Housing component for a multi-shaft screw machine and method for the production of a housing component

Abstract

A housing component, for the production of a housing of a multi-shaft screw machine, includes a base body, in which at least two bores interpenetrating each other are configured. The bores extend in a conveying direction through the base body and are limited transversely to the conveying direction by an inner wall. The inner wall configures at least one first wall section and at least one second wall section such that the at least one first wall section is harder than the at least one second wall section. The wall sections, for example, are generated by material application. The housing component allows for a reliable wear protection and a positive influence on the material processing.

Claims

1. A housing component for the production of a housing of a multi-shaft screw machine comprising a base body, at least two boxes, which are configured in the base body and are interpenetrating each other, which extend in a conveying direction through the base body, and which are limited transversely to the conveying direction by an inner wall of the base body, wherein the inner wall configures at least one first wall section and at least one second wall section such that the at least one first wall section is harder than the at least one second wall section, wherein the inner wall is configured in a profiled manner in a sectional view, and wherein the at least two bores have continuously curved uninterrupted bore walls between opposing triangle regions of the inner wall with the at least one first wall section being configured as a separate material layer placed upon said continuously curved uninterrupted bore walls.

2. The housing component according to claim 1, wherein the inner wall configures a plurality of first wall sections and a plurality of second wall sections, which are arranged alternatingly to one another.

3. The housing component according to claim 1, wherein the at least one of the group comprising one first wall section and the at least one second wall section is arranged in the triangle regions of the inner wall.

4. The housing component according to claim 1, wherein the at least one of the group comprising one first wall section and the at least one second wall section is arranged in at least one side region of the inner wall.

5. The housing component according to claim 1, wherein the at least one of the group comprising one first wall section and the at least one second wall section is configured in a strip-shaped manner.

6. The housing component according to claim 1, wherein the at least one of the group comprising one first wall section and the at least one second wall section runs in the direction of the conveying direction.

7. The housing component according to claim 1, wherein the at least one of the group comprising one first wall section and the at least one second wall section runs around at least one central longitudinal axis of the at least two bores.

8. The housing component according to claim 1, wherein the at least one second wall section is configured as a material layer placed upon the continuously curved uninterrupted bore walls.

9. A multi-shaft screw machine comprising a housing, which comprises at least one housing component according to claim 1, at least two housing bores configured in the housing and interpenetrating each other, and at least two treatment element shafts arranged in a pivotable manner in the housing bores.

10. The multi-shaft screw machine according to claim 9, wherein the housing comprises at least two housing components, which are configured identically.

11. The Multi-shaft screw machine according to claim 9, wherein the housing comprises at least two housing components, which are configured differently.

12. The housing component according to claim 1, wherein: each of the at least two boreholes has a central longitudinal axis; the first wall section has an inner surface defining a portion of one of the at least two boreholes, the inner surface of the first wall section is arranged at a first radial distance from the central longitudinal axis of the one of the at least two boreholes; the second wall section has an inner surface defining a portion of the one of the at least two boreholes, the inner surface of the second wall section is arranged at a second radial distance from the central longitudinal axis of the one of the at least two boreholes; the first and second radial distances are different.

13. The housing component according to claim 12, wherein: the first radial distance is shorter than the second radial distance.

14. The housing component according to claim 1, wherein each of said interpenetrating bores have a central longitudinal axis; wherein said first wall sections have a radially outer surface in contact with said continuously curved uninterrupted bore walls, said radially outer surface being arranged at a first radial distance from the respective central longitudinal axis, wherein said second wall sections are arranged at a second radial distance from the respective central longitudinal axis, said first radial distance and said second radial distance being equal, wherein said first wall sections have a radially inner surface being arranged at a third radial distance from the respective central longitudinal axis, said third radial distance being less than said first and said second radial distances.

15. A method for the production of a housing component, including the steps: providing a base body, in which at least two bores interpenetrating each other are configured, wherein the bores extend in a conveying direction through the base body, and the bores are limited transversely to the conveying direction by an inner wall of the base body, configuring at least one first wall section and at least one second wall section of the inner wall such that the at least one first wall section is harder than the at least one second wall section, and configuring the inner wall in a profiled manner in a sectional view by applying at least one separate material layer onto continuously curved uninterrupted bore walls between opposing triangle regions of the inner wall of the at least two bores.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 shows a partially sectioned view of a multi-shaft screw machine with a housing assembled of a plurality of housing components,

(2) FIG. 2 shows a partially sectioned top view onto the multi-shaft screw machine in FIG. 1,

(3) FIG. 3 shows a cross section through the multi-shaft screw machine along the intersection line III-III in FIG. 2,

(4) FIG. 4 shows a view of an inner wall of one of the housing components, according to a first embodiment, in a plane,

(5) FIG. 5 shows a cross section of the housing component in FIG. 5 in a triangle region,

(6) FIG. 6 shows a view of an inner wall of one of the housing components, according to a second embodiment, in a plane,

(7) FIG. 7 shows a view of an inner wall of one of the housing components, according to a third embodiment, in a plane,

(8) FIG. 8 shows a view of an inner wall of one of the housing components, according to a fourth embodiment, in a plane,

(9) FIG. 9 shows a view on an inner wall of one of the housing components, according to a fifth embodiment, in a plane, and

(10) FIG. 10 shows a view of an inner wall of one of the housing components, according to a sixth embodiment, in a plane.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(11) A multi-shaft screw machine 1, for example, serves for processing a plastic material 2, which is provided with additives 3. The multi-shaft screw machine 1 is configured as a two-shaft screw machine.

(12) The screw machine 1 has a housing 4 of a plurality of housing components 6 to 15, arranged one after the other in a conveying direction 5. The housing components 6 to 15 are configured as housing sections. The housing components 6 to 15 are connected to each other in a common manner via flanges, not depicted in further detail, and form the housing 4.

(13) In the housing 4, two housing bores 16, 17 are configured, being parallel to and interpenetrating one another, whose cross section shows the shape of a horizontal figure eight. The housing bores 16, 17 are limited by a housing inner wall 34. In the housing bores 16, 17, two treatment element shafts 18, 19 are arranged in a concentric manner, which are pivotable by a drive motor 20 around corresponding rotation axes 21, 22. Between the treatment element shafts 18, 19 and the drive motor 20, a branch gear 23 is arranged, wherein again between the drive motor 20 and the branch gear 23, a coupling 24 is arranged. The treatment element shafts 18, 19 are driven in the same direction, i.e. in the same directions of rotation 25, 26 around the rotation axes 21, 22.

(14) On the first housing component 6 adjacent to the branch gear 23, a material infeed 33 in the shape of a hopper is arranged, through which the plastic material 2 to be processed and, if applicable, the additives 3 can be fed into the housing bores 16, 17.

(15) The screw machine 1, in the conveying direction 5, consecutively shows a feed area 27, a fusion area or plasticizing area 28, a degassing area 29, a homogenization area 30, a conveying and mixing area 31 and a pressurization area 32. The housing 4, on the last housing component 15, is closed by an orifice plate 35, which has a discharge opening 36.

(16) The treatment element shafts 18, 19 are configured by shafts 37, 38 and treatment elements 39, 40 or 39′, 40′ arranged thereon. The treatment elements 39, 40 arranged on the first shaft 37 and the treatment elements 39′, 40′ arranged on the second shaft 38 correspond to each other, wherein the reference numbers of the treatment elements 39′, 40′ arranged on the second shaft 38 have a ‘ for the sake of distinction. The treatment elements 39, 39’ are configured as screw elements, whereas the treatment elements 40, 40′ are configured as kneading elements. The kneading elements 40, 40′ have kneading disks, arranged at an angular offset after one another and in the direction of the respective rotation axis 25, 26. A plurality of kneading disks arranged after one another, for example, are configured as a one-piece kneading block.

(17) In the feed area 27, screw elements 39, 39′ are arranged adjacent to one another on the shafts 37, 38, gearing into each other and being configured in pairs closely intermeshing. In the fusion area 28, kneading elements 40, 40′ are arranged on the shafts 37, 38, also being configured in pairs closely intermeshing. In the subsequent degassing area 29, again, closely intermeshing screw elements 39, 39′ are arranged on the shafts 37, 38. The corresponding housing component 10 has a degassing opening 41 for degassing. In the subsequent homogenization area 30, closely intermeshing kneading elements 40, 40′ are arranged on the shafts. Further on, in the subsequent conveying and mixing area 31, closely intermeshing screw elements 39, 39′ are arranged on the shafts 37, 38. Correspondingly, in the subsequent pressurization area 32, screw elements 39, 39′ are arranged on the shafts 37, 38. The screw elements 39, 39′ and the kneading elements 40, 40′, for example, are configured in a double-threaded and/or in a triple-threaded manner.

(18) The housing components 6 to 15 each have a base body 42, in which the housing bores 16, 17 are configured in sections. Each one of the housing components 6 to 15 thus has bores, which configure a section of the housing bores 16, 17. The bores of the respective housing component 6 to 15 obtain the reference numbers 16′, 17′ in the following, in order to distinguish them from the housing bores 16, 17. Due to the aligned arrangement of the housing components 6 to 15, the bores 16′, 17′ result in the described housing bores 16, 17. The bores 16′, 17′ each have a central longitudinal axis, which is indicated as 21′, 22′ in the following and which correspond to the central longitudinal axes of the housing bores 16, 17 or the rotation axes 21, 22. The bores 16′, 17′ of the respective housing component 6 to 15 are limited by an inner wall W, which configures a part of the housing inner wall 34. A first section W.sub.1 of the inner wall W limits the first bore 16′, whereas a second section W.sub.2 of the inner wall W limits the second bore 17′ of the respective housing component 6 to 15.

(19) In the conveying direction 5, the base body 42 has a length L.sub.G. The bores 16′, 17′ extend in the conveying direction 5 through the entire base body 42, with the result that the bores 16′, 17′ have the length L.sub.G, as well. The bores 16′, 17′ each have a diameter D.sub.G. The bores 16′, 17′ have an axis-center distance A of the central longitudinal axes 21′, 22′, with the result that the bores 16′, 17′ interpenetrate each other. The bores 16′, 17′ or housing bores 16, 17, interpenetrating each other, configure a penetration plane E.sub.Z and so called triangle regions Z.sub.1 and Z.sub.2. In the penetration plane E.sub.Z, a penetration opening 43 is configured. The triangle regions Z.sub.1, Z.sub.2 are arranged in relation to an axial plane E.sub.A through the central longitudinal axes 21′, 22′, opposite to one another. The triangle regions Z.sub.1, Z.sub.2 extend in the conveying direction 5 along the entire length L.sub.G of the respective housing component 6 to 15. Perpendicular to the penetration plane E.sub.Z or parallel to the axial plane E.sub.A, the triangle regions Z.sub.1, Z.sub.2 have a dimension A.sub.Z. For the dimension A.sub.Z, it is provided by definition that: A.sub.Z=0.2 A, in particular 0.3, in particular 0.4 A, in particular 0.6 A, in particular 0.8 A, and in particular 1.0 A. The triangle regions Z.sub.1, Z.sub.2 are configured symmetrically to the penetration plane E.sub.Z. The dimension A.sub.Z thus is located with one half, respectively, on both sides of the penetration plane E.sub.Z.

(20) The inner wall W of the housing components 6 to 15 further on has side regions S.sub.1 and S.sub.2. The side regions S.sub.1 and S.sub.2 are arranged opposite to the penetration plane E.sub.Z and symmetrically to the axial plane E.sub.A. The side regions S.sub.1 and S.sub.2 extend along the entire length L.sub.G of the respective housing component 6 to 15. The side regions S.sub.1 and S.sub.2 have a dimension A.sub.S, perpendicular to the axial plane E.sub.A or parallel to the penetration plane E.sub.Z. For the dimension A.sub.S, it is provided by definition that: A.sub.S=0.3 D.sub.G, in particular 0.4 D.sub.G, and in particular 0.5 D.sub.G. The side regions S.sub.1 and S.sub.2 are arranged symmetrically to the axial plane E.sub.A. Consequently, the dimension A.sub.S is located with one half on both sides of the axial plane E.sub.A.

(21) FIG. 4 visualizes the inner wall W of the housing component 7 in a plane. In the triangle regions Z.sub.1, Z.sub.2, first wall sections w.sub.1 and second wall sections w.sub.2 are configured alternatingly, wherein the first wall sections w.sub.1 are harder in comparison to the second wall sections w.sub.2. The first wall sections w.sub.1 are configured in a strip-shaped manner and, with their main extension direction, extend in a parallel manner to the conveying direction 5. The first wall sections w.sub.1 have a length x.sub.1 in the conveying direction 5 and perpendicular to the conveying direction 5 have a width y.sub.1. For the ratio x.sub.1/y.sub.1, it is provided that: x.sub.1/y.sub.1≥2, in particular: x.sub.1/y.sub.1≥4, and in particular: x.sub.1/y.sub.1≥10. The length x.sub.1 corresponds to the length L.sub.G.

(22) Accordingly, the second wall sections w.sub.2 are configured in a strip-shaped manner and extend in a parallel manner to the conveying direction 5. The second wall sections w.sub.2 have a length x.sub.2 in the conveying direction 5 and perpendicular to the conveying direction 5 have a width y.sub.2. For the ratio x.sub.2/y.sub.2, it is provided that: x.sub.2/y.sub.2≥2, in particular: x.sub.2/y.sub.2≥4, and in particular: x.sub.2/y.sub.2≥10. The length x.sub.2 corresponds to the length L.sub.G. The first wall sections w.sub.1 and/or the second wall sections w.sub.2 can be configured in an identical and/or different manner.

(23) The first wall sections w.sub.1 are configured by application of a material layer M.sub.1 onto the base body 42. This is visualized in FIG. 5. The material layer M.sub.1, in radial direction to the respective central longitudinal axis 21′, 22′, has a layer thickness D.sub.1, for which it is provided that, for example: 1 mm≤D.sub.1≤4 mm.

(24) The application of the material layer M.sub.1, for example, takes place by at least one of the following application methods: laser welding, PTA welding (PTA: PlasmaTransferredArc), electrode welding, thermal injection, hot isotactic pressing, sintering, soldering, additive production, Chemical Vapor Deposition coating and/or Physical Vapor Deposition coating, case hardening, coating by detonation, nitriding, boriding.

(25) For the configuration of the first wall sections w.sub.1, at least one material is chosen from the following materials:

(26) Cobalt base alloys (stellites), NiCrBSi base alloys, powder metallurgical tool steels with or without hard material portion and with iron basis, composite materials of at least one of the aforementioned raw materials with additional carbide and/or nitride hard material intercalations, CrN, TiAlN, TiC.

(27) The second wall sections w.sub.2 are configured by a basic material M.sub.0 of the base body 42. The basic material M.sub.0 is a common basic raw material, such as for example the raw material 1.4112.

(28) FIG. 6 visualizes the inner wall W of the housing component 8 or 9. The housing components 8, 9 are configured identically. In contrast to the housing component 7, the inner wall W of the housing component 8 or 9, in addition to the wall sections w.sub.1 and w.sub.2 in the triangle regions Z.sub.1, Z.sub.2, also has first wall sections w.sub.1 and second wall sections w.sub.2 in the side regions S.sub.1 and S.sub.2. The first wall sections w.sub.1 and the second wall sections w.sub.2 are configured corresponding to the wall sections w.sub.1 and w.sub.2 in the triangle regions Z.sub.1, Z.sub.2. The wall sections w.sub.1, w.sub.2 in the side regions S.sub.1, S.sub.2 differ in comparison to the wall sections w.sub.1, w.sub.2 in the triangle regions Z.sub.1, Z.sub.2 merely in terms of number. With regard to the further configuration, reference is made to the preceding embodiment.

(29) FIG. 7 visualizes the inner wall W of the housing components 10, 11. The housing components 10, 11, accordingly, are configured identically, except for the degassing opening 41. In contrast to the housing components 7 to 9, the entire inner wall W has alternating first wall sections w.sub.1 and second wall sections w.sub.2. The wall sections w.sub.1, w.sub.2 are configured according to the preceding embodiments. With regard to the further configuration, reference is made to the preceding embodiments.

(30) FIG. 8 visualizes the inner wall W of the housing components 12, 13. In contrast to the preceding embodiments, the second wall sections w.sub.2, with their main extension direction, extend perpendicularly to the conveying direction 5. The second wall sections w.sub.2 are arranged in rows oriented in a parallel manner and perpendicularly to the conveying direction 5. The second wall sections w.sub.2 are distributed over the entire inner wall W. Due to the arrangement of the second wall sections w.sub.2, first wall sections w.sub.1 configure, which run in a parallel manner to the conveying direction 5 and extend along the entire length L.sub.G of the housing components 12, 13. Further on, first wall sections w.sub.1 configure, which run perpendicularly to the conveying direction 5 around the central longitudinal axes 21′, 22′, and which cross the first wall sections w.sub.1 running in a parallel manner to the conveying direction 5. The first wall sections w.sub.1 thus form a grid. With regard to the further configuration, reference is made to the preceding embodiments.

(31) FIG. 9 visualizes the inner wall W of the housing components 14, 15. In contrast to the preceding embodiments, the first wall sections w.sub.1 run with a positive grade in the conveying direction 5, at the first section W.sub.1 of the inner wall W around the central longitudinal axis 21′ and at the second section W.sub.2 of the inner wall W around the central longitudinal axis 22′. The second wall sections w.sub.2 run accordingly between the corresponding first wall sections w.sub.1. Alternatively or additionally, the wall sections w.sub.1, w.sub.2 may run with a negative grade in the conveying direction 5. The wall sections w.sub.1 and w.sub.2 thus run spirally with a positive grade and/or with a negative grade in relation to the directions of rotation 25, 26. The penetration opening 43 interrupts the spiral course. With regard to the further configuration, reference is made to the preceding embodiments.

(32) FIG. 10 shows another embodiment. In contrast to the preceding embodiments, the base body 42 on the inner wall W is treated, with the result that a basic layer G is configured. The basic layer G, for example, is configured by a thermal treatment and is hardened, in comparison to the basic material M.sub.0. Subsequently, the first wall sections w.sub.1 and the second wall sections w.sub.2 are configured by material application of material layers M.sub.1 and M.sub.2.

(33) The second wall sections w.sub.2 have a layer thickness D.sub.2 in the direction of the respective central longitudinal axis 21′, 22′, which, for example, corresponds to the layer thickness D.sub.1. The configuration of at least one basic layer G and the configuration of the first wall sections w.sub.1 by means of material application and/or of the second wall sections w.sub.2 by means of material application can be combined randomly. The material layer M.sub.2, in particular, comprises at least one material chosen from the materials:

(34) High-grade steels, low-alloy steels, nickel-based raw materials, NiCr70Nb, aluminum, brass, bronzes, such as for example Al bronzes, Cu bronzes or Ni bronzes, Waukesha alloys.

(35) With regard to the further configuration, reference is made to the preceding embodiments.

(36) In further embodiments, the first wall sections w.sub.1, alternatively or additionally, can be configured by a local surface hardening of the inner wall W. The local surface hardening, for example, takes place by electron-beam or laser hardening. The second wall sections w.sub.2, for example, are configured by the basic material M.sub.0 of the base body 42.

(37) The housing components 7 to 15 can also be configured as bushings, which have at least one first wall section w.sub.1 and at least one second wall section w.sub.2 in the described manner. The bushings, for example, are connected with a housing base body, with the result that they form a respective housing section.

(38) In general, the following is provided:

(39) The configuration of the at least one first wall section w.sub.1 and of the at least one second wall section w.sub.2 can takes place by treatment of the inner wall W and/or by material application. The at least one first wall section w.sub.1 and the at least one second wall section w.sub.2, during the operation of the screw machine 1, have contact with the plastic material 2 to be processed. The layer thickness D.sub.1 can be smaller, equal to or larger than the layer thickness D.sub.2. Preferably, the layer thickness D.sub.2 is larger than the layer thickness D.sub.1. The material layers M.sub.1, M.sub.2 can be treated or processed after the application. A plurality of first wall sections w.sub.1 can be configured identically and/or differently. A plurality of second wall sections w.sub.2 can be configured identically and/or differently.