WO2024165380A1

WO2024165380A1 - Extrusion die and extrusion system

Info

Publication number: WO2024165380A1
Application number: PCT/EP2024/052222
Authority: WO
Inventors: Mathias Geyer; Lasse LIMBACH
Original assignee: KraussMaffei Extrusion GmbH
Priority date: 2023-02-10
Filing date: 2024-01-30
Publication date: 2024-08-15
Also published as: DE102023103235A1

Abstract

The invention relates to an extrusion die (100), in particular a tubular extrusion die, for producing a hollow plastic profile, in particular a plastic pipe, the extrusion die comprising at least one melt channel (102), which extends between a melt inlet (104) and a melt outlet (106), and a nozzle and/or set of nozzles, wherein the melt outlet (106) is designed such that a plastic melt and/or the produced hollow plastic profile is transferred to the nozzle and/or the set of nozzles, wherein at least one portion of the melt channel (102) is substantially floatingly mounted and/or movable. The invention also relates to an extrusion system comprising at least one extruder and an extrusion die (100).

Description

Extrusion tool and extrusion system

The invention relates to an extrusion tool, in particular a pipe extrusion tool, for example a pipe head. The invention also relates to an extrusion system with such an extrusion tool.

Extrusion tools are usually installed downstream of an extruder arrangement, for example immediately, so that the melt provided by the extruder arrangement, in particular plastic melt, can be brought into a desired shape by the downstream extrusion tool. Flat nozzles, pipe tools, profiles, etc. are known as extrusion tools.

In the case of pipe extrusion tools, also known as pipe heads, it is also known to heat them radially inside and/or outside inside the housing, i.e. well in front of the nozzle, for example with the help of ceramic heating bands. In the case of large pipe heads in particular, the inside of the pipe head is heated with the help of a temperature control system that works with a temperature control medium. Such temperature control has the advantage that heat can not only be added to the melt, but also removed.

For example, from the document DE 10 2010 025 524 A1 a device for producing a hollow plastic profile is known, which has an extrusion tool with a melt channel, an extruder that feeds the melt channel with plastic melt and a suction device for sucking air through the interior of the profile against the direction of extrusion. The air guidance system can provide internal pipe cooling.

However, when producing multi-layer plastic products that have to be extruded from plastics with significantly different processing temperatures, the design of the known extrusion tools for pipe extrusion has some disadvantages. A major disadvantage lies in the general design of the extrusion tools. In the known design, the individual components are rigid connected to each other and are made of the same material. This means that permanent, clearly different temperature zones within the extrusion tool cannot be guaranteed. Consequently, multi-layer plastic products that are extruded from plastics with significantly different processing temperatures cannot be manufactured or can only be manufactured in a multi-stage process. It is known that there is a risk of plastics degradation and only limited formability of plastic melts if the individual plastic melt channels/lines are not thermally separated. Due to different thermal expansions, there is also a risk of damage to the extrusion tool if the melt-carrying components are rigidly designed to one another.

The invention is based on the object of structurally and/or functionally improving an extrusion tool mentioned at the beginning. The invention is also based on the object of structurally and/or functionally improving an extrusion system mentioned at the beginning. It is therefore an object of the present invention to provide an extrusion tool or an extrusion system which reduces or eliminates the disadvantages identified in connection with the prior art. In particular, it is an object of the present invention to provide a pipe extrusion tool with which plastic melts at different temperatures can be processed and damage to the extrusion tool or parts thereof, in particular due to thermal expansion, can be avoided.

The object is achieved with an extrusion tool having the features of claim 1. Furthermore, the object is achieved with an extrusion system having the features of claim 12. Advantageous embodiments and/or further developments are the subject of the subclaims.

One aspect relates to an extrusion tool, in particular for producing a hollow plastic profile. The plastic profile can be a plastic pipe, for example a multilayer pipe. The extrusion tool can be used and/or designed for use in an extrusion system. The extrusion tool can be a Pipe extrusion tool, such as a pipe head. The pipe extrusion tool can be a multi-layer pipe head.

The extrusion tool can comprise at least one melt channel. The at least one melt channel can also be referred to as a melt line. The extrusion tool can have multiple melt channels. The at least one melt channel can be designed to guide or direct and/or receive a plastic melt. For example, the extrusion tool can have exactly two melt channels or exactly three melt channels. The number of melt channels can correspond to the number of layers of the multilayer profile or multilayer pipe to be produced. The at least one melt channel can run or be designed to be straight, curved or spiral-shaped, at least in sections.

The at least one melt channel can run between a melt inlet and a melt outlet. The melt inlet can be designed for connection to an extruder, in particular an extruder outlet. The extrusion tool can have several melt inlets. For example, the extrusion tool can have exactly two melt inlets or exactly three melt inlets. The number of melt inlets can correspond to the number of layers of the multilayer profile or multilayer pipe to be produced. Each melt inlet can be assigned a melt channel. All melt channels can open into the melt outlet. The melt outlet can be designed such that the plastic melt and/or the plastic hollow profile produced can be output and/or transferred to a nozzle and/or a nozzle set. The extrusion tool can have the nozzle and/or the nozzle set. The nozzle and/or the nozzle set can be arranged at the melt outlet and/or attached there. The nozzle and/or the nozzle set can be exchangeable. The nozzle and/or the nozzle set can have a mandrel. The nozzle and/or the nozzle set can be designed to form and/or shape specific or different profile or pipe dimensions, such as pipe diameters. The nozzle set can include the nozzle and the mandrel. At least one section of the at least one melt channel can be mounted in a substantially floating manner. Additionally or alternatively, at least one section of the at least one melt channel can be designed to be movable, for example movable on one side and/or in the axial direction and/or longitudinal direction of the at least one melt channel. The mobility of the at least one melt channel can also be understood to mean thermal expansion and/or expandability of at least one section of the at least one melt channel. Furthermore, movable can also be understood to mean contraction and/or shrinkage. The at least one melt channel can be mounted in a substantially directly or indirectly floating manner and/or movable, for example movably mounted. The at least one melt channel can be designed, in particular by a floating mounting and/or movable mounting or by the mobility, to compensate for and/or enable expansion, in particular caused by heat. The at least one melt channel or the at least one section of the at least one melt channel can be designed and/or mounted such that it can expand, contract and/or displace at least in one direction, for example in and/or opposite to the flow direction and/or extrusion direction and/or axial direction and/or longitudinal direction of the at least one melt channel.

The extrusion tool can have at least one bearing. The at least one bearing can be designed to support the at least one melt channel in a substantially floating and/or movable manner, for example as described above and/or below. The at least one bearing can be designed as a support bearing or fixed-loose bearing. The at least one bearing can be designed such that there is little or no contact between components of different temperatures and/or they can move relative to one another. The at least one bearing and/or the at least one melt channel can be designed to compensate for and/or enable expansion and/or compensation of thermal expansion. The at least one bearing can have at least one or more, e.g. two, three, four or more, bearing elements. The bearing elements, e.g. two Bearing elements of the at least one bearing can be arranged on opposite sides of a melt channel section of the at least one melt channel. The bearing element(s) can be firmly connected to the at least one melt channel.

The at least one melt channel and/or the at least one bearing can be made, at least in sections, from a material that has a low thermal expansion coefficient. The thermal expansion coefficient can also be referred to as an expansion coefficient, such as a linear expansion coefficient, or can be this. The at least one melt channel and the at least one bearing can have different or identical thermal expansion coefficients. For example, the thermal expansion coefficient of the at least one melt channel can be lower or higher than the thermal expansion coefficient of the at least one bearing. Additionally or alternatively, the at least one bearing and a section of the extrusion tool that adjoins it, e.g. a housing section, can have different or identical thermal expansion coefficients. For example, the thermal expansion coefficient of the at least one bearing can be lower or higher than the thermal expansion coefficient of the section of the extrusion tool that adjoins it, e.g. a housing section. Additionally or alternatively, the at least one melt channel and at least one section of the extrusion tool adjoining it, e.g. housing section, can have different thermal expansion coefficients. For example, the at least one section of the at least one melt channel and at least one section of the extrusion tool adjoining it, e.g. housing section, can have different thermal expansion coefficients. For example, the thermal expansion coefficient of the at least one melt channel can be lower or higher than the thermal expansion coefficient of the section of the extrusion tool adjoining it, e.g. housing section. The section or housing section of the extrusion tool can be structural elements of the extrusion tool, in particular those surrounding the bearing. The thermal expansion coefficient can be between about 0.5 and about 30 [10' ⁶ /K], for example between about 10.5 and about 17 [10' ⁶ /K]. The thermal expansion coefficient can be chosen to be as small as possible. For example, the thermal expansion coefficient can be about 1.2 [10' ⁶ /K], about 11.2 [10' ⁶ /K], about 13.2 [10' ⁶ /K] or about 17 [10' ⁶ /K].

The at least one melt channel and/or the at least one bearing can be made at least in sections from metal. The metal can be, for example, a metal alloy such as steel, for example a stainless martensitic steel, stainless steel, Ni steel with iron-based alloy, or a stainless austenitic chromium-nickel-molybdenum steel.

The at least one melt channel and/or the at least one bearing can be made, at least in sections, from a material that is elastically deformable. The at least one bearing and/or the at least one melt channel can be flexible and/or bendable. The at least one bearing can comprise a sheet metal, for example a thin sheet metal, or can be designed as such. The at least one bearing can have an insulating property, at least in sections. The at least one melt channel can be designed as a melt tube.

A fit, for example a clearance fit, can be effectively provided between the at least one melt channel and the at least one bearing. Additionally or alternatively, a fit, for example a clearance fit, can be effectively provided between the at least one melt channel and at least one section of the extrusion tool adjacent to it, e.g. the housing section. Additionally or alternatively, a fit, for example a clearance fit, can be effectively provided between the at least one bearing and at least one section of the extrusion tool adjacent to it, e.g. the housing section. Alternatively or in addition to the fit, a groove structure, a notch structure or a recess can be provided. The section or housing section of the extrusion tool can be structural elements of the extrusion tool, in particular those surrounding the bearing. The at least one melt channel can be formed in one piece. The at least one melt channel can be formed in multiple parts, for example in two parts. The parts of the at least one melt channel can be designed to be displaceable relative to one another, for example essentially in the longitudinal direction of the at least one melt channel. The parts of the at least one melt channel can be designed to be displaceable into one another. An elastic element, for example a spring element and/or bellows, such as a folding bellows, can be effective and/or arranged between the parts of the at least one melt channel. This makes it possible to compensate for different length expansions. A fit and/or sealing surface(s) and/or seal can be effective and/or provided between the parts of the at least one melt channel. The fit and/or sealing surface(s) and/or seal can be effectively provided in a displaceable transition region of the parts. The seal can be a metallic seal. This can prevent plastic melt from escaping from a gap between the parts.

The at least one melt channel can be designed to be thermally separated at least in sections. The at least one melt channel can run through the extrusion tool in a thermally separated manner. Several, e.g. two, three or four, melt channels can be thermally separated from one another at least in sections. This can be achieved by thermal separation. This makes it possible to achieve different temperatures for the plastic melt moving through the melt channels and thus optimally influence the different plastic materials to be processed. It is therefore possible to feed plastic materials with very different temperatures into the extrusion tool after plasticizing and to keep them at this temperature evenly during material distribution, so that temperature equalization only occurs in the layered extrudate.

The at least one melt channel can be designed as a pipe or pipeline, at least in sections. The at least one melt channel can have a round or square cross-section. The extrusion tool can have at least one distribution element. For example, the extrusion tool can have several distribution elements, e.g. exactly two or exactly three distribution elements. The number of distribution elements can correspond to the number of layers of the multilayer profile or multilayer pipe to be produced. The at least one melt channel can be formed and/or limited at least in sections by a distribution element and/or a section, e.g. housing section, of the extrusion tool.

The at least one distribution element can be designed in one piece or in multiple parts, for example in two parts. For example, the at least one distribution element can comprise a pre-distribution element and a spiral distribution element. The pre-distribution element can have a main channel and/or at least one pre-distribution channel. The spiral distribution element can comprise at least one secondary channel. The at least one secondary channel can run out in a helical manner in the peripheral surface of the spiral distribution element. The main channel can merge into the at least one pre-distribution channel and/or the at least one secondary channel. The at least one pre-distribution channel can merge into the at least one secondary channel.

The at least one distribution element can be designed as a rotary distributor. The rotary distributor can be an axial rotary distributor. The rotary distributor can be essentially cylindrical, for example hollow cylindrical. The rotary distributor can be designed in one piece or in multiple pieces. The rotary distributor can have a main channel. The main channel can be an input channel, such as a melt input channel. The rotary distributor can have at least one secondary channel that is in a fluidic and/or fluid connection with the main channel, such as a fluid connection. The at least one secondary channel can run out in a helical manner in the peripheral surface of the rotary distributor. The main channel can merge into the at least one secondary channel. The at least one secondary channel can be an output channel, such as a melt output channel. The at least one secondary channel can be a rotary distributor channel. The rotary distributor can have several secondary channels. The several secondary channels can be fluidically connected to the main channel on the input side or can be in this open out. The multiple secondary channels can form a spiral arrangement. The plastic melt can be fed into the spiral distributor via the main channel. From the main channel, the plastic melt can be guided further into the at least one secondary channel or into the multiple secondary channels. In the at least one secondary channel or in the multiple secondary channels, the plastic melt can be brought into a homogeneous and/or hollow shape. The main channel and/or the at least one secondary channel or channels can be part of a melt channel and/or form and/or define it at least in sections. The main channel and/or the at least one secondary channel or channels and/or the at least one pre-distribution channel or channels can be designed as a bore or groove at least in sections.

The extrusion tool can have a housing. The housing can be made up of several parts. The housing can have several housing sections or housing parts. The at least one distribution element can be arranged within the housing. The at least one melt channel can be arranged within the housing.

The at least one melt channel and/or the at least one distribution element can be arranged and/or aligned substantially in the axial direction, in particular the extrusion direction.

The melt channels and/or melt streams can be brought together one after the other essentially in the axial direction, in particular the extrusion direction. The joining of individual melt channels and/or melt streams can be realized one after the other essentially in the axial direction, in particular the extrusion direction, and/or the radial direction, for example by means of an L- or T-shaped connecting arrangement or connecting piece.

At least two melt channels can merge into a common ring melt channel in the direction of the melt outlet. This ring melt channel can be thermally separated at least in sections. The ring melt channel can be essentially concentric to the extrusion direction or extrusion axis. The The ring melt channel can be an annular gap melt channel. The ring melt channel can be designed in such a way that an annular gap flow of the plastic melt can be generated. At least two melt flows can be brought together in the ring melt channel.

The respective thermal separation can be formed by a gap and/or cavity. The gap and/or cavity can be annular and/or spiral-shaped. The gap can be an annular gap, air gap or vacuum gap. The cavity can be a chamber, such as a hollow chamber and/or vacuum chamber. The gap and/or cavity can have an inlet or inlet and/or outlet or outlet for a temperature control medium. The respective thermal separation can additionally or alternatively be formed by an insulation element. The insulation element can be arranged completely or at least in sections within the gap or cavity. The insulation element can be arranged completely or at least in sections on the at least one melt channel, for example on a surface, such as a contact surface and/or at fastening points, such as screwing points, of the at least one melt channel. The insulation element can form and/or delimit the at least one melt channel at least in sections. The insulation element can be cylindrical and/or pot-shaped. The insulation element can be made of a material with a low thermal conductivity coefficient. Materials such as steel can be provided that have different thermal conductivity coefficients. The insulation element can be made of a metal such as steel or other alloys, plastic and/or insulating material, for example wool, such as mineral wool or glass wool, or at least comprise one of these. The insulating material can be an artificial and/or natural fiber insulating material. The insulation element can also comprise a natural material. In particular, the material of the insulation element can be designed as a poor heat conductor. The insulation element can be designed as an intermediate piece and/or connecting piece for at least one distribution element, for example for the first distribution element. The insulation element can be designed as an insulating sleeve or insulating bushing. The thermal separation and/or the insulation element can be designed as a coating, in particular an insulation coating. The coating can be provided at least in sections inside or outside the at least one melt channel. For example, the coating can be an inner coating or outer coating of the at least one melt channel. The at least one melt channel can be coated at least in sections with an insulation coating. The coating can be made of metal, such as steel or other alloys, and/or plastic. In particular, the material of the coating can be designed as a poor heat conductor or have a low thermal conductivity coefficient.

The insulation element or the insulation sleeve or insulation bushing can be arranged around at least one section of at least one melt channel. The insulation element or the insulation sleeve or insulation bushing can have at least one heating and/or cooling element. The heating and/or cooling elements can be controlled via temperature control devices. The heating and/or cooling elements can be designed as electrical and/or hydraulic heating and/or cooling elements. The heating element can be a heating band. The heating band can be a ceramic heating band, an aluminum heating band or a mica heating band.

The gap or cavity can be filled and/or fillable with a tempering medium, such as heating medium or coolant, for example with a gas such as air and/or with a fluid such as water and/or oil. A vacuum can essentially be provided and/or generated in the gap and/or cavity. The thermal separations, in particular the respective gaps, cavities, insulation elements, insulation sleeves or insulation bushings, can be provided with or connected to mutually independent tempering devices. For example, a tempering medium with a predetermined temperature can flow and/or be fed through each gap or cavity or through selected gaps or cavities in order to appropriately temper the plastic melt in the associated melt channel, such as to heat or cool it or to keep it at a predetermined temperature. A further aspect relates to an extrusion system. The extrusion system can be set up and/or designed to produce a hollow plastic profile, such as a plastic pipe, for example a multilayer pipe. The extrusion system can comprise an extrusion tool. The extrusion tool can be designed as described above and/or below. The extrusion system can further comprise at least one extruder. The at least one extruder can be a single-screw extruder or a twin-screw extruder. The extrusion system can provide an extruder for each melt inlet of the extrusion tool.

In summary and in other words, the invention thus results in, among other things, an extrusion tool, such as a pipe tool/pipe head/multi-layer pipe head, in which a different structure is provided, whereby the melt-carrying components can be mounted so that they can move relative to one another and/or can be made from materials with low expansion coefficients (thermal expansion coefficients) and/or can be designed so that expansion can be compensated. For example, a floating mounting of the melt line(s) (melt channel(s) can be provided for this purpose. The structure can also ensure that the various plastics remain separate from one another with their different temperatures for as long as possible. This can be done by thermally separating the layers or plastic melts, by tempering the layers or plastic melts and/or by bringing the layers or plastic melts together in the tool as late as possible.

The invention enables materials or plastic melts to be processed within a tool that have to be processed at different temperatures for technical reasons. Damage to the components, especially in continuous operation, can be avoided. A longer service life is made possible. A multi-stage extrusion process can be omitted because only one tool is required. A larger tolerance range and thus lower production costs can be achieved. The economic throughput can be improved. The tool is also suitable for the production of large pipes. suitable. Covering a wide pipe dimension window per tool can be made possible. Furthermore, a large processing window of different plastics can be made possible.

In the following, embodiments of the invention are described in more detail with reference to a figure, which shows schematically and by way of example:

Fig. 1 is a sectional view of an extrusion tool;

Fig. 2 a variant of a floating / movable bearing; and

Fig. 3 another variant of a floating / movable bearing.

Fig. 1 shows a sectional view of an extrusion tool 100. The extrusion tool 100 is designed as a pipe extrusion tool, for example as a pipe head, for producing a hollow plastic multilayer pipe. In the present embodiment, the extrusion tool 100 can be fed with three plastic melts in order to produce a three-layer plastic pipe.

The extrusion tool 100 comprises at least one melt channel 102, which runs between a melt inlet 104 and a melt outlet 106. At least one section of the melt channel 102 is mounted in a substantially floating/movable manner. For this purpose, the extrusion tool has at least one bearing 108, which is designed to mount the at least one melt channel 102 in a substantially floating/movable manner.

The at least one bearing 108 is designed such that in particular the at least one melt channel 102 and a section of the extrusion tool 100 or the housing/housing section of the extrusion tool 100 are movable relative to one another and an expansion and/or compensation of thermal expansions is compensated. In the present exemplary embodiment, the at least one bearing 108 has two bearing elements 110 and 112. The two bearing elements 110 and 112 of the at least one bearing 108 are arranged on opposite sides of a melt channel section 114 of the at least one melt channel 102. Furthermore, the two bearing elements 110 and 112 are firmly connected to the at least one melt channel 102. The bearing elements 110, 112 are each designed to be movable or displaceable relative to a section of the extrusion tool 100 or to the housing/housing section of the extrusion tool 100. The section or housing section of the extrusion tool can, in particular, have bearing elements 110, 112 surrounding,

construction elements. The at least one bearing 108 is thus designed as a support bearing. Alternatively, a bearing element, e.g. the bearing element 110, can be axially fixed, e.g. relative to the section of the

Extrusion tool 100 or to the housing / housing section of the

Extrusion tool 100. The bearing 108 can thus alternatively be designed as a fixed-loose bearing. The at least one melt channel 102 can thus expand or move due to thermal expansion essentially in the longitudinal direction or against the direction of extrusion. This allows compensation of thermal expansion and prevents damage to the at least one melt channel 102 or the housing or sections/elements of the extrusion tool 100.

Furthermore, the at least one melt channel 102 is designed to be thermally separated at least in sections. In the present exemplary embodiment, the thermal separation is realized by a gap or cavity 116. In addition, the at least one melt channel 102 is surrounded in sections by at least one insulation element 118 designed as an insulation sleeve. The insulation sleeve can have one or more cooling and/or heating elements. The heating element can be a heating band. The heating band can be a ceramic heating band, an aluminum heating band or a mica heating band.

For temperature control, a temperature control medium, such as heating medium or coolant, for example a gas, such as air, and/or a fluid, such as Water and/or oil can be fed in by means of a temperature control device. Alternatively, a vacuum can be provided and/or generated in the cavity 116.

Fig. 2 shows a variant of a floating / movable bearing 200. In contrast to the embodiment according to Fig. 1, in the present embodiment according to Fig. 2 the at least one melt channel 102 is formed in several parts, here in two parts, and has a first part 202 and a second part 204.

The two parts 202 and 204 of the at least one melt channel 102 are designed to be displaceable relative to one another, essentially in the longitudinal direction of the at least one melt channel 102. Furthermore, the two parts 202 and 204 of the at least one melt channel 102 are designed to be displaceable into one another, wherein the second part 204 is displaceable into the first part 202.

Between the two parts 202, 204 of the at least one melt channel 102, a fit or sealing surface 206 is effectively provided in sections so that the plastic melt cannot escape through a gap.

Furthermore, reference is made in particular to Fig. 1 and the associated description.

Fig. 3 shows a further variant of a floating / movable bearing 300. The at least one melt channel 102 is also formed in two parts according to this embodiment and has a first part 302 and a second part 304.

In contrast to the embodiment according to Fig. 2, the two parts 302 and 304 of the present embodiment according to Fig. 3 are not displaceable into one another, but are only designed to be displaceable relative to one another, essentially in the longitudinal direction of the at least one melt channel 102.

An elastic element 306 is effectively arranged between the two parts 302, 304 of the at least one melt channel 102. The elastic element 306 is designed as Bellows. Alternatively, the elastic element 306 can be designed as a spring element. The bellows is flexible and allows the two parts 302, 304 to move relative to each other.

Furthermore, reference is made in particular to Figs. 1 and 2 and the associated description.

The term "can" refers in particular to optional features of the invention. Accordingly, there are also further developments and/or embodiments of the invention which additionally or alternatively have the respective feature or features.

If necessary, isolated features can also be selected from the combinations of features disclosed here and used in combination with other features to define the subject matter of the claim, dissolving any structural and/or functional connection that may exist between the features.

List of reference symbols

Extrusion tool

Melt channel

Melt inlet

Melt outlet

Storage

Bearing element

Pipe section

Gap / cavity

Insulation element / insulation sleeve

Bearing first part of the melt channel second part of the melt channel fit / sealing surface

Bearing first part of the melt channel second part of the melt channel elastic element

Claims

Patent claims

1. Extrusion tool (100), in particular a pipe extrusion tool, for producing a hollow plastic profile, in particular a plastic pipe, comprising at least one melt channel (102) which runs between a melt inlet (104) and a melt outlet (106) and a nozzle and/or a nozzle set, wherein the melt outlet (106) is designed such that a plastic melt and/or the hollow plastic profile produced is transferred to the nozzle and/or the nozzle set, characterized in that at least a section of the melt channel (102) is essentially floating and/or movable.

2. Extrusion tool (100) according to claim 1, characterized in that the extrusion tool (100) has at least one bearing (108, 200, 300) which is designed to mount the at least one melt channel (102) in a substantially floating and/or movable manner.

3. Extrusion tool (100) according to claim 2, characterized in that the at least one bearing (108, 200, 300) is designed as a support bearing or as a fixed-loose bearing.

4. Extrusion tool (100) according to at least one of the preceding claims, characterized in that the at least one melt channel (102) and/or the at least one bearing (108, 200, 300) is made at least in sections from a material having a low thermal expansion coefficient.

5. Extrusion tool (100) according to at least one of the preceding claims, characterized in that the at least one melt channel (102) and the at least one bearing (108, 200, 300) and/or the at least one melt channel (102) or its at least one section and at least one section of the extrusion tool (100) adjacent thereto, such as the housing section, has different thermal expansion coefficients.

6. Extrusion tool (100) according to at least one of the preceding claims, characterized in that the at least one melt channel (102) and/or the at least one bearing (108, 200, 300) is made at least in sections from a material that is elastically deformable.

7. Extrusion tool (100) according to at least one of the preceding claims, characterized in that the at least one bearing (108, 200, 300) and/or the at least one melt channel (102) is flexible and/or bendable.

8. Extrusion tool (100) according to at least one of the preceding claims, characterized in that the at least one melt channel (102) is designed in several parts, in particular in two parts, wherein the parts (202, 204, 302, 304) of the at least one melt channel (102) are designed to be displaceable relative to one another, in particular substantially in its longitudinal direction.

9. Extrusion tool (100) according to claim 8, characterized in that the parts (202, 204) of the at least one melt channel (102) are designed to be displaceable into one another.

10. Extrusion tool (100) according to claim 8 or 9, characterized in that a fit (206) and/or sealing surface (206) and/or seal is effective and/or provided between the parts (202, 204) of the at least one melt channel (102).

11. Extrusion tool (100) according to at least one of the preceding claims 8 to 10, characterized in that between the parts (302, 304) of the at least one melt channel (102) an elastic element (306), in particular a spring element and/or bellows, such as a folding bellows, is effective and/or arranged.

12. Extrusion tool (100) according to at least one of the preceding claims, characterized in that the at least one melt channel (102) is designed to be thermally separated at least in sections, preferably the at least one melt channel (102) runs through the extrusion tool in a thermally separated manner.

13. Extrusion tool (100) according to at least one of the preceding claims, characterized in that the extrusion tool (100) has a plurality of melt channels (102) and the plurality, preferably two, three or four, melt channels (102) are thermally separated from one another at least in sections.

14. Extrusion tool (100) according to claim 2, characterized in that the at least one bearing (108) is designed such that the at least one melt channel (102) and a portion of the extrusion tool (100), the housing or a housing portion of the extrusion tool (100) are movable relative to one another and an expansion and/or a compensation of thermal expansions is compensated.

15. Extrusion tool (100) according to claim 3, characterized in that the at least one bearing (108) has two bearing elements (110, 112), wherein the two bearing elements (110, 112) are arranged on opposite sides of a melt channel section (114) of the at least one melt channel (102) and preferably the two bearing elements (110, 112) are firmly connected to the at least one melt channel (102) and are each designed to be movable or displaceable relative to a section of the extrusion tool (100), to the housing or to a housing section of the extrusion tool (100).

16. Extrusion system comprising at least one extruder; and an extrusion tool (100) according to at least one of the preceding claims.