Processing element for a processing element shaft of a screw machine, processing element shaft, screw machine and method for manufacturing a processing element - Patents.com

Abstract

To create an improved treatment element for a treatment element shaft of a screw machine, in particular a treatment element being strong and economical.SOLUTION: Treatment elements (6 to 15, and 6' to 15') for treatment element shafts(4 and 4') of a screw machine (1) comprises a main body (36) with an outer wall (40), in which the outer wall (40) has a first wall section (W1) and a second wall section (W2), and the first wall section (W1) is harder than the second wall section (W2).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a processing element for a processing element shaft of a screw machine. Furthermore, the present invention relates to a processing element shaft having a processing element of said type, and to a screw machine having a processing element shaft of said type. The present invention also relates to a method for manufacturing a processing element for a processing element shaft of a screw machine. [Background technology]

[0002] Patent Document 1 discloses a multi-screw machine having a housing body with two housing bores and two processing element shafts arranged in the housing bores. Each processing element shaft has a number of processing elements in the form of screw elements and kneading elements, each with an outer wall for interacting with the plastic material for processing. The processing elements are designed to be tightly intermeshed with each other. The tightly intermeshing design of the processing elements has an effect on their conveying and shearing properties, resulting in an increased tendency for wear to occur. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2018 / 033353A1 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention is based on the object of creating an improved processing element for the processing element shaft of a screw machine, which is particularly robust and economical to operate, and which is also intended in particular to have a positive influence on the material preparation in the screw machine. [Means for solving the problem]

[0005] This object is achieved by a processing element having the features of claim 1. The invention has been achieved by providing a processing element whose body has an outer wall with a first wall portion that is harder than a second wall portion of the outer wall, making the processing element particularly robust and wear-resistant, and thus particularly economical to operate. In particular, the relatively hard shape of the first wall portion ensures reduced wear in the area of ​​the outer wall that interacts with the screw machine housing and / or the outer wall of the processing element of the adjacent processing element shaft in a sealingly interlocking manner. Due to its relatively high hardness, the first wall portion can withstand relatively high loads. The robustness of the processing element is particularly benefited by the fact that the first wall portion is supported by a second wall portion with a relatively lower hardness and is installed in a particularly soft and / or damped manner. The tendency of the processing element to fracture, particularly in the second wall portion, is thereby reduced. The increased wear resistance of the processing element results in greater or more durable dimensional accuracy of the processing element and of the processing element shaft. Material preparation is thus positively affected.

[0006] The outer wall should be understood to mean the wall of the body that comes into contact with the material or substance to be treated. The material to be treated may be a plastic material, in particular a plastic material with additives. The body is preferably formed as a hub with teeth. The body preferably has two connecting walls for interacting with respective adjacent treatment elements of the same treatment element shaft that are non-rotatably connected to the same support shaft. Preferably, the outer wall completely delimits (bounds) the body outward in a radial direction relative to the rotation axis of the treatment elements. The treatment elements are rotatable around the rotation axis for treatment of the substance, in particular can be driven in rotation. The inner wall is preferably formed coaxially with the rotation axis.

[0007] The processing elements may be formed as screw elements and / or kneading elements. They may be of single- or multi-start, especially double- or triple-start, type. The kneading elements may have one or more kneading disks. The screw elements and / or kneading elements are preferably formed as a single piece (monolithically molded).

[0008] Preferably, the first wall portion is formed by a first material layer and the second wall portion is formed by a second material layer. The second material layer is preferably the substrate of the body. The mass of the substrate preferably forms at least 50%, in particular at least 70%, in particular at least 90%, in particular at least 95% of the mass of the processing element. In this way, it is advantageously achieved that the relatively stiff first material layer is supported by the second material layer with low stress, in particular in a damped manner. Steel 1.4112, for example, may be used as the substrate. The layer thickness of the first material layer and / or the second material layer is preferably at least 0.5 mm and at most 5 mm.

[0009] According to one aspect of the invention, the first material layer is connected to the second material layer by a material bond, in particular by welding. The first material layer preferably differs from the second material layer by material composition and / or material structure. The different material compositions are ensured, for example, by the preparation of different metal alloys, in particular by layer build-up welding (build-up welding). The different material structures are obtained, for example, by heat treatment, in particular by laser hardening. The first material layer may, for example, be predominantly in the martensite phase, and the second material layer may be predominantly in the austenite phase. The processing element can thus be produced particularly economically, and in particular the first wall part and the second wall part have a particularly efficient shape.

[0010] The first and / or second layer of material may be different from the substrate, which may be harder and / or softer than the first and / or second wall portion.

[0011] The harder shape of the first wall portion relative to the second wall portion may be achieved by treatment of the substrate and / or by deposition of a material layer on the substrate, which may comprise a heat treatment, in particular a surface hardening treatment, a diffusion hardening treatment (nitriding, carbonitriding), electron beam hardening, laser hardening and / or an induction hardening treatment.

[0012] The hardness of the wall portion is determined, for example, according to the Brinell (HB) method according to DIN EN ISO 6506-1, or the Vickers (HV) method according to DIN EN ISO 6507-1, or the Rockwell (HRC) method according to DIN EN ISO 6508.

[0013] The first material layer, which is applied to the body, preferably by material deposition, to form the at least one first wall portion, preferably comprises at least one material selected from the following materials: in particular cobalt-based alloys based on CoCr (Stellite), NiCrBSi-based alloys, iron-based powder metallurgy tool steels with or without hard material fragments, composite materials consisting of at least one of the above-mentioned materials with additional carbide and / or nitride hard material inclusions, CrN, TiAlN, TiC, WC, CrC, ceramics.

[0014] The second layer of material, which is applied to the body, preferably by layer deposition, to form the second wall portion, preferably comprises at least one material selected from the following materials: high-grade steel, low-alloy steel, nickel-based material, NiCr70Nb, aluminum, brass, bronze, such as aluminum bronze, copper bronze, nickel bronze, Walkeshaw alloy. The first and second layers of material preferably comprise a metal, in particular steel.

[0015] According to one aspect of the invention, the first and / or second wall portions are formed as crack stoppers for preventing crack formation and / or propagation. Preferably, the main extension direction of the first and / or second wall portions is oriented transversely (transversely) to the crack propagation direction, in particular perpendicularly, and / or at an angle in the range of 30° to 60° to the axis of rotation. Preferably, the main extension direction of the first and / or second wall portions is oriented obliquely thereto, in particular perpendicularly to the axis of rotation. Thus, crack formation and propagation are reliably prevented. In particular, the second wall portion is suitable for stopping cracks due to its relatively low hardness.

[0016] According to one aspect of the invention, the first wall portion and / or the second wall portion have a continuous shape, and may be formed in a polygonal, in particular rectangular, in particular square, shape, and / or a circular and / or elliptical shape in plan view.

[0017] The first and / or second wall portion may have a cross-sectional area that is tapered in a direction perpendicular to the outer wall, in particular in the direction of the axis of rotation. The cross-sectional area may have, for example, a triangular, trapezoidal or arcuate shape. Corresponding cross-sections can be easily manufactured. The main extension direction of the first or second wall portion, respectively, is decisive for determining the cross-sectional area. According to one aspect of the invention, the cross-sectional area is oriented perpendicular to the axis of rotation.

[0018] According to one aspect of the invention, the first wall portion protrudes beyond the envelope spanned by the second wall portion. In this way, the first wall portion protrudes beyond the second wall portion perpendicular to the outer wall, in particular radially relative to the axis of rotation. Alternatively, the first and second wall portions may be formed flush with each other. In particular, the first wall portion may coincide with the envelope of the second wall portion.

[0019] The protrusion of the first wall portion relative to the second wall portion perpendicular to the outer wall, in particular in the outward direction, may be formed by wear of the second wall portion during manufacture and / or during operation of the processing element.

[0020] A processing element according to claim 2 is particularly robust and economical to operate. Preferably, the outer wall has a plurality of first wall portions and a plurality of second wall portions. For example, the first wall portions and the second wall portions may be arranged alternately with one another. Preferably, the first wall portions and the second wall portions are oriented parallel to one another, in particular arranged in a thin film. The first wall portions may have geometrically identical or different shapes from one another. The same preferably applies to the second wall portions. Furthermore, the first wall portions may have geometrically identical shapes relative to the second wall portions.

[0021] The treatment element according to claim 3 is particularly wear-resistant. The first wall portion is preferably harder than the second wall portion by at least 50 HV 10, in particular by at least 75 HV 10, in particular by at least 100 HV 10, in particular by at least 150 HV 10, in particular by at least 200 HV 10. Preferably, the first wall portions have the same hardness. The deviation in hardness of the first wall portions is preferably at most 50 HV 10, in particular at most 20 HV 10, in particular at most 10 HV 10. The same preferably applies to the second wall portions.

[0022] The treatment element according to claim 4 is particularly robust in operation. The outer rotation surface of the body is defined by a circumferential surface that is stretched during the complete rotation of the body around the rotation axis. The end faces of the envelope stretched in this way do not belong to the outer rotation surface. The wall section that coincides with the outer rotation surface can contact the inner wall of the housing of the screw machine. Due to the fact that the first, relatively hard wall section is located on, and particularly coincides with, the outer rotation surface of the body, wear caused by contact with the housing is reduced. Depending on the location of the treatment element axis and the gap between the treatment element and the housing, contact between the treatment element and the housing is also prevented. Generally, increased shear loads are then generated in the area between the treatment element and the housing due to the material being treated. Therefore, the arrangement of the first wall section in the area of ​​the outer rotation surface also has the effect of reducing wear in this highly loaded area.

[0023] The processing element according to claim 5 is particularly robust in operation. Depending on whether single-flute or multi-flute processing elements are present, the outer wall may have at least one base section and at least one ridge section. The ridge section refers to that section of the outer wall that is radially farthest from the rotation axis. The outer wall is preferably composed of the at least one base section and the at least one ridge section. Preferably, first wall portions are arranged in both the ridge section and the base section. The processing elements are preferably designed to be sealingly interlocked. Due to the fact that adjacent processing elements of different element axes are sealingly interlocked with each other, the base section is also subjected to high loads, in particular due to sliding friction and / or increased shearing of the material being processed. The arrangement of the at least one first wall portion in the base section makes the processing element particularly robust against corresponding loads. The ridge section is in particular the screw top or kneading element top.

[0024] Claim 1, The processing element according to claim 6 is particularly economical to manufacture and particularly robust in operation. The orientation of the first wall portion and / or the second wall portion parallel to the helix line improves the conveying properties of the screw element. Preferably, a plurality of first wall portions are provided in the crest section of the screw element. The sealing effect between the screw element and the housing is therefore improved. This increases the conveying capacity of the screw element. The formation and / or propagation of cracks transverse to the helix line is therefore prevented. The first wall portion and / or the second wall portion may be arranged transversely, in particular perpendicularly, to the helix line. In this way, the shear effect between the processing element and the housing is improved.

[0025] Claim 1,The processing element according to claim 7 is operationally robust and particularly economical to manufacture. A strip-like shape is understood to mean that the aspect ratio of the first wall portion and / or the second wall portion is at least 5, in particular at least 10, in particular at least 15, in particular at least 20. The aspect ratio is preferably at most 10,000, in particular at most 5000, in particular at most 1000. Preferably, the first wall portion and / or the second wall portion have a constant transverse extent in the direction transverse to their respective main extension direction. In particular, a plurality of first wall portions are arranged alternately with a plurality of second wall portions. The preparation of the substance or material is correspondingly favorably influenced by the thin-film-like arrangement.

[0026] The at least one first wall portion and the at least one second wall portion may be formed to intersect each other, which further improves the crack arresting function of the first wall portion and / or the second wall portion, and also improves the transport and shear properties of the processing element.

[0027] The processing element according to claim 8 is particularly wear-resistant and ensures a good effect on the preparation of the substance to be processed. Preferably, the first and / or second wall portion are oriented parallel and / or perpendicular to the axis of rotation in the region of the outer surface of rotation. In particular, the strip-shaped first wall portion may be oriented parallel to the axis of rotation in the region of the outer surface of rotation. In this way, an advantageous increase in the shearing effect on the substance to be processed and the sealing effect on the housing is achieved. The first and / or second wall portion may also be oriented obliquely to the axis of rotation.

[0028] The treatment element according to claim 9 is particularly wear-resistant. Due to the parallel orientation of the first and second wall portions, in particular of a plurality of alternating first and second wall portions, they are subjected to a particularly uniform load. Load peaks are reduced, which makes the treatment element particularly robust.

[0029] A processing element according to claim 10 is particularly robust in operation and can be manufactured particularly economically. Preferably, the first and / or second wall portion surrounds the axis of rotation over at least 180°, in particular over at least 270°, in particular over at least 360°, in particular over at least 720°. Frictional resistance against the housing and / or against adjacent processing elements is reduced by the guiding action of the first and / or second wall portion. A continuous shape over the corresponding angular range ensures improved transport of the processing substance. Preferably, the first and / or second wall portion in this case has a strip-like shape.

[0030] According to one aspect of the invention, the first and / or second wall portion extend in the conveying direction and / or in the circumferential direction over at least 50%, in particular at least 80%, in particular at least 100% of the extent of the flight (thread pitch) of the screw element and / or of the kneading disk of the kneading element. The first and / or second wall portion may also extend over more than one flight, in particular over more than two flights of the screw element.

[0031] A processing element according to claim 11 can be manufactured particularly economically and is particularly robust in operation. The material deposition can be carried out, for example, by build-up welding and / or by hot isostatic pressing. Preferably, the first wall portion projects beyond the envelope formed by the second wall portion, in particular radially outward with respect to the axis of rotation.

[0032] Furthermore, the first wall portion and / or the second wall portion can be produced by material removal. Material removal can be performed chemically, in particular in an etching process, and / or mechanically, in particular by cutting, in particular by milling. For example, the second wall portion can be formed by material removal. For chemical material removal, those portions where material removal is not performed are preferably first masked. In particular, in this way, the first wall portion can protrude outward beyond the second wall portion, in particular beyond the envelope spanned by the second wall portion.

[0033] The processing element according to claim 12 ensures particularly high conveying and shearing capacities and is operationally robust. To form a grooved outer wall, it preferably comprises a plurality of first wall portions and a plurality of second wall portions. The first wall portion and / or the second wall portion are preferably offset relative to each other with respect to the outer wall. In particular, the first wall portion and / or the second wall portion each deviate from the envelope stretched by the other wall portion. For example, the first wall portion forms a peak section and the second wall portion forms a groove section, or vice versa. In the case of a strip-like shape of the first wall portion and / or the second wall portion, it is possible to provide a surface configured in the shape of a thin film. Alternatively, the outer surface may have a plurality of island-like elevations, preferably in the form of the first wall portions.

[0034] The invention is further based on the object of creating an improved processing element shaft that is particularly economical to operate, particularly wear-resistant and / or has a positive effect on the material preparation.

[0035] This object is achieved by a processing element shaft having the features of claim 13. The advantages of the processing element shaft according to the invention correspond to the advantages of the processing elements described above. In particular, the processing element shaft can be improved using the features of the processing elements. According to one aspect of the invention, the processing element shaft comprises at least one screw element and at least one kneading element. The processing element shaft may also comprise exclusively screw elements or exclusively kneading elements. Preferably, the processing element shaft is designed to interact in a sealingly intermeshing manner with the housing and / or with adjacent processing element shafts. The processing element shaft according to the invention may comprise similar and / or different screw elements and / or kneading elements.

[0036] The invention is further based on the object of creating a screw machine which is particularly economical in operation, in particular which requires little maintenance and / or which has a positive effect on the preparation of the substance.

[0037] This object is achieved by a screw machine having the features of claim 14. The screw machine may be a single-screw machine or a multi-screw machine, in particular a twin-screw machine. The advantages of the screw machine according to the invention correspond to the advantages of the processing element shaft and the advantages of the processing elements described above. In particular, the screw machine can be improved using the features of the processing element shaft and the features of the processing elements. The housing body preferably has multiple housing parts that are reversibly connectable to one another. At least one processing element shaft is preferably designed to be sealingly intermeshed with the housing. In the case of a multi-screw machine, the processing element shafts are preferably designed to be sealingly intermeshed with one another. Furthermore, in the case of a multi-screw machine, the processing element shafts can preferably be driven in rotation in opposite directions.

[0038] According to one aspect of the invention, the screw machine has an intake zone and / or a melting zone and / or a plasticization zone and / or a degassing zone and / or a homogenization zone and / or a conveying and mixing zone and / or a pressure build-up zone, in which at least one processing element according to the invention is arranged.

[0039] The invention is further based on the object of creating an improved method for manufacturing processing elements.

[0040] This object is achieved by a method having the features of claim 15. The advantages of the method according to the invention correspond to the advantages of the screw machine, the advantages of the processing element shaft and the advantages of the processing element described above. In particular, the method can be improved using the features of the screw machine, the features of the processing element shaft and the features of the processing element. The method according to the invention is preferably part of a method for manufacturing a processing element shaft and / or a processing element.

[0041] Further features, advantages and details of the invention will become apparent from the following description of several exemplary embodiments. [Brief explanation of the drawings]

[0042] [Figure 1]1 is a partial cross-sectional side view of a multi-screw machine having a housing and two processing element shafts, each having multiple processing elements. [Figure 2] 2 is a partial cross-sectional plan view of the multi-screw machine in FIG. 1. [Figure 3] 3 is a cross-sectional view through the multi-screw machine along section line III-III in FIG. 2. [Figure 4] 1 is a side view of a processing element in the form of a screw element according to a first exemplary embodiment; FIG. [Figure 5] FIG. 5 is a cross-sectional view of the screw element taken along the line VV in FIG. 4. [Figure 6] FIG. 10 is a side view of a processing element in the form of a screw element according to another exemplary embodiment. [Figure 7] FIG. 7 is a cross-sectional view of the screw element taken along the line VII-VII in FIG. 6. [Figure 8] FIG. 10 is a side view of a processing element in the form of a kneading element according to another exemplary embodiment. [Figure 9] FIG. 9 is a cross-sectional view of the kneading element taken along the cutting line IX-IX in FIG. 8. [Figure 10] FIG. 10 is a side view of a processing element in the form of a kneading element according to another exemplary embodiment. [Figure 11] FIG. 11 is a cross-sectional view of the kneading element taken along the cutting line XI-XI in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0043] A screw machine 1 for preparing a substance or plastic material 2 is described on the basis of figures 1 to 3. The plastic material may have several additives 3. The screw machine 1 is in the form of a multi-screw machine, in particular in the form of a twin-screw machine.

[0044] The screw machine 1 has a first processing element shaft 4 and a second processing element shaft 4'. To distinguish between the components of the first processing element shaft 4 and the second processing element shaft 4', the reference numerals associated with the second processing element shaft 4' include the suffix "'." Along the conveying direction, the processing element shafts 4, 4' each have a number of processing elements 6-15 or 6'-15', respectively, arranged in series. The processing element shafts 4, 4' are rotatably arranged within a housing 16 of the screw machine 1. The housing 16 has a housing body 16a. Two mutually parallel housing bores 17, 17' are arranged in the housing body 16a. The first processing element shaft 4 is arranged in the first housing bore 17, and the second processing element shaft 4' is arranged in the second housing bore 17'. The first housing bore 17 and the second housing bore 17' are oriented parallel to each other and overlap each other so that in cross section they have the shape of a figure eight lying on its side. The processing element shafts 4, 4' are arranged coaxially with respect to the housing bores 17, 17'.

[0045] The first processing element shaft 4 has a first support shaft 18 to which the processing elements 6-15 are attached in a rotationally fixed manner. The second processing element shaft 4' has a second support shaft 18' to which the processing elements 6'-15' are attached in a rotationally fixed manner. The processing element shafts 4, 4' are respectively rotatable about rotation axes 19, 19' oriented parallel to the conveying direction 5. The processing element shafts 4, 4' can be rotationally driven by a drive motor 20. A distributor transmission 21 is arranged between the processing element shafts 4, 4' and the drive motor 20, and a clutch 22 is arranged between the drive motor 20 and the distributor transmission 21. The processing element shafts 4, 4' are driven in the same way, i.e. in the same rotation direction 23, 23' about their respective rotation axes 19, 19'.

[0046] The housing 16 has housing parts 24, 25. A material feed 26 in the form of a funnel is arranged in the first housing part 24 along the conveying direction 5, through which the plastic material 2 for preparation and, if necessary, additives 3 can be introduced into the housing bores 17, 17'.

[0047] The screw machine 1 comprises, successively in the conveying direction 5, an intake zone 27, a melting or plasticizing zone 28, a degassing zone 29, a homogenizing zone 30, a conveying and mixing zone 31, and a pressure build-up zone 32. The housing 16 comprises a nozzle plate 33 which is connected to the final housing section 24 in the conveying direction 5. The nozzle plate 33 comprises a discharge opening 34.

[0048] The processing elements 6, 6', 7, 7', 10, 10', 12, 12', 13, 13', 14, 14', 15, 15' are in the form of screw elements. The processing elements 8, 8', 9, 9', 11, 11' are in the form of kneading elements. The housing parts belonging to the processing elements 6, 6', 7, 7', 10, 10', 12, 12', 13, 13', 14, 14', 15, 15' in the form of screw elements are designated with the reference number 24. The housing part designated with the reference number 25 interacts with the processing elements 8, 8', 9, 9', 11, 11' in the form of kneading elements.

[0049] The kneading elements 8, 8', 9, 9', 11, 11' comprise a number of kneading disks 48 which are arranged angularly offset with respect to one another and successively in the conveying direction 5. The kneading disks 48 arranged adjacent to one another are formed as a one-piece kneading block.

[0050] In the intake zone 27, screw elements 6, 6', 7, 7' are arranged on respective support shafts 18, 18'. The screw elements 6, 6', 7, 7' engage with one another in pairs of tightly intermeshing. In the melting zone 28, kneading elements 8, 8', 9, 9' are arranged on support shafts 18, 18', and the kneading elements are also arranged in pairs of tightly intermeshing. In the following degassing zone 29, screw elements 10, 10' are also arranged on support shafts 18, 18' in a similar manner, in a tightly intermeshing fashion. The housing part 24 belonging to the degassing zone 29 has a degassing opening 35 for degassing the plastic material 2 to be processed. In the following homogenization zone 30, kneading elements 11, 11' are arranged on support shafts 18, 18' in a tightly intermeshing fashion. Furthermore, in the subsequent conveying and mixing zone 31, the screw elements 12, 12', 13, 13', which are tightly intermeshed with one another, are arranged on support shafts 18, 18'. Correspondingly, in the next pressure build-up zone 32, the screw elements 14, 14', 15, 15' are arranged on support shafts 18, 18'. The processing elements 6-15, 6'-15' have, for example, a single- or double-start configuration.

[0051] FIG. 3 shows the screw machine 1 in cross section. Each of the processing elements 6-15, 6'-15' has a body 36. Each body 36 is penetrated by an axial bore 37, 37'. The axial bore 37, 37' has the form of a hub with teeth. To connect the support shaft 18, 18' to the processing element 6-15, 6'-15' in a rotationally fixed manner, the support shaft 18, 18' has a corresponding wave-like profile that interacts with the hub profile of the axial bore 37, 37' in a positively engaging manner. The central longitudinal axis of the axial bore 37, 37' coincides with the central longitudinal axis of the housing bore 17, 17' and the rotation axis 19, 19'. The axial bore 37 is bounded (defined) by an inner wall 38. The body 36 is further defined by a plurality of connecting walls 39 between two adjacent processing elements 6-15, 6'-15' along the conveying direction 5. The body 36 is further defined by an outer wall 40. The outer wall 40 is designed to be in contact with and act on the plastic material 2 .

[0052] The body 36 has a length Lw in the conveying direction 5. The axial bore 37 extends through the entire body 36 in the conveying direction 5, so that the axial bore 37 also has a length Lw. The processing elements 6-15, 6'-15' have an outer diameter Dw. The housing bores 17, 17' have a diameter D G It has.

[0053] The outer walls 40 of both the screw elements and the kneading elements each have one ridge section 41 and one base section 42. In the region of the ridge section 41, the outer walls 40 have an outer diameter Dw. The base section 42 forms a plurality of flanks 43 of the processing elements 6-15, 6'-15'.

[0054] 4 shows the screw element 6 in more detail. The outer wall 40 has a plurality of first wall portions W1 and a plurality of second wall portions W2. The first wall portions W1 have a strip-like shape and extend parallel to the helical line 44 of the screw element 6. Overall, the outer wall 40 has two first wall portions W1. Both wall portions W1 are arranged in the ridge section 41. The second wall portion W2 forms the remaining surface of the outer wall 40. The second wall portion W2 extends over the ridge section 41 and the base section 42.

[0055] The first wall portions W1 have a dimension X1 in the conveying direction 5, perpendicular to their main direction of extension. Along their main direction of extension, the first wall portions W1 have a dimension L1 which corresponds to the length of the spiral line 44. For the ratio L1 / X1, the following formula applies: L1 / X1≧10. The first wall portions W1 correspondingly have a strip-like shape.

[0056] The first wall portion W1 projects radially outward and perpendicular to the outer wall 40 beyond the envelope 45 spanned by the second wall portion W2. In particular, the first wall portion W1 is formed by depositing a layer of material M1, which has a layer thickness D1 in the radial direction relative to the respective rotation axes 19, 19'. Preferably, the layer thickness is at least 1 mm and at most 4 mm.

[0057] The application of the material layer M1 is carried out, for example, by means of at least one of the following material deposition methods: laser welding, PTA welding (PTA: Plasma Transferred Arc), electrode welding, thermal spraying, hot isostatic pressing, sintering, brazing, additive manufacturing, CVD coating (CVD: Chemical Vapour Deposition) and / or PVD coating (PVD: Physical Vapour Deposition), coating by detonation.

[0058] To form the first wall portion W1, at least one material of the first material layer M1 is selected from the following materials: cobalt-based alloys (Stellite), NiCrBSi-based alloys, powder metallurgy tool steels with or without hard material portions and / or based on iron, composite materials consisting of at least one of the above-mentioned materials with additional carbide and / or nitride hard material inclusions, CrN, TiAlN, TiC.

[0059] The second wall portion W2 is formed by the substrate M2 of the body 36. The second wall portion W2 has a layer thickness D2. The substrate M2 is a conventional substrate, for example steel 1.4112. In particular, the material layer M1 is harder than the substrate M2. This ensures that the first wall portion W1 is harder than the second wall portion W2. In particular, the first wall portion W1 is 100 HV 10 harder than the second wall portion W2.

[0060] The outer wall 40 has a groove (profile) 46. The groove 46 is formed so that the first wall portion W1 projects radially relative to the axis of rotation 19 beyond the envelope 45 spanned by the second wall portion W2. In the region of the ridge section 41, the first wall portion W1 thus deviates from the second wall portion W2 in the radial direction relative to the axis of rotation 19. The first wall portion W1 forms a plurality of webs between which extend grooves (channels) in the form of the second wall portion W2. In this way, improved conveying and sealing are achieved.

[0061] Only the first wall portion W1 is on the outer rotation surface 47 of the body 36. The outer rotation surface 47 is defined by an outer envelope stretched in the case of a complete rotation of the respective processing element 6-15, 6'-15' around the rotation axis 19, 19'.

[0062] A screw element according to a further exemplary embodiment will be described with reference to Figures 6 and 7. Unlike the above-described exemplary embodiment, the first wall portion W1, located in the ridge section 41, is oriented parallel to the rotation axis 19. The ratio L1 / X1 is at least 0.5 and at most 10. The first wall portion W1 is again located only in the ridge section 41, while the second wall portion W2 is formed in the ridge section 41 and in the base section 42.

[0063] The first wall portion W1 does not protrude beyond the envelope 45 spanned by the second wall portion W2. Rather, the first wall portion W1 rests on the envelope 45. The second wall portion W2, located in the ridge section 41, is oriented parallel to the first wall portion W1. The outer wall 40, and in particular the ridge section 41, does not have any grooves (contours, profiles).

[0064] The first material layer M1 is formed by hardening the substrate M2, which is carried out, for example, by one of the following hardening methods: surface hardening, nitriding, boriding, laser hardening.

[0065] A further exemplary embodiment will be described with reference to Figures 8 and 9. Unlike the above-described exemplary embodiment, the processing elements 6-15, 6'-15' formed by the first wall portion W1 and the second wall portion W2 are kneading elements 8, 8', 9, 9', 11, 11'. The kneading element 8 has a third wall portion W3 in addition to the first wall portion W1 and the second wall portion W2. The wall portions W1, W2, W3 have a strip-like shape. The main extension direction of the wall portions W1, W2, W3 is oriented obliquely to the rotation axis 19 and obliquely to the cross section of the kneading element 8. The wall portions W1, W2, W3 extend over a ridge section 41 and a base section 42, respectively.

[0066] The third wall portion W3 has a material layer M3, the hardness of which is lower than the hardness of the substrate M2.

[0067] Further exemplary embodiments of the processing elements 6-15, 6'-15' are described on the basis of Figures 10 and 11 using the example of the kneading element 9. In contrast to the exemplary embodiments described above, the ratio between the dimension L1 of each first wall portion W1 along the rotation axis 19 and the dimension X1 of each first wall portion W1 perpendicular to the dimension L1 parallel to the outer wall 40 is at most 5. In particular, the dimension of the first wall portion W1 is at most 5 times the length L of the kneading disc 48 along the conveying direction 5. k The second wall portion W2 has a lattice-like shape. At least some of the first wall portions W1 are completely surrounded by the second wall portion W2. The first wall portion W1 projects radially relative to the axis of rotation 19 beyond the envelope 45 spanned by the second wall portion W2. The outer surface of rotation 47 is spanned only by the first wall portion W1.

[0068] Generally, the formation of the at least one first wall portion W1 and the at least one second wall portion W2 can be carried out by processing the outer wall 40, in particular in a hardening process by heat curing. The at least one first wall portion W1 and the at least one second wall portion W2 come into contact with the plastic material 2 for processing during operation of the screw machine. The layer thickness D1 can be smaller, equal to, or larger than the layer thickness D2 of the second wall portion W2. The layer thickness D2 is preferably larger than the layer thickness D1. The material layers M1, M2 can be processed or worked after deposition. The first wall portions W1 and / or the second wall portions W2 can be identical or different in terms of their geometry and / or hardness and / or material composition. [Explanation of symbols]

[0069] 1. Screw machine 36 Main Unit 40 Exterior Wall W1 1st wall part W2 2nd wall part

Claims

1. a processing element for a processing element shaft of a screw machine (1), having a body (36) with an outer wall (40), The outer wall (40) has a first wall portion (W １ ) and the second wall portion (W ２ ) The first wall portion (W １ ) is the second wall portion (W ２ ) harder, and A processing element, wherein said first wall portion (W 1 ) has a strip-like shape and an aspect ratio of said first wall portion is at least 5, the processing elements (6-15, 6'-15') are formed as screw elements (6, 6', 7, 7', 10, 10', 12-15, 12'-15'), the main direction of extension of said first wall portion (W 1 ) being oriented obliquely with respect to the helix line (44) of said screw elements (6, 6', 7, 7', 10, 10', 12-15, 12'-15'), and / or The processing elements (6-15, 6'-15') are formed as kneading elements (8, 8', 9, 9', 11, 11'), characterized in that the main extension direction of the first wall portion (W 1 ) is oriented obliquely to the rotation axis (19, 19') of the processing elements (6-15, 6'-15') and obliquely to the cross section of the kneading elements (8, 8', 9, 9', 11, 11').

2. A plurality of the first wall portions (W １ ) and a plurality of the second wall portions (W ２ 2. The processing element of claim 1, further comprising:

3. The first wall portion (W １ ) is the second wall portion (W ２ 3. The processing element according to claim 1, wherein the processing element is at least 50 HV 10 harder than the processing element.

4. The first wall portion (W １ 4. The processing element according to claim 1, wherein only the outer surface (47) of rotation of said body (36) is provided.

5. The outer wall (40) has a ridge section (41) and a base section (42), and the first wall portion (W １ ) and / or the second wall portion (W ２ 5. The processing element according to claim 1, wherein a plurality of ridge sections (41) and / or a plurality of base sections (42) are arranged in the ridge section (41) and / or in the base section (42).

6. The processing elements (6-15, 6'-15') are formed as screw elements (6, 6', 7, 7', 10, 10', 12-15, 12'-15'), and the second wall portion (W ２ 6. A processing element according to claim 1, characterized in that the main direction of extension of the screw elements (6, 6', 7, 7', 10, 10', 12-15, 12'-15') is oriented parallel and / or obliquely to the helix line (44) of the screw elements (6, 6', 7, 7', 10, 10', 12-15, 12'-15').

7. The second wall portion (W ２ 7. The processing element according to claim 1, wherein the first and second electrodes have a strip-like shape.

8. The first wall portion (W １ ) and / or the second wall portion (W ２ 8. A processing element according to claim 7, characterized in that the rotation axis (19, 19') of the processing element (6-15, 6'-15') is oriented parallel and / or perpendicular to the rotation axis (19, 19') of the processing element (6-15, 6'-15').

9. The first wall portion (W １ ) and the second wall portion (W ２ 9. A processing element according to claim 7, wherein the first and second electrodes are oriented parallel to one another.

10. The first wall portion (W １ ) and / or the second wall portion (W ２ 10. A processing element according to claim 1, wherein the rotation axis (19, 19') of the processing element (6-15, 6'-15') is surrounded by at least 180°.

11. The first wall portion (W １ ) and / or the second wall portion (W ２ 11. The processing element according to claim 1, wherein the processing element is manufactured by material deposition.

12. The first wall portion (W １ ) and / or the second wall portion (W ２ 12. The processing element according to any one of claims 1 to 11, characterized in that: a groove (46) of said outer wall (40) is formed by a groove (46) of said outer wall (40).

13. at least one processing element (6-15, 6'-15') according to any one of claims 1 to 12, and a support shaft (18, 18') on which said at least one processing element (6-15, 6'-15') is mounted so as not to rotate, The processing element axis having

14. - at least one processing element axis (4, 4') according to claim 13, and - housing (16), A screw machine having The housing comprises: --the housing body (16a), and - a screw machine having at least one housing bore (17, 17') formed in said housing body (16a), said at least one processing element shaft (4, 4') being arranged in at least one section.

15. 13. A method for manufacturing a processing element (6-15, 6'-15') for a processing element shaft (4, 4') of a screw machine (1), the processing element (6-15, 6'-15') being according to any one of claims 1 to 12, comprising: - the body (36) is provided with an outer wall (40), -First wall part (W １ ) is the second wall portion (W ２ ) of the first wall portion (W ) of the outer wall (40) so as to be harder than １ ) and the second wall portion (W ２ ) to form A method having the steps.

Images