Press roller

Abstract

A roller for a roller press has a core formed with axially opposite outer ends, an axially central passage, and axially spaced and radially extending inlet and outlet passages extending radially at the outer ends from the central passage and opening radially outward at an outer surface of the core. A coolable jacket surrounds the core, and respective manifold rings are mounted on outer ends of the core, cover inlet and outlet passages at the end faces of the jacket. Respective L-shaped connecting passages each have an axially extending segment opening into a respective one of the cooling passages of the jacket and a radially extending segment opening into the respective groove.

Claims

1. A roller for a roller press for briquetting, compacting, or grinding granular material, the roller comprising: a core extending along an axis and formed with axially opposite outer ends, an axially central passage, and axially spaced and radially extending inlet and outlet passages extending radially at the outer ends from the central passage and opening radially outward at an outer surface of the core; a coolable jacket attached to and surrounding the core and formed with two axially oppositely directed end faces past which the axial opposite outer ends of the core extend axially, and a plurality of axially extending cooling passages that extend axially between the end faces, that open axially outward at the end faces, and that extend in the jacket radially inward of an outer surface of the jacket and radially outward of an inner surface of the jacket; and respective manifold rings mounted on the outer ends of the core, covering the inlet and outlet passages at the end faces of the jacket, and each formed with an annular and radially inwardly open groove that extends angularly and into which a respective one of the inlet and outlet passages opens and respective L-shaped connecting passages each having an axially extending segment opening into a respective one of the cooling passages of the jacket and a radially extending segment opening into the respective groove, such that coolant can flow from the inlet passage to the groove of one of the manifold rings, then radially and axially through the passages of the one manifold ring to the cooling passages at the respective end face of the jacket, then axially through the cooling passage to the other end face of the jacket, then axially and radially to the groove of the other manifold ring, and thence out the outlet passage without separate piping or corrugated steel tubes.

2. The roller defined in claim 1, wherein the jacket is completely tubular and of one piece.

3. The roller defined in claim 2, wherein the jacket is attached to the core by shrink-fitting.

4. The roller defined in claim 1, wherein the outer surface of the jacket is formed with press formations and/or is provided with a wear protection surface.

5. The roller defined in claim 4, wherein the press formations and/or the wear protection surface is/are produced using powder metallurgy and is/are attached to the jacket by hot isostatic pressing.

6. The roller defined in claim 1, wherein the manifold rings are each completely annular and of one piece.

7. The roller defined in claim 1, further comprising: a pair of seal rings between each of the manifold rings and the jacket and flanking the axially extending segments of the L-shaped passages and another pair of seal rings between each of the manifold rings and the core and flanking the radially inwardly open groove of the manifold ring.

8. The roller defined in claim 1, wherein each manifold ring is formed with a plurality of the grooves that extend through an angle of 90 to 180 and that each communicate with the central passage via a respective inlet or outlet passage.

9. The roller defined in claim 1, further comprising: screws securing the manifold rings detachably to the jacket.

10. The roller defined in claim 1, further comprising: restrictions in at least some of the cooling passages that reduce the flow cross-section thereof by a predetermined amount.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The invention shall be explained in greater detail in the following using drawings that illustrate just one illustrated embodiment.

(2) FIG. 1 is a perspective elevation of an inventive roller;

(3) FIG. 2 is an axial section through the roller of FIG. 1;

(4) FIG. 3 is a simplified axial section (in a different section plane);

(5) FIG. 4 is a partly sectional view of the roller of FIG. 1;

(6) FIG. 5 is a partly sectional and large-scale perspective view through part of the roller of FIG. 1, in a different view.

SPECIFIC DESCRIPTION OF THE INVENTION

(7) FIG. 1 shows a roller for a roller press, in particular for briquetting or compacting and particularly preferably for hot briquetting or hot compacting granular material. Such a roller comprises in its basic structure a core 1 and a jacket 2 attached to the core 1. The core 1 is integral with a shaft 3 that is rotatable in bearings 5 in an unillustrated machine frame. The jacket 2 is formed as a tubular one-piece annular jacket that may be attached to the core 1 for example by heat-shrinking. On its outer surface, the jacket 2 is provided with press formations 4 that may be formed for example as mold cavities for briquetting or compacting. This press formations 4 are shown in large scale in FIG. 1. The jacket 2 is made for example from steel, and the press formations 4 are formed as wear surfaces, for example using powder metallurgy, and are applied to the jacket 2, for example using hot isostatic pressing. In this manner a jacket 2 produced in one piece is produced with integrated formations or mold cavities.

(8) In accordance with the invention, the roller is liquid-cooled, for example water-cooled. To this end, formed in the jacket 2 inward of the jacket outer surface or of the formations 4 is a plurality of cooling passages 6 that extend axially and that are spaced angularly. It may be seen that these axially extending cooling passages 6 are not formed in the core 1, but instead are formed in the jacket 2 so that cooling of the roller surface or the formations 4 is particularly effective. These axially extending cooling passages 6 are connected to an axially extending central passage 8 in the core 1 via radially extending inlet and outlet passages 7. This central passage 8 is connected via a suitable rotary feedthrough to a fluid inlet and outlet device 9 that is positioned laterally on the roller shaft 3.

(9) In accordance with the invention, the cooling medium is distributed via two manifold rings 10 that are connected to the jacket 2, one on each end face. These are separate, completely annular, one-piece manifold rings 10 that may be for example made of steel and that are attached to the ends of the jacket 2. Formed in these manifold rings 10 are one or a plurality of annular passages 11 that extend angularly around the respective manifold rings 10 and that are connected either to the respective radial inlet or outlet passage 7 and on the other hand to the ends of the axially extending cooling passages 6. Consequently the coolant is distributed in a simple manner via these separate manifold rings 10. One of the rings 10 forms a manifold ring via which the fluid is fed in and the other opposing ring similarly forms an output ring. The term manifold ring thus encompasses its input function, as well.

(10) The figures show that the radial inlet and outlet passages 7 on the one hand and the axially extending cooling passages 6 on the other hand are connected to one another solely via the manifold rings 10, without using separate piping or corrugated steel tubes. To this end, the manifold ring 10 is sealed, both axially against the jacket 2 and radially against the core 1 by seals 14 and 15. The manifold rings 10 are each mounted at the radial inlet and outlet passages 7 on the core 1 such that the manifold rings 10 so to speak cover the inlet and outlet passages 7. In this manner nearly the entire roller width may be used for the jacket 2.

(11) The seals 14 and 15 are rings. Two perforated flat seals 14 are provided between each manifold ring 10 and jacket 2, specifically preferably one flat perforated seal 14 per manifold ring 10. Provided between each manifold ring 10 and the core 1 are two respective annular seals that preferably have the same diameter and that flank the respective radial inlet and outlet passage 7. These seals 15 may be for example O-rings.

(12) It may be seen in particular in FIGS. 3 and 4 that the annular passages 11 formed in the manifold rings 10 are connected to the individual cooling passages 6 via a plurality of connecting passages 12 that are formed in the illustrated embodiment as deflection passages 12 that each have one radially extending passage segment 12a and one axially extending passage segment 12b, the radial passage segments 12a being connected to the respective annular passages 11 in a star shape and the axial passage segments 12b opening into the cooling passages 6 that extend from them parallel to the axis.

(13) In the illustrated embodiment, for realizing the annular passages 11, the inner surface of each of the manifold rings 10 is formed with a groove 13 that extend angularly around at least part of the inner surface and that, when the manifold ring 10 is assembled, with the core 1 form the respective annular passages 11. This may be seen for example from FIG. 2 and in particular from FIG. 5. Thus FIG. 5 shows the groove 13 formed in the inner surface of the manifold ring 10, for example by machining. This groove 13, together with the outer surface of the core 1, forms the annular passage 11. FIGS. 3 and 5 show that in these embodiments, the seals 14 and 15 are, respectively, between the manifold rings 10 and the jacket 2 and between the manifold rings 10 and the core 1. FIG. 2 also shows that the manifold rings 10 are secured detachably to the jacket 2, specifically by screws 17. To this end, suitable through going holes, for example bores 16, have been formed in the manifold rings 10, through which the respective screws 17 may be inserted into the jacket. Now it is possible to forego separately attaching the manifold rings 10 to the core 1. It is particularly advantageous that the manifold rings 10 may be used for different purposes regardless of the jacket 2, for example after the jacket 2 is worn.

(14) FIG. 4 also illustrates that not just one single completely annular passage 11 is formed in each manifold ring 10, but instead that two annular passages 11 are formed in the manifold ring 10 and each extends (only) through an angle of 180. Each of these semicircular passages 11 is connected to the central passage 8 via a (single) respective intake/output passage 7. Using two separate semicircular passages and consequently two separate cooling system improves the distribution of coolant. Nevertheless, it is not necessary to add a plurality of radially extending passages to the core so the embodiment can be counted on to be stable.

(15) In principle, there is the need to attain uniformly distributed cooling over the outer surface. This requires that the coolant act uniformly on the individual cooling passages 6 or that the coolant flow uniformly therethrough. If, as shown in the figures, annular passages 11 are used that extend through a large angle, the flow output into the individual cooling passages may not be uniform. Thus there is the possibility that more coolant may flow through some cooling passages 6 than through other cooling passages. In view of this, it may be advantageous, while the roller is being produced or while the jacket and/or manifold rings are being produced, to integrate flow restrictors into individual cooling passages 6 or to allocate flow restrictors to these cooling passages. Simple mechanical reductions in diameter may be used. In terms of production engineering, this may be realized in a simple manner for example in that inserted in or worked into the axial segments 12b of the connecting passages 12 are restrictions that have a smaller diameter than the cooling passages 6. This may be determined in advance for example using trials so that manifold rings are manufactured that are distinguished by improved distribution of the coolant. These restrictions, which may be formed for example as shutters, are not shown in the drawings.

(16) To facilitate assembly, it may be useful to provide assembly indicia 18 on the core and on the manifold rings, for example grooves or other markings that are aligned with one another by rotation.