AU2020230232A1 - A Grinding Assembly and a Roller Assembly - Google Patents

Abstract

The present invention provides a roller assembly (11). The roller assembly comprises a roller body (14) which provides an outer face (15). The outer face extends between a first and second lateral face (17) of the roller body. Each lateral face of the roller body supports a side flange assembly comprising a plurality of side bodies (21) secured to the first lateral face and the second lateral face, wherein each side body extends beyond the outer face of the roller body and are spaced such that a further roller assembly is receivable therebetween. 1/3 2-1 Figure 1 4 3 Figure 2

Description

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Figure 1

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Figure 2

A Grinding Assembly and a Roller Assembly

Field of the Invention

[0001] This invention relates to a grinding assembly and a roller assembly for use in the grinding of materials.

Background

[0002] The following discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application.

[0003] There is a variety of different crushing equipment available to crush ore from its mined size to a size which enables transportation and processing. One form of crusher uses a grinding assembly comprising two counter rotating, high pressure grinding roller assemblies supported in a side by side relationship. Typically, at least one of these rollers is mounted such that it is able to move away from the other roller a predetermined amount. The two rollers define a crushing zone/nip therebetween which receives the ore.

[0004] It is characteristic of high pressure grinding rollers that a portion of the grinding surface of the roller is covered with a layer of rock material which has been previously ground and which is retained on the grinding surface. The purpose of such a layer is to protect and therefore minimise wear upon the grinding surface. To assist in the retention of this rock material the grinding surface of the roller is provided with wear resistant elements at spaced locations. These elements are typically in the form of inserts which are embedded in the roller. During operation the gaps between and/or provided by the inserts fill with the material which has been comminuted by the roller assembly. The material builds up to form a layer around the roller. This layer provides protection to the outer face of the roller and typically remains in place during the grinding action.

[0005] The provision of inserts in the roller surface provides a means by which protection of the grinding surface of the roller may be enhanced. However, it does not necessarily provide adequate protection to the edge and side faces of the roller which are also exposed to the harsh environment. In practice it is often the case that the condition of the roller's working surface is relatively sound while the edges have substantially degraded, therefore limiting the life of the roller.

[0006] During operation of a grinding assembly, ore is fed between the rollers where it forms a material bed in which the particles will be crushed by applying sufficient pressure through the rollers. While most of this action takes place between the outer surfaces of the two rollers, ore does travel to the outer ends of the rollers. While cheek plates are positioned near these ends to restrict the ore leaving the crushing zone, ore nevertheless travels to and spills from the ends. This ore causes wear and damage at the outer ends of the roller as well as the sides of the rollers. These areas, once damaged, can be very difficult to repair and, if left without repair, can result in the need to replace the whole roller.

Disclosure of the Invention

[0007] It is an object of this invention to provide a roller and a roller assembly which ameliorates, mitigates or overcomes, at least one disadvantage of the prior art, or which will at least provides the public with a practical choice.

[0008] Accordingly the invention resides in a grinding assembly for the grinding of materials, the grinding assembly comprises a first roller assembly and a second roller assembly, each roller assembly comprises a roller having a roller body which provides an outer face, the outer face extends between two lateral faces of the roller body, each lateral face of the first roller assembly supports a side flange assembly, the side flange assembly comprises: a plurality of side bodies adapted to be releasably secured to the lateral face of the first roller, each side body has a first end portion which extends radially above the outer surface of the first roller body, the first end portion provides an inner face which is spaced outwardly from the lateral face of the roller body whereby the distance between the inner face of the side bodies, when secured to one lateral face of the first roller body, and the inner face of the side bodies when secured to the other lateral face of the first roller body is greater than the width of the second roller assembly such that, when the grinding assembly is assembled, the second roller assembly is received between the inner faces of the side bodies of the first roller.

[0009] Accordingly the invention resides in a grinding assembly for the grinding of materials, the grinding assembly comprises a first roller assembly and a second roller assembly, the first roller assembly comprises a roller having a roller body which provides an outer face, the outer face extends between two lateral faces of the roller body, each lateral face of the first roller assembly supports a side flange assembly, the side flange assembly comprises:

a plurality of side bodies each having a first end portion which extends radially above the outer face of the roller body, wherein the first end portions of the plurality of side bodies when secured to one of the lateral faces of the roller body are spaced from the first end portions of the plurality of side bodies when secured to the other lateral face of the roller body such that the second roller assembly may be received therebetween.

[0010] Accordingly the invention resides in a grinding assembly for the grinding of materials, the grinding assembly comprises a first roller assembly and a second roller assembly, the first roller assembly comprises a roller body which provides an outer face, the outer face extends between a first lateral face and a second lateral face of the roller body, wherein a first plurality of side bodies is secured to the first lateral face and a second plurality of side bodies is secured to the second lateral face, at least one side body secured to each lateral face has an end portion which extends beyond the outer face of the roller body, whereby the distance between the end portions of the first plurality of side bodies and the second plurality of side bodies is sufficient to receive the second roller assembly therebetween.

[0011]Accordingly the invention resides in a roller assembly, the roller assembly comprises a roller body which provides an outer face, the outer face extends between a first lateral face and a second lateral face of the roller body, each lateral face of the roller body supports a side flange assembly, the side flange assembly comprises:

a first plurality of side bodies secured to the first lateral face and a second plurality of side bodies secured to the second lateral face, wherein each side body extends beyond the outer face of the roller body and are spaced such that a further roller assembly may be received therebetween.

[0012] Preferably each lateral face presents a substantially planar surface. Each lateral face may extend from the outer face of the roller body to or adjacent to a central bore of the roller body through which a shaft is inserted. Each lateral face may incorporate a plurality of holes therein for receiving fastening means. Each lateral face may incorporate an annular indent spaced a distance from the outer face.

[0013] Each of the plurality of side bodies may be secured to the lateral face using the fastening means. The fastening means may be in the form of one or more bolts which pass through a respective hole in the side body and are threadingly received in the respective hole in the lateral face. Preferably each side body has a bolt which passes through a second end portion of the side body. Preferably each side body has a bolt which passes through an intermediate portion of the side body, the intermediate portion being positioned between the first end portion and the second end portion of the side body. When the side body is secured to the respective lateral face, the second end portion may terminate a distance from the end of the lateral face distal the outer face of the roller body.

[0014] Preferably the surfaces of the first end portion which may be exposed to wear during operation have harder properties than the surfaces not exposed to wear. Preferably the surfaces of the first end portion which may be exposed to wear during operation comprise hard bodies.

[0015] The first end portion may provide an inner face which is spaced outward, relative to the roller body, from a side surface of the side body, the side surface abutting the lateral face of the roller body when the side body is secured thereto. The inner face may extend along or parallel to a longitudinal extent of the side body.

[0016] The first end portion of the side body may provide an outer surface which is adjacent the outer surface of the roller body when the side body is secured thereto. The outer face of the first end portion of the side body may align with the outer surface of the roller body to present an extension of the outer face of the roller body. The outer face of the first end portion of the side body may be substantially flush with the outer surface of the roller body to present an extension of the outer face of the roller body. In other embodiments the outer face of the first end portion may be positioned to be lower or higher than the outer face of the roller body.

[0017] The second end portion may incorporate a projection which extends from the side surface of the side body, the side surface abutting the lateral face of the roller body when the side body is secured thereto. The projection may be adapted to be received in the annular indent of the lateral face when the side body is secured to the respective lateral face. The projection may transfer loads exerted on the side body during operation. In an alternative form the lateral face may provide an annular projection, or a number thereof, while the side bodies provide a complementary indent for receiving the annular projection of the lateral face when fitted thereto.

[0018] Preferably the roller assembly comprises a plurality of hard bodies embedded or otherwise secured to or in the outer face of the roller body.

[0019] In alternative embodiments, not all the first end portions of the side bodies of the roller assembly extend above the outer surface of the roller body.

[0020] Accordingly the invention resides in a grinding assembly used for the grinding of materials, the grinding assembly comprising a first roller assembly which comprises a roller body having an outer face, the outer face extending between two lateral faces, each lateral face releasably supports a plurality of side bodies whereby, when fitted, an engagement surface of each side body abuts the lateral face, each side body comprises:

a first end portion which terminates at a position above the roller's outer face when fitted thereto, the first end portion providing an inner face which is substantially perpendicular to the axis of rotation of the roller assembly and spaced a distance from an outer edge of the outer face of the roller body,

wherein a second roller assembly may be received between respective inner faces of the side bodies.

[0021] In the present invention the lateral face portion extending between the outer face and the bore of the roller body, or terminating adjacent thereto, may be substantially planar.

[0022] Preferably the side bodies comprise a second end portion which terminates at or adjacent a bore opening of the roller body;

[0023] Accordingly the invention resides in a roller assembly for the grinding of materials, the roller assembly having an outer face on a roller body, the outer face extending between two lateral faces, each lateral face being substantially planar, each junction of the respective lateral face with the outer face providing an edge portion, the roller assembly comprising:

a plurality of side bodies adapted to be releasably secured to each lateral face of the roller whereby, when fitted, an inner surface of each side body abuts the lateral face, each side body comprises:

a first end portion which terminates at a position above the roller's outer face when fitted thereto, the first end portion providing an inner face, the inner face being spaced outwardly relative to the inner surface of the side body, wherein a second roller assembly may be received between the inner faces of the side bodies when the side bodies are secured to each lateral face of the roller body.

[0024] Preferably the first end portion comprises a plurality of hard bodies to protect the first end portion from wear.

[0025] Accordingly the invention resides in a pressure roller assembly for use in the grinding of materials, the roller assembly having a cylindrical outer face defined between two lateral face portions, each lateral face portion being substantially planar, each lateral face portion co-operating with a plurality of replaceable side bodies secured thereto, each side body having at least a portion thereof in abutment with its respective lateral face portion, wherein one or more of the side plates has a first end portion which extends above the outer face of the roller body.

[0026] Accordingly the invention resides in an roller assembly for a pressure roller used in the grinding of materials, the roller having an outer face on a roller body, the outer face extending between two lateral face portions, each lateral face portion providing a substantially planar surface, the roller assembly comprising: a plurality of side bodies adapted to be releasably secured to the lateral face portions of the roller, whereby when fitted at least a portion of an inner surface of each side body abuts the lateral face portion, one or more or each of the side bodies comprises a first end portion which terminates at a position above the roller's outer face when fitted thereto, the first end portion presenting an inner face which is spaced outwardly relative to the lateral face portion, wherein a second roller assembly may be received between the inner faces of each set of side bodies when they are secured to the respective lateral face portions of the roller body.

[0027]The present invention minimises the likelihood of ore spilling outside the crushing zone/nip and over the ends of the roller. It also results in a flattened pressure distribution curve leading to more even wear on the outer face of the roller. This in turn increases the net output and extends the service life of the roller longer tyre life. Another advantage when compared to conventional prior art rollers is that there is a reduction in specific energy consumption.

[0028] Each side body may be secured to the lateral face by bolting the side body through the lateral face portion and into the roller body. Each side body may be secured to the lateral face portion using other known means, these variations being included within the scope of this invention.

[0029] In one embodiment of the invention one or more of the side bodies may have an aperture therethrough in a region adjacent a second end portion of each side body. Preferably the aperture passes through the enlarged portion. The aperture may be threaded. The threaded aperture may be adapted to receive a threaded fastener which is adapted to assist with removing the side body from the roller. In practice the roller assembly is exposed to harsh environments wherein the material builds up on the side of the rollers, entering any small recess and opening. When this build-up of material hardens it becomes difficult to remove the side bodies when required. To assist in removing the side bodies a fastener may be placed in the threaded aperture. Once the bolt(s) securing the side body in place has been removed or loosened, the threaded fastener may be placed in the threaded aperture and rotated. Eventually the end of the threaded fastener engages the later face of the roller. Further rotation of the threaded fastener causes the second end of the side body to be levered away from the roller, enabling removal of the side body.

[0030] In one variation the lateral face portion of the roller may have a plurality of threaded holes extending into the roller. These threaded holes may align with the aperture of each side body when the side bodies are in position. When fitting a side body relative to the roller a fastener may be placed through the aperture in the side body and into the roller to assist in securing the side body to the roller. The roller may have less threaded holes then there are apertures. In such an arrangement side bodies may be fitted in those positions which correspond with threaded holes in the roller. This assists in installation/replacement of the side bodies.

[0031] In an alternative embodiment, each side body may have at least one protrusion extending therefrom, such that when the side body is secured to the lateral face of the roller the protrusion is received in a recess in the lateral face.

[0032] Preferably an outer face of the first end portion of the side bodies provides an extension to the outer surface of the roller.

[0033] Accordingly the invention resides in an ore grinding mill incorporating a pair of roller assemblies, wherein one of those roller assemblies is as herein described, the rollers being supported in parallel spaced apart relationship and driven in contra-rotation so as in use to grind ore fed between the rollers.

[0034] The position of the central axis of each roller assembly may be fixed relative to each other.

Brief Description of the Drawings

[0035] The invention will be better understood by reference to the following description of a specific embodiment thereof as shown in the accompanying drawings in which:

Figure 1 is a perspective view of a grinding assembly according to a first embodiment of the present invention;

Figure 2 is a side view of a first roller assembly shown in figure 1;

Figure 3 is a cross sectional view of the roller assembly shown in figure 2;

Figure 4 is a cross sectional view of section B identified in figure 3; and

Figure 5 is a perspective view of a side body which is adapted to be attached to the first roller assembly shown in figure 1.

[0036] In the drawings like structures are referred to by like numerals throughout the several views. The drawings shown are not necessarily to scale, with emphasis instead generally being placed upon illustrating the principles of the present invention.

Detailed Description of the Specific Embodiment

[0037] A first embodiment of the invention is depicted in figures 1 to 5. The embodiment of the invention depicted in the figures is designed to enhance the longevity of a grinding assembly 10 and to improve the crushing action resulting in ore having a greater uniformity in size.

[0038] The grinding assembly 10 of the present embodiment is intended for use in the high pressure, grinding of material and comprises a first roller assembly 11, and a second roller assembly 13. In high pressure grinding it is highly desirable for ground ore material to be retained on the outer face of the roller to effect at least part of the grinding action, in addition to providing a degree of protection to the outer face of the roller.

[0039] Each roller assembly 11, 13 is provided with roller body 14 having a cylindrical outer face 15 extending between two, substantially planar, lateral faces 17, whereby an edge portion 19 is provided at the junction of each lateral face with the outer face.

[0040] The outer face 15 of each roller assembly 11, 13 has a number of pockets formed therein so as to receive a hardened insert 21 (only a small section is shown in figure 1). The configuration of each roller assembly's outer face 15 is such that it assists in the formation of a layer of protective material once the grinding action commences.

[0041]The first roller assembly 11 comprises a plurality of side bodies 21 releasably secured to each lateral face 17.

[0042] Referring to figure 5, each side body 21 comprises a first end portion 23, an intermediate portion 24 and a second end portion 25.

[0043] The first end portion 23 provides an inner face 27 and an outer face 29. In this embodiment the first end portion incorporates hard bodies 30 in the form of carbides which are brazed thereon. These hard bodies 30 protect the first end portion from wear. The hard bodies provide the inner face 27 and the outer face 29 of the first end portion 23.

[0044] The inner face 27 is substantially perpendicular to the axis of rotation of the first roller assembly 11.

[0045] The outer face 29 of the first end portion 23 is in the same orientation as the outer face 15 of the roller body 14 so as to form an extension therefrom, as best shown in figure 4. In this embodiment the outer face 29 of the first end portion 23 is below the outer face 15 of the roller body 14. This allows material to build up therein to assist in protecting the first end portion from wear. In other embodiments the outer face 29 of the first end portion 23 may be flush with, or above the outer face 15 of the roller body 14.

[0046] The first end portion 23 comprises a plate section 31 which is thinner than the intermediate portion 24 and the second end portion 23 of the side body 21, as best shown in figure 5. This difference in thickness creates a shoulder 37.

[0047] Each side body has an outer surface 35 and an inner surface 36. The inner surface abuts the lateral face 17 of the roller body 14 when the side body 21 is secured thereto. The outer surface 35 of the side body 21 incorporates the outer surface 33 of the plate section 31.

[0048] The side body 21 also incorporates three holes 39, one hole located through the second end portion 25 and two holes located through the intermediate portion 24. These holes align with corresponding threaded holes 41 which pass through the lateral face 17 into the roller body 14. When securing the side bodies 21 to each lateral face the holes 39, 41 are caused to align before a bolt 43 is placed therethrough and fastened. This releasably fastens the side bodies 21 in position.

[0049] Once the side bodies 21 are secured to the respective lateral face 17, the first end portion 23 terminates at a position radially above the outer face 15 of the roller body 14 (as best shown in figure 3).

[0050] In this embodiment each one of the side bodies 21 secured to each lateral face 17 has its first end portion 23 terminating at a position radially above the outer face 15. These first end portions 23 co-operate to form a flange 44 which extends around and outwardly from the roller body 14. An inner surface 45 of the flange 44 is formed by the co-operation of the inner face 27 of each first end portion 23.

[0051]As noted in figure 3, the distance 'A' between the inner surface 45a of the flange 44a at one lateral face 17a of the roller body 14 and the inner surface 45b of the flange 44b at the other lateral face 17b is greater than the width of the roller body 14. As shown in figure 1 the distance A is sufficient such that when the grinding assembly is assembled, the second roller assembly 13 can be received between flanges 44a and 44b.

[0052] During operation the ore is delivered to the crushing zone/nip between the two roller assemblies 11, 13. As the ore is processed the ore spreads across the outer face of each roller assembly. However, due to the flange at each end more ore remains within the crushing zone rather than spilling from the edge of the roller body.

[0053] During operation if one or more side bodies 21 require repair/replacement, an operator simply removes and repairs/replaces the side bodies 21.

[0054] In the present embodiment each side body 21 is narrow. While this increases the number of side bodies required, it reduces the weight of each side body 21, ensuring the removal and replacement of damaged side bodies can be conducted in a safe manner, and renders these activities easier to complete in the field.

[0055] In other embodiments there may be one, two or more side bodies on each lateral face.

[0056] This design dramatically extends the life and tonnage of the roller body.

[0057] Modifications and variations such as would be apparent to the skilled addressee are considered to fall within the scope of the present invention. The present invention is not to be limited in scope by any of the specific embodiments described herein. These embodiments are intended for the purpose of exemplification only. Functionally equivalent products, formulations and methods are clearly within the scope of the invention as described herein.

[0058] The present invention is not to be limited in scope by the specific embodiment described herein. The embodiment is intended for the purpose of exemplification only. Functionally equivalent products, elements and methods are clearly within the scope of the invention as described herein.

[0059] The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprise", "comprises," "comprising," "including," and "having," or variations thereof are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

[0060] Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0061] Spatially relative terms, such as "inner," "outer," "beneath", "below", "lower", "above", "upper" and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the example term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Claims (38)

1. Claims 1. A grinding assembly for the grinding of materials, the grinding assembly comprises a first roller assembly and a second roller assembly, each roller assembly comprises a roller having a roller body which provides an outer face, the outer face extends between two lateral faces of the roller body, each lateral face of the first roller assembly supports a side flange assembly, the side flange assembly comprises:

   a plurality of side bodies adapted to be releasably secured to the lateral face of the first roller, each side body has a first end portion which extends radially above the outer surface of the first roller body, the first end portion provides an inner face which is spaced outwardly from the lateral face of the roller body whereby the distance between the inner face of the side bodies, when secured to one lateral face of the first roller body, and the inner face of the side bodies when secured to the other lateral face of the first roller body is greater than the width of the second roller assembly such that, when the grinding assembly is assembled, the second roller assembly is received between the inner faces of the side bodies of the first roller.
2. 2. A grinding assembly for the grinding of materials, the grinding assembly comprises a first roller assembly and a second roller assembly, the first roller assembly comprises a roller having a roller body which provides an outer face, the outer face extends between two lateral faces of the roller body, each lateral face of the first roller assembly supports a side flange assembly, the side flange assembly comprises:

   a plurality of side bodies each having a first end portion which extends radially above the outer face of the roller body, wherein the first end portions of the plurality of side bodies when secured to one of the lateral faces of the roller body are spaced from the first end portions of the plurality of side bodies when secured to the other lateral face of the roller body such that the second roller assembly is receivable therebetween.
3. 3. A grinding assembly for the grinding of materials, the grinding assembly comprises a first roller assembly and a second roller assembly, the first roller assembly comprises a roller body which provides an outer face, the outer face extends between a first lateral face and a second lateral face of the roller body, wherein a first plurality of side bodies is secured to the first lateral face and a second plurality of side bodies is secured to the second lateral face, at least one side body secured to each lateral face has an end portion which extends beyond the outer face of the roller body, whereby the distance between the end portions of the first plurality of side bodies and the second plurality of side bodies is sufficient to receive the second roller assembly therebetween.
4. 4. A roller assembly, the roller assembly comprises a roller body which provides an outer face, the outer face extends between a first lateral face and a second lateral face of the roller body, each lateral face of the roller body supports a side flange assembly, the side flange assembly comprises:

   a first plurality of side bodies secured to the first lateral face and a second plurality of side bodies secured to the second lateral face, wherein each side body extends beyond the outer face of the roller body and are spaced such that a further roller assembly is receivable therebetween.
5. 5. The roller assembly according to claim 4 wherein each lateral face presents a substantially planar surface.
6. 6. The roller assembly according to claim 5 where each lateral face extends from the outer face of the roller body to or adjacent to a central bore of the roller body through which a shaft is inserted.
7. 7. The roller assembly according to claim 5 or 6 wherein each lateral face incorporates a plurality of holes therein for receiving fastening means.
8. 8. The roller assembly according to claim 5, 6 or 7 wherein each lateral face incorporates an annular indent spaced a distance from the outer face.
9. 9. The roller assembly according to any one of claims 5 to 8 wherein each of the plurality of side bodies is secured to the lateral face using the fastening means.
10. 10. The roller assembly according to claim 9 wherein the fastening means is in the form of one or more bolts which pass through a respective hole in the side body and are threadingly received in the respective hole in the lateral face.
11. 11. The roller assembly according to claim 10 wherein each side body has a bolt which passes through a second end portion of the side body.
12. 12. The roller assembly according to claim 10 or 11 wherein each side body has a bolt which passes through an intermediate portion of the side body, the intermediate portion being positioned between a first end portion and the second end portion of the side body.
13. 13. The roller assembly according to any one of claims 9 to 12 wherein the second end portion terminates a distance from the end of the lateral face distal the outer face of the roller body when the side body is secured to the respective lateral face,.
14. 14. The roller assembly according to any one of claims 9 to 13 wherein the surfaces of the first end portion which are exposed to wear during operation have harder properties than the surfaces not exposed to wear, and/or the surfaces of the first end portion which are exposed to wear during operation comprise hard bodies.
15. 15. The roller assembly according to any one of claims 9 to 14 wherein the first end portion provides an inner face which is spaced outward, relative to the roller body, from a side surface of the side body, the side surface abutting the lateral face of the roller body when the side body is secured thereto.
16. 16. The roller assembly according to claim 15 wherein the inner face extends along or parallel to a longitudinal extent of the side body.
17. 17. The roller assembly according to any one of claims 9 to 16 wherein the first end portion of the side body provides an outer surface which is adjacent the outer surface of the roller body when the side body is secured thereto, the outer face of the first end portion of the side body aligns with the outer surface of the roller body to present an extension of the outer face of the roller body.
18. 18. The roller assembly according to claim 17 wherein the outer face of the first end portion of the side body is substantially flush with the outer surface of the roller body to present an extension of the outer face of the roller body, or the outer face of the first end portion is positioned to be lower or higher than the outer face of the roller body.
19. 19. The roller assembly according to any one of claims 11 to 18 wherein the second end portion incorporates a projection which extends from the side surface of the side body, the side surface abutting the lateral face of the roller body when the side body is secured thereto.
20. 20. The roller assembly according to claim 19 wherein the projection is adapted to be received in the annular indent of the lateral face when the side body is secured to the respective lateral face, or the lateral face provides an annular projection, or a number thereof, while the side bodies provide a complementary indent for receiving the annular projection of the lateral face when fitted thereto.
21. 21. The roller assembly according to any one of claims 4 to 20 further comprising a plurality of hard bodies embedded or otherwise secured to or in the outer face of the roller body.
22. 22. The roller assembly according to any one of claims 9 to 21 wherein only some of the first end portions of the side bodies of the roller assembly extend above the outer surface of the roller body.
23. 23. A grinding assembly used for the grinding of materials, the grinding assembly comprising a first roller assembly which comprises a roller body having an outer face, the outer face extending between two lateral faces, each lateral face releasably supports a plurality of side bodies whereby, when fitted, an engagement surface of each side body abuts the lateral face, each side body comprises: a first end portion which terminates at a position above the roller's outer face when fitted thereto, the first end portion providing an inner face which is substantially perpendicular to the axis of rotation of the roller assembly and spaced a distance from an outer edge of the outer face of the roller body, wherein a second roller assembly is receivable between respective inner faces of the side bodies.
24. 24. The grinding assembly according to claim 23 wherein the lateral face portion extending between the outer face and the bore of the roller body, or terminating adjacent thereto, substantially planar.
25. 25. The grinding assembly according to claim 23 or 24 wherein the side bodies comprise a second end portion which terminates at or adjacent a bore opening of the roller body;
26. 26. A roller assembly for the grinding of materials, the roller assembly having an outer face on a roller body, the outer face extending between two lateral faces, each lateral face being substantially planar, each junction of the respective lateral face with the outer face providing an edge portion, the roller assembly comprising:

    a plurality of side bodies adapted to be releasably secured to each lateral face of the roller whereby, when fitted, an inner surface of each side body abuts the lateral face, each side body comprises:

    a first end portion which terminates at a position above the roller's outer face when fitted thereto, the first end portion providing an inner face, the inner face being spaced outwardly relative to the inner surface of the side body, wherein a second roller assembly is receivable between the inner faces of the side bodies when the side bodies are secured to each lateral face of the roller body.
27. 27. The roller assembly according to claim 26 wherein the first end portion comprises a plurality of hard bodies to protect the first end portion from wear.
28. 28. A pressure roller assembly for use in the grinding of materials, the roller assembly having a cylindrical outer face defined between two lateral face portions, each lateral face portion being substantially planar, each lateral face portion co-operating with a plurality of replaceable side bodies secured thereto, each side body having at least a portion thereof in abutment with its respective lateral face portion, wherein one or more of the side plates has a first end portion which extends above the outer face of the roller body.
29. 29. A roller assembly for a pressure roller used in the grinding of materials, the roller having an outer face on a roller body, the outer face extending between two lateral face portions, each lateral face portion providing a substantially planar surface, the roller assembly comprising:

    a plurality of side bodies adapted to be releasably secured to the lateral face portions of the roller, whereby when fitted at least a portion of an inner surface of each side body abuts the lateral face portion, one or more or each of the side bodies comprises a first end portion which terminates at a position above the roller's outer face when fitted thereto, the first end portion presenting an inner face which is spaced outwardly relative to the lateral face portion, wherein a second roller assembly is receivable between the inner faces of each set of side bodies when they are secured to the respective lateral face portions of the roller body.
30. 30. The roller assembly according to claim 29 wherein each side body is secured to the lateral face by bolting the side body through the lateral face portion and into the roller body.
31. 31. The roller assembly according to claim 29 or 30 wherein one or more of the side bodies has an aperture therethrough in a region adjacent a second end portion of each side body.
32. 32. The roller assembly according to claim 31 wherein the aperture passes through the enlarged portion.
33. 33. The roller assembly according to claim 31 or 32 wherein the aperture is threaded and is adapted to receive a threaded fastener to assist with removing the side body from the roller.
34. 34. The roller assembly according to claim 31, 32 or 33 wherein the lateral face portion of the roller has a plurality of threaded holes extending into the roller, wherein the threaded holes align with the aperture of each side body when the side bodies are in position, such that when fitting a side body relative to the roller a fastener can placed through the aperture in the side body and into the roller to assist in securing the side body to the roller.
35. 35. The roller assembly according to claim 29 or 30 each side body has at least one protrusion extending therefrom, such that when the side body is secured to the lateral face of the roller the protrusion is received in a recess in the lateral face.
36. 36. The roller assembly according to any one of claims 29 to 35 wherein an outer face of the first end portion of the side bodies provides an extension to the outer surface of the roller.
37. 37. An ore grinding mill incorporating a pair of roller assemblies, wherein one of those roller assemblies is in accordance with any one claims 4 to 22, 26, 27, or 29 to 36, the rollers being supported in parallel spaced apart relationship and driven in contra-rotation so as in use to grind ore fed between the rollers.
38. 38. The ore grinding mill according to claim 37 wherein the position of the central axis of each roller assembly is fixed relative to each other.