US2184048A - Ram for extrusion presses - Google Patents

Description

` w, 1939. c. w. KRAusE l v2l84,048

RAM FOR ExTRusroN PRESSES.

I Filed Jan. 7, 1939 Patented Dec. l 9, l 93@ E? Sinti@ RAM FOR EXTRUSON PRESSES Charles Walter Krause, Detroit, Mich., assigner to The Forging and Casting Corporation, Fern-- dale, Mich., a corporation of Michigan Application January 7, 1939, Serial No. 249,679

f 12 Claims. (Cl. 207-19) This invention relates to rams for extrusion a suitable embodiment of the present invention presses and other like uses, the principal object and in which like numerals refer to like parts being the provision of a ram of this type that is throughout the several diierent views,

` highly efiicient in operation, capable of with- Fig. 1 is a more or less `diagrammatic partially standing the severe usage to which such rams broken, partially sectioned View of an extrusion are subjected in service without rapid deteriora press provided with an extrusion ram constructed tion, and that is relatively economical to manuin accordance with the present invention;

facture and to service. Fig. 2 is an enlarged sectional view taken in Objects of the invention include the provision a plane passing diametrically through the exof an extrusion ram so constructed and arranged trusion ram shown in Fig. 1; 10

as to be capable of withstanding high compres- Fig. 3 is an end elevational view of the ram sion columnar stresses and bending produced shown in Fig. 2 taken on the line 3-3 of Fig. 2; thereby and hardened and tempered in an imand,

proved manner; the provision of a ram of the Fig. 4 is a transverse sectional View taken on type described which is hardened and tempered the line l-4 of Fig. 2. 15 and includes a main body portion of hollow con- As is well understood by those skilled in the formation enabling a more uniform hardness to art, rams used in the extrusion of metals and be obtained in the same than is possible in conparticularly those employed in the extrusion of ventional constructions; the provision of a ram ferrous metals, copper, brass, aluminum and the 2O of the type described so constructed and arlike are required to withstand tremendous pres- 20 ranged as to minimize its tendency to warp in sures and relatively high temperatures. Addihardening and bend in service yet capable of tionally the operative end of the ram must be of withstanding the high pressures and temperasufficient hardness to properly withstand the tures required service without mushing of the scoring or abrading action arising due to its conoperative end thereof; the provision of a ram of tact with the cylinder liner during an extrusion 25 the type described including a hollow main body operation. Conventional practice is to make such portion so constructed and arranged as to min rams solid and of a suitable steel, and subject imize danger of warpage thereof in hardening the ram to a suitable hardening and drawing and to provide a maximum resistance to bending operation which results in the ram having a in service, together with a nose portion so con- Brinell hardness of appoximately 450 which it will f" structed and arranged as to be capable of withmaintain under the temperatures met with in standing the high temperatures and high presservice. Such hardness is usually sulcient to sures niet with in service without mushing, toprevent the nose or operative end of the ram from gether with means releasably securing the nose unduly mushing under the high temperatures and piece of the main body portion together; the propressures met with in service, as well as to suit- 35 vision of a ram of the type described in which the ably withstand the abrading action of the ram main body portion and the nose piece are formed on the liner. However, because of the fact that of materials having materially different characthese rams are made solid, and because of their teristics; the provision of a ram of the type derelatively large diameter, the hardening operascribed formed for special co-action between the tion sets up internal stresses within them due 40 nose piece and the main body portion; the proto the difference in hardness between the inside vision of a ram of the type described having a and the outside of the ram. It has been found novel means for securing the nose piece and the that because of these internal stresses which act main body portion together; and the provision to preload the material of the ram, slight misi of a ram of the type described that is simple in alignments in the press in which the ram works 45 construction, efoient in operation and economicauses the ram to bend. I have found that by cal to produce. reducing the surface hardness of the solid ram The above being among the objects of the to 350 Brinell, the internal hardening stresses present invention, the same consists in certain are reduced to such an extent as to overcome the .1U novel features of construction and combinations bending above referred to, but when this is done of parts -to be hereinafter described with referthe nose portion of the ram does not exhibit the ence to the accompanying drawing, and then good wearing properties thereof desired in claimed, having the above and other objects in service.

View. Nose pieces of special alloy steel have been In the accompanying drawing which illustrates electrically welded to the ends of solid rams as 55 above described so as to provide them with an end portion capable of withstanding the high temperatures met with in service Without ai" fecting the extreme hardness which it is possible to obtain in such special alloys. The addition oi such special alloy nose pieces has been accornplished particularly in connection with the sal-- vaging of conventional types of rams in which the ends or noses have become so worn, upset or otherwise aiected in service as to render them no longer suitable for use. In salvaging rams in this manner, in order to prevent reduction in the diameter of the ram, it is iirst necessary to upset the nose end of the ram to be salvaged so that enough stock is available for subsequent machining. After upsetting, the nose end of the ram is trimmed down to permit the introduction of the special analysis nose piece and this nose piece is then electrically welded to the shank. Following the welding it is necessary to re-heat treat the shank and to heat treat the nose. The nose being of a special heat resisting material and the shank having essentially high physical properties after heat treatment, the heat treatment employed for the welded composite ran-is must necessarily be a compromise between that most desirable for the shank and that most desirable for the nose, with the result that neither the shank nor the nose are provided with the heat treat most .desirable for the physical prop erties desired in them.

It has been suggested heretofore to employ a separate nose piece of a special alloy steel as above referred to and to secure it upon the end of a solid ram by means of a stud or the like. While such construction permits the nose piece to be replaced upon becoming worn, and permits the nose piece on the main body portion of the shank to be hardened independently of one another and thus avoid the disadvantages of the welded construction above referred to, the connection between the nose piece and the main body portion of the ram is not satisfactory for the reason that, due to the repeated f cooling and heating of the end of the ram the type of connection employed permitted looseness to develop between the nose piece and the main body portion and, additionally, the main body portion of the ram being solid still retains the disadvantages referred to caused by the internal stresses set up in it during the hardening operation where the main body portion is hardened to the desired degree.

The present invention provides a construction whereby the disadvantages of conventional and heretofore suggested constructions are eliminated in an exceptionally simple manner, it provides a construction wherein the main body portion or the ram may be hardened to an exceptionally high degree without developing any undue internal stresses'. provides the separate nose piece with all the advantages thereof, and provides a means of securing the nose piece to the main body portion of the ram Yso as to permit it to be separately machined and hardened and removed for replacement and yet such as to maintain the security of its connection with the main body portion or the ram for the life of the ram. To overcome the disadvantages of the conventional solid type ram arising because or the internal stresses in hardening above referred to, the ram provided in accordance with the present invention has a tubular or hollow mein body portion. The hollow shank or main body portion is of advantage for two reasons,

one of which is that it is stronger from a standpoint oi bending caused by columnar compression stresses than if it were solid, and the other is, that being hollow it is possible to harden it to higher physical pro erties because the hollow construction permits a more even hardness to be obtained throughout the wall thickness than in a solid ram and this also eliminates to a great extent the internal stresses, previously mentioned, which are set up in solid rams and wl'ii-ch cause preloading of the material thereof resulting in bending of the ram in service.

Referring now to the accompanying drawing and particularly to Fig. l the essential elements of an extruding press are more or less diagramvmatically illustrated as including a cylinder liner il for a cenventional cylinder (not shown), an extruding die i2 closing one end of the liner l@ and provided with an opening M therethrough which may be oi' any suitable or desirable cross'- sectional conguration and which determines the size and shape of the extruded work, a die ring it surrounding the extruding die l2, and a hacker plate 8 for the extruding die I2.v Within the liner lll is shown received a billet 2@ formed oi the material which it is desired to extrude in the press and while such material may be any one of a variety of dilerent metals or alloys, either ferrousI or non-ferrous, for the purposes of illustration only it may be assumed to be copper or brass and which is preferably brought to a temperature which may be around 1109" F. to 1200" F. for the purpose of and during the extruding operation. Received within the liner lil upon the upper end of the billet 20 is a so-ca1led dummy block 22 provided in accordance with conventional practice to prevent direct contact between the end of the extrusion ram and the heated billet 2Q, and the dummy block 22 is followed by the extrusion ram indicated generally at 2li, shown as constructed in accordance with the present invention and supported at its upper end in the ram 28 of a hydraulic press or other suitable pressure producing apparatus and maintained in place thereon by means of a clamping ring 28 overlying the ange 38 of the ram 24 and secured in position by means of bolts 32, It will be understood that in operation the ram 2li and dummy block 2E are removed from the liner i0, a billet 2!) is introduced into the liner and is followed by the dummy block 22 and ram 2li, the ram 24 exerting sumcient pressure through the dummy block 22 upon the billet 2l) to cause the billet 2li to be extruded through the opening M in the extruding die l2.

Referring now to Figs 2, 3 and i it will be noted that the ram 2li includes a main body portion or shank 34 of cylindrical construction throughout except at its attaching end which is slightly flared out as at 36 to the attaching fiange 3U, primarily for the purpose of added strength and rigidity at this point. The main body portion of the shank .'M is provided with an axial cylindrical opening 38 extending completely through it from end to end and the opening 3&5 isy enlarged as at 4i) at the flanged end of the main body portion or shank for a purpose which will hereinafter be more fully brought out. The ratio of the diameter of the main body portion 3d to the diameter of the bore 38 to obtain maximum columnar strength of the main body portion and yet reduce the occurrence of internal stresses in the material thereof in accordance with the present invention is preferably 5 to 1, although this ratio may vary between 4 to 1 and 6 to 1 and still obtain the advantage of the present construction. That end of the main body portion or shank 34 opposite the ange E@ is provided with a separate and removable nose piece 42 of the same diameter as the main portion of the shank 34 and arranged concentrioally therewith. For insuring such concentricity the bore 3S at the adjacent end of the main body portion 34 is enlarged to form a recess 44 and the nose piece 42 is provided with an axially projecting pilot 45 for relatively close reception therein, The length of the pilot 4G is less than the depth of the recess 44 so as to insure against contact of the end of the pilot with the bottom of the recess 44, and to limit the pressure transmitting faces between the main body portion 34 and the nose 42 to those surfaces thereof radially outwardly of the pilot 46. In order that these surfaces may be of maximum area so as to minimize as far as possible the unit pressure transmitted between said faces during an extruding operation, the recess 44 and pilot 4t? are, measured in a diametrical direction, made as small as is practically feasible. In order to prevent relative turning between the nose piece 42 and the main body portion 34, a relatively short dowel 43 is received in the opposed faces of these parts,

The length of the nose piece 42 is preferably less than its diameter where the nose piece is oi circular section, and less than a corresponding dimension where not of circular section, and preferably is approximately two-thirds as long as its greatest transverse dimension so as particularly to relieve the draw bolt, to be later described, from being subjected to bending stresses when the ram is operating on a billet having an inclined end face.

In order to secure the nose piece 42 to the main body portion 34, a draw bolt 50 extends through the bore :it in the main body portion 34 and is provided with a threaded end which is threadably received in a cooperating blind opening 52 i'orrned axially in the nose piece 42 and centrally of the pilot 46 thereon. The draw bolt 38 is preferably relatively loosely received in the bore 38 so as to remain out of actual contact therewith. The draw bolt 59 is provided with a head 54 which is received within the enlarged portion 4i? oi the bore 38 at the flanged end of the main body portion 34, the length of the head 54 being less than the length of the enlarged portion lil of the bore 33 so as not to project beyond the corresponding end face of the main body portion 34.

At least one and preferably a plurality or spring washers 56 are threaded on the draw bolt til and positioned between the head 54 of the draw bolt and the shoulder 58 formed at the junction of the bore 33 and the enlarged portion 40 thereof. The head 54 of the drawbolt 59 is provided with a plurality of peripheral serrations or notches til, as best indicated in Fig. 3, for the purpose oi receiving a wrench with which to rotate the draw bolt. In practice after the nose 42 has been applied and locked against rotation by means of the dowel pin 48, the draw bolt lil) is inserted into the bore and threaded into the opening 52 in the nose 42 and the draw bolt Elli is drawn up to such an extent as to place the spring washers 56 under a material tension but not to such an extent as to completely hatten such washers. The tension initially applied to the washer 56 in this manner, and

of course while the ram 24 is cold, is suicient to securely maintain the nose piece 42 in axial contact with the main body portion 34. In service, however, the main body portion 34 will heat up faster than the draw bolt 50 and will be axially elongated to a greater extent than the draw bolt 5B for this reason. This diierence in elongation between the main body portion 34 and the draw bolt 50 will be taken up by further springing of the washers 56 without subjecting the draw bolt 50 to any undue stresses. 'It will be appreciated that when the ram is thereafter cooled to room temperatures the spring washers 56 will act to restore the original force holding the nose 42 to the main body portion 34. It will be understood from the above that were the head 54 of the draw bolt 50 to seat directly against the shoulder 53 without the inter-position of spring washers 56 or the like, the main body p-ortion 34 might elongate to a suicient extent to stretch the draw bolt 50 beyond its elastic limit and to permanently elongate it, under which circumstances as soon as the ram 24 was cooled down, a looseness would develop between the nose piece 42 and the main body portion 34.

In order to prevent rotation of the draw bolt 50 and thereby prevent possible looseness from developing between the head 42 and main body portion 34 in service, the flanged end of the main body portion 34, as best illustrated in Fig. 3, is formed to provide a groove or keyway 62 in a side wall of the enlarged portion 4U of the bore 38, and in drawing up the draw bolt 50 the head 54 is turned so as to bring one of the slots Si! into registration with the'keyway 62, upon which a key t4 is driven into the keyway 62 and the aligned slot 60 to positively lock the draw bolt 5i) against relative rotation with respect to the main body portion 34.

Where the nose piece 42 becomes worn, scored or otherwise deformed in service to such an extent as to require replacement, all that is required is t0 remove the key G4, thus permitting removal of the draw bolt 5l) which automatically releases the nose piece 42 from the main body portion 34 and permits a new nose piece to be applied in its place. Particularly where the main body portion 34 is formed from a suitable material as hereinafter more fully described and is brought to the desired hardness, a number of diierent nose pieces 42 may be replaced on the rams without requiring any replacement or reservicing of the main body portion 34 itself. Also because the main body portion 34 and nose piece 42 are separable as described, each may be produced of a material especially adaptable to the work to be performed thereby, and independently hardened and tempered so as to obtain the best physical requirements of each, thus avoiding the disadvantages of the welded type of composite ram referred to above.

Because of the fact that the main body portion 34 is hollow it will be apparent that in the hardening step the liquid or air employed for chilling it will have access to the bore 38 as well as to the external surfaces. For this reason the material from which the main body portion 34 is made will be hardened to a materially greater uniformity than can be possible in a solid type of ram and the result is that the main body por- 'V' tion 34 may be hardened to a relatively high degree, namely, to 550 Brinell and higher without setting up such internal stresses in the material thereof as might endanger bending of the same under the circumstances above explained. In this connection it will be recalled that in solid rams it has been found that a hardness of 450 Brinell sets up such great internal stresses that the ram becomes permanently bent upon the occurrence of slight mis-alignments between the ram and cylinder. With the separate nose piece 42 which, when constructed of suitable material may be brought to a hardness of in the neighborhood of 600 Brinell, a completed ram is provided having the most desirable characteristics of a hard nose and a main body portion exhibiting maximum resistance to columnar stresses and at the same time highly resistant to both abrasion and wear.

One material suitable for forming the main body portion or shank 3Q in accordance with the present invention to obtain the desired characteristics above stated is of the following analysis, it being understood that the usual inclusions of sulphur, phosphorus and/ or other impurities may be present.

C .4S/.53 Mn .6G/.80 Si 15G/1.75 Va I .l/.14 Mo .35/.45 Fe Balance In constructing a main body portion or shank 3d from the above material the following constitutes the preferred steps of operation in its manufacture and heat treatment.

1. Forge 2. Normalize 3. Anneal 1475/1500 F.-l87 Brinell.

4. Finish bore and rough turn O. D.

5. Oil quench 1550 EH-600 Brinell 6. Draw at 750 F.-550 Brinell 7. Draw flanged end at 1000o ITK-450 Brinell 8. Finish turn or grind O. D.

A material of the following analysis may also be employed for the main body portion or shank 34.

C .QU/1.05 Mn .20/ .30 Si .20/ .30 Cr .45/ .55 Fe Balance In constructing a main body portion or shank 34 from the above material the following constitutes the preferred steps of operation in its manufacture and heat treatment.

. Forge Normalize Finish bore and rough turn O. D.

'Water quench 1525 F.-650 Brinell Draw at 600 F.-550 Brinell Draw flange-d end at 800 F.-450 Brinell Finish turn or grind O. D.

A material suitable for the formation of the nose piece 42 may have the following analysis:

C .30/ .40 Mn .30/ .40 Si LGO/1.75

Cr 6h00/6.00 Va .40/ .50

Fe Balance In constructing a nose piece l2 from the above material the following constitutes the preferred steps of operation in its manufacture and heat treatment.

1. Forge 2. Normalize 3. Anneal 1650o F.-220 Brinell 4. Drill-thread-rough turn and face 5. Oil quench 1950o 14".--600 Brinell 6. Draw at 1100/1150 F.-450 Brinell 7. Finish turn or grind and face.

A material of the following analysis may also be employed for the nose piece 42.

C 35/ .42 Mn 20/ .35 Si .6U/1.10 Cr LOD/1.50 W S35/4.25 Va .15/ .30 Fe Balance In constructing a nose piece 42 from the above material the following constitutes the preferred steps of operation in its manufacture and heat treatment.

. Forge Normalize Anneal 1600D F.-220 Brinell Drill-thread-rough turn and face Oil quench 1950 F.-600 Brinell Draw at l000 F.-450 Brinell Finish turn or grind and face.

A material for constructing the draw bolt 50 may have the following analysis.

C 40/. 50 Mn 25/ .35 Si .25/ .35 Cr 1.40/1.50 W 1.60/1 '75 Va .25/ .30 Fe Balance In constructing a draw bolt 50 from the above material the following constitutes the preferred steps of operation in its manufacture and heat treatment.

. Forge Normalize Anneal 1525 F.-207 Brinell Thread and machine splines in bolt head @DaNi- A material of the following analysis may also be employed for the draw bolt D.

C .35/ .40 Mn .65/ .80 Si 20/ .30 Cr .9C/1.10 Fe Balance In constructing a draw bolt 5U from the above material the following constitutes the preferred steps of operation in its manufacture and heat treatment.

. Forge Normalize Anneal 1550 F.-187 Brinell 'I'hread and machine splines in bolt head same or other suitable materials are employed, the hardness of the main body portion 34 and nose piece t2 in particular, (the draw bolt not being so important) may Vary above and below the limits of hardness specified, for instance, between 400 and 650 Brinell as determined by the particular material employed for these parts and/ or the heat treatment to which they are subjected.

Formal changes may be made in the specific embodiment of the invention described without departing from the spirit or substance of the broad invention, the scope of which is commensurate with the appended claims.

What I claim is:

1. A ram for an extruding press or the like comprising a main body portion having an axial bore extending completely therethrough, a nose piece of the same cross-sectional contour and size as said main body portion seated against an end oi said main body portion and closing said bore, means extending through said bore removably securing said nose piece and main body portion together, and yieldable means cooperating between the iirst mentioned means and said main body portion maintaining the effectiveness of the securing eiiect of said first mentioned means and guarding it against destructive forces due to elongation of said main body portion.

2. A ram for an extruding press or the like comprising a generally cylindrical hardened main body portion having a cylindrical axial bore therethrough of from one-quarter to one-sixth the diameter oi said main body portion, and a solid hardened cylindrical nose piece of the same general diameter as said main body portion removably secured to one end of said main body portion.

3. A ram for an extruding press or the like comprising a generally cylindrical hardened main body portion having a cylindrical axial bore therethrough of from one-quarter to one-sixth the diameter ci said main body portion, and a solid hardened cylindrical nose piece of the same general diameter as said main body portion and of no greater length than its diameter removably secured to one end of said main body portion.

4. A ram for an extruding press or the like comprising a main body portion and a nose piece removably secured to one end thereof, said main body portion having a central opening extending therethrough and being formed of a material oi a hardness between fr() and 650 Brinell over the greater portion of its length.

5. A ram for an extruding press comprising a hollow main body portion having a hardness of between 400 and 650 Brinell over the greater portion of its length, a separate solid nose piece 0f the same general diameter as said main body portion applied to one end of said main body portion, said nose piece having a hardness of between 400 and 650 Brinell, and means removably securing said nose piece and main body portion together.

6. A ram for an extruding press comprising a hollow main body portion having a hardness of approximately 560 Brinell over the greater portion of its length, a separate solid nose piece of the same general diameter as said main body portion applied to one end of said main body i portion, said nose piece having a hardness of approximately 450 Brineil, and means removably securing said nose piece and main body portion together.

7. A ram for an extruding press or the like comprising a generally cylindrical main body portion having a hardness of between 400 and 650 Brinell and having an axial bore extending therethrough of a diameter between one-quarter and one-sixth oi the diameter of said main body portion, a separate and solid nose piece of the same diameter as said main body portion and of a hardness between 400 and 650 Brinell, and means removably securing said nose piece in concentric relation to one end of said main body portion.

8. A ram for an extruding press or the like comprising a main body portion and a separable nose portion removably secured thereto, said `main body portion comprising a generally cylindrical member having an axial bore therethrough and formed of a material having a hardness between 400 and 65o Brinell and being free of excessive internal stresses when in free condition.

9. A ram for an extruding press or the like comprising a main body portion having an axial bore extending completely therethrough, a nose piece of the same cross-sectional contour and size as said main body portion seated against an end of said main body portion and closing said bore, a draw bolt extending through said bore and threaded into said nose piece removably securing said nose piece to said main body portion, means cooperating between said main body portion and said draw bolt locking them against relative rotation, and means cooperating between said nose piece and said main body portion locking them against relative rotation.

10. A ram for an extruding press or the like comprising a hollow main body portion and a separable nose portion, said portions having cooperating pilot and recess for maintaining the concentricity of said portions, and a draw bolt extending through the interior of said main body portion and cooperating with said nose portion to maintain said portions against inadvertent axial displacement.

11. A ram for an extruding press or the like comprising a generally cylindrical main body portion having a bore therethrough, a separable solid nose piece on one end of said main body portion, said bore being enlarged` at that end of said main body portion opposite said nose piece to form a recess, a draw bolt extending through said bore for removably securing said nose piece and main body portion together, a head on said draw bolt received in said recess, said head having a groove in a side thereof, the side wall of said recess having a groove therein, and a key received in both of said grooves for locking said draw bolt against relative rotation with respect to said main body portion.

12. A ram for an extruding press or the like comprising a generally cylindrical main body portion having a bore therethrough, a separable solid nose piece on one end of said main body portion, said bore being enlarged at that end of said main body portion opposite said nose piece to form a recess, a draw bolt extending through said bore for removably securing said nose piece and main body portion together, a head on said draw bolt received in said recess, a spring washer received on said draw bolt and maintained under stress between said head and the bottom of said recess, said head having a groove in a side thereof, the side wall of said recess having a groove therein, and a key received in both of said grooves for locking said draw bolt against relative rotation with respect to said main body portion.

CHARLES WALTER KRAUSE. n

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