US3350911A - Hydraulic tube extrusion press - Google Patents

Description

Nov. 7, 1967 H. H. GROOS 3,350911 HYDRAULIC TUBE EXTRUSION PRESS Filed VApril 26, 1967 2 Sheets-Sham l wm Nm @w mm .NN NNN NN Nm @N N. mN .NN

N k y? Q R N A Nov. 7, 1967 H. H. @Roos 3,350,911 HYDRAULIC TUBE EXTRUSION PRESS Filed April ze, 1967 2 sheetssheet 2 United States Patent O 3,350,911 HYDRAULIC TUBE EXTRUSION PRESS Horst Hans Groos, Metzkausen, Germany, assignor to Schloemann Aktiengesellschaft, Dusseldorf, Germany,

a company of Germany Filed Apr. 26, 1967, Ser. No. 633,983 Claims priority, application Germany, Dec. 6, 1962, Sch 32,434 Claims. (Cl. 72-265) ABSTRACT 0F THE DISCLOSURE The present hydraulic tube-extrusion press includes a stationary bolster, a stationary main cylinder cross-beam and rigid columns inter-connecting the cross-beam of the bolster. A billet container is arranged on the side of the bolster facing the cross-beam and a die holder and die are adapted to be clamped between the billet container and the bolster. A hollow extrusion ram which is co-axial with the die and the billet container is capable of axial movement relative to the die.

This application is a continuation in part of application Ser. No. 324,988 filed Nov. 20, 1963, now abandoned.

A longitudinally movable platen is secured to the ram and means are provided for forcing the platen and ram in a forward direction thereby extruding a billet from the container through the die.

Means are provided for piercing a billet prior to the extrusion thereof and such piercing means includes a mandrel slidable in the ram, a longitudinally slidable transverse cross-head for the mandrel, a longitudinally slidable piercing cylinder transverse cross-head, means rigidly connecting the piercing cylinder traverse crosshead with the platen, a piercing cylinder mounted in the piercing cylinder traverse cross-head behind the pressed cylinders, a piston slidable in the piercing cylinder and attached to the piercing mandrel traverse cross-head, means embodying a mandrel holder and an intermediate rod for transmitting a thrust from the piercing piston t0 the mandrel, mandrel returning means operable for effecting relative motion between the piercing cylinder traverse cross-head and the piercing mandrel traverse cross-head, and at least one hydraulic assemblage defined by a piston and cylinder, one of which components is operably relate to the main cylinder cross-beam and the other to the piercing cylinder traverse cross-head for retracting jointly the piercing cylinder traverse cross-head and platen.

The invention relates to a hydraulic tube extrusion press including billet piercing means which constitutes a longitudinally displaceable component with a platen carrying an extrusion ram.

This type of assemblage is particularly eicacious in that the stroke of the piercing means is restricted solely to the working stroke, and an additional idle stroke, such as is required in connection with fixed piercing devices arranged in a known fashion behind the main cylinder, is as a consequence completely unnecessary.

In the known constructions of this particular type, the piercing means have been accommodated within the platen of the press and the press has been made of a length sufcient to receive the piercing means. In this latter arrangement, the distance between the cylinder cross-beam and the counter-holder or bolster is greater by the length of the piercing means incorporated in the platen than on presses having the piercing means behind the cylinder cross-beam and as a consequence, the entire press is of considerable length.

A salient object of this invention is to provide a press which will overcome the above and other objectionable features existing in the art.

Another object of the invention is to provide a hydraulic tube extrusion press wherein for restricting the overall length of the press, the stroke of the piercing means is limited to the necessary working stroke of the mandrel.

In the area of the greatest pressing force, namely between the cylinder cross-beam and the bolster for obtaining a robust construction, a positive connection of the participating means is accomplished which is as short as in presses wherein the piercing means is arranged behind the cylinder cross-beam. In the present invention, this end is achieved by reason of the fact that the piercing means is arranged behind the main cylinder in a known fashion and is rigidly connected with the press platen with such connection preferably being by way of piercing traverse columns so that the piercing means is brought into its working position by the platen with the stroke remaining restricted merely to the actual working stroke.

It is further advantageous if the piercing cylinder traverse which carries the piercing cylinder is guided on a slideway and as a result, since the traverse cross-head constitutes a rigid iunit with the press platen canting or tilting of the latter is preventedY during operation.

According to a further development of the invention, the press platen returning means are connected directly to the piercing cylinder traverse cross-head so that additional traverses provided with slideways and the required return linkage to the press platen or the otherwise customary differential pistons with their double packing spaces may be eliminated.

According to the invention the piercing cylinder traverse cross-head and a piercing traverse for guiding the mandrel holder are preferably provided with a. commonslideway which, in a manner known per se, is of the usual prismatic type, namely the guide surfaces on opposite sides of the press are inclined in opposite directions and in such a fashion as not to hinder the expansion vand contraction, under the influence of temperatures, of the members sliding thereon. The slideway for the platen is similarly constructed for ensuring a precisely central position and a sleeve is secured on the platen for guiding the mandrel holder and for limiting the piercing stroke.

Further objects and advantages of the invention will become more readily apparent to persons skilled in the art from the following detailed specification and annexed drawings, and in which drawings:

FIGURE 1 is a longitudinal view partly in elevation and partly in cross-section of a multi-cylinder tube press in the starting position, t

FIGURE 2 is a longitudinal view partly in elevation Y and partly in ,cross section of the press in the working position and with the piercing mandrel and extrusion ram advanced,

FIGURE 3 is a view of the press looking in the direction of the arrow A in FIGURE l, and

FIGURE 4 is a sectional view taken along the line IV-IV of FIGURE 1, the view looking in the direction of the arrows.

From the drawings it will be seen that the press is provided with a stationary main cylinder cross-beam 1 and a bolster or counter-holder 2 which is rigidly connected with the cross-beam by means of columns 3. A longitudinally displaceable billet container 4 is arranged on the side of the bolsterV facing the cross-beam 1 and is pnovided with means (not shown) for clamping adie 5 and a die holder 6 against the bolster 2. A hollow `extrusion ram 7 capable of movement toward the die S and located on a common axis 8 with the die is secured to a 3 platen 9. The platen 9 is longitudinally displaceable on slideways 10. Press pistons 11 of four press cylinders arranged in the main cylinder cross-beam 1 symmetrically about the center of the press are connected with the platen 9. The upper and lower cylinders are denoted 11a and those to the left and right 11b. Moreover, the platen 9 is connected by four piercing traverse columns 12 with a piercing cylinder traverse cross-head 13 located behind the cylinders 11a and guided upon slideways 14. Consequently, the platen 9 constitutes, together with the columns 12 and the traverse cross-head 13, a longitudinally displaceable rigid unit. It will ybe noted that the press pistons 11 of the upper and lower cylinders 11a are hollow vand the return cylinders 15 project into the hollow pistons 11 and the cylinders 15 are rigidly connected with press cylinders 11a. Piston rods 16 bear against the traverse cross-head 13.

A piercing mandrel 17 arranged in the hollow ram 7 is supported by an intermediate rod 18 and a mandrel holder 19 in a piercing mandrel traverse cross-head 20 located between the cross-beam 1 and the traverse crosshead 13. This component is slidably guided upon the slideway 14. The mandrel 17 is moved forwardly by a piston 21 of a piercing cylinder 22 secured in the traverse crosshead 13. The retraction of the mandrel 17 is effected by a mandrel return means 23 located in the traverse crosshead 13 and connected with the traverse cross-head 20. In the present situation, the means 23 is dened by four hydraulically operable cylinders symmetrically arranged about the piercing cylinder 22.

In FIGURES 3 and 4, it will be seen that the slideways and 14 serving for guiding the platen 9, traverse cross-head 13 and traverse cross-head 20 are defined as plane guiding surfaces located on both sides beneath the level of the axis 8 of the press and directed toward the latter. As a consequence, notwithstanding thermal expansion of the components sliding thereupon, the axes of said components are held in the axis 8 of the press.

To assure a better guiding of the mandrel 17 and the mandrel holder 19, a sleeve 24 is flanged to the platen 9 and end face 25 of the sleeve, together with a ring 26 mounted on holder 19 constitute a stroke limiting means for the piercing means as an entity. The mandrel 17 is additionally connected with the intermediate rod 18 by means of a coupling 27 which at the same time constitutes a guide for the mandrel 17 in the extrusion ram 7. The supply and discharge of the pressure liquid to and from the cylinders 11a and 11b is as diagrammatically illustrated in FIGS. l and 2 by way of pressure pipes or conduits 30, 31, 32 and 33 which are connected with control valve means 34, 35, 36 and 37 respectively. The control valve means are each connected by a second port 'or aperture to a main inlet pipe or conduit 28 and by a third port or aperture to a main outlet pipe or conduit 39. The diagrammatic illustration of the control valve means merely serves for illustrating the direction of flow of the pressure liquid in the existing working position of the press.

The operation of the press is as follows:

Prior to the charging of the container 4 with a billet 28 to be extruded, the press is in the initial position illustrate-d in FIGURE 1 and in which a billet loader (not shown) brings the billet 28 and a press plate 29 to the axis 8 of the press. The position of the control valve means in FIG. 1 corresponds to the last phase of the retraction of the press. The control valve means 35 connected with the mandrel return cylinder is shown in the admission position, whereas control valve means 34 connected with the cylinder 11a is in the exhaust position. The remaining valve means 36 and 37 are closed during this particular operation.

The billet 28 together With the plate 29 is now pushed or forced into the billet container 4. To accomplish this end, the control valve means 34 is manipulated to its admission position an-d the control valve -rneans 35 to the exhaust position so that ram 7 by virtue of the advance of the piston 11 pushes the billet 28 into the container 4. Due to the fact that the traverse cross-head 13 via the columns 12 provide a rigid unit with the platen 9, the piercing means, during the aforementioned pushing operation, is carried along toward the container 4. Following a slight upsetting of the billet 28 and a slight retraction of the ram 7, the billet 28 is pierced. This is achieved by supplying liquid into the piercing cylinder 22, through control valve means 37 adjusted to the admission position, the control valve means 36 connected to the mandrel return means 23 being at the same time in the exhaust position.

After the piercing operation, the billet 28, is forced by the ram 7 through the free space or hiatus between the die 5 and the mandrel 17, with the individual control valve means being shifted according to the working position of the press illustrated in FIGURE 2. Upon the conclusion of the extrusion operation, the press cylinders 11a and 11b are relieved of pressure and the mandrel 17 returned or drawn `back to its initial position. Thereupon, the ram 7 is likewise retracted by supplying pressure liquid to the return cylinder 15 according to the position of the control valve means disclosed in FIGURE 1.

The invention is not to be confined to any strict conformity to the showings in the drawings but changes or modificati-ons may be made therein so long as the changes or modifications mark no material departure from the spirit and scope of the appended claims.

I claim:

1. A hydraulic tube extrusion press including a stationary bolster, a stationary main cylinder cross-beam, rigid columns connecting said main cylinder cross-beam with said bolster, a billet container arranged on the side of said bolster facing said main cylinder cross-beam, a die holder and a die adapted to be clamped between the billet container and the bolster, a hollow extrusion ram coaxial with said die and said 4billet container with said ram being movable axially relatively to said die, a longitudinally movable platen secured to said ram, stationary press cylinders mounted in said main cylinder cross-beam, press pistons slidable in said press cylinders and adapted upon admission of liquid under pressure into said cylinders to force said Platen and ram forwardly thereby extruding a billet from said container through said die, and means for piercing a billet prior to extrusion thereof and said piercing means comprising, a mandrel slidably mounted in said extrusion die, a longitudinally slidable piercing mandrel traverse cross-head, a longitudinally slidable piercing cylinder traverse cross-head, columns rigidly connecting said piercing cylinder traverse cross-head with said platen, a piercing cylinder mounted in said piercing cylinder traverse cross-head behind said press cylinder, a piercing piston slidably mounted in said piercing cylinder and secured to said piercing mandrel traverse cross-head, means for transmitting a thrust from said piercing piston to said man-drel, mandrel returning means for causing relative motion between said piercing cylinder traverse cross-head, and at least one hydraulic means including piston and cylinder components, one of which components is attached to said main cylinder cross-beam and the other of said components to said piercing cylinder traverse cross-head for retraction of said piercing cylinder traverse cross-head and said platen jointly.

2. The hydraulic tube extrusion press as claimed in claim 1 in which said means for transmitting a thrust from said piercing piston and said mandrel includes a mandrel holder and an intermediate rod.

3. The hydraulic tube extrusion press as claimed in claim 1 further including slideways for guiding said platen piercing mandrel traverse cross-head and piercing cylinder traverse cross-head, said slideways being located one on each side of the axis of the press below the level of said press axis and the surfaces of said slideways being inclined at such an angle as not to hamper the expansion and contraction of such components under the influence of temperature changes.

4. The hydraulic tube extrusion press as claimed in claim 1 in which the hydraulic piston and cylinder means for the joint retraction of said piercing cylinder traverse Cross-head and said platen include return cylinders rigidly connected with and projecting into at least some of said press cylinders and return pistons and piston rods slidable in said return cylinders with such return piston rods when activated bearing against said piercing cylinder traverse cross-head.

5. The hydraulic tube extrusion press as claimed in claim 1 further including a sleeve secure-d to said platen for guiding said thrust transmitting means, and a stroke limiting ring mounted upon said thrust transmitting means adapted to bear against one end face of said sleeve during the advance of said mandrel for limiting the stroke of said mandrel.

References Cited UNITED STATES PATENTS 3,124,250 3/1964 Krause 72-272 3,127,013 3/1964 Dohrn 72--272 3,197,994 8/1965 Samuel et al. 72--272 CHARLES W. LANHAM, Primary Examiner. H. D. HOINKES, Assistant Examiner.1

Claims (1)

1. A HYDRAULIC TUBE EXTRUSION PRESS INCLUDING A STATIONARY BOLSTER, A STATIONARY MAIN CYLINDER CROSS-BEAM, RIGID COLUMNS CONNECTING SAID MAIN CYLINDER CROSS-BEAM WITH SAID BOLSTER, A BILLET CONTAINER ARRANGED ON THE SIDE OF SAID BOLSTER FACING SAID MAIN CYLINDER CROSS-BEAM, A DIE HOLDER AND A DIE ADAPTED TO BE CLAMPED BETWEEN THE BILLET CONTAINER AND THE BOLSTER, A HOLLOW EXTRUSION RAM COAXIAL WITH SAID DIE AND SAID BILLET CONTAINER WITH SAID RAM BEING MOVABLE AXIALLY RELATIVELY TO SAID DIE, A LONGITUDINALLY MOVABLE PLATEN SECURED TO SAID RAM, STATIONARY PRESS CYLINDERS MOUNTED IN SAID MAIN CYLINDER CROSS-BEAM, PRESS PISTONS SLIDABLE IN SAID PRESS CYLINDERS AND ADAPTED UPON ADMISSION OF LIQUID UNDER PRESSURE INTO SAID CYLINDERS TO FORCE SAID PLATEN AND RAM FORWARDLY THEREBY EXTRUDING A BILLET FROM SAID CONTAINER THROUGH SAID DIE, AND MEANS FOR PIERCING A BILLET PRIOR TO EXTRUSION THEREOF AND SAID PIERCING MEANS COMPRISING, A MANDREL SLIDABLY MOUNTED IN SAID EXTRUSION DIE, A LONGITUDINALLY SLIDABLE PIERCING MANDREL TRAVERSE CROSS-HEAD, A LONGITUDINALLY SLIDABLE PIERCING CYLINDER TRAVERSE CROSS-HEAD, COLUMNS RIGIDLY CONNECTING SAID PIERCING CYLINDER TRAVERSE CROSS-HEAD WITH SAID PLATEN, A PIERCING CYLINDER MOUNTED IN SAID PIERCING CYLINDER TRAVERSE CROSS-HEAD BEHIND SAID PRESS CYLINDER, A PIERCING PISTON SLIDABLY MOUNTED IN SAID PIERCING CYLINDER AND SECURED TO SAID PIERCING MANDREL TRAVERSE CROSS-HEAD, MEANS FOR TRAMSMITTING A THRUST FROM SAID PIERCING PISTON TO SAID MANDREL, MANDREL RETURNING MEANS FOR CAUSING RELATIVE MOTION BETWEEN SAID PIERCING CYLINDER TRAVERSE CROSS-HEAD, AND AT LEAST ONE HYDRAULIC MEANS INCLUDING PISTON AND CYLINDER COMPONENTS, ONE OF WHICH COMPONENTS IS ATTACHED TO SAID MAIN CYLINDER CROSS-BEAM AND THE OTHER OF SAID COMPONENTS TO SAID PIERCING CYLINDER TRAVERSE CROSS-HEAD FOR RETRACTION OF SAID PIERCING CYLINDER TRAVERSE CROSS-HEAD AND SAID PLATEN JOINTLY.

Images