US922587A - Ingot-casting machine. - Google Patents

Description

L. E. HOWARD.

INGOT CASTING MAGHINE.

AYPLIOATION FILED MAR. 9, 190a.

Patented May 25, 1909.

- 3 sums-sum 1 L. E. HOWARD. INGOT CASTING MACHINE. APPLIUATION FILED MAR. 9, 190a.

Patented May 25, 1909.

3 SHEETSSHEET 2.

L. E. HOWARD. INGOT GASTING MACHINE. APPLIOATION FILED MAR. 9, 1908.

922,587. Patented May 25,1909.

3 SHEETS-SHEET 3.

b 1 l a! I w 6 $1. w

' UNITED STATES PATENT OFFICE.

LESLIE E. HOWARD, OF LA. GRANGE, ILLINOIS, ASSIGNOR TO SIMONDS MANUFACTURING COMPANY, OF FITCHBIJ'RG, MASSACHUSETTS, CORPORATION OF MASSACHUSETTS. a

' INGOT-CASTING Specification of Letters Patent.

Patented May 25, 1909.

ab'pueafinu filed March 9, 1908. Serial no 419,943.

It all whom may contem:

Be it known that I, L'nsLIE E. HOWARD, a

citizen ofthe United States, residing at La, Grange, 1n the county. of Oookand State of One object of this invention is to provide an improved a paratus for preventing the formation of b ow-holes and cavities .iningots due to the separating out. of gases from the steel comprising the ingot during the cooling of the same, and the'formationof the defect known as piping due to the shrinkage of the metal after the outer sides and bottom ofthe ingot have set and hardened and while the center is still molten, which condition allows the molten metal from the upper portion of the ingot to feed down and. partly replace that drawn toward the sides of the lower portion of the ingot owing to shrinkage and cooling This piping or shrinkage cavity is usually confined to the upper portion of the ingot, but may, and often does, extend nearly or, quite the'rethrough.

A further object of the invontion'is to refine the steel by breaking up the coarse crystallization caused by the slow undisturbedcooling of the ingot' as it is usually allowed to proceed, which latter weakens the envelop of metalloids surrounding the crystals of steel, causing a partial loss of'cohesion between the crystals. I have found that once this straining and weakening of the steel has taken place, no subsequent heat or mechanical treatment, such as rolling or forging, will fully restore the steel to the strength of like steel in which the formation of coarse crystals and shrinkage has been prevented.-

My invention consists. of an improved I ingot-casting machine in which the ingots are cast, and which is adapted to compress the ingots during the period in which they are passing from the molten to the solid state, such compressing operation commencing immediately after the ingots are poured, and being relatively verygently at first but increasing in force as the ingots become denser as cooling proceeds, the pressure being graduated so as to prevent molten steel flowing from the upper to the lower portion of the ingot until the ingot has set or be- .passed.

come solid throughout its mass; and after this has occurred the pressure is further increased, producing an effect on the steel similar tohydraulic forging, and the pressure is continuedv until the steel has cooled to a thermal point somewhat below its point of recalescence, and the crystals formed throughout the mass of the steel will not undergo any further change by subsequent cooling. To accomplish these results it is essential that the pressure be applied continuously' from the commencement of cooling until the point of recalescence is reached or While the invention is adapted to the pr'oduction of ingots of all sizes and shapes, it is especially well adapted to ingots of small sizes, such as are commonly used in the manufacture of tool steel products.

In the accompanying drawings I have illustrated one practical form in which the principle of the invention may be embodied, in 'wh1ch- Figure 1 is a top plan view of my improved machine. Fig. 2 is a 'side elevation'of the same. Fig. 3 is a cross-section on the line 33 of Fig. 1. Fig. 4' is a cross-section on the line .4-4 of Fig. 1.

- Referring to the drawings, 5 indicates the.

main frame of the machine of a rectangular and generally box-like form with its top and bottom open, which frame may be cast n one piece, but preferably, and as herein shown, is composed of side and end members secured together, as by through-bolts 6, and which contains and supports the casting molds and the principal parts of theoperatin mechanism thereof.

.o the inside of one end (hereinafter referred to as the rear end) of the frame 5 are suitably secured compressing cylinders 7, herein shown as two in number, superimposed, with t i longitudinal axes horizontal and para el to each other, and slidably fitted with rams or plungers'8 and provided with pipe connections 9 by which they are J connected to a source of fluid pressure (not frame when partially removed by pins 16 cross-head, and the heads 21 of said bolts being confined-in inner enlargements 22 of or rigidwith the crosshead.

. in a movable member 25. This latter is p votally mounted at 26 on an arm 27 in turn pivoted at 28 1n and between depending .to the ingots consist of thi and the inner ends of the plunger 8 is fitted a through piston-rod 31 and a link or pitman in number disposed side by side, said molds being formed-in part by a heavy verticai two mol ward projection 12 forming thetwo inner side walls of the molds, and securely fastened to the frame 5 by clamps 13, which clamps are suitably formed on their inner ends to engage recesses drilled in the sides "of the block 12 near its top, and are. held in place by bolts 14. Y 15 designates verticaily and laterally shiftable outer side plates of the molds constituting their outer side walls, which are loosely supported against dropping through the block oraplate 12 forming the backs of the i s, said block havinga central in-" integral therewith or secured therein near their upper ends and normally resting at their outer ends on the top edge of the sides of the main frame. The remaining side members of the molds which are the active agents in transmitting the pressure ap lied c upright p ates or bars 17 between the outer sides of which heavy cross-head 18, the wei ht of which is carried by a bottom late 19 ig. 3) secured as-by bolts 20 to thehottom edges of the two sides of the main frame 5. The forward face of the cross-head 18 abuts directly against the outer surfaces or walls of the mold'members 17; and the latter are-secured to the cross-head for pur oses of effecting the retraction of the mo (1 members by means of bolts 21 tapped into or formed integral with .themold members v1,7, said bolts passing through'vertical slots 22 in the face of the saidslots by means of removable keys 23 (Fig. 3). 'lhe'mold members 17 might, of course, be made integral with the cross-head, but are preferably made detachable, as shown, for the sake of renewal or repairs, when necessary, without involving the expense of a new 'cross-head. Furthermore, the connection described better facilitates an equalizing of the pressure throughout the full length of the ingot than where the com-. pressing mold-members are made integral The bottoms of the twin mold-chambers are closed by a bottom plate 24 that lies loosel rackets 29 of the sides of the main frame. The arm 27 is caused to swing ap )roximatcly 90 degrees on the shaft 28 by the action of fluid pressure in a motor cylinder 30 beneath and secured to the main frame acting 32 pivoted at 33 to the arm'27.

l teferring now to the means for applying an elastlc and yielding pressure upon the the outer sides of the mold-members 15, withvahich are included means for effecting the retraction of the mold-members 17 after the compression has been completed, 34 designates upper and lower pairs of rectangular bit-1?; slidably fitted'in zrooves 35 (Fig. 3) formed on the inside surfaces of the two side members of frame 5; and. attached to the ends of these bars at the mold end of the machine are spring wed e members 36. The inne1 or o erative inc ined faces of these wedge'mer'n ers bear and operate against correspondingly inclined projections or shoes 15 formed on the outer sides of the moldmembers 15. These bars, with their attached 'wedges, are given" a longitudinal movement b the action of fluid pressure on a difierential tached to the outer rear end of the main frame 5, acting through connections conpiston .37 in acylinder 38, at-

sisting of apiston-rod 39, pin '40, cross-bar inner ends of the wedges 36 will engage lugs and thus retract the cross-head, the moldmembers 17, and the rams or plungers 8.

The fluid pressure cylinders 30 and 38 are provided with suitable Valve-controlled fluid pressure supply-pipes (not shown) adapted to admit the fluid pressure alternately to opposite sides of the pistons of said cylinders at the proper intervals in the operation of the machine, such controlling devices being old and well known and constitutingl no part of the present invention. The cy 'nder 38 is preferably provided with a differential piston as shown, permitting a greater pressure to be obtained foreflecting the retractingtravel of the wedges, which is desirable in the event that the wedges are inclined to stick.

In the operation of the machine, the compressing mold-members 17 are adjusted to osition shown in Fig. 1. The bottom of the mold is then closed b causing the bottomplate 24 to form a c osed joint at the bottom end of the longitudinal moldmembers through the agency of motorcylinder 30; This causes a slight lifting of the lateral mold-members 15, insuring a tight.

joint between the'bottom plate and all four sides of the mold. The lateral mold-members 15 are then crowded inwardly of the mold through the agency of the motor cylinder 38, wedges .36, and connections therebetween, insuring tight vertical joints between said lateral mold-members and the members 12and 17. Molten metal is then poured into the mold-chambers by hand or y a suitable pouring ladle .until the molds their top. Fluid pressure is then applied to l the cylinders 7 through the supplyipes 9.,

causing a longitudinal movement of t 1e plungers, cross-head, and compressing moldmembers 17 toward the mold end of the machine, and lessening the cross-sectional area and volume of the mold-chambers. The operator watches the exposed top ends of the ingots under treatment and, through the valve 11 or other pressure-regulating means,

graduates the fluid pressure acting on the plungers so as to efiect'a sufficient contrac- I tion of the cross-section of the ingots during their change from the molten to the solid state as to. cause the gradually decreasing portion of. molten metal to remain always approximately even and of uniform height with the solidifying sides of the ingots. As soon as the top ends of the ingots appear solid, the

pressure is increased somewhat more rapidly,

' bination with a vertically disposed mold hav causing a slight forging or kneading action to take place throughout the mass of the ingots, and this pressure is maintained until the metal has attained .a stable state of or stallization. The desired compression of t e ingots having been thus effected, the supply and exhaust of fluid pressure to the motor cylinders and 38 are reversed, thus dropping the bottom plate 24,- retracting the wedges 36, and releasing the pressure of the lateral mold-members 15, and an instant later retracting the cross-head 18 and the compressive mold-members '17; This entirely frees the compressed ingots and leaves them free to drop through and out of the bottoms of the mold-chambers into the space beneath the machine or into any-suitable receptacles therefor. The molds are then again adjusted and prepared...for subsequent operations, as above described. In practice several of these machines maybe provided, placed side by side alongside of a melting fu-rnace or between two furnaces, or otherwise, as may be most convenient in each instance, with their mold ends all in the same-relative positions, and the pouring of the molten metal into the molds is best accomplished by means of a pouring ladle in a manner at present well understood and extensively practiced in connection with the production of crucible steel.

I am aware that the practice of applying pressure both laterally andendwise to a steel ingot during its cooling from a molten to a solid state with the object of eliminating bubbles and piping and securing a more. solid and uniform texture to the entire ingot is broadly old; but the apparatus hereinabove described and forming'the subjectmatter of the present invention is designed and believed to effect these desirable results with a high degree of efliciency and with infor. a

vin'the mold, substantiallyas compression. Whether the. machine emany delay resulting from the treatment of the 5 other ingot'or ingots simultaneously under going compression; and by making at least two sides ofthe mold retractible, the cooled. and compressed ingot can be readily 'd-ischarged without sticking-and delaying the re-use of the mold. Furthermore, the dropbottom feature enables the com ressed ingets to be quickly disposed of-t irough the action of gravity alone without requiring the use ofhoisting apparatus to get the ingots out of the molds. "These and other advantages of the a paratus will be readily apparout to those 5 illed in the art, and therefore, without limiting myself to the precise con-- struction shown and described,

I claim:

1. In an ingot-casting machine, the com ing a removable bottom late adapted to close its lower end, and a aterally movable side member, of means for applying pressure to the latter whereby to effect compression of the ingot in the mold, substantially as de scribed.

2. In an ingot-casting machine, a mold substantially rectangular in cross-section and having two of its adjacent sides movable,

in combination with-means for laterally moving one of said movable sides to effect a tight joint, and means for applying pressure to the other of said movable sides whereby to compress the ingot in the mold, substantially as described.

3. In an ingot-casting machine, a vertically disposed mold substantially rectangular in cross-sectionand' having a removable bottom closure and furtherhaving two of its adjacent sides movable, in combination with means for laterally moving one of said movable sides to efie'ct a tight joint, and means lying pressure to the other of said mova e sides whereby to compress the ingot escribed.

4. In an ingot-casting machine, a vertically disposed mold substantially rectangular in cross-section and having a removabtfl'! bottom closure adapted to permit the discharge of the ingot through the bottom of I the mold, and further having two of its adjacent sides movable, in combination with means for elastically holding one of said movable sides in operative position during the molding of the ingot, and means for a plying pressure to the other of said movable sides whereby to'compress the ingot in the mold, substantially as described.

5. In an ingot-casting machine, the combination with. a frame, of a vertically dis posed mold mounted in one end of saidfralne and having a laterally 'movable inner side member, a plunger cylinder and plunger mounted in the other end of said frame, a cross-head slidably' mounted in said frame between and in contact with the outer end of said plunger and the outer face of said movable mold-member, connections between said cross head and movable mold 7 member adapted to effect the retraction of the latter, and means forretractingsaid cross-head after compression of the ingot has been effected, substantially as described."

6. In an ingot-casting machine, the combination with a frame, of a vertically dis-' posed mold mounted in one end of said frame and having adjacent laterally movable side members, a lunger cylinder and plunger mounted in t e other end of said frame, a cross-head slidably mounted in said frame between and in contact with the outerend of said plunger and the outer face of one of said movable mold-members and loosely connected to the latter, means for holding said-other laterally movable mold-memberinoperative position during the molding of the ingot, and

means for simultaneously releasing thelatter and retracting said cross-head after compression of the ingot has been eflected,' substantially as described.

7. In an ingot-casting machine, the com-v bination with a frame, of a vertically disposed mold mounted in one end of said frame and having adjacent laterally movable side members, a plunger cylinder and plunger mounted in the other end of said frame, a

ross-head slidably mounted in said frame etween and in contact with the outer'end of cent sides laterally movable, in combination with means for supporting said mold in an n right position, and a removable. bottom 0 osure permitting the discharge of the ingot by gravity through the lower end of the mold, substantially as described.

9. An ingot-mold of substantially rectangulai 'cross-section having two of its adja-' cent sides laterally movable, in combination with means for supporting said mold in an, upright position, and a hinged bottom'fplate permitting the discharge of the ingot by gravity through the lower end of the mold, substantially as described.

v LESLIE E. HOWARD.

'- Witnessesa SAMUEL N. PoNn, ".Fnnnnmcx O. Goonwnv.

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