Strand generator for generating material strands, and method for producing a strand generator of this kind

Abstract

The application relates to a strand generator for generating material strands, comprising a main body (2) and at least one wear-protection element (3) which is secured to the main body (2) by means of at least one layer (10, 12) of at least one hard solder material (WH1, WH2). The strand generator has high wear resistance and a long service life. The application also relates to a method for producing a strand generator for generating material strands.

Description

[0001] Strand producer for producing material strands and method for producing such a strand producer

[0002] This patent application claims priority from German patent application DE 10 2023 206 824.9, the contents of which are incorporated herein by reference.

[0003] The invention relates to a strand producer for producing material strands, in particular plastic material strands. Furthermore, the invention relates to a method for manufacturing a strand producer for producing material strands, in particular plastic material strands.

[0004] The use of strand makers in granulation systems is well known. A strand maker is used to produce strands of material by forcing the material through channels, for example, using an extruder.

[0005] Rotating pelletizing knives on the strand maker reduce the resulting strands of material into pellets. The strand maker is subject to high mechanical stress due to the flowing material and the pelletizing knives.

[0006] The invention is based on the object of creating a strand producer for producing material strands which has a high wear resistance and a long service life.

[0007] This object is achieved by a strand producer having the features of claim 1. The at least one wear protection element is fastened to the base body by means of at least one layer of at least one brazing material. The at least one wear protection element is thus connected to the base body by brazing. This creates a brazing connection between the base body and the at least one wear protection element. The brazing connection can be formed or created at a comparatively low temperature, so that the wear protection element material of the at least one wear protection element and / or the base body material of the base body is not impaired. In particular, the wear protection element material does not lose any of its hardness, so that the at least one wear protection element is extremely wear-resistant. The strand producer thus has high wear resistance and a long service life.

[0008] The at least one wear protection element serves to produce the material strands. The at least one wear protection element comprises a plurality of through-openings. The material strands flow through the through-openings during operation of the strand producer. The at least one wear protection element is arranged on a side of the base body facing a granulating blade. The at least one wear protection element or the respective wear protection element is preferably plate-shaped. The strand producer preferably comprises a plurality of wear protection elements that together form a ring or a circle. The at least one wear protection element is designed, for example, as a wear protection segment.

[0009] The base material is, in particular, austenitic, ferritic, duplex, martensitic, and / or stainless. The base material is, in particular, a high-alloy stainless steel. The base material is, for example, a material according to the material data sheets 1.4313, 1.4418, 1.4542, 1.4545, or 1.4548. The base material comprises, in particular, at least one of the following components:

[0010] Carbon C, in particular from 0 wt% to 0.35 wt%, in particular from 0.01 wt% to 0.07 wt%,

[0011] Nickel Ni, in particular from 0 wt% to 100 wt%, in particular from 1 wt% to 38 wt%, in particular from 2 wt% to 10 wt%, Chromium Cr, in particular from 0 wt% to 29 wt%, in particular from 0.5 wt% to 26 wt%, in particular from 12 wt% to 17.5 wt%,

[0012] Molybdenum Mo, in particular from 0 wt% to 28 wt%, in particular from 0.1 wt% to 5 wt%, and in particular from 1 wt% to 2.5 wt%,

[0013] Copper Cu, in particular from 0 wt% to 67 wt%, in particular from 0.1 wt% to 10 wt%, in particular from 1 wt% to 5 wt%, Manganese Mn, in particular from 0 wt% to 1.5 wt%,

[0014] Niobium Nb, in particular from 0 wt% to 0.5 wt%, and iron Fe, in particular from 1 wt% to 34 wt%.

[0015] The base material, for example, is a nickel-based material. This base material includes at least one of the following components:

[0016] Nickel Ni, in particular from 38 wt.% to 100 wt.%, chromium Cr, in particular from 0.7 wt.% to 29 wt.%, molybdenum Mo, in particular from 2.4 wt.% to 28 wt.%, copper Cu, in particular from 1.6 wt.% to 67 wt.%, and iron Fe, in particular from 1 wt.% to 34 wt.%. The wear protection element material is in particular a ferro-titanite material. The wear protection element material is in particular selected from the materials Nikrol28 and Nikrodur. Ferro-Titanit is a trademark of Deutsche Edelstahlwerke Speciality Steel GmbH & Co. KG.

[0017] For a hardness H of the wear protection element material, the following applies in particular: 58 HRC < H < 70 HRC, in particular 61 HRC < H < 69 HRC, and in particular 64 HRC < H < 68 HRC.

[0018] The wear protection element material comprises in particular at least one of the following components:

[0019] Titanium carbide TiC, in particular from 29 wt% to 34 wt%, in particular from 30 wt% to 33 wt%,

[0020] Chromium Cr, in particular from 2 wt.% to 20 wt.%, in particular from

[0021] 13 wt% to 18 wt%,

[0022] Cobalt Co, in particular from 7 wt% to 11 wt%, in particular from 8 wt% to 10 wt%,

[0023] Nickel Ni, in particular from 1 wt% to 18 wt%, in particular from 2 wt% to 16 wt%,

[0024] Molybdenum Mo, in particular from 1 wt% to 8 wt%, in particular from 2 wt% to 7 wt%,

[0025] Carbon C, in particular from 0.3 wt% to 1 wt%, in particular from 0.4 wt% to 0.9 wt%, and

[0026] Iron Fe.

[0027] The brazing material, for example, is a Nicuman material. Nicuman is a trademark of Morgan Advances Materials PLC. The brazing material is, for example, Nicuman 23 or Nicuman 37 (AMS 4764). Nicuman 23, for example, contains 67.5 wt% copper, 23.5 wt% manganese, and 9 wt% nickel. Nicuman 37, for example, contains 52.5 wt% copper, 38 wt% manganese, and 9.5 wt% nickel.

[0028] A strand producer according to claim 2 ensures high wear resistance and a long service life. The intermediate layer formed from the buffer material is arranged between the first layer of the at least one brazing material and the second layer of the at least one brazing material. The first layer of the at least one brazing material is thus connected to the base body and the intermediate layer, whereas the second layer of the at least one brazing material is connected to the intermediate layer and the at least one wear protection element. The intermediate layer reduces stresses in the brazing connection between the base body and the at least one wear protection element. The base body material and the wear protection element material expand to different extents when the temperature changes, for example when the strand producer is put into operation.The resulting stresses are reduced by the buffer material, thereby reducing the mechanical stress on the brazing joint, the base body, and / or the at least one wear protection element. The brazing material of the first layer and the brazing material of the second layer can be identical or different.

[0029] The buffer material comprises in particular at least one of the following components: copper Cu, in particular at least 99 wt.%, in particular at least

[0030] 99.9% by weight,

[0031] Nickel Ni, in particular at least 99 wt%, in particular at least 99.9 wt%.

[0032] A strand producer according to claim 3 ensures high wear resistance and a long service life. Because the melting temperature Tp of the buffer material is higher than the melting temperature TH of the respective brazing material, the brazing material melts earlier than the buffer material during the strand producer's production. During the strand producer's production, the temperature can thus be adjusted so that the brazing material is completely molten, whereas the buffer material only melts. This achieves an optimal brazing bond between the base body material and the buffer material, as well as between the wear protection element material and the buffer material.

[0033] For a melting temperature difference AT = Tp - TH the following applies in particular: 10°C < AT < 1000°C, in particular 200°C < AT < 800°C, and in particular 400°C < AT < 600°C.

[0034] A strand producer according to claim 4 ensures high wear resistance and a long service life. Because the buffer material is more ductile than the respective brazing material, the buffer material can deform plastically comparatively better and reduce stresses due to different thermal expansions of the base body material, the brazing material and / or the wear protection element material. The ductility can be determined or quantified, for example, in a tensile test according to DIN EN ISO 6892-1 (metal tensile test) by determining the elongation at break and / or the reduction in area at break. The higher the ductility of the material, the higher the elongation at break and / or the reduction in area at break. The buffer material therefore has a higher elongation at break and / or a higher reduction in area at break than the at least one brazing material.

[0035] A strand producer according to claim 5 ensures high wear resistance and a long service life. Because the elongation at break of the buffer material is greater than the elongation at break of the respective brazing material, the buffer material is more ductile than the brazing material. As a result, the buffer material can reduce stresses due to different thermal expansions of the base body material, the brazing material and / or the wear protection element material. For an elongation at break Ap of the buffer material, the following applies in particular: 10% < Ap < 180%, in particular 20% < Ap < 120%, and in particular 30% < Ap < 70%. The elongation at break Ap of the buffer material is determined in particular in the annealed state. The elongation at break Ap can be determined, for example, in a tensile test according to DIN EN ISO 6892-1 (tensile test metal).For a ratio VA of a breaking elongation AH of the respective brazing material to the breaking elongation Ap of the buffer material, the following applies in particular: 0.05 < VA < 1, in particular 0.1 < VA < 0.9, and in particular 0.2 < VA < 0.8.

[0036] A strand producer according to claim 6 ensures high wear resistance and a long service life. The respective brazing material is, in particular, a copper-based material or a silver-based material. The brazing material, in particular, does not comprise the components boron, silicon, titanium, and carbon. Preferably, the at least one brazing material comprises at least one of the following components:

[0037] Copper Cu, in particular from 10 wt% to 90 wt%, in particular from 30 wt% to 80 wt%, and in particular from 50 wt% to 70 wt%,

[0038] Manganese Mn, in particular from 20 wt% to 40 wt%,

[0039] Nickel Ni, in particular from 8 wt% to 10 wt%,

[0040] Silver Ag, in particular from 10 wt% to 85 wt%, in particular from 20 wt% to 65 wt%, and in particular from 30 wt% to 50 wt%, and

[0041] Zinc Zn, in particular from 5 wt% to 40 wt%, in particular from 10 wt% to 40 wt%, and in particular from 20 wt% to 30 wt%.

[0042] The at least one brazing material has a melting temperature TH at normal pressure (1.01325 bar or 1,013.25 hPa), whereby in particular: 700°C < TH < 1,000°C, in particular 750°C < TH < 980°C, and in particular 800°C < TH < 960°C.

[0043] A strand producer according to claim 7 ensures wear resistance and a long service life. The thickness DH ensures a strong brazing connection. The thickness DH of the at least one layer of the at least one brazing material is in particular less than a thickness Dp of an intermediate layer of a buffer material. The thickness DH is in particular an average value of the thickness of the respective layer of the at least one brazing material. The thickness DH is determined, for example, by means of a scanning electron microscope. The thickness DH of a first layer of the at least one brazing material and the thickness DH of a second layer of the at least one brazing material can be identical or different. The intermediate layer of the buffer material is in particular arranged between the first layer and the second layer.

[0044] A strand producer according to claim 8 ensures high wear resistance and a long service life. The buffer material enables a strong connection and a reduction of stresses due to different thermal expansions of the base body material, the at least one brazing material, and / or the wear protection element material. For this purpose, the buffer material is more ductile than the at least one brazing material.

[0045] A strand producer according to claim 9 ensures high wear resistance and a long service life. The thickness Dp of the intermediate layer enables compensation of stresses due to different thermal expansions of the base body material, the at least one brazing material, and / or the wear protection element material. The thickness Dp of the intermediate layer is, in particular, greater than a respective thickness DH of a layer of the at least one brazing material. The thickness Dp is, in particular, an average value of the thickness of the intermediate layer. The thickness Dp is determined, for example, using a scanning electron microscope.

[0046] The invention is further based on the object of creating a method for producing a strand producer for producing material strands that has high wear resistance and a long service life. This object is achieved by a method having the features of claim 10. The advantages of the method according to the invention correspond to the advantages of the strand producer according to the invention. The method according to the invention can be further developed, in particular, with at least one feature that is described in connection with the strand producer according to the invention. By melting and cooling the at least one brazing material, a brazing connection is created between the base body and the at least one wear protection element.The brazing joint is created, in particular, in a vacuum or in a protective gas atmosphere, or using a flux and / or by applying a contact force to the assembly comprising the base body, the at least one layer of the at least one brazing material, and the at least one wear protection element. The contact force relative to the joining surface is, for example, 0.005 N / mm. 2 . The brazing joint is preferably produced in a high vacuum, in particular at a pressure of at most 10' 3 mbar, especially at a pressure of not more than 10' 4 mbar, and in particular at a pressure of not more than 10' 5 mbar.

[0047] A method according to claim 11 ensures the production of a strand producer with high wear resistance and a long service life. Preferably, the same brazing material is used for the first layer and the second layer. Preferably, the arrangement is produced such that the first layer of the at least one brazing material, the intermediate layer of the buffer material, and the second layer of the at least one brazing material are arranged between the base body and the at least one wear protection element, such that the buffer material is arranged between the layers of the at least one brazing material. Preferably, the buffer material and / or the at least one brazing material is in the form of a foil. As a result, the layers and / or the intermediate layer can be formed simply by arranging foils next to one another and / or one above the other.

[0048] A method according to claim 12 ensures the production of a strand producer with high wear resistance and a long service life. The minimum temperature T m This ensures that the at least one brazing material melts completely and is molten. This ensures that the at least one brazing material is distributed optimally between the base body and the at least one wear protection element, in particular between the base body and the intermediate layer, as well as between the intermediate layer and the at least one wear protection element. The minimum temperature T m in is in particular higher than a melting temperature TH of at least one brazing material and lower than a melting temperature Tp of the buffer material. The minimum temperature T mThis ensures that at least one brazing material melts completely and that an oxide layer of the base body is dissolved, so that the base body material acquires high diffusivity. Heating takes place up to a brazing temperature that lies between the minimum temperature T m in and a maximum temperature T max.

[0049] A method according to claim 13 ensures the production of a strand producer with high wear resistance and a long service life. The maximum temperature T ma x is in particular higher than a melting temperature TH of at least one brazing material and lower than a melting temperature Tp of the buffer material. Due to the maximum temperature T ma x prevents the buffer material from melting completely. Heating takes place up to a brazing temperature that lies between the minimum temperature T m in and the maximum temperature T max lies.

[0050] A method according to claim 14 ensures the production of a strand producer with high wear resistance and a long service life. Because the melting temperature Tp of the buffer material is higher than the melting temperature TH of the at least one brazing material, an optimal brazing connection is achieved. A brazing temperature lies between the melting temperature TH and the melting temperature Tp, so that the at least one brazing material melts completely, but the buffer material does not melt, or only partially.

[0051] A method according to claim 15 ensures the production of a strand producer with high wear resistance and a long service life. The brazing temperature TL is preferably maintained for at least 15 minutes, in particular at least 30 minutes, and in particular at least 45 minutes. The brazing temperature TL is in particular maintained for a maximum of 120 minutes.

[0052] Further features, advantages, and details of the invention will become apparent from the following description of an exemplary embodiment. It shows:

[0053] Fig. 1 is a plan view of a strand producing machine for producing material strands with a base body and wear protection elements attached thereto, Fig. 2 is a section through the strand producing machine along the section line II-II in Fig. 1,

[0054] Fig. 3 is a detailed view of the strand generator in area III according to Fig. 2,

[0055] Fig. 4 a detailed view of the connection between the wear protection element and the base body in area IV according to Fig. 3,

[0056] Fig. 5 is a schematic representation of a method for manufacturing the strand generator in Fig. 1, and

[0057] Fig. 6 shows a time course of a temperature during the production of the strand generator.

[0058] The strand producer 1 shown in Fig. 1 is used to produce material strands, in particular plastic material strands. The strand producer 1 comprises a base body 2 and several wear protection elements 3 attached thereto. The base body 2 comprises an inner region 4, a central region 5, and an outer region 6.

[0059] The strand producer 1 comprises a first side E, which faces an extruder during operation, and a second side G, which faces a pelletizing blade during operation. The wear protection elements 3 are arranged and fastened in a ring shape on the second side G to the base body 2. Through-openings 8 are formed in the wear protection elements 3, and through-openings 8' are formed in the base body 2, which are each aligned with one another. The through-openings 8 and 8' form channels 7, which run from the first side E to the second side G and serve to produce the material strands.

[0060] The base body 2 is made of a WG base body material. The WG base body material is, for example, a stainless steel according to one of the material data sheets 1.4313, 1.4418, 1.4542, 1.4545, or 1.4548.

[0061] The wear protection elements 3 are made of a wear protection element material WL. The wear protection element material WL is, for example, a ferro-titanite material. The ferro-titanite material is, in particular, the material Nikro 128 or the material Nikrodur.

[0062] The wear protection elements 3 are attached to the base body 2 by means of a respective brazing connection 9. The brazing connection 9 is illustrated in Fig. 4. The brazing connection 9 comprises a first layer 10 of a brazing material WHI, an intermediate layer 11 of a buffer material Wp, and a second layer 12 of the brazing material WH2. The brazing materials WHI and WH2 can be identical or different. The brazing materials WHI and WH2 are generally referred to below as brazing material WH.

[0063] The first layer 10 has a first thickness Dm perpendicular to a surface of the base body 2 or the respective wear protection element 3. Correspondingly, the second layer 12 has a second thickness DH2 perpendicular to the surface of the base body 2 or the respective wear protection element 3. The following applies: 0.01 mm < Dm < 0.3 mm, in particular 0.03 mm < Dm < 0.25 mm, and in particular 0.05 mm < Dm < 0.2 mm. Correspondingly, the following applies: 0.01 mm < DH2 < 0.3 mm, in particular 0.03 mm < DH2 < 0.25 mm, and in particular 0.05 mm < DH2 < 0.2 mm. The thicknesses Dm and DH2 can be identical or different.

[0064] The first layer 10 connects the base body 2 with the intermediate layer 11. The second layer 12 connects the intermediate layer 11 with the respective wear protection element 3.

[0065] The intermediate layer 11 has a thickness Dp perpendicular to the surface of the base body 2 of the respective wear protection element 3, where: 0.01 mm < Dp < 2 mm, in particular 0.05 mm < Dp < 1.5 mm, and in particular 0.1 mm < Dp < 1 mm.

[0066] The brazing material WH has a melting point TH at atmospheric pressure. The following applies in particular to the melting point TH: 700°C < TH < 1,000°C, in particular 750°C < TH < 980°C, and in particular 800°C < TH < 960°C. The brazing material WH is in particular a material based on silver and / or copper. The brazing material WH comprises at least one component selected from copper, manganese, nickel, silver, and zinc. The brazing material WH is preferably the material Nicuman 23 or Nicuman 37 (AMS 4764). The material Nicuman 23 comprises, for example, 67.5 wt.% copper, 23.5 wt.% manganese, and 9 wt.% nickel. The melting point of Nicuman 23 is 955°C. The material Nicuman 37, for example, contains 52.5 wt% copper, 38 wt% manganese, and 9.5 wt% nickel. The melting point (TH) of Nicuman 37 is 925°C.

[0067] The buffer material Wp is more ductile than the brazing material WH. In particular, the buffer material Wp has a breaking elongation that is greater than the breaking elongation of the brazing material WH. The buffer material Wp has a melting point Tp at atmospheric pressure, where Tp > TH applies. The buffer material Wp comprises at least one component selected from copper and nickel. Preferably, the buffer material Wp comprises at least 99.9 wt.% copper. The buffer material Wp formed as copper has a melting point Tp of 1,085°C at atmospheric pressure.

[0068] Ductility can be determined or quantified, for example, in a tensile test according to DIN EN ISO 6892-1 (metal tensile test) by determining the elongation at break and / or the reduction in area at break. The higher the ductility of the material, the higher the elongation at break and / or the reduction in area at break. For an elongation at break Ap of the buffer material Wp, the following applies in particular: 10% < Ap < 180%, in particular 20% < Ap < 120%, and in particular 30% < Ap < 70%. The elongation at break Ap of the buffer material Wp is determined in particular in the annealed condition. The elongation at break Ap can be determined, for example, in a tensile test according to DIN EN ISO 6892-1 (metal tensile test). For a ratio VA of a breaking elongation AH of the brazing material WH TO the breaking elongation Ap of the buffer material Wp, the following applies in particular: 0.05 < VA < 1, in particular 0.1 < VA < 0.9, and in particular 0.2 < VA < 0.8.

[0069] When the strand producer 1 is started up or operated, the base body 2 and the wear protection elements 3 heat up due to the hot material from which the material strands are to be produced. The base body material WG, the brazing material WH, and the wear protection element material WL expand differently as a result of the heating or temperature change, causing stresses to arise in the brazing joint 9. These stresses are absorbed and reduced by the intermediate layer 11, thus reducing the mechanical stress on the brazing joint 9.

[0070] The following describes the production of the strand generator 1:

[0071] In a step Si, the base body 2 and the wear protection elements 3 are provided.

[0072] In a subsequent step S2, the first layer 10 of the brazing material WH is applied to the second side G of the base body, followed by the intermediate layer 11 of the buffer material Wp, and then the second layer 12 of the brazing material WH. The brazing material WH and the buffer material Wp are formed as foils. The brazing material WH has a foil thickness corresponding to the thickness DH. Accordingly, the buffer material Wp has a foil thickness corresponding to the thickness Dp. Finally, the wear protection elements 3 are applied to the second layer 12 of the brazing material WH.

[0073] In a third step S3, the assembly comprising the base body, the first layer 10 of the brazing material WH, the intermediate layer 11 of the buffer material Wp, the second layer 12 of the brazing material WH, and the wear protection elements 3 is heated to a brazing temperature TL, so that the brazing material WH completely melts and becomes molten. Heating preferably takes place in a vacuum furnace, i.e., in a vacuum, particularly in a high vacuum. Preferably, a contact force is exerted on the wear protection elements 3 during heating. The brazing temperature TL lies between a minimum temperature T m in and a maximum temperature T ma x. The following applies: TH < T m in < TL < T ma x < Tp. For the minimum temperature T m in particular applies: T m in > 980 °C, especially Tmin > 1,000 °C, and especially T m in > 1,020 °C. Furthermore, T m in < T ma x. For the maximum temperature Tma x applies in particular: T max < 1,070 °C, especially T max < 1,050 °C, and especially T max < 1,030 °C. Due to the maximum temperature T max This ensures that an oxide layer is removed from the base material WG and that the base material WG exhibits high diffusivity. The holding time at the brazing temperature TL, for example, is 30 minutes.

[0074] Because Tp > T max and TH < T m In this case, the brazing material WH melts completely at the brazing temperature TL, whereas the buffer material Wp only partially melts. This creates an optimal bond between the base body material WG and the buffer material Wp, as well as between the wear protection element material WL and the buffer material Wp.

[0075] In a fourth step S4, the assembly is cooled so that the brazing material WH solidifies again and the brazing joint 9 forms. Fig. 6 illustrates the temperature curve as a function of time t during heating in step S3 and cooling in step S4.

[0076] Because the brazing temperature TL is comparatively low, the wear protection element material WL and the base body material WG are not affected during the attachment of the wear protection elements 3 to the base body 2. The wear protection element material WL of the wear protection elements 3 attached to the base body 2 has a hardness H, where in particular: 58 HRC < H < 70 HRC, in particular 61 HRC < H < 69 HRC, and in particular 64 HRC < H < 68 HRC. The strand producer 1 is used in granulating devices in which the produced material strands are cut into granules by rotating granulating blades.

Claims

Patent claims 1. Strand producer for producing material strands with - a base body (2) and - at least one wear protection element (3), characterized in that the at least one wear protection element (3) is fastened to the base body (2) by means of at least one layer (10, 12) of at least one brazing material (WHI, WH2).

2. Strand producer according to claim 1, characterized in that a first layer (10) of the at least one brazing material (WHI, WIE), an intermediate layer (11) of a buffer material (Wp) and a second layer (12) of the at least one brazing material (WHI, WH2) are arranged between the base body (2) and the at least one wear protection element (3).

3. Strand producer according to claim 2, characterized in that the buffer material (Wp) has a melting temperature Tp and the at least one brazing material (WHI, WH2) has a melting temperature TH at normal pressure, where: Tp > TH.

4. Strand producer according to claim 2 or 3, characterized in that the buffer material (Wp) is more ductile than the at least one brazing material (WHI, WH2).

5. Strand producer according to at least one of claims 2 to 4, characterized in that that the buffer material (Wp) has an elongation at break that is greater than an elongation at break of at least one brazing material (WHI, WH2).

6. Strand producer according to at least one of the preceding claims, characterized in that the at least one brazing material (WHI, WH2) comprises at least one component selected from copper, manganese, nickel, silver and zinc.

7. Strand producer according to at least one of the preceding claims, characterized in that the at least one layer (10, 12) of the at least one brazing material (WHI, WH2) each has a thickness DH, where: 0.01 mm < DH < 0.3 mm, in particular 0.03 mm < DH < 0.25 mm, and in particular 0.05 mm < DH < 0.2 mm.

8. Strand producer according to at least one of claims 2 to 7, characterized in that the buffer material (Wp) comprises at least one component selected from copper and nickel.

9. Strand producer according to at least one of claims 2 to 8, characterized in that the intermediate layer (11) of the buffer material (Wp) has a thickness Dp, where: 0.01 mm < Dp < 2 mm, in particular 0.05 mm < Dp < 1.5 mm, and in particular 0.1 mm < Dp < 1 mm.

10. A method for producing a strand producer for producing strands of material, comprising the steps: - Providing a base body (2) and at least one wear protection element (3), - producing an arrangement comprising the base body (2), the at least one wear protection element (3) and at least one brazing material (WH), which is arranged as at least one layer (10, 12) between the base body (2) and the at least one wear protection element (3), - heating and melting of at least one brazing material (WHI, WH2), and - Cooling of the at least one brazing material (WHI, WH2) for connecting the base body (2) to the at least one wear protection element (3).

11. The method according to claim 10, characterized in that a first layer (10) of the at least one brazing material (WHI, WIE), an intermediate layer (11) of a buffer material (Wp) and a second layer (12) of the at least one brazing material (WHI, WH2) are arranged between the base body (2) and the at least one wear protection element (3).

12. A method according to claim 10 or 11, characterized in that the heating is carried out at least to a minimum temperature T m in, where: T m in > 980 °C, especially T m in > 1000 °C, and especially Tmin > 1020 °C.

13. Method according to at least one of claims 10 to 12, characterized in that that heating is limited to a maximum temperature T ma x, where: T ma x < 1070 °C, especially T max< 1050 °C, and in particular T max < 1030 °C.

14. Method according to at least one of claims 11 to 13, characterized in that the buffer material (Wp) has a melting temperature Tp and the at least one brazing material (WHI, WH2) has a melting temperature TH at normal pressure, where: Tp > TH.

15. Method according to claim 14, characterized in that the heating takes place up to a brazing temperature TL, where: TH < T L < TP.

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