US2369299A - Apparatus for working metals - Google Patents

Description

Feb. 13; 1945. J. KAFOWI 2,369,299

I APPARATUS FOR WORKINGMETALS Filed May 16, 1942 2 Shets-Sheet 1 l v r -INVENTOR.

41 JAN KAFOW/ A ORNE Patented Feb. 13,1945

APPARATUS FOR WORKING METALS Jan KafowL Long Island City, N. Y. Application May 16, 1942, Serial No. 443,224

Claims.

. This invention relates to an apparatus for working metals and more particularly virgin metal, scrap metal and other metal stock which 'is melted and cast into a larger ingot and thereafter pressed or extruded in the heat into smaller ingots having a predetermined size and weight for subsequent drop forging or hot pressing into a desired final shape.

In particular, this application forms a continuation in part of my co-pending patent application Ser. No. 374,922, filed January 1'1, 1941, now

Patent No. 2,314,403, issued March 23, 1943. As I have discovered and disclosed in said co-pending application, it is possible to subdivide a larger ingot into a number, two as a minimum, of smaller ingots of a shape and size predetermined by the shape of cavities of a mold or die into which that larger ingot is pressed at proper heat. Any metallic ingot can be so subdivided, whether ferrous or non-ferrous, and particularly consisting, e. g., of aluminum, copper, nickel, zinc,.lead,-magnesium and their alloys, especially brass and bronze. The optimum temperatures of pressing such larger ingots into smaller ones in a single step appear to be about40% to 20% below the melting temperature of the metal or alloy, and if brass or bronze are concerned well above about 650 C. v

A power driven-press in which the larger ingot is so subdivided may be of the friction; hydraulic or steam type, and the pressure may be appliedsubstantially instantaneously or during a short period of time while the ingot is hot and not yet solidified. In the former case a kind of drop deformation, i. e., without fissures and folds and without causing undesirable strains in the smaller ingots.

In my above mentioned co-pending application, I sug ested the use of a mold or die comlength of the cavities.

of the smaller lngots to be produced, in particular of cylindrical configuration. Usually the cavities are equal in size and shape, and longer than the individual smaller ingots. The crosssections of the cavities may be of any desired configuration, such as circular, square, rectangular, etc., and are usually the same over the entire Taking a given cross section of those cavities and thereby area in a plane vertical to the direction of pressing, the individual size of the smaller ingots depends upon the len th of the cavities in the direction of pressing.

I discovered that the same die can be used for the production of a great variety of sizes of smaller ingots. Taking a metallic larger ingotof given ,size and exerting upon it considerable pressure while it is at proper heat its material will be distributed substantially equally in the cavities and fill them closely whether there is a bottom provided for the cavities or not. Thus with a given cross section and length of the cavities, a number of smaller ingots can be produced therein the horizontal cross section of which corresponds to that of the cavities and the length of which is solely determined by the amount of material pressed into each of them. If the cavities are almost filled by the material pressed into them, the larger ingot or blank from which they are obtained has its maximum size. If the larger ingot is -of smaller size, the individual cavities will be filled by the pressed-in ingots to a smaller extent, i.- e., theindividual smaller ingots will be all of the same cross section again but shorter.

If it is desired to produce smaller ingots of different cross sections, particular dies are to be prepared each time having cavities of such a desired cross section. This results in a stock of a great many dies each comprised of high quality steel and provided with machined-in cavities and hardened thereafter.

It is an object of the invention to reduce the 1 number of dies to be prepared and held in stock prising an open receptacle or recess for receiving the larger ingot and thereafter the ram or mold cover for pressing theingot into the mold cavities communicating with that receptacle. The

mold or die consisted .of any suitable material,

P b y high q y steel, which was hardened,

for producing smaller ingots of desired horizontal cross Section, i. e., in a plane substantially ver.--

tical to the direction of pressing.

It is another object orthe invention to reduce the 'amount of valuable high quality steel or similar die material for producing smaller individual ingots of diflerent horizontal cross sections as defined above.

It is still a further object of the inventionto reduce the work and cost of preparing-dies for producing .smaller individual ingots or different horizontal cross sections as defined above.

These and other objects of the invention will be more clearly understood when the specification proceeds with reference to the drawings in which Fig. 1 shows a cross section with some parts in elevation through a die according to the invention, Fig. 2 a perspective view and'cioss section through a larger ingot particularly usable for the invention, Fig. 3 an elevation of the smaller ingots as obtained after molding a larger ingot and connected by a sort of flash, Fig. 4 a cross section with parts in elevation of a modificationof a die accordin to the invention, and- Fig. 5 a cross sectional view taken along line 5 5 in Fig. 4.

In the illustrations of the invention shown in the drawings by way of exemplification, only the essential parts of a molding or extrusion apparatus are shown. As stated above and in my co-pending patent application, the die can be used in any kind of molding, forging or extrusion press.

Referring to Fig. 1, a die holder or receptacle I is provided with a recess 30 in which a die proper ll is fitted. The die is provided with a recess |'2 open on top for receiving a larger ingot, and a number, two as a minimum, of holes or cavities M which taper downwardly at an incline of, e. g., 1:10. Recess l2 opens into another larger recess on top of the die which has a ringshaped bottom 36 upon which, if desired, any number of thin, ring-shaped shims-3'! can be po sitioned.

Sleeves or hollow inserts l are tightly fitted into the holes l4. Each sleeve is tapered onthe outside at the same incline as the holes I4, thereby securing a tight all-over fit. The inside cross section of sleeves I5 is of any desired configuration as stated above, and circular in this exemplification of the invention. Thus, each sleeve I5 is cylindrical inside.

Die may be made of any desired strong material, such as iron or steel, and only sleeves l4 can be used for receiving sleeves l5 of the same outer shape but different inside configurations and sizes corresponding to those of the smaller ingots to be molded therein; thus, only the thickness of the walls of the sleeves or inserts l5 will vary.. While, however, according to my previous suggestion a whole die II was to be prepared of high quality material, the cavities to be shaped therein to exact size and the die thereafter to be hardened, now, according to my present invention, die II can be used for a great many sizes and shapes of smaller ingots to be produced and only sets of sleeves. l5 are to be prepared for each required size and shape of the smaller ingots. Thus, a great amount of valuable high quality material for the die is saved. If a given set of sleeves or inserts I5 is worn out during operation, they are to be replaced by new ones which can be used with the same die whereby another substantial saving on material and work in hardening is obtained. It is also easier to machine the relative small inserts; worn out inserts can be bored out to slightly larger diameter and used for producing correspending ingots 4|. i Die holder I0 is provided with a smaller recess 32 below the large one 30 and a hollow member 34 is inserted therein. Member 34 is provided with a number of bores IS in alignment with holes l4 but of a diameter "equalling or smaller than the smallest diameter of the holes in the sleeves l5.

In the hollow space 35 of member 34, a plunger I or plate 22 is slidably arranged and connected with rod 26.

Holes (not shown) may be provided in plate 22 permitting communication between space 35 and the outside air.

Ejecting rods 20 are slidably arranged in each hole l9 and seated upon or connected with plate In assembling the die, member 34 is first inserted into recess 32 and seated on its shoulder 33 formed by the ,bottom portion23 of the die holder l0. tightly and accurately fitted therein, isfitted into recess and seated upon shoulder 3| of that recess. Subsequently, rods 20 are slipped through the holes I9 and plunger 22 inserted into the hollow cylindrical space 35.

In operation, a blank 38, Fig. 2, of cylindrical shape and properly heated is inserted into recess l2 and almost fills it, and thereupon a into recess l2.

plunger or ram 39 having a reduced projection 40 is pressed upon the blank in the manner described in my above identified co-pending application.

Preferably an instantaneous blow is thus exerted upon the blank or-larger ingot. There may as possible and before it cools'and solidifies, into the cavities formed by the holes of inserts I5.

Fig. 1 shows ram 39 in its lowermost position after having exerted an instantaneous blow or sufllciently high pressure upon the blank or larger ingot so as to press the latter in a single step into the holes of inserts I5 and to form therein the desired smaller ingots 4| which are connected by a sort of flash 42.

The horizontal cross sections of the smaller ingots 4| correspond to those 'of the holes in the inserts l5, and they are of equal length within very small tolerances. The thickness of flash 42 is determined by the size of the larger ingot and the extent to which ram portion 40 is pressed The sizes of the larger ingots can be kept equal within small tolerances in their production; hence, the end position of ram portion 40 determines the size of the smaller ingots 4| as well as-of fiash 42. those sizes as exactly as possible either ram 39, 40'can be machined so accurately that ram 33 strikes shoulder 36 just when individual ingots 4| and a flash 42 of predetermined sizes are produced. If flashes 42 of difierent thicknesses are desired, different rams would become necessary. In order to avoid it at least to a certain extent, thin shims 31 are placed upon shoulder 36 in such a number that the same ram will come to rest at different distances from shoulder 36 wherefrom different desired thicknesses oi flash result.

After the larger ingot'has just beentransformed into smallexvingots 4| connected by a flash 42, as shown in Fig. 3, plunger or plate 22 is moved upwardly by. rod 26, while ram 33, 40 is lifted simultaneously, and the ejector rods l9 eventually eject the ingots 4|. By breaking up flash 42, the individual ingots 4| are separately Thereafter 'die' If) with sleeves |5- In order to adjust cavities.

' those larger ingots.

It will be appreciated that the hot initial larger grain structure is applied to those ingots. The relatively large mass of the mold or die'secures a rate of cooling which prevents any quenching action; if the latter be desired, the die H or die holder II) should be provided with channels through which a cooling medium is circulated.

As I'disclosed in my above mentioned co-pend- It should be understood, however, that a die as shown in Fig. 4 can be ,used the same way as a die shown in Fig. l, i.'- e., that the individual smaller ingots do not bebome seated /on top of heads r2l but end in some distance therefrom, as

- is assumed and shown in Fig. l.

ing application, I discovered in casting metallic bodies that holes, deep depressions or fissures can be successfully avoided if certain dimensions are imparted to the body. I found optimum results if the height a (or largest vertical dimension), Fig. 2, is about half the diameter 17 (or largest horizontal dimension) of the ingot or blank 38.

It is understood that by using a larger or initial ingot of those approximate proportions, a highly.

dense initial ingot is pressed into smaller ingots which retain that density or, if possible. are even more densified by the pressure exerted for deexemplification of the invention accord ng to Fig.

1, holes [4 in die H are tapered upwardly, and so are sleeves or inserts IS on their outside. The latter are tightly fitted into the holes I4 and held in this position by plate member ll.

Ejector rods 20 are prov ded with enlarged heads 2|, which are slidably arranged in the cylindrical holes or cavities I6 of sleeves I5 and thereby apt to form It will be appreciated that upon placing a larger hot ingot into recess l2 uponits shoulder l3, and

exerting pressure upon that ingot, it will be squeezed into and fill the holes" l6 and. if the size -of the larger ingot be large enough, the smaller ingots will be seated upon and their lower ends shaped by the heads" 2| then acting as bottoms' of cavities Hi. It will further be appreciated that by adjusting the position of plate or plunger 22 with-- in space 35, also the position of the heads or bottoms 2| in the cylindrical cavities Hi can be adjusted and thereby the size of the smaller ingots determined. In such'case. ram 39 should not be stopped by-shoulder 36 or shims 31. in order to se- It is sometimes difficult to align the reciprocating ram 39, 40 exactly with die ll so that ram portion) in its lowermost position is exactly centered within recess l2 or with respect to the usually symmetrically arranged cavities in inserts I5. In order to facilitate such alignment or cen-v tering, die holder l0, Figs. 4 and 5, is provided with a somewhat eccentric flange 144 havinga conical. outer surface 45. A ring 2& is provided with an inner conical surface of the same incline as surface 45, and can be fastened by' a number of screws 28 to a support 415. In order to bring die H and its recess I2, Fig. 4, in exact alignment with ram 39, 40, the axis and path of which is determined once and for all by the structure of the press, screws 29 are somewhat loosened and die holder in turned within ring 28 until the formers axis is in exact alignment with that of the ram;

thereafter screws 29 are tightened. It is also possible to turn. ring 28 relative to die l0 and to fasten it in any one of the six positions determined by the screws 29. It will be understood that by enlarging the number of screws and/or by providing alarger number of threaded holes in support 45 to receive those screws, the number of positions of ring 28 relative to die I 0 and its flange 44 can be increased to any desired extent.

' Of course, both methods described above for a bottom within and of thosecure that the cavities are filled completely by the larger initial blanks result .in a flash of larger horizontal dimension. 1

- claims. 65

centering die l0 relative to the ram can be combined, i. e., die H) turned within ring 28, and the latter turned relative to support 46.

Holes '25 serve to'permit escape of air during] if it is desired to' establish an open communica tion between the space outside. a

While I have described above specific advantages of my present improvement, it should be understood that all the other advantages ascribed to my basic invention in my above identified copending application apply the same way to the invention presently described. It'should be further understood that my invention is not limited to the, specific features herein set forth, but to be derived in its broadest aspects from the appended below plate 22 and the 'What I claim is:

1. For combination with a power press, such as an extrusion press, a die having opposite fronts, a

first and larger cavity in said die opening in one of said fronts for receiving an ingot or blank and a pressing ram, a plurality of second cavities in said die of considerably smaller cross sections than that of said first cavity. said second cavities open- ,ing at one end into said first cavity and at the other'end into the second of said fronts, said second cavities tapering toward one of their ends, and individual hollow inserts exchangeably fitted into said second cavities and opening flush with the latter into said first cavity, each such insert tapered at its outside the same way asthecavity into which it is fitted and shaped at it'shollow inside conforming to the individual configuration ,-to be applied to metallic material to be pressed therein.

2. For combination witha p wer press. such as an extrusion press, a die of iron or steel having oppos'ite fronts, a first and larger cavity in said die opening in one of said fronts for receiving an ingot or blank and a pressing ram, a plurality of second cavities in said die of considerably smaller cross sections than that of said first cavity, said second cavities opening at one end into said first cavity and at the other end into the second of said fronts, said second cavities tapering toward one of their ends, and individual hollow inserts of hardened high quality steel exchangeably fitted into said second cavities and opening flush with them into said first cavity, each said insert tapered 'atits outside the same way as the cavity into which it is fitted and shaped at its hollow inside fronts, a first and larger cavity in said die opening in one of said fronts for receiving an ingot or blank and a pressing ram, a plurality of second cavities in said die of considerably smaller cross sections than that of said first cavity, said second cavities opening at one end into said first cavity and at the other end into the second of said fronts,

said second cavities tapering toward one of their ends, hollow inserts exchangeably fitted into said second cavities, each such insert tapered at its outside the same way as the cavity into which it i i fitted and shaped at its hollow inside conforming to the shape to be applied to metallic material to be pressed in said die, a die holder provided with a recess into which said die is t d, m unting means exemplified by a ring for mounting said die holder on a support, and projecting means exemplified by a flange associated with said die holder, said mounting and projecting means adjustably engaging one another along a conical surface arranged slightly eccentrically to the centre axis of and tapering toward said die.

4. In combination with a power press, such as an extrusion press, for subdividing a large ingot into a plurality of smaller ones, a die having opposite fronts, a first and larger cavity in said die ingot or blank and a pressing ram provided with a laterally projecting shoulder to enter into said third cavity, a. plurality of second cavities in said die of considerably smaller cross sections than that of said first cavity, said second cavities opening at one end into said first cavity and at the other end into the second of said fronts, said second cavities tapering toward one of their ends, hollow inserts exchangeably fitted into said second cavities, each such insert tapered at its outside the same way as the cavity into which it is fitted and shaped at its hollow inside conforming to the shape to be applied to metallic material to be pressed in said die, and removable means as exemplified by shims arranged within said third cavity for determining the lowermost position of said shoulder and thereby said ram for pressing an ingot placed in said first cavity into the hollow spaces of said inserts. 1

5. For combination with a power press, such as an extrusion press, a die having opposite fronts, a first and larger cavity in said die opening into one of said fronts for receiving a metallic ingot or blank and a pressing ram, a plurality of second cavities in said die of considerably smaller crosssectional areas than that of said first cavity, said second cavities opening at one end into said first cavity and at the other end into the second of said fronts, said second cavities tapering towards one of their ends, individual hollow inserts exchangeably fitted into said second cavities and opening flush with the latter, each said insert tapered at its outside in the same way as the cavity into' which it is fitted and shaped at its hollow inside conforming to the individual configuration to be applied to metallic material to be pressed therein,

and a die holder in which said die is seated, said die holder including a member against which said die and inserts therein abut at the second of said fronts.

JAN KAFOWI.

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