Patent Publication Number: US-11045852-B2

Title: Extrusion press container and mantle for same

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to extrusion and in particular, to an extrusion press container and a mantle for same. 
     BACKGROUND OF THE INVENTION 
     Metal extrusion presses are well known in the art, and are used for forming extruded metal products having cross-sectional shapes that generally conform to the shape of the extrusion dies used. A typical metal extrusion press comprises a generally cylindrical container having an outer mantle and an inner tubular liner. The container serves as a temperature controlled enclosure for a billet during extrusion. An extrusion ram is positioned adjacent one end of the container. The end of the extrusion ram abuts a dummy block, which in turn abuts the billet allowing the billet to be advanced through the container. An extrusion die is positioned adjacent the opposite end of the container. 
     During operation, once the billet is heated to a desired extrusion temperature (typically 800-900° F. for aluminum), it is delivered to the extrusion press. The extrusion ram is then activated to abut the dummy block thereby advancing the billet into the container and towards the extrusion die. Under the pressure exerted by the advancing extrusion ram and dummy block, the billet is extruded through the profile provided in the extrusion die until all or most of the billet material is pushed out of the container, resulting in the extruded product. 
     In order to attain cost-saving efficiency and productivity in metal extrusion technologies, it is important to achieve thermal alignment of the extrusion press. Thermal alignment is generally defined as the control and maintenance of optimal running temperature of the various extrusion press components. Achieving thermal alignment during production of extruded product ensures that the flow of the extrudable material is uniform, and enables the extrusion press operator to press at a higher speed with less waste. 
     As will be appreciated, optimal billet temperature can only be maintained if the container can immediately correct any change in the liner temperature during the extrusion process, when and where it occurs. Often all that is required is the addition of relatively small amounts of heat to areas that are deficient. 
     A number of factors must be considered when assessing the thermal alignment of an extrusion press. For example, the whole of the billet of extrudable material must be at the optimum operating temperature in order to assure uniform flow rates over the cross-sectional area of the billet. The temperature of the liner in the container must also serve to maintain, and not interfere with, the temperature profile of the billet passing therethrough. 
     Achieving thermal alignment is generally a challenge to an extrusion press operator. During extrusion, the top of the container usually becomes hotter than the bottom. Although conduction is the principal method of heat transfer within the container, radiant heat lost from the bottom surface of the container rises inside the container housing, leading to an increase in temperature at the top. As the front and rear ends of the container are generally exposed, they will lose more heat than the center section of the container. This may result in the center section of the container being hotter than the ends. As well, the temperature at the extrusion die end of the container tends to be slightly higher compared to the ram end, as the billet heats it for a longer period of time. These temperature variations in the container affect the temperature profile of the liner contained therein, which in turn affects the temperature of the billet of extrudable material. The temperature profile of the extrusion die generally conforms to the temperature profile of the liner, and the temperature of the extrusion die affects the flow rate of extrudable material therethrough. Although the average flow rate of extrudable material through the extrusion die is governed by the speed of the ram, flow rates from hotter sections of the billet will be faster compared to cooler sections of the billet. The run-out variance across the cross-sectional profile of a billet can be as great as 1% for every 5° C. difference in temperature. This can adversely affect the shape of the profile of the extruded product. Control of the temperature profiles of the liner and of the container is therefore of great importance to the efficient operation of the extrusion process. 
     One approach to achieving such temperature profile control of the liner and the container involves introducing cooling to the container. Cooling in extrusion press containers has been previously described. For example, U.S. Pat. No. 5,678,442 to Ohba et al. describes an extruder having a cylindrical container into which a billet is loaded; a two-piece seal block disposed on an end surface of the container at an extruding stem side; a vacuum deaerating hole formed in the seal block; and a fixed dummy block, having an internal cooling function, fixed to an end of the extruding stem, wherein the seal block is allowed to be opened and closed in a direction perpendicular to the axial direction of the container and the seal block comes in close contact with an outer surface of the extruding stem and the end surface of the container when the seal block is closed. 
     Japanese Patent Application No. 2010115664 to Ube Machinery Corporation Ltd. describes a container device of an extruding press, the container device being provided with a heating means on an outer peripheral surface and an end face, and divided into an upper part and a lower part in the radial direction and in a plurality of places in the length direction, the temperature of which is made freely controllable respectively in each divided zone. The container device also has an internal cooling means, for enabling the temperature to be freely controlled respectively independently in the upper and lower parts into which the container is divided. 
     Chinese Patent Document No. 202185474 to Wei describes a cooling and controlling device for extrusion cylinders, comprising an extrusion cylinder sleeve, an extrusion cylinder middle lining and an extrusion cylinder inner lining. The extrusion cylinder middle lining is provided with a spiral cooling groove. The spiral cooling groove is divided into four areas which are respectively in communication with a compressed air inlet and a compressed air outlet. The compressed air inlet is in communication with a compressed air source through an air inlet pipe joint, and the compressed air outlet is in communication with a silencing device through a vent pipe joint. A compressed air control system is connected between the compressed air source and the air inlet pipe joint. 
     U.S. Pat. No. 9,815,102 to Robbins describes a container for use in a metal extrusion press comprising a mantle having an elongate body comprising an axial bore, an elongate liner accommodated within the axial bore, the liner comprising a longitudinally extending passage through which a billet is advanced, and a fluid channel in thermal communication with the mantle through which a fluid for cooling the container flows. 
     Improvements are generally desired. It is therefore an object at least to provide a novel extrusion press container and a mantle for same. 
     SUMMARY OF THE INVENTION 
     It should be appreciated that this summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to be used to limit the scope of the claimed subject matter. 
     In one aspect, there is provided a container for use in a metal extrusion press, the container having a longitudinal axis, the longitudinal axis being oriented generally horizontally and dividing the container into an upper portion and a lower portion when the container is in the use position, the container comprising: a mantle comprising an elongate body having an outer surface and an axial bore therein; an elongate liner accommodated within the axial bore, the liner comprising a longitudinally extending passage therein through which a billet is advanced; a first fluid channel adjacent an outer surface of the mantle, the first fluid channel being configured to direct a first fluid therethrough for cooling a first end of the container; and a second fluid channel adjacent an outer surface of the mantle, the second fluid channel being configured to direct a second fluid therethrough for cooling a second end of the container. 
     The second fluid may be water. 
     The first fluid and the second fluid may be different fluids. The first fluid may be air, and the second fluid may be water. 
     The mantle may comprise a plurality of longitudinal bores, each of the bores accommodating a respective heating element. The heating elements may be arranged circumferentially about the central axial bore of the mantle. The container may further comprise at least one longitudinal temperature sensor positioned in the mantle adjacent at least one of the first fluid channel and the second fluid channel. The at least one longitudinal temperature sensor may be positioned between the longitudinal bores and said at least one of the first fluid channel and the second fluid channel. 
     The first fluid channel may comprise a groove disposed on the outer surface of the mantle. The groove may be a serpentine groove. The first fluid channel may further comprise a cover plate covering the groove. 
     The second fluid channel may comprise tubing disposed on the outer surface of the mantle. The tubing may be disposed in a groove formed on the outer surface of the mantle. The groove may be a serpentine groove. 
     The container may further comprise a manifold configured for one or more of: delivering fluid to at least one of the first fluid channel and the second fluid channel; and removing fluid from at least one of the first fluid channel and the second fluid channel. 
     The container may further comprise a longitudinal temperature sensor positioned in the mantle adjacent at least one of the first fluid channel and the second fluid channel. 
     In another aspect, there is provided a mantle for a container for use in a metal extrusion press, the mantle comprising: an elongate body having an outer surface and an axial bore therein, the axial bore configured to accommodate an elongate liner comprising a longitudinally extending passage therein through which a billet is advanced; a first fluid channel adjacent an outer surface of the mantle, the first fluid channel being configured to direct a first fluid therethrough for cooling a first end of the container; and a second fluid channel adjacent an outer surface of the mantle, the second fluid channel being configured to direct a second fluid therethrough for cooling a second end of the container. 
     In still another aspect, there is provided a container for use in a metal extrusion press, the container comprising: a mantle comprising an elongate body having an outer surface and a first axial bore therein; an elongate subliner accommodated within the first axial bore, the subliner having a second axial bore therein; an elongate liner accommodated within the second axial bore, the liner comprising a longitudinally extending passage therein through which a billet is advanced; a first fluid channel adjacent an outer surface of the mantle, the first fluid channel being configured to direct a first fluid therethrough for cooling a first end of the container; and a second fluid channel adjacent an outer surface of the mantle, the second fluid channel being configured to direct a second fluid therethrough for cooling a second end of the container. 
     The subliner may comprise a plurality of longitudinal bores, each of the bores accommodating a respective heating element. 
     The container may further comprise at least one longitudinal temperature sensor positioned in the mantle adjacent at least one of the first fluid channel and the second fluid channel. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments will now be described more fully with reference to the accompanying drawings in which: 
         FIG. 1  is a schematic perspective view of a metal extrusion press; 
         FIG. 2  is a perspective view of a container forming part of the metal extrusion press of  FIG. 1 ; 
         FIG. 3  is a perspective view of the container of  FIG. 2 , in a use configuration; 
         FIG. 4  is a top view of the container of  FIG. 2 ; 
         FIG. 5  is an end view of the container of  FIG. 2   
         FIG. 6  is a side view of the container of  FIG. 2 ; 
         FIG. 7  is a sectional view of the container of  FIG. 5 , taken along the indicated section line; 
         FIG. 8  is a schematic view of the container of  FIG. 2 ; 
         FIG. 9  is a perspective view of a heating element for use with the container of  FIG. 2 ; 
         FIG. 10  is an end view of another embodiment of a container for use with the metal extrusion press of  FIG. 1 ; and 
         FIG. 11  is a sectional view of the container of  FIG. 10 , taken along the indicated section line. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The foregoing summary, as well as the following detailed description of certain examples will be better understood when read in conjunction with the appended drawings. As used herein, an element or feature introduced in the singular and preceded by the word “a” or “an” should be understood as not necessarily excluding the plural of the elements or features. Further, references to “one example” or “one embodiment” are not intended to be interpreted as excluding the existence of additional examples or embodiments that also incorporate the described elements or features. Moreover, unless explicitly stated to the contrary, examples or embodiments “comprising” or “having” or “including” an element or feature or a plurality of elements or features having a particular property may include additional elements or features not having that property. Also, it will be appreciated that the terms “comprises”, “has”, “includes” means “including by not limited to” and the terms “comprising”, “having” and “including” have equivalent meanings. 
     As used herein, the term “and/or” can include any and all combinations of one or more of the associated listed elements or features. 
     It will be understood that when an element or feature is referred to as being “on”, “attached” to, “connected” to, “coupled” with, “contacting”, etc. another element or feature, that element or feature can be directly on, attached to, connected to, coupled with or contacting the other element or feature or intervening elements may also be present. In contrast, when an element or feature is referred to as being, for example, “directly on”, “directly attached” to, “directly connected” to, “directly coupled” with or “directly contacting” another element of feature, there are no intervening elements or features present. 
     It will be understood that spatially relative terms, such as “under”, “below”, “lower”, “over”, “above”, “upper”, “front”, “back” and the like, may be used herein for ease of description to describe the relationship of an element or feature to another element or feature as illustrated in the figures. The spatially relative terms can however, encompass different orientations in use or operation in addition to the orientation depicted in the figures. 
       FIG. 1  is a simplified illustration of an extrusion press for use in metal extrusion. The extrusion press comprises a container  20  having an outer mantle  22  that surrounds an inner tubular liner  24 . The container  20  serves as a temperature controlled enclosure for a billet  26  during extrusion of the billet. An extrusion ram  28  is positioned adjacent one end of the container  20 . The end of the extrusion ram  28  abuts a dummy block  30 , which in turn abuts the billet  26  allowing the billet to be advanced through the container  20 . An extrusion die  32  is positioned adjacent a die end  34  of the container  20 . 
     During operation, once the billet  26  is heated to a desired extrusion temperature (typically 800-900° F. for aluminum), it is delivered to the extrusion press. The extrusion ram  28  is then actuated to abut the dummy block  30 , thereby to advance the billet  26  into the container and towards the extrusion die  32 . Under the pressure exerted by the advancing extrusion ram  28  and dummy block  30 , the billet  26  is extruded through the profile provided in the extrusion die  32  until all or most of the billet material is pushed out of the container  20 , resulting in the extruded product  36 . 
     The container  20  may be better seen in  FIGS. 2 to 8 . The container  20  is configured at the die end  34 , and along the side sections thereof, in a manner known in the art to facilitate coupling of the container  20  to the extrusion press. The mantle  22  has a generally cylindrical shape and comprises an axial bore accommodating the liner  24 . In this embodiment, the mantle  22  and the liner  24  are shrunk-fit together. 
     The mantle  22  comprises a plurality of longitudinal bores  38  extending from a ram end  40  of the mantle  22  to the die end  34  of the mantle  22 , and surrounding the liner  24 . Each longitudinal bore  38  is shaped to accommodate an elongate heating element, further described below, that can be energized to provide thermal energy to the mantle  22  in the vicinity of the liner  24  during use. The number of longitudinal bores  38  needed depends on the size of the container  20  and on the voltage used to energize the elongate heating elements. In this embodiment, the mantle  22  comprises eighteen (18) longitudinal bores  38 . The container  20  has an end cover plate  42  installed on its die end  34  that covers the ends of the longitudinal bores  38 . 
     The mantle  22  also comprises a plurality of bores  44  and  46  adjacent the liner  24  and extending partially into the length of the mantle  22 . In this embodiment, the mantle  22  comprises two (2) bores  44  extending from the die end  34  approximately four (4) inches into the mantle  22 , and two (2) bores  46  extending from the ram end  40  approximately four (4) inches into the mantle  22 . Each bore  44  and  46  is shaped to accommodate a temperature sensor (not shown). The bores  44  and  46  are positioned in a manner so as to avoid intersecting any of the longitudinal bores  38  configured for accommodating the heating elements. In this embodiment, one (1) of the bores  44  is positioned above the liner  24  while the other bore  44  is positioned below the liner  24 , and one (1) of the bores  46  is positioned above the liner  24  while the other bore  46  is positioned below the liner  24 . The mantle  22  also comprises a longitudinal bore  48  in an upper portion of the mantle, radially outward of the nearest longitudinal bore  38 . The bore  48  extends from the ram end  40  approximately sixteen (16) inches into the mantle  22 , or approximately two thirds (⅔) the length of the mantle  22 . The bore  48  is sized to accommodate two (2) temperature sensors (not shown), each of which is positioned in proximity to a respective heat sink, described below. 
     The liner  24  comprises a billet receiving passage  50  that extends longitudinally therethrough and, in the embodiment shown, the passage  50  has a generally circular cross-sectional profile. 
     The container  20  also comprises two (2) heat sinks that are configured for cooling the container  20 . In this embodiment, the heat sinks comprise a first fluid channel  52  adjacent the ram end  40  of the container  20 , and a second fluid channel  54  adjacent the die end  34  of the container  20 . The first fluid channel  52  and second fluid channel  54  are separate, and are not in fluid communication with each other. 
     The first fluid channel  52  comprises a first circumferential groove  56  formed in an upper portion of the outer surface of the mantle  22  adjacent the ram end  40 , and a cover plate  58  sized to cover the first circumferential groove  56 . The first circumferential groove  56  has a first end  60  and a second end  62 , and defines a serpentine path between the first and second ends  60  and  62 . The first circumferential groove  56  is formed such that at least a majority of its length is formed in the upper half of the mantle  22 , and in the embodiment shown the entirety of the first circumferential groove  56  is formed in the upper half of the mantle  22 . Additionally, the first circumferential groove  56  is formed such that at least a majority of its length is formed in the half of the mantle  22  at the ram end  40 , and in the embodiment shown the entirety of the first circumferential groove  56  is formed in the half of the mantle  22  at the ram end  40 . When the cover plate  58  is installed so as to cover the first circumferential groove  56 , the first fluid channel  52  provides a generally enclosed, continuous channel through which a first fluid flows to cool the container  20 . 
     The first fluid channel  52  is in fluid communication with a supply  64  of pressurized first fluid via a first longitudinal fluid manifold  66  mounted to a first side of the mantle  22 . The manifold  66  comprises a first fluid input port  68  that is in fluid communication with the first end  60  of the first circumferential groove  56 , and that is also in fluid communication with the supply  64  of pressurized first fluid via a supply line  72 . The first fluid is a gas, and in this embodiment the first fluid is air. A first flow rate control apparatus  74  is connected to the supply  64  of pressurized first fluid and/or the supply line  72 , and is configured to allow the flow rate of first fluid entering the first fluid input port  68  to be controlled by the operator. The manifold  66  also comprises a first fluid output port  76  that is in fluid communication with the second end  62  of the first circumferential groove  56 , and which is in fluid communication with an exhaust line  78 . 
     The second fluid channel  54  comprises a second circumferential groove  82  formed in the upper portion of the outer surface of the mantle  22  adjacent the die end  34  of the container  20 , and continuous tubing  84  sized to be accommodated within the second circumferential groove  82 . In the example shown, the second circumferential groove  82  is a continuous groove that defines a serpentine path. The tubing  84  has a first end  86  and a second end  88 , and is disposed in the second circumferential groove  82  to define a serpentine path between the first and second ends  86  and  88 . Similar to the first circumferential groove  56 , the second circumferential groove  82  is configured such that at least a majority of the length of the tubing  84  is disposed in the upper half of the mantle  22 , and in the embodiment shown the entirety of the length of the tubing  84  is disposed in the upper half of the mantle  22 . Additionally, the first circumferential groove  56  is formed such that at least a majority of its length is formed in the half of the mantle  22  at the die end  34 , and in the embodiment shown the entirety of the first circumferential groove  56  is formed in the half of the mantle  22  at the die end  34 . The tubing  84  is configured to convey a second fluid therethrough to cool the container  20 . 
     The second fluid channel  54  is in fluid communication with a supply  90  of pressurized second fluid via a second longitudinal fluid manifold  92  mounted to a second side of the mantle  22 . The manifold  92  comprises a second fluid input port (not shown) that is in fluid communication with the first end  86  of the tubing  84 , and that is also in fluid communication with the supply  90  of second fluid via a supply line  94 . In this embodiment, the second fluid is water. A second flow rate control apparatus  96  is connected to the supply of second fluid and/or the supply line, and is configured to allow the flow rate of second fluid entering the manifold  92  to be controlled by the operator. The manifold  92  also comprises a second fluid output port (not shown) that is in fluid communication with the second end  88  of the continuous tubing  84 , and which is in fluid communication with a second fluid discharge  98 . In this embodiment, the second fluid discharge  98  is a drain. 
       FIG. 9  shows one of the elongate heating elements for use with the container  20 , and which is generally indicated by reference numeral  108 . Heating element  108  is a cartridge-type element. The regions of the container in greatest need of added temperature are generally the die end  34  and ram end  40 , referred to as die end zone  110   a  and ram end zone  110   b , respectively. As such, each heating element  108  may be configured with segmented heating regions. In this embodiment, and as shown in  FIG. 9 , each heating element  108  is configured with a die end heating section  112  and a ram end heating section  114 , which are separated by a central unheated section  116 . To energize and control the heating elements, lead lines  118  feed to each heating section  112 ,  114 . The lead lines connect to various bus lines (not shown), which in turn connect to a controller (not shown). The arrangement of the bus lines may take any suitable configuration, depending on the heating requirements of the container  20 . In this embodiment, the bus lines are configured to selectively allow heating of the die end zone  110   a  and ram end zone  110   b  of the container, or more preferably just portions thereof, as deemed necessary by the operator. In this embodiment, the arrangement of lead lines enables each of the heating elements  108  to be individually controllable, and also enables each of the heating sections  112 ,  114  within each heating element  108  to be individually controllable. For example, the operator may routinely identify temperature deficiencies in a lower die end zone  110   c  and a lower ram end zone  110   e . The elongate heating elements  108  in the vicinity of the lower die end zone  110   c  and the lower ram end zone  110   e  are configured to be controlled by the operator to provide added temperature when required. Similarly, the elongate heating elements  108  in the vicinity of an upper die end zone  110   d  and an upper ram end zone  110   f  are configured to be controlled by the operator to provide reduced temperature when required. It will also be appreciated that the operator can selectively heat zones so as to maintain a preselected billet temperature profile. For example, the operator may choose a billet temperature profile in which the temperature of the billet progressively increases towards the die end, but with a constant temperature profile across the cross-sectional area of the billet. This configuration is generally referred to as a “tapered” profile. Having the ability to selectively heat zones where necessary enables the operator to tailor and maintain a preselected temperature profile, ensuring desired productivity. 
     Each temperature sensor (not shown) is configured to monitor the temperature of the container during operation. The positioning of the two (2) bores  44  enables one (1) temperature sensor to be placed in the upper die end zone  110   d , and one (1) temperature sensor to be placed in the lower die end zone  110   c . Similarly, the positioning of the two (2) bores  46  enables one (1) temperature sensor to be placed in the upper ram end zone  110   f , and one (1) temperature sensor to be placed in the lower ram end zone  110   e . In this embodiment, the temperature sensors are thermocouples. The temperature sensors feed into the controller, providing the operator with temperature data from which subsequent temperature adjustments can be made. As will be appreciated, the positioning of temperature sensors located in bores  44  and  46  both above and below the liner  24  advantageously allows the vertical temperature profile across the liner  24  to be measured, and moreover allows any vertical temperature difference that arises during extrusion to be monitored by the operator. 
     Additionally, the positioning of the bore  48  enables one (1) temperature sensor to be placed in the upper ram end zone  110   f  in proximity to the first fluid channel  52 , and one (1) temperature sensor to be placed in the upper die end zone  110   d  in proximity to the second fluid channel  54 . In this embodiment, these temperature sensors are also thermocouples that feed into the controller, providing the operator with temperature data from which subsequent temperature adjustments can be made. As will be appreciated, the positioning of temperature sensors in bore  48  in proximity to each of the first fluid channel  52  and the second fluid channel  54  allows the cooling provided by each of the first and second fluid channels  52  and  54  to be directly monitored. Moreover, the proximity of the temperature sensors in bore  48  to each of the first and second fluid channels  52  and  54  allows temperature changes resulting from adjustment to the flow rate of either the first fluid or the second fluid to be observed quickly after such flow rate adjustments are made. 
     During operation, temperature data output from the temperature sensors is monitored by the operator. The position of the second fluid channel  54  advantageously allows any temperature increase within the upper die end zone  110   d  to be reduced or eliminated by increasing the second fluid flow rate therethrough. As will be understood, second fluid provided by the second fluid supply line enters the first end  86  of the tubing  84  via the second input port of the fluid manifold  92 . As the second fluid travels along the length of the tubing to the second end  88 , heat is transferred from the mantle  22  to the flowing second fluid. The second fluid exits from the second fluid channel  54  via the output port and enters the discharge  98 . As will be appreciated, the transfer of heat from the mantle  22  to the flowing second fluid results in a temperature reduction within the upper die end zone  110   d  of the container  20 . 
     The position of the elongate heating elements also advantageously allows any temperature increase within the upper die end zone  110   d  to be reduced or eliminated by reducing the thermal energy supplied by heating elements  108  positioned above the liner  24 . Thus, as each of the heating elements are individually controllable, and as the flow rate of second fluid through the second fluid channel  54  is also controllable, the thermal profile across the liner  24  and within the container  20  adjacent the die end  34  can be accurately controlled. As will be understood, one or both of control of the second fluid flow rate through the second fluid channel  54 , and control of the thermal energy supplied by the heating elements, may be used to control the thermal profile across the liner  24  and within the container  20  adjacent the die end  34 . 
     Similarly, the position of the first fluid channel  52  advantageously allows any temperature increase within the upper ram end zone  110   f  to be reduced or eliminated by increasing the first fluid flow rate therethrough. As will be understood, first fluid provided by the pressurized first fluid supply line enters the first end  60  of the first circumferential groove  56  via the first input port  68  of the fluid manifold  66 . As the fluid travels along the length of the first circumferential groove  56  to the second end  62 , heat is transferred from the mantle  22  to the flowing fluid. The fluid exits from the first fluid channel  52  via the output port  76  and enters the exhaust line  78 . As will be appreciated, the transfer of heat from the mantle  22  to the flowing first fluid results in a temperature reduction within the upper ram end zone  110   f  of the container  20 . 
     The position of the elongate heating elements also advantageously allows any temperature increase within the upper ram end zone  110   f  to be reduced or eliminated by reducing the thermal energy supplied by heating elements  108  positioned above the liner  24 . Thus, as each of the heating elements are individually controllable, and as the flow rate of first fluid through the first fluid channel  52  is also controllable, the thermal profile across the liner  24  and within the container  20  adjacent the ram end  40  can be accurately controlled. As will be understood, one or both of control of the first fluid flow rate through the first fluid channel  52 , and control of the thermal energy supplied by the heating elements, may be used to control the thermal profile across the liner  24  and within the container  20  adjacent the ram end  40 . 
     As will be appreciated, the use of two (2) separate heat sinks, namely the first fluid channel  52  and the second fluid channel  54 , advantageously allows the temperature profile at the ram end of the container  20  to be controlled separately from the temperature profile at the ram end of the container  20 . As will be understood, this provides better control of the temperature profile within the container as a whole, as compared to conventional containers having only a single heat sink. 
     As will be appreciated, the use of water as the second fluid advantageously enables heat to be removed more quickly from the upper die end zone  110   d , as compared to the rate of heat removal from the upper ram end zone  110   f  where air is used as the first fluid. As will be understood, the thermal conductivity and isochoric specific heat (c V ) of water at 20° C. is 0.6 (W/m·K) and 4.15 (kJ/kg·K), respectively, while the thermal conductivity and isochoric specific heat (c V ) of air at 20° C. is 0.026 (W/m·K) and 0.7178 (kJ/kg·K), respectively. As a result, any temperature change observed in the die end zone  110   a  during extrusion can be more quickly controlled through adjustment of the second fluid flow rate, as compared to conventional containers. 
     In other embodiments, the container may be differently configured. For example,  FIGS. 10 and 11  show another embodiment of a container for use with the extrusion press of  FIG. 1 , and which is generally indicated by reference numeral  220 . Container  220  has an outer mantle  222  that surrounds a subliner  223 , which in turn surrounds the inner tubular liner  24 . 
     Similar to container  20  described above and with reference to  FIGS. 2 to 8 , the container  220  is configured at its die end  234 , and along the side sections thereof, in a manner known in the art to facilitate coupling of the container  220  to the extrusion press. The mantle  222  has a generally cylindrical shape and comprises an axial bore accommodating the subliner  223 . The subliner  223 , in turn, comprises an axial bore, for accommodating the liner  24 . In this embodiment, the mantle  222 , the subliner  223  and the liner  24  are shrunk-fit together. 
     The subliner  223  comprises a plurality of longitudinal bores  238  extending from a ram end  240  of the subliner  223  to the die end  34  of the subliner  223 , and surrounding the liner  24 . Each longitudinal bore  238  is shaped to accommodate an elongate heating element  108 , which can be energized to provide thermal energy to the subliner  223  in the vicinity of the liner  24  during use. 
     The subliner  223  also comprises a plurality of bores  244  and  246  adjacent the liner  24  and extending partially into the length of the subliner  223 . In this embodiment, the subliner  223  comprises two (2) bores  244  extending from the die end  234  approximately four (4) inches into the subliner  223 , and two (2) bores  246  extending from the ram end  240  approximately four (4) inches into the subliner  223 . Each bore  244  and  246  is shaped to accommodate a temperature sensor (not shown). The bores  244  and  246  are positioned in a manner so as to avoid intersecting any of the longitudinal bores  238  configured for accommodating the heating elements. In this embodiment, one (1) of the bores  244  is positioned above the liner  24  while the other bore  244  is positioned below the liner  24 , and one (1) of the bores  246  is positioned above the liner  24  while the other bore  246  is positioned below the liner  24 . 
     The mantle  222  comprises a longitudinal bore  248  in an upper portion of the mantle, radially outward of the nearest longitudinal bore configured for accommodating a heating element. The bore  248  extends from the ram end  40  approximately sixteen (16) inches into the mantle  222 , or approximately two thirds (⅔) the length of the mantle  222 . The bore  248  is sized to accommodate two (2) temperature sensors (not shown), each of which is positioned in proximity to a respective heat sink, described below. 
     The container  220  also comprises two (2) heat sinks that are configured for cooling the container  220 . In this embodiment, the heat sinks comprise the first fluid channel  52  adjacent the ram end  240  of the container  220 , and the second fluid channel  54  adjacent the die end  234  of the container  220 . As described above and with reference to  FIGS. 2 to 8 , the first fluid channel  52  and second fluid channel  54  are separate, and are not in fluid communication with each other. 
     The first fluid channel  52  comprises the first circumferential groove  56  formed in an upper portion of the outer surface of the mantle  222  adjacent the ram end  240 , and a cover plate  58  sized to cover the first circumferential groove  56 . The first circumferential groove  56  has the first end  60  and the second end  62 , and defines a serpentine path between the first and second ends  60  and  62 . The first circumferential groove  56  is formed such that at least a majority of its length is formed in the upper half of the mantle  222 , and in the embodiment shown the entirety of the first circumferential groove  56  is formed in the upper half of the mantle  222 . Additionally, the first circumferential groove  56  is formed such that at least a majority of its length is formed in the half of the mantle  222  at the ram end  40 , and in the embodiment shown the entirety of the first circumferential groove  56  is formed in the half of the mantle  222  at the ram end  240 . When the cover plate  58  is installed so as to cover the first circumferential groove  56 , the first fluid channel  52  provides a generally enclosed, continuous channel through which a first fluid flows to cool the container  220 . 
     The first fluid channel  52  is in fluid communication with a supply  64  of pressurized first fluid via a first longitudinal fluid manifold  66  mounted to a first side of the mantle  222 . The manifold  66  comprises the first fluid input port  68  that is in fluid communication with the first end  60  of the first circumferential groove  56 , and that is also in fluid communication with the supply  64  of pressurized first fluid via the supply line  72 . The first fluid is a gas, and in this embodiment the first fluid is air. A first flow rate control apparatus  74  is connected to the supply  64  of pressurized first fluid and/or the supply line  72 , and is configured to allow the flow rate of first fluid entering the first fluid input port  68  to be controlled by the operator. The manifold  66  also comprises a first fluid output port  76  that is in fluid communication with the second end  62  of the first circumferential groove  56 , and which is in fluid communication with the exhaust line  78 . 
     The second fluid channel  54  comprises the second circumferential groove  82  formed in the upper portion of the outer surface of the mantle  222  adjacent the die end  234  of the container  220 , and continuous tubing  84  sized to be accommodated within the second circumferential groove  82 . In the example shown, the second circumferential groove  82  is a continuous groove that defines a serpentine path. The tubing  84  has the first end  86  and the second end  88 , and is disposed in the second circumferential groove  82  to define a serpentine path between the first and second ends  86  and  88 . Similar to the first circumferential groove  56 , the second circumferential groove  82  is configured such that at least a majority of the length of the tubing  84  is disposed in the upper half of the mantle  222 , and in the embodiment shown the entirety of the length of the tubing  84  is disposed in the upper half of the mantle  222 . Additionally, the first circumferential groove  56  is formed such that at least a majority of its length is formed in the half of the mantle  222  at the die end  234 , and in the embodiment shown the entirety of the first circumferential groove  56  is formed in the half of the mantle  222  at the die end  234 . The tubing  84  is configured to convey a second fluid therethrough to cool the container  220 . 
     The second fluid channel  54  is in fluid communication with the supply  90  of pressurized second fluid via the second longitudinal fluid manifold  92  mounted to a second side of the mantle  222 . The manifold  92  comprises a second fluid input port (not shown) that is in fluid communication with the first end  86  of the tubing  84 , and that is also in fluid communication with the supply  90  of second fluid via the supply line  94 . In this embodiment, the second fluid is water. A second flow rate control apparatus  96  is connected to the supply of second fluid and/or the supply line, and is configured to allow the flow rate of second fluid entering the manifold  92  to be controlled by the operator. The manifold  92  also comprises a second fluid output port (not shown) that is in fluid communication with the second end  88  of the continuous tubing  84 , and which is in fluid communication with the second fluid discharge  98 . In this embodiment, the second fluid discharge  98  is a drain. 
     During operation, temperature data output from the temperature sensors is monitored by the operator. The position of the second fluid channel  54  advantageously allows any temperature increase within the upper die end zone  110   d  to be reduced or eliminated by increasing the second fluid flow rate therethrough. As will be understood, second fluid provided by the second fluid supply line enters the first end of the tubing  84  via the second input port of the fluid manifold  92 . As the second fluid travels along the length of the tubing to the second end  88 , heat is transferred from the mantle  222  to the flowing second fluid. The second fluid exits from the second fluid channel  54  via the output port and enters the discharge  98 . As will be appreciated, the transfer of heat from the mantle  222  to the flowing second fluid results in a temperature reduction within the upper die end zone  110   d  of the container  220 . 
     The position of the elongate heating elements also advantageously allows any temperature increase within the upper die end zone  110   d  to be reduced or eliminated by reducing the thermal energy supplied by heating elements  108  positioned above the liner  24 . Thus, as each of the heating elements are individually controllable, and as the flow rate of second fluid through the second fluid channel  54  is also controllable, the thermal profile across the liner  24  and within the container  220  adjacent the die end  234  can be accurately controlled. As will be understood, one or both of control of the second fluid flow rate through the second fluid channel  54 , and control of the thermal energy supplied by the heating elements, may be used to control the thermal profile across the liner  24  and within the container  220  adjacent the die end  234 . 
     Similarly, the position of the first fluid channel  52  advantageously allows any temperature increase within the upper ram end zone  110   f  to be reduced or eliminated by increasing the first fluid flow rate therethrough. As will be understood, first fluid provided by the pressurized first fluid supply line enters the first end  60  of the first circumferential groove  56  via the first input port  68  of the fluid manifold  66 . As the fluid travels along the length of the first circumferential groove  56  to the second end  62 , heat is transferred from the mantle  222  to the flowing fluid. The fluid exits from the first fluid channel  52  via the output port  76  and enters the exhaust line  78 . As will be appreciated, the transfer of heat from the mantle  222  to the flowing first fluid results in a temperature reduction within the upper ram end zone  110   f  of the container  220 . 
     The position of the elongate heating elements also advantageously allows any temperature increase within the upper ram end zone  110   f  to be reduced or eliminated by reducing the thermal energy supplied by heating elements  108  positioned above the liner  24 . Thus, as each of the heating elements are individually controllable, and as the flow rate of first fluid through the first fluid channel  52  is also controllable, the thermal profile across the liner  24  and within the container  220  adjacent the ram end  240  can be accurately controlled. As will be understood, one or both of control of the first fluid flow rate through the first fluid channel  52 , and control of the thermal energy supplied by the heating elements, may be used to control the thermal profile across the liner  24  and within the container  220  adjacent the ram end  240 . 
     It will be understood that the liner is not limited to the configuration described above, and in other embodiments, the liner may alternatively have other configurations. For example, the liner may alternatively comprise a billet receiving passage having a generally rectangular cross-sectional profile that may comprise any of flared ends, rounded corners, and rounded sides, as described in U.S. Pat. No. 9,975,160 issued on May 22, 2018, entitled “EXTRUSION PRESS CONTAINER AND LINER FOR SAME”, the content of which is incorporated by reference herein in its entirety. 
     In still other embodiments, the container may be differently configured. For example, in other embodiments, the first fluid channel may alternatively be configured identically to the second fluid channel, such that the first fluid channel also comprises continuous tubing accommodated within the first circumferential groove formed in the upper portion of the outer surface of the mantle adjacent the ram end of the container, with the continuous tubing being configured to convey the first fluid therethrough to cool the container, with the first fluid also being water instead of air. In such an embodiment, the first fluid channel would be in fluid communication with the supply of water via a suitable supply line, and with a water flow rate control apparatus is connected to the water supply and/or the water supply line. Thus, in such an embodiment, both the first fluid channel and the second fluid channel would be configured to convey separately adjustable circuits of water to cool different ends of the container. 
     Although in the embodiments described above, the longitudinal bores for the elongate heating elements extend the length of the mantle or subliner, in other embodiments, the longitudinal bores for the elongate heating elements may alternatively extend only partially the length of the mantle or subliner. For example, in one embodiment, the longitudinal bores may alternatively extend from the ram end of the mantle or subliner to approximately one-half (0.5) inches from the die end of the mantle or subliner. 
     Although in the embodiments described above, each fluid channel comprises a circumferentially-oriented, serpentine groove formed in the upper portion of the outer surface of the mantle, in other embodiments, one or both grooves may have other configurations. For example, in other embodiments, one or both grooves fluid channels may alternatively comprise a longitudinally-oriented, serpentine groove formed in the upper portion of the outer surface of the mantle. Those skilled in the art will understand that still other groove configurations are possible. Additionally, the grooves need not necessarily be serpentine, and in other embodiments, one or both grooves may alternatively have a non-serpentine configuration. 
     Although in the embodiments described above, the longitudinal bores for the elongate heating elements extend the length of the mantle or subliner, in other embodiments, the longitudinal bores for the elongate heating elements may alternatively extend only partially the length of the mantle or subliner. For example, in one embodiment, the longitudinal bores may alternatively extend from the ram end of the mantle or subliner to approximately one-half (0.5) inches from the die end of the mantle or subliner. 
     Although in the embodiments described above, the elongate heating elements are configured with die end heating sections and ram end heating sections, in other embodiments, the elongate heating elements may alternatively be configured with additional or fewer heating sections, and/or may alternatively be configured to heat along the entire length of the heating cartridge. 
     Although in the embodiments described above, the elongate heating elements in the vicinity of the lower die end zone and the lower ram end zone are described as being configured to be controlled by the operator to provide added temperature, it will be understood that these elongate heating elements are also configured to be controlled by the operator to provide reduced temperature. Similarly, although in the embodiment described above, the elongate heating elements in the vicinity of the upper die end zone and the upper ram end zone are described as being configured to be controlled by the operator to provide reduced temperature, it will be understood that these elongate heating elements are also configured to be controlled by the operator to provide added temperature. 
     Although in the embodiments described above, the bores for accommodating temperature sensors extend partially into the length of the mantle or subliner, in other embodiments, the bores may alternatively extend the full length of the mantle or subliner. In related embodiments, the temperature sensors may alternatively be “cartridge” type temperature sensors, and may alternatively comprise a plurality of temperature sensors positioned along their length. 
     Although in the embodiments described above, the first fluid is air, in other embodiments, one or more other suitable fluids may alternatively be used. For example, in other embodiments, the first fluid may be any of nitrogen and helium. In other embodiments, the first fluid may be cooled by a cooling apparatus prior to entering the first fluid channel. 
     Although embodiments have been described above with reference to the accompanying drawings, those of skill in the art will appreciate that variations and modifications may be made without departing from the scope thereof as defined by the appended claims.