POSITIVE STOP SYSTEMS AND METHODS FOR EXTRUSION PRESS

Abstract

Systems, devices, and methods are described for extruding a material. In certain embodiments, an extrusion press system includes an extrusion die supported by a first support structure and a centering insert supported by a second support structure, wherein the centering insert guides a material to be extruded into the extrusion die. A positive stop may be coupled to the first support structure and extend towards the second support structure, wherein the positive stop defines a travel distance between the first support structure and the second support structure. In certain embodiments, movement of the second support structure towards the first support structure is limited by the positive stop to the travel distance. In certain embodiments, the positive stop is configured to adjust the travel distance.

Description

BACKGROUND

Deformation is the process of forcing a piece of material to permanently change its thickness or shape, and some deformation techniques include forging, rolling, extruding, and drawing. Deformation of a material typically generates heat. In the context of extrusion processes, excess heat at the interface between two components can contribute to wear and result in the production of flash, where flash is the undesirable passage of the extrusion material through clearance spaces between the two components. Present systems thus have limited operational run times because of the generation of excess heat and associated problems.

SUMMARY

Disclosed herein are systems, devices, and methods for extruding a material. In certain embodiments, the systems, devices, and methods include a positive stop between the extrusion die and a component positioned against the extrusion die. In certain embodiments, the extrusion die is a rotating extrusion die. The positive stops may reduce and/or eliminate the occurrence of flash at an interface between the extrusion die and the component. For example, the positive stops may reduce the amount of heat at the interface. In some embodiments the component is a centering insert that guides a material to be extruded into the rotating extrusion die.

In one aspect, the systems, devices, and methods include an extrusion press system comprising an extrusion die supported by a first support structure, a centering insert supported by a second support structure, wherein the centering insert guides a material to be extruded into the extrusion die, and a positive stop coupled to the first support structure and extending towards the second support structure, wherein the positive stop defines a travel distance between the first support structure and the second support structure. In certain implementations, the extrusion die rotates within the first support structure, and the centering insert is positioned against the extrusion die and does not rotate. The centering insert may include gripping features that frictionally engage the material to be extruded and thereby prevent the material from rotating while engaged and as the material enters the rotating extrusion die. In certain implementations, the extrusion press system further comprises a second positive stop.

In certain implementations, the first support structure is stationary, the second support structure is configured to move relative to the first support structure, and movement of the second support structure towards the first support structure is limited by the positive stop to the travel distance. In certain implementations, the centering insert is a consumable part that is partially consumed when the second support structure moves towards the first support structure a distance of the travel distance. In certain implementations, the travel distance is between about zero inches and about 100/1000 inch. In certain implementations, the travel distance is between about 10/1000 inch and about 50/1000 inch. In certain implementations, the travel distance is between about 10/1000 inch and about 30/1000 inch. In certain implementations, the travel distance is about 20/1000 inch.

In certain implementations, the positive stop is configured to adjust the travel distance. For example, the positive stop may include an adjustable portion that rotates about a threaded shaft for increasing or decreasing the travel distance. In certain implementations, the positive stop comprises an adjustable portion that slides along a shaft for increasing or decreasing the travel distance. In certain implementations, the positive stop comprises a recess configured to mate with a plurality of end portions, each respective end portion having a respective thickness for increasing or decreasing the travel distance. In certain implementations, the positive stop further comprises a through-hole into which a locking pin is positioned.

In one aspect, a method for extruding a material is provided that includes positioning a centering insert in a first position against an extrusion die, exerting a force on the centering insert to maintain a desired pressure of the centering insert against the extrusion die, wherein the force moves the centering insert from the first position to a second position, and preventing further movement of the centering insert at the second position. In certain implementations, upon preventing further movement, a pressure of the centering insert against the extrusion die decreases relative to the desired pressure. In certain implementations, the force continues to be exerted while movement of the centering insert is prevented at the second position. In certain implementations, a distance between the first position and the second position defines a travel distance. In certain implementations, the method further includes adjusting the travel distance. In certain implementations, the extrusion die rotates, and the centering insert does not rotate.

In one aspect, an extrusion press system is provided that comprises extrusion means supported by a first support structure, guiding means for guiding a material to be extruded into the extrusion means, the guiding means supported by a second support structure, and means for limiting movement of the second support structure with respect to the first support structure. In certain implementations, the extrusion means rotates within the first support structure, and the guiding means is positioned against the extrusion means and does not rotate. The guiding means may include gripping features that frictionally engage the material to be extruded and thereby prevent the material from rotating while engaged and as the material enters the rotating extrusion means. In certain implementations, the extrusion press system further comprises a second means for limiting movement of the second support structure with respect to the first support structure.

In certain implementations, the first support structure is stationary, the second support structure is configured to move relative to the first support structure, and movement of the second support structure towards the first support structure is limited by the limiting means to a travel distance. In certain implementations, the guiding means comprises a consumable part that is partially consumed when the second support structure moves towards the first support structure a distance of the travel distance. In certain implementations, the travel distance is between about zero inches and about 100/1000 inch. In certain implementations, the travel distance is between about 10/1000 inch and about 50/1000 inch. In certain implementations, the travel distance is between about 10/1000 inch and about 30/1000 inch. In certain implementations, the travel distance is about 20/1000 inch.

In certain implementations, the limiting means is configured to adjust a travel distance. For example, the limiting means may include an adjustable portion that rotates about a threaded shaft for increasing or decreasing the travel distance. In certain implementations, the limiting means comprises an adjustable portion that slides along a shaft for increasing or decreasing the travel distance. In certain implementations, the limiting means comprises a recess configured to mate with a plurality of end portions, each respective end portion having a respective thickness for increasing or decreasing the travel distance. In certain implementations, the limiting means further comprises a through-hole into which a locking pin is positioned.

Variations and modifications of these embodiments will occur to those of skill in the art after reviewing this disclosure. The foregoing features and aspects may be implemented, in any combination and subcombination (including multiple dependent combinations and subcombinations), with one or more other features described herein. The various features described or illustrated herein, including any components thereof, may be combined or integrated in other systems. Moreover, certain features may be omitted or not implemented.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects and advantages will be apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout, and in which:

FIG. 1 shows a schematic side elevation view of illustrative positive stops in an extrusion press system according to certain embodiments;

FIGS. 2-4 show various side elevation views of illustrative adjustable positive stops for the extrusion press system of FIG. 1 according to certain embodiments; and

FIG. 5 shows a side elevation view of an illustrative extrusion press system that includes positive stops according to certain embodiments.

DETAILED DESCRIPTION

To provide an overall understanding of the systems, devices, and methods described herein, certain illustrative embodiments will be described. Although the embodiments and features described herein are specifically described for use in connection with extrusion press systems, it will be understood that all the components, connection mechanisms, manufacturing methods, and other features outlined below may be combined with one another in any suitable manner and may be adapted and applied to systems to be used in other manufacturing processes, including, but not limited to cast-and-roll, up-casting, other extrusion, and other manufacturing procedures. Furthermore, although certain embodiments described herein relate to extruding metal tubing from hollow billets, it will be understood that the systems, devices, and methods herein may be adapted and applied to systems for extruding any suitable type of product.

The extrusion press system operates using frictional heat generated from a non-rotating hollow billet contacting a rotating die to facilitate deformation and extrusion of the billet. There is thus no requirement of pre-heating the billets or the rotating die before the extrusion. The amount of heat generated is generally determined by the rate at which the billets are fed into the rotating die (e.g., controlled by the press-ram speed of the press-ram elements 130, 140 of FIG. 5) and the rotation speed of the die (e.g., controlled by the rotation speed of the spindle 172 of FIG. 5), as well as the interior profile of the rotating die. Higher press-ram speeds and spindle rotation speeds generate relatively greater amounts of heat.

The rotating die forms the outer diameter of an extruded tube produced by the extrusion press system, and a mandrel bar tip positioned within the rotating die forms the inner diameter of the extruded tube. In certain embodiments, chilled process water, or any other suitable cooling fluid, is used to cool the process elements including the rotating die, the centering insert, the billets, and the gear box oil, as well as the extruded tubing product. Unlike conventional extrusion techniques, the extrusion press system of the present disclosure does not require any container within which to hold the billet for extrusion. Therefore the billets to be extruded preferably have sufficient column strength to withstand the pressure applied by the press-ram elements during the extrusion process. A programmable logic controller, or PLC, controls all or a subset of movements of the extrusion press system while the system is set in automatic mode.

FIG. 1 shows a schematic side elevation view of positive stops 30, 40 in an extrusion press system 5 according to certain embodiments. The extrusion press system 5 includes an extrusion die 10 supported by a die-backer plate or support structure 12. In some embodiments, the extrusion die 10 rotates within the support structure 12. For example, the extrusion die 10 may be coupled to a spindle (e.g., spindle 172 of FIG. 5) operated by a motor. A centering insert 20 is positioned against the extrusion die 10 and supported by a platen or support structure 22. The centering insert 20 guides a material to be extruded into the extrusion die 10. For example, the centering insert 20 is hollow along its length so that the material to be extruded passes through the centering insert 20 before entering the extrusion die 10. The centering insert 20 preferably does not rotate. In some embodiments, the centering insert 20 has one or more gripping features (e.g., teeth, grooves, or other detents) that frictionally engage the material to be extruded and thereby prevent the material from rotating while engaged.

As shown in FIG. 1, a positive stop 30 is coupled to the first support structure 12 and extends towards the second support structure 22, with a gap 34 of distance d₁ between a contact surface 30a of the positive stop 30 and a contact surface 22a of the second support structure 22. During operation, the first support structure 12 is stationary and the second support structure 22 moves relative to the first support structure 12. For example, one or more piston/cylinder drive units may be coupled to the support structure 22 to advance and optionally retract the structure. In certain embodiments, the second support structure 22 moves in a direction towards the first support structure 12 (along arrow A) and a direction away from the first support structure (opposite arrow A). The positive stop 30 therefore defines a travel distance d₁ between the respective support structures 12, 22. Although the positive stop 30 is shown as coupled to and extending from the first support structure 12 towards the second support structure 22, other configurations may be used. For example, in some embodiments, a positive stop may be coupled to the second support structure 22 and extend towards the first support structure 12, with a gap between respective contact surfaces of the positive stop and first support structure 12. Any suitable arrangement for preventing motion of one (or more) of the support structures may be used.

The movement of the second support structure 22 towards the first support structure 12 is limited by the positive stop 30 to the travel distance d₁. That is, the positive stop 30 acts as a physical stop or barrier to the movement of the support structure 22. During operation, for example, the centering insert 20 is positioned against the extrusion die 10 as shown in FIG. 1. From that position, the second support structure 22 can move (together with the centering insert 20) towards the first support structure 12 by a distance up to the travel distance d₁. For example, in some embodiments, the centering insert 20 is a consumable part that is partially consumed when the second support structure 22 moves towards the first support structure 12 by a distance up to the travel distance. In some embodiments, whether or not any components are consumable, compression of the respective components (e.g., the adjacent die 10/insert 20) allows for movement of the support structure 22 by a distance up to the travel distance.

As discussed above, the extrusion die 10 may be a rotating extrusion die, and the centering insert does not rotate, but serves to guide a material to be extruded into the rotating extrusion die. The centering insert 20 is positioned against the extrusion die 10 to minimize any clearance between the two components. A force is exerted on the centering insert 20 (e.g., by way of the support structure 22) to maintain a desired pressure of the centering insert 20 against the extrusion die 10 during operation. This applied pressure maintains a seal between the two components. It is desirable to spread the work done by the extrusion die across the length of the die to avoid the generation of excess heat at the entrance of the extrusion die. In some embodiments, however, the amount of pressure applied can cause undesirable heat generation at the interface of the centering insert 20 and the extrusion die 10 (e.g., because the extrusion die 10 rotates and the centering insert 20 does not rotate). Such heat can prematurely heat the material being extruded as it enters the die, causing a “flash” of the material, where flash is the undesirable passage of the extrusion material through clearance spaces between the extrusion die and the centering insert.

The positive stop 30 reduces flash and/or other undesirable heat generated at the entrance of the die by preventing movement of the centering insert relative to the rotating extrusion die after a given amount of travel. For example, the force exerted on the centering insert 20 can move the centering insert 20 along the direction of arrow A from a first position (e.g., shown in FIG. 1) to a second position (e.g., displacement of travel distance d₁). At the second position, the positive stop 30 prevents further movement of the centering insert 20 (notwithstanding, in some embodiments, the continuous application of force at that position). Any suitable travel distance may be used in the extrusion press systems of the present disclosure, including, for example, a travel distance of zero when the positive stop is positioned against the centering insert. In some embodiments, the travel distance is between zero inches and 100/1000 inch. In some embodiments, the travel distance is between 10/1000 inch and 50/1000 inch. In some embodiments, the travel distance is between 10/1000 inch and 30/1000 inch. For example, a travel distance of 20/1000 inch has been used in extrusion press systems for the continuous and uninterrupted extrusion of materials.

When the centering insert 20 reaches the second position and further movement is prevented, the pressure of the centering insert 20 against the extrusion die 10 decreases relative to the pressure exerted while the centering insert 20 was moving. This decreased pressure is enough to allow for continuous extrusion of a material (e.g., there is a sufficient seal between the centering insert and the extrusion die), yet reduced enough to prevent the generation of excess heat that can lead to unwanted flash. Moreover, this decreased pressure can increase the life of various components of the extrusion press system 5. For example, the centering insert 20 is typically a consumable part, and during operation, portions of the extrusion die 10 may also be consumed. Absent a positive stop, the force exerted on the centering insert 20 to maintain pressure on the extrusion die 10 may cause a substantial portion of the centering insert 20 and/or extrusion die 10 to be consumed as a result of frictional contact, in some cases leading to a halt in the extrusion process to replace the part(s). Limiting the travel distance of the centering insert, however, allows for minimal, if any, consumption of the part(s). In certain embodiments, some consumption of the centering insert and/or extrusion die 10 is desirable because controlled heat deformation of the centering insert and/or extrusion die 10 at the interface with the die may contribute to the seal between the rotating extrusion die and the non-rotating centering insert.

In some embodiments, a single positive stop may be used to limit the movement of a support structure. In some embodiments, more than one positive stop may be used to limit the movement of a support structure. For example, as shown in FIG. 1, a second positive stop 40 in the extrusion press system 5 is coupled to the first support structure 12 and extends towards the second support structure 22, with a gap 36 of distance d₂ between a contact surface 40a of the positive stop 40 and a contact surface 22b of the second support structure 22. The contact surfaces 22a/22b of the second support structure 22 are shown as being part of the same planar surface 22c of the support structure, although any surfaces could be used, so long as the gap distances d₁ and d₂ (e.g., the amount of travel) are preferably the same. This prevents the positive stops 30, 40 from causing different portions of the structure to move different amounts. For example, in some embodiments, the two positive stops 30, 40 may have different respective lengths, yet the allowed travel distances d₁ and d₂ are the same. Although two positive stops 30, 40 are depicted, it will be understood that any suitable number of positive stops may be provided to limit the travel distance of a support structure. Furthermore, the positive stops may be provided in any suitable arrangement. For example, in a system having three positive stops, each of the positive stops may be spaced about the extrusion die 10 in a generally triangular pattern.

In some embodiments, the travel distance (e.g., travel distance d₁ and d₂) may be adjusted prior to or during operation of the extrusion press system 5. For example, prior to operation, the positive stops 30, 40 may be removed and replaced with positive stops allowing a different respective travel distance. In some embodiments, prior to or during operation, the positive stops are configured to adjust the travel distance. As shown in FIG. 2, a positive stop 300 includes a first portion 302 and a second portion 304. The second portion 304 is an adjustable portion that, when adjusted, changes the respective travel distance allowed by the positive stop 300. For example, the adjustable portion 304 can rotate about a threaded shaft 306 to increase or decrease the travel distance allowed by the contact surface 304a of the positive stop 300. There are many variations of positive stops having an adjustable portion. For example, as shown in FIG. 3, a positive stop 310 includes a first portion 312 and a second portion 314. The second portion 314 is an adjustable portion that, when adjusted, changes the respective travel distance allowed by the positive stop 310. The adjustable portion 314 can slide along a shaft 316 to any position along the shaft. In some embodiments, the shaft 316 has a plurality of holes 317 that align with a respective through-hole 319 in the adjustable portion 314. When aligned, a locking pin 318 may be placed within the through-hole 319 to secure the adjustable portion 314 in place with the hole 317. In some embodiments, a similar locking mechanism may be used with the positive stop 300 discussed above for preventing rotation of the adjustable portion 304, when locked, about the threaded shaft 306.

In some embodiments, a positive stop is configured to adjust a given travel distance without an adjustable portion. For example, as shown in FIG. 4, a positive stop 320 comprises a first portion 322 that optionally receives removable end portions. The first portion 322 has a recess 324 formed in a distal end 322a thereof that is configured to mate with a plurality of end portions 326, 328, each respective end portion having a respective thickness for increasing or decreasing the travel distance allowed by the positive stop 320. End portion 326 has a contact surface 326a and a connector 327 that is received within the recess 324. End portion 328 similarly has a contact surface 328a and a connector 329 that is received within the recess 324. The end portions 326, 328 have different respective thicknesses t₁, t₂ that changes the respective travel distance allowed by the positive stop 320. When no end portion is used, the positive stop 320 has yet another travel distance allowed by the contact surface 322a of the first portion 322. In some embodiments, a similar locking mechanism to that discussed above in connection with FIG. 3 may be used with the positive stop 320 for preventing removal, when locked, of the end pieces.

As discussed above, the positive stops may be configured to adjust the travel distance during operation of the extrusion press system. In some embodiments, the adjustable portion of the positive stop (e.g., adjustable portions 304, 314) can be adjusted manually or using the PLC system to change the travel distance without interruption of the extrusion process. Manual adjustment may be done by hand or by using tools to prevent the risk of injury. Adjustment using the PLC system is automatic or in response to an operator request, and may cause the adjustment of adjustable portions that are electro-mechanically controlled (e.g., a piston-cylinder arrangement). Thus adjustment of the travel distance may be done at any time during operation of the extrusion press system. In some embodiments, the travel distance can be increased stepwise during operation. A first travel distance is set and a support structure moves by the first travel distance until it contacts the positive stop. After a suitable amount of time, the travel distance may be increased to a second travel distance, and the support structure again moves until contacting the positive stop. Further stepwise (or continuous) adjustments to the travel distance can be made at any time. This allows an operator to control, throughout the extrusion process, the heat generated at the interface between components of the extrusion press system (e.g., the extrusion die 10 and the centering insert 20).

The positive stops of the present disclosure (e.g., positive stops 30, 40, 300, 310, 320) may be used for forming an extruded material in any suitable system including, for example, the extrusion press systems described in U.S. patent application Ser. No. 13/650,977, filed Oct. 12, 2012, the disclosure of which is hereby incorporated by reference herein in its entirety. For example, positive stops 154, 156 may be incorporated into the extrusion press system of FIG. 5, which shows an extrusion press system 200 according to certain embodiments. The extrusion press system 200 includes a mandrel carriage section 280 and a platen structure section 290. The mandrel carriage section 280 includes a mandrel bar 100, fluid clamps or cooling elements 102 and 104, mandrel grips or gripping elements 106 and 108, and a billet delivery system. The mandrel carriage section 280 is supported by a physical carriage structure, which is not shown in FIG. 5 to avoid overcomplicating the drawing, but which carriage structure serves as a mount for the components of the mandrel carriage 280. The platen structure section 290 includes an entry platen 120 and a rear die platen 122, press-ram platens 130 and 140, a centering platen 152, and a rotating die 160 that presses against the rear die platen 122. The platen structure section 290 is supported by a frame 190 that may also serve as a mount for the motor 170 and related gearbox components (not shown). The direction along which billet loading, transport, and extrusion occurs according to the extrusion press system 10 is denoted by arrow B. The extrusion press system 200 may be operated, at least in part, by a PLC system that controls aspects of the billet delivery subsystem 220, extrusion subsystem 240, and quenching or cooling subsystem 260 of the extrusion press system 200.

The mandrel grips 106, 108 comprise a mandrel bar gripping system 105 designed to hold the mandrel bar in place while allowing a plurality of billets to be continuously fed along and about the mandrel bar 100 to provide for continuous extrusion. The billets may be formed from any suitable material for use in extrusion press systems including, but not limited to, various metals including copper and copper alloys, or any other suitable non-ferrous metals such as aluminum, nickel, titanium, and alloys thereof, ferrous metals including steel and other iron alloys, polymers such as plastics, or any other suitable material or combinations thereof. The mandrel grips 106, 108 may be controlled by the PLC system to securely hold in place and prevent the mandrel bar 100 from rotating such that at any given time during the extrusion process, at least one of the mandrel grips 106, 108 is gripping the mandrel bar 100. The mandrel grips 106, 108 set the position of the mandrel bar 100 and prevent the mandrel bar 100 from rotating. When the mandrel grips 106, 108 are in a gripping or engaged position, thereby gripping the mandrel bar 100, the mandrel grips 106, 108 prevent billets from being transported along the mandrel bar 100 through the grips.

The mandrel grips 106, 108 operate by alternately gripping or engaging the mandrel bar 100 to allow one or more billets to pass through a respective mandrel grip at a given time. For example, the upstream mandrel grip 106 may release or disengage the mandrel bar 100 while the downstream mandrel grip 108 is gripping the mandrel bar 100. At any given time, at least one of the mandrel grips 106, 108 is preferably gripping or otherwise engaged with the mandrel bar 100. One or more billets queued or indexed near the upstream mandrel grip 106, or being transported along the mandrel bar 100, may pass through the open upstream mandrel grip 106. After a specified number of billets has passed through the open upstream mandrel grip 106, the gripper 106 may close and thereby return to gripping the mandrel bar 100, and the billets may be advanced to the downstream gripping element 108. The downstream gripping element 108 may remain closed, thereby gripping the mandrel bar 100, or the downstream mandrel grip 108 may open after the upstream mandrel grip 106 re-grips the mandrel bar 100. Although two mandrel grips 106, 108 are shown in the extrusion press system 10, it will be understood that any suitable number of mandrel grips may be provided.

The fluid clamps 102, 104 comprise a mandrel bar fluid delivery system 101 designed to supply cooling fluid along the interior of the mandrel bar 100 to the mandrel bar tip during the extrusion process. The fluid clamps 102, 104 also receive cooling fluid from the mandrel bar 100 that has returned from the mandrel bar tip. Any suitable cooling fluid may be used, including water, various mineral oils, brines, synthetic oils, any other suitable cooling fluid, including gaseous fluids, or any combination thereof. The fluid clamps 102, 104 may be controlled by the PLC system to continuously supply process cooling fluid to the mandrel bar during the extrusion process while allowing a plurality of billets to be continuously feed along and about the mandrel bar 100. The fluid clamps 102, 104 operate such that there is no or substantially no interruption to the supply of process cooling fluid to the mandrel bar tip during the extrusion process. Similar to the operation of the mandrel grips 106, 108 discussed above, when the fluid clamps 102, 104 are clamped to or engaged with the mandrel bar 100, the fluid clamps 102, 104 prevent billets from being transported along the mandrel bar 100 through the fluid clamps.

The fluid clamps 102, 104 operate such that at any given time during the extrusion at least one of the fluid clamps is clamped to or engaged with the mandrel bar 100 and thereby delivers cooling fluid into the mandrel bar 100 for delivery to the mandrel bar tip. When a billet passes through one of the fluid clamps 102, 104, the respective fluid clamp discontinues delivering (and receiving) cooling fluid and releases or disengages the mandrel bar 100 to allow the billet to pass therethrough before re-clamping the mandrel bar 100 and continuing to deliver (and receive) cooling fluid. While one of the fluid clamps 102, 104 is unclamped or disengaged from the mandrel bar 100, the other fluid clamp continues to deliver cooling fluid to the mandrel bar.

For example, the upstream fluid clamp 102 may release the mandrel bar 100 while the downstream fluid clamp 104 is clamped to the mandrel bar 100. At any given time, at least one of the fluid clamps 102, 104 is preferably clamped to the mandrel bar 100 to continuously deliver cooling fluid. One or more billets queued or indexed near the upstream fluid clamp 102, or being transported along the mandrel bar 100, may pass through the open upstream fluid clamp 102. After a specified number of billets has passed through the open upstream fluid clamp 102, the fluid clamp 102 may close and thereby return to clamping the mandrel bar 100 and delivering cooling fluid, and the billets may be advanced to the downstream fluid clamp 104. The downstream fluid clamp 104 may remain closed, thereby clamping the mandrel bar 100, or the downstream fluid clamp 104 may open after the upstream fluid clamp 102 re-clamps to the mandrel bar 100. Although two fluid clamps 102, 104 are shown in the extrusion press system 10, it will be understood that any suitable number of fluid clamps may be provided.

The billet delivery system ensures that a continuous supply of billets is present for the extrusion process. When additional billets are needed, the PLC system will cycle the proper mandrel bar grips 106, 108, fluid clamps 102, 104, and billet delivery rollers to ensure that the billet supply is continuous. The section of the mandrel carriage 280 located between the mandrel grip 106 and the entry platen 120 may continuously index to minimize the gap between billets fed into the ram platen sections 141 of the platen structure 290. For example, at this location of the mandrel carriage 280, the track assembly may continuously cycle the track to feed billets into the platen structure 290.

The mandrel bar 100 extends along substantially the length of the extrusion press system 200 and is positioned to place the mandrel bar tip within the rotating die 160. The adjustment to properly position the mandrel bar tip within the rotating die 160 is accomplished by moving the mandrel carriage section 280, thus moving the mandrel bar 100. The adjustments to the mandrel bar 100 and the mandrel carriage section 280 may be towards or away from the die 160. The mandrel bar 100 and the mandrel carriage section 280 preferably cannot be adjusted while the extrusion press system 200 is in operation, although it will be understood that in certain embodiments the mandrel bar 100 and/or mandrel carriage section 280 may be adjusted during operation.

As discussed above, the extrusion press system 200 includes a platen structure section 290 having an entry platen 120 and a rear die platen 122, press-ram platens 130 and 140, a centering platen 152, and a rotating die 160 pressed against the rear die platen 122. Near the entry platen 120 is the press-ram assembly 141 that includes a first press-ram platen 130 and a second press-ram platen 140. The first and second press-ram platens 130, 140 feed billets into the centering platen 152, which grips the billets and prevents the billets from rotating prior to entering the rotating die 160, which presses against the rear die platen 122. The entry platen 120 and the rear die platen 122 are coupled by a series of tie rods 124 that act as guides for the press-ram platens 130, 140 and the centering platen 152, each of which includes bearings 126a, 126b, 126c that move along the tie rods 124. The rear die platen 122 and the entry platen 120 have mounting locations 127 through which the tie rods 124 are fixed. The entry platen 120, rear die platen 122, and tie rod structure 124 are supported by the frame 190. The frame 190 also holds the spindle 172 and motor 170. At the exit of the rotating die 160 is a quench tube 180 for rapidly cooling the extruded tubing.

The press-ram platens 130, 140 operate by gripping the billets and providing a substantially constant pushing force in the direction of the extrusion die stack 160. At any given time at least one of the press-ram platens 130, 140 grips a billet and advances the billet along the mandrel bar 100 to provide the constant pushing force. The press-ram platens 130, 140 form the final part of the billet delivery subsystem 220 before the billet enters the centering insert 150 of centering platen 152 and the rotating die 160 of the extrusion subsystem 240. Similar to the billet feed track section before the entry platen 120, the section prior to the press-ram platens 130, 140 preferably continuously indexes the billets to minimize any gaps between a billet that is gripped the press-ram platens 130, 140 and the next billet.

As discussed above, the press-rams 130, 140 continuously push billets into the rotating die 160. The press-rams 130, 140 alternate gripping and advancing billets towards and into the rotating die 160 and then ungripping the advanced billets and retracting for the next gripping/advancing cycle. There is preferably an overlap between the time when one press-ram stops pushing and the other press-ram is about to start pushing so that there is always uniform pressure on the rotating die 160. The press-rams 130, 140 advance and retract via press-ram cylinders coupled to the respective press-ram. As shown there are two press-ram cylinders 132, 142 per press-ram. A first set of press-ram cylinders 132 is located to the left and right of the entry platen 120 (although the right-side press-ram cylinder is hidden from view by the left-side press-ram cylinder). The first set of press-ram cylinders 132 couples with the first press-ram platen 130 and is configured to move the first press-ram 130 along the tie rods 124 as the first press-ram 130 advances billets and then retracts for subsequent billets. A second set of press-ram cylinders 142 is located on the top and bottom of the entry platen 120. The second set of press-ram cylinders 142 couples with the second press-ram platen 140 and is configured to move the second press-ram 140 along the tie rods 124 as the second press-ram 140 advances billets and then retracts for subsequent billets. Although two press-ram cylinders are shown for each of the first and second press-ram platens 130, 140, it will be understood that any suitable number of press-ram cylinders may be provided. In certain embodiments, press-ram cylinders may be coupled to both press-rams 130, 140.

The centering platen 152 receives billets advanced by the press-rams 130, 140 and functions to hold the billets during the extrusion process prior to entry of the billets into the rotating die 160. When the centering platen 152 is positioned in place for the extrusion process, the centering platen 152 substantially becomes part of the extrusion die 160. That is, a centering insert 150 of the centering platen 152 substantially abuts the rotating die 160. The centering platen 152 itself, however, and the components therein including the centering insert 150, do not rotate with the rotating die 160. The centering platen 152 prevents billets that are no longer held by the second press-ram 140 from rotating while the die 160 rotates by gripping the billets and thereby preventing the billets from rotating prior to entry of the billets into the rotating die 160.

As discussed above, the extrusion press system 200 includes positive stops 154, 156. The positive stops 154, 156 are coupled to a first support structure 162 and extend towards a second support structure, the centering platen 152, with a gap between contact surfaces of the respective components that amounts to a travel distance. During operation, the first support structure 162 is stationary and the second support structure 152 moves relative to the first support structure 162. For example, one or more piston/cylinder drive units (similar to the press-ram cylinders discussed above with respect to the press-ram operation) may be coupled to the support structure 152 to advance and optionally retract the structure along the tie rods 124. In certain embodiments, the second support structure 152 moves in a direction towards the first support structure 162 (along arrow B) and a direction away from the first support structure (opposite arrow B). The positive stops 154, 156 therefore define a travel distance between the respective support structures 162, 152. Although the positive stops 154, 156 are shown as coupled to and extending from the first support structure 162 towards the second support structure 152, other configurations may be used. For example, in some embodiments, a positive stop may be coupled to the second support structure 152 and extend towards the first support structure 162, with a gap between respective contact surfaces of the positive stop and first support structure 162. Any suitable arrangement for preventing motion of one (or more) of the support structures may be used.

The rotating die 160 may have a unibody design, or may include a plurality of die plates stacked together. In certain embodiments, the die includes a base plate, a final plate, a second intermediate plate, a first intermediate plate, an entry plate, and a steel end holder, and the die plates are bolted together or otherwise coupled to form the die 160. In some embodiments, additional plates may be added to form the rotating die. The rotating die 160 is bolted to or otherwise coupled with the spindle 172, which is operated by the motor 170. A gear box is bolted to the rear die platen 122 and contains the spindle 172 as well as the drive chain, motor drive gear, gear oil reservoir, and gear oil heat exchanger, which are not shown in FIG. 5 to avoid overcomplicating the figure. In certain embodiments, the spindle motor 170 and the spindle/die gear tooth ratio is 2.5:1, although it will be understood that any suitable gear ratio may be used for the rotation of the rotating die 160.

At the extrusion end of the extrusion press system 200 is a quench box 185 bolted or otherwise coupled to the exit side of the gear box on the rear die platen 122. In certain embodiments, within the quench box 185 is a quench tube 180 for rapidly quenching or cooling the extruded material as it exits the rotating die 160. Water may be used as the quenching or cooling fluid, and the water may contact the extruded material sometime after the exit of the extruded material from the rotating die 160. For example, in certain embodiments, the extruded material is quenched with cooling fluid within approximately 1 inch, or less, of exiting the rotating die 160. Any suitable cooling fluid may be used for quenching an extruded material, including water, various mineral oils, brines, synthetic oils, any other suitable cooling fluid, including gaseous fluids, or any combination thereof. The quench tube 180 may be formed of one or more tubes having a channel therein for delivering the cooling fluid to the extruded material. In certain embodiments, the quench tube 180 further includes an end cap or other structure through which the cooling fluid is delivered to the extruded material. Any suitable quench tube may be used the extrusion press system of this disclosure.

In certain embodiments, nitrogen gas, or another suitable inert gas, is delivered to the interior of an extruded material as the material exits the rotating die. For example, nitrogen gas may be delivered to the interior of extruded tubing using a cap placed on the leading end of the extruded tubing as it exits the rotating die. Injecting gaseous or liquid nitrogen into the rotating die assembly, or the interior of the extruded material itself, can minimize oxide formation by displacing the oxygen-laden air.

The foregoing is merely illustrative of the principles of the disclosure, and the systems, devices, and methods can be practiced by other than the described embodiments, which are presented for purposes of illustration and not of limitation. It is to be understood that the systems, devices, and methods disclosed herein, while shown for use in extrusion press systems, may be applied to systems, devices, and methods to be used in other manufacturing procedures including, but not limited to, cast-and-roll, up-casting, other extrusion, and other manufacturing procedures.

Variations and modifications will occur to those of skill in the art after reviewing this disclosure. The disclosed features may be implemented, in any combination and subcombination (including multiple dependent combinations and subcombinations), with one or more other features described herein. The various features described or illustrated above, including any components thereof, may be combined or integrated in other systems. Moreover, certain features may be omitted or not implemented.

Examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and could be made without departing from the scope of the information disclosed herein. As used herein, the term “about” refers to a number that varies by up to 5%, or in other embodiments up to 10%, and in other embodiments up to 25%, from the number being referred to. The allowable variation encompassed by the term “about” will depend upon the particular system, and can be readily appreciated by one of ordinary skill in the art. Whenever a range is recited within this disclosure, every whole number integer within the range is also contemplated as an embodiment of the disclosure. All references cited herein are incorporated by reference in their entirety and made part of this application.

Claims

1. An extrusion press system comprising:

an extrusion die supported by a first support structure;

a centering insert supported by a second support structure, wherein the centering insert guides a material to be extruded into the extrusion die; and

a positive stop coupled to the first support structure and extending towards the second support structure, wherein the positive stop defines a travel distance between the first support structure and the second support structure.

2. The extrusion press system of claim 1, wherein the extrusion die rotates within the first support structure.

3. The extrusion press system of claim 2, wherein the centering insert is positioned against the extrusion die and does not rotate.

4. The extrusion press system of claim 3, wherein the centering insert comprises gripping features that frictionally engage the material to be extruded and thereby prevent the material from rotating while engaged and as the material enters the rotating extrusion die.

5. The extrusion press system of claim 1, wherein the first support structure is stationary, and wherein the second support structure is configured to move relative to the first support structure.

6. The extrusion press system of claim 5, wherein movement of the second support structure towards the first support structure is limited by the positive stop to the travel distance.

7. The extrusion press system of claim 5, wherein the centering insert is a consumable part that is partially consumed when the second support structure moves towards the first support structure a distance of the travel distance.

8. The extrusion press system of claim 1, wherein the positive stop is configured to adjust the travel distance.

9. The extrusion press system of claim 8, wherein the positive stop comprises an adjustable portion that rotates about a threaded shaft for increasing or decreasing the travel distance.

10. The extrusion press system of claim 8, wherein the positive stop comprises an adjustable portion that slides along a shaft for increasing or decreasing the travel distance.

11. The extrusion press system of claim 8, wherein the positive stop comprises a recess configured to mate with a plurality of end portions, each respective end portion having a respective thickness for increasing or decreasing the travel distance.

12. The extrusion press system of claim 10, wherein the positive stop further comprises a through-hole into which a locking pin is positioned.

13. The extrusion press system of claim 1, further comprising a second positive stop.

14. The extrusion press system of claim 1, wherein the travel distance is between about zero inches and about 100/1000 inch.

15. The extrusion press system of claim 14, wherein the travel distance is about 20/1000 inch.

16. A method for extruding a material comprising:

positioning a centering insert in a first position against an extrusion die;

exerting a force on the centering insert to maintain a desired pressure of the centering insert against the extrusion die, wherein the force moves the centering insert from the first position to a second position; and

preventing further movement of the centering insert at the second position.

17. The method of claim 16, wherein upon preventing further movement, a pressure of the centering insert against the extrusion die decreases relative to the desired pressure.

18. The method of claim 16, wherein the force continues to be exerted while movement of the centering insert is prevented at the second position.

19. The method of claim 16, wherein a distance between the first position and the second position defines a travel distance.

20. The method of claim 19, further comprising adjusting the travel distance.

21. The method of claim 16, wherein the extrusion die rotates, and wherein the centering insert does not rotate.

22-36. (canceled)