is drawn through the mold as an extended 'bar of considerable length. 'lo effect this result it is necessary that no obstacle shall interfere with the downward passage of the newly-formed ingotbar after it leaves the mold, particularly in making bars of extendedlngth, the length of the bar being" limited only by the supply of metal at the top, and as such supply may be kept up for an indefinite length of time, so the length of the ingot may be practically unlimited. '-,This indefinite formation and extension of the ingot-bar is accomplished by maintaining the supply and melting temperature of the steel in a suitable vessel or reservoir and conducting the molten metal into a mold,.which is preferably constructed so as to artificially cool the said metal, from which it is drawn by suitable mechanism when sufiiciently set or solidified, and is cut or divided into sections or lengths of the desired length, the flow of the metal from the reservoir into the mold -being simultaneous'with the with drawal of the solidified bar from the mold.

While the employmentof a heated reservoir is considered preferable, as t-herebya constant supply of metal is secured, which flows into .the mold as fast as is permitted by drawing down the growing ingot-bar; still .I

may pour directly into the mold itself upon.

the fluid metal therein should it be considered desirable. The mechanism shown in the drawings for effecting this result consists'of a reservoir A, opening into the interior of the mold B, around which a stream of water is caused to circulate to facilitate the hardening of the metal.

To provide a water-jacket around or in the 'air are conducted to said tubes by mold, various constructions may lie-followed. In Fig. ly the water-channel b is cored out in the solid mold, as shown. In Fig. 5 a waterspace I) is provided between the inner part of the mold b and the outer casing I), or in said water-space aeoil of pipe maybe arranged, as will be understood. The water onters the channel or space at b and flows out at I).

The reservoir is provided with a pouringduct (1, through which the molten metal is pouredor flows into the reservoir, and is intended to be heated or is provided with heating mechanism to maintain the lluidity or molten state of the metal.

The device for heating the metal shown in the drawings consists of an inner tube a, through which hydrogen oifiother gas is adi'nitted into the reservoir, and an outer tube (1 through which atmospheric'air flows, and mixing with the hydrogen ignites at the mouth of said tubes and produces a flame of intense heat, which comes directly in contact with the mass of molten metal and keeps it constantly in a fluid condition. 'lhc gas and suitable pipes, as will be understood.

In lieu of this method of heating the metal, I may surround the reservoir with a coke or other furnace, and by thus heating the reservoir keep the metal at the proper temperature, or by any known or suitable device produce the desired result, it being my intention not to limit the carrying out of this fea- .ture of theinvention to the specific apparatus shown.

Beneath the lower end of the mold is ar- 1 ranged the mechanism for drawing the bar of metal after it has been set sufiiciently downward ,from the mold and delivering it to the dividing or severing mechanism, which is preferably arranged beneath the drawing mechanism. In order that sufficient length of time may he allowed to sever the bar without causing any binding or interference of the parts, the said bar is preferably fed to the severing mechanism intermittently, as will be understood. Said feeding mechanism, as shown in the drawings, consists of the rolls 0 (2, arranged on opposite sides of the ingotbar I, which grip said bar, and when operated,

moving in the direction indicated by the arrows, draw the bar downward as .far as may be desired to'form theingot, the extent of movement of the rolls determining the length of the ingot or portion separated from the continuous bar. The intermittent action of said rolls is so timed as to allow sufficient time' for the metal in the mold to set before the drawing movement of the rolls begins, and also'to permit the severing of the ingot from the bar.

In Fig. 4 is illustrated oneform of mechanism adapted to'produce an intermittent movement of said rolls, consisting of spur g'earwheels'c keyed on the rolls, and a spur gearwheel a having a blank 0 on'the periphery ment and rest of the continuous bar. It-will be understood that this mechanism. for producing. the intermittent movement is but one of many devices adapted to produce the de-' sired operation.

- As above stated, the severing or dividing mechanism is preferably arranged beneath the drawing mechanism, and,as shown in the figures of the drawings, consists of oppositely and reciprocally moving cutters sea, which are removably secured to reciprocally-moving heads 0 e, sliding between ways e and operated by the oppositely-arranged eccentrics e e, arranged on a shaft. A rod e communicates'the movement of the eccentric c to the head eft-he eccentric e turning in a bearing 6 in the head a as shown in Fig. 1-. The movement of the eccentrics is so timed in relation to the intermittent feed that when the feed has stopped and the continuous ingotbar I is at rest, then the cutters move forward, sever the bar atthe desired point, and return to their normal position. Should the movement of the bar not cease at the proper time when the cutters enter the same, the said outters may be bolted to sliding blocks'ff ',which are supported by aweighted lever h or spring g, and if the movement of the said bar continues after the cutters have begun to-work the sliding blocks and said cutters move down ward with the bar, and thus prevent the breaking of the cuttersor the stoppage of the operation. This slidingor yielding action of the cutters is particularly advantageous when the continuous barI is fed to said cutters continuously instead of intermittently, as previously described, the device shown in Fig. 1' being adapted to be used with either an in -termittent or continuous feed.

In lieu of the cross-heads and eccentrics, hydraulic cylinders may be employed, the cutters being secured to the ends of the pistons thereof.

Instead of two cutters, a single cutter and an abutment may be used, the cutter being. operated by'ei-ther of the above-described devices or by any suitable mechanism.

To keep the cutters in a line, abar 1', projecting from-one of the sliding blocks .f and engaging with a groove 7; in the other block 1, as shown in Big. 6, may be used, or the said cutters may be bolted directly to the crossheads e :2 to accomplish the same result.

I may employ a saw instead of the'cutters to=sever-or divide the bar, but consider the cutters preferable, the several ways-referred to, however, indicating a few of many devices that may be used to divide the bar into sections or ingots On Sheet 3-,Fig, 5, is illustrated the first step which is used in casting'wthe metal,which is as follows: A dummy ingotor bar J the upper end of which is preferably dovetailed,

as'shown, is arranged within the mold, the upper dovetailed end extending up to and constituting the bottom of the metal reservoir A, and the lower end of the said dummy ingot extending down between the rolls 0 c.

In the process of casting-the molten metal .is poured into the reservoir, and as the rolls revolv'ethe dummy ingot is drawn through the mold, the molten metal following theq 5 same and filling the mold. During the down ward passage of the dummy ingot there may be one or more cessations of its movement,

during which period of rest the molten metal has time to crystallize'and set, so that when the dummy ingot passes out of the mold down between the cutters and is cut off. the metal has formed a continuous bar within the mold of sufficient solidity to .be drawn down by the rolls a c and fed to the cutters,

as hereinbefore described, and shown in Fig.

1. The dummy ingotacts as a stopper or block to prevent the. escape of the molten metal through the bottom of the mold during the first step in the process-i. e., the'first pouring-and as soon as the said stopper is drawn from the'bottom of the mold or matrix and" the rolls have seizedthe endjof the continuous steel ingot-bar the said stopper isof no further service to continue the process and is entirely removed or severed from the end of the newly-formed ingot-bar.

extend through the entirelength of the ma trix, as shown in Fig. 5, as it may stop at any point therein above the open lower end of the matrix, so-that the metal does not run. through the bottom. of the matrix during the first" pouring; but the said stopper should be so placed as to be seized by the .drawing mech-- anism to enable the same to draw the said stopper and the superincumbentingot-bar down through the mold. As; the capacity of the reservoir is several times'that of the mold and may be enlarged or reduced as desirable,

It'is not considered essential that the stopper should a-censtant supply of metal is provided, which flows into the mold'as the solidified'bar is drawn down from below and cut ofi. Thus .it will be seen that by this apparatus and process a continuous supplyof molten metal is provided, which is constantly being turned into a solidified bar in the water-jacketed mold and the solid bar cut off in suitable length as it escapes or is drawn from the lower end of the mold. The opening orv duct from the metal reservoir-need not necessarily section according to the use to which the prorduct-is to be applied, thetlrawings showing theform commonly used; but the matrix has a. sti-aight axial orcenter line whetherthe crosssection is circular or polygonal inform, and

its-sides are parallel or approximately parallel hum.

e 'being filled with metal either by continuous or successive additions, so that as fast as the bar is drawn down it grows in length by the accretion of metal at the top.

The employment 6f an upright mold pert-- I 5" units the utilization of the gravity of the metalin retaining the fluid metal in the mold whereas any other than a vertical position or approximately vertical position of the mold would necessitate the use of a plunger or pie-. ton to force the metal-into and from the matrix, which, from the nature of steel and the care requisite in handling'it, would be extremely impracticable, although it might be attended with considerable success with tin' z or some of the metals ,Jiaving'a-low fusingpoint.

Q The upright open-top-mol'd permits the i111- limited addition of molten inet'alfto the top of the descending ingot-bar, 1and "may be tinned indefinitely, being limited only by the supply of metal and not by the mechanism. To allow thefluid metal to become sulficiently set or solidified to be handled, it must remain within the mold a certain-length of 5 time, or else;.while,the,lower end of the,ingot-; bar is in the proper condition to bedrawn from the mold, the. overlying metal is in afluid state and would run out from the mold when the solidified lower end had been drawu from the 4o mold. 1 V 1 In forming theingot-bar by a continuous and gradual lowering of the bar the metalis preferably poured into the bottom of the'inold upon the stopper and chills from below; upward. as the 'pouring c'ontinues. This tend-g ency of the metal to run 'out maybe obviated by pouring', as above stated, and draws ing the metal gradually andcontinuously down through a mold of extended length, 'so. that the fluid metal'is'chilled by the time it reachesthe lower open end of the mold. In lieu of a mold of great leng'-th,a-*mold of the usual length may be used, and instead of drawing the metal down or allowing it=fto de- 5 5' scend gradually and continuously the ingotbar is held stationary within the mold. for a given length of. time, then drawn down a short distance, then permitted to stand again, and so on until the process of beating is comploted. By this -intermittent action (moving, downward andstopping alternately and -re peatedly and by secretions of inetal-onithe --top) the formationof the ingot-bar .m'ay'be continued indefinitely; One-advantage of-.theshbrt' mold and the intermittent is that the mechanism ay b ,made much, smaller andmgr 'eom- COD- - lowering of the plunger or stopper, whichis- I pact'and not require the rbom necessary for the extendedmold; but whether. the. long or short mold is employed, an I i ective of 7c the manner of pouring themetal, t e process of the formation or growth of the ingot-bar is the same-viz'., by drawing the same downward through the bottom of the mold and adding molten metal to the top thereof: 7 5

The methodjmost common in casting in gets, as has hereinbefore been mentioned, is

to pour the molten metal into the mold, filling the same. from the bottom upward, the

metalremaining' stationaryin relation to-the. .80 mold until se tw ien. the mold is lifted from the ingot or the ingot from the mold. This metliod'has been worked practically, but is .found to-necessitate the utmost care in pour-z.

ingtl'iemetal into, the mold,it being absolutely essential in orderto form a perfect iiigot that the inflowing stream of metal shall I strikethe, center of the bottomof the mold,

spreading out towardthe sides thereof and the sides of the mold, andalso strikethe cenb. ter of thev gradually-rising surface of the fluid metal untily-the mold is :full. -Any coir tact of the molten metal with the sides of' the mold will. scoi-e'andg'roove the same, rendering the mold unfit for. use in subsequent v castings and alse injuring the surface of the ingot in process of. formation, which must" conform to the shape. and surface of the matrix. Thus it willbe apparent that any incompetency on the part of the workman resultin rom want of skill or care orany ac ciden ,willgrender useless the mold andmany tons of castings. This has been obviated by employing. a movable bottom or plunger moving down through the mold from the top to-the 5 lower-end thereof and by starting thepouring when the bottom or plunger isat the top of the mold, and, drawing the same down asthepou'rs ing continues, thesnrface of the,' metal is mains tained on a level with the top-ofthe-mold, and the sides thereof, are thereby protected from the impingeme'ntof thestream This operationlis very e'fiective in preventing: the Boer ing of the-sidesof the mold, as they are not up exposedto the stream, being always covered withmetal; but, owing .to the peculiar action and distribution of the metal -in.coolingin. this prgcess, it is quite essentialtthatthe plunger bedrawn down insuchaxmanner as .to most effectively meet'the necessary condi tions. of. thecooling metal. The action of the metal in-w'ooling to form the ingot by thisprocess during a-continnous'and gradual the manner heretofore in. loweringtlie plunger',.is ;as follows: Immediately upon the contact of the molten-distal with the top ofv i metal upon the Cblltiwt thereqfwith said sides, the inclosed' interior beiiigstill in a fluid 1-30! of the plunger the metaljflows ofitagainst the. sidesof the mold, also. forming a layerof cdoledj stator As the plunger continues its downward movement, the inclosing-shell of I cool metal adheres to the sides of the mold at the top and the molten metal flows down through the same and spreads out against the sides of the mold below the metal already set and forms a thin film of cooled metal, and so on during the entire downward continuous movement of the plunger, the ingot cooling around the edges thereof and forming a solidified inclosing-shellin contact with the sides of the mold, which grows from the top downward,the interior of the ingot being kept in a fluid state, as it is only therethrough that the infiowing metal can fill up the space made by the lowering of the plunger. llence it will be seen that at somepoint during the entire downward movement of the plunger, just above the top of the plunger or above the top of the layer of cooled metal, which adheres to the top of the plunger and is drawn down with I it, there must be a place extending entirely around the four sides of the matrix where the molten interior of the ingot has last come in contact with the sides of the mold, and which is relatively to the top of the plunger about the same distance therefrom-that is to say,

' owing to the plunger moving continuously and unintermittently downward, the solidification and attachment of the metal upon the top of the plunger are retarded, the quantity on the top of the plunger increasing but very little during the downward movement thereof and after the first impact of the metal upon the plunger. So long as this point of contact of the outwardly-spreading metal is within the mold the formation of the bar goes on; butwhen the top of the plunger reaches the bottom of the mold and passes therethrough the outwardly-spreading metal fromthe interior, not being confined by the sides of the mold, runsout between the top of the said plunger and the bottom of the mold, and the entire molten mass of metal in the interior of the ingot escapes through the opening thus made, leaving a shell of cooled metal adhering to the sides of the matrix and a small quantity of metal adhering to the top ofthe plunger. This must inevitably occur whenever the plunger starts from the top of the mold and is caused to move continuously and gradually down through the mold, because no opportunity is afforded for the metal to anchor itself firmly to the top of the plunger, and the formation of the ingot is not from below upward, but from above downward. Consequently there is not the slightest downward movement of the cooled metal, but downward accrctions of metal only. To avoid the possibility of this occurring, and also to secure the advantages resulting from starting the plunger from the top of the mold-viz., prevention of the scoringof the mold--instead of causing the plunger to move continuously and gradually down through the mold, the said plunger is caused to move intermittingly downward, dropping a given distance, then stopping a sufficient length of time, then dropping still farther and stopping, and continuing in this manner indefinitely, each period of rest permitting the metal to chill and solidify sufficiently to anchor itself to the plunger and the substratum of metal, so that the metal is drawn down with the plunger instead of adhering to the sides of the mold. In this manner by the time any portion of the bar reaches the bottom of the mold it is in the proper condi tion to be drawn therefrom and to be subdivided, if desirable. The growth of the bar from below upward may be attained by arranging the plunger at the bottom of the mold, pouring in a sufiicient quantity of metal upon the top thereof, and allowing the same to stand until chilled, and then draw down the plunger and the superincumbent the metal being added to the top of the downwardly-moving bar being poured so as to chill and adhere thereto. The intermittent method is, however, considered to possess some advantage over the .continuous operation, particularly when the ingot-bar is to be subdivided, as the periods of rest may be utilized in separating the same into the required lengths, thereby simplifying the sev-' ering mechanism in addition to those advantages already mentioned.

The processes herein set forth of casting and forming ingots of steel will form the subject of a separate application, and are de-- invention, I decontracting toward the lower end and extending through the bottom of said mold, and mechanism other than the mold itself constructed and operating to draw the steel 1ngot-bar from the matrix through the bottom of the mold,of mechanism for dividing or separating the ingot-bar into ingots or sections of the desired length, for the purpose set forth. 4

3. In a machine for forming ingots from a continuous steel ingot-bar, the combination of a vertically-arranged ingot-mold provided with an elongated matrix havinga straight axial or center line and sides which are noncontracting toward the lower endand extendt ing entirely throi'lgh said mold, a metal-resermetal continuously instead of intermittingly,

I CC

scribed herein to more fully explain the effect axial or center line and sides which are nonvoir opening into said matrix at the top thereof, means for maintaining the fluidity of the metal in said reservoir, mechanism other than the mold itself constructed and operating to draw the continuous steel ingot-bar through.

the bottom of the matrix, and mechanism for dividing or separating the continuous steel ingot-bar into ingots or sections of the desired length, for the purpose set forth.

4. The combination, with an ingot-mold, of mechanism other than the mold itself constructed and operating to draw the ingot intermittingly from said mold, for the purpose specified.

5. The combination, with an ingot-mold, of means constructed and arranged to draw the ingot intermittingly from the mold and means for separating a portion of lheingot from the ingot, for the purpose set forth.

6. In a machine for forming ingots from a continuous steel ingot-bar, the combination of a vertically-arranged ingot-mold provided with an elongated matrix having a straight -axial or center line and sides which are noncontracting toward the lower end and extending through the bottom thereof, drawing-rolls arranged beneath and adjacent to the lower open end of said matrix and constructed to operate to draw the continuous ingot-bar intermittingly from said lower end of said matrix, and means for producing said intermittent movement of the drawing-rolls, for the purpose set forth.

'1'. In a machine for forming ingots from a continuous steel ingot-bar, the combination of a \"ertieally'-arranged ingot-mold provided with an elongated matrix having a straight axial or center line and sides which are noncontraotin g toward the lower end and extend ing through the bottom thereof, a removable stopper or dummy ingot arranged in said macontracting toward the lower end and extend-.

ing through the bottom thereof, drawing-rolls arranged beneath and adjacent to the lower open end of said matrix and operating intermittingly to draw the continuous ingot-bar from said end of the matrix, means for producing said intermittent movement of the drawing-rolls, reciprocally-moving cutters arranged beneath and adjacent to said rolls,

and means for producing the reciprocating motion of said cutters during the period of rest of said rolls, substantially as aml for the purpose set forth. 7

In testimony that I claim the invention set forth above I have hereunto set my hand this 20th day of August, 1886.

3 L'JAMIN AiI-IA. Witnesses:

FREDK. F. CAMPBELL, Falcon. (1. FRAENTZEL.

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