AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION Innovation Patent Applicant: BRADKEN RESOURCES PTY LIMITED Invention Title: WEAR PLATE The following statement is a full description of this invention, including the best method for performing it known to us: -2 A WEAR PLATE Field of the Invention 5 The present invention relates to a wear plate for lining mineral processing and/or handling equipment in resource industries, including mineral processing and/or resource industries. 10 Background of the Invention In resource industries, it is often necessary to process and/or transport highly abrasive material. While it is possible to produce processing and transportation is structures/machinery with high structural strength, for example using suitable grades of steel, significant damage to the structures/machinery would still occur within a relatively short period of time. 20 With this problem in mind, it is known to provide processing and transportation structures/machinery with sacrificial wear plates which cover surfaces of the structures/machinery which come into contact with abrasive material during use. The wear plates are removable such 25 that after significant wearing of the wear plates, the wear plates may be replaced. However, existing wear plates tend to suffer from localised increased wearing, particularly next to join 30 lines between adjacent wear plates. Summary of the Invention In accordance with a first aspect of the present 35 invention, there is provided a wear plate for mineral handling equipment, the wear plate comprising: 23153731 (GHMatters) 21/06/10 - 3 a mounting device arranged to facilitate mounting of the wear plate to mineral handling equipment during use; and a surface plate disposed on a side of the wear plate 5 opposite to the mounting device, the surface plate being formed of wear resistant material; the shape of the wear plate being such that the surface plate tessellates with other similar wear plates; and io wherein the shape of the surface plate and the orientation of the surface plate relative to the mounting device are such that during use join lines defined between adjacently disposed surface plates are not substantially parallel to the intended direction of travel of material 15 across the surface plate. In one embodiment, the surface plate includes a recess which accommodates the mounting plate. 20 The configuration of the wear plate, including the shape, strength and abrasion resistance characteristics of the wear plate, may be selected according to the particular mineral handling equipment and particular mineral intended to be handled. 25 The shape of the wear plate may be a regular tessellating polygon or an irregular tessellating polygon. In one embodiment, the wear plate is substantially 30 hexagonal or diamond shaped, or any shape capable of tessellating with other similar such shapes and which is shaped such that, and is oriented relative to the mounting device such that, during use join lines defined between adjacently disposed surface plates are not substantially 35 parallel to the intended direction of travel of material. Similarly, any combination of shapes which together 23153731 (GHMatters) 21106/10 tessellate and are capable of being oriented such that during use join lines defined between adjacently disposed surface plates are not substantially parallel to the intended direction of travel of material is envisaged. 5 In one embodiment wherein the wear plate is generally hexagonal, the hexagon may have first and second opposed generally parallel sides which are relatively short and a plurality of angled sides which are relatively long. 10 Typically, embodiments of the invention use Ni-Hard material for the surface plate and especially type 4 Ni Hard is preferred as it has a martinistic white iron micro structure which is highly resistant to abrasion and also is provides resistance to impact forces. The mounting plate is typically formed of suitable steel material such as mild steel. 20 In accordance with a second aspect of the present invention, there is provided an item of material handling equipment comprising a plurality of wear plates as defined in the first aspect of the present invention, the plurality of wear plates being arranged in tessellating 25 arrangement relative to each other and being disposed such that during use join lines defined between adjacently disposed surface plates are not substantially parallel to the intended direction of travel of material across the surface plates. 30 Brief Description of the Drawings The present invention will now be described, by way of example only, with reference to the accompanying drawings, 35 in which: Figure 1 is a diagrammatic perspective view of an 23153731 (GHMatters) 21/06/10 embodiment of a wear plate in accordance with the present invention; Figure 2 is a diagrammatic plan view of the wear plate shown in Figure 1; 5 Figure 3 is a diagrammatic side view of the wear plate shown in Figure 1; Figure 4 is a diagrammatic rear view of the wear plate shown in Figure 1; Figure 5 is a diagrammatic sectional view taken along 10 the line A - A of Figure 4; Figure 6 is a diagrammatic plan view of an example first end plate for use with the wear plate shown in Figure 1; Figure 7 is a diagrammatic plan view of an example is second end plate for use with the wear plate shown in Figure 1; Figure 8 is a diagrammatic front view showing a typical layout of wear plates in accordance with Figures 1 to 7, with the wear plates shown in tessellating 20 arrangement during use; Figure 9 is a diagrammatic rear view of the wear plate layout shown in Figure 8; Figure 10 is a diagrammatic front view showing a typical layout of wear plates in accordance with an 25 alternative embodiment of the present invention; Figure 11 is a diagrammatic rear view of the wear plate layout shown in Figure 10; Figure 12 is a diagrammatic perspective view of a wear plate in accordance with a further alternative 30 embodiment of the present invention; Figure 13 is a diagrammatic side view of the wear plate shown in Figure 12; Figure 14 is a diagrammatic end view of the wear plate shown in Figure 12; 35 Figure 15 is a diagrammatic perspective view of an example first end plate for use with the wear plate shown in Figure 12; 23153731 (GHMatters) 21/06/10 -6 Figure 16 is a diagrammatic perspective view of a second end plate for use with the wear plate shown in Figure 12; Figure 17 is a diagrammatic plan view of a wear plate s in accordance with a further alternative embodiment of the present invention; Figure 18 is a diagrammatic plan view of an example first end plate for use with the wear plate shown in Figure 17; 10 Figure 19 is a diagrammatic plan view of an example second end plate for use with the wear plate shown in Figure 17; and Figure 20 is diagrammatic front view showing a typical layout of conventional wear plates shown in is tessellating arrangement during use. Description of an Embodiment of the Invention Referring to the drawings, in Figures 1 to 2 there is 20 shown a wear plate 10 having a wear resistant surface plate 12 and a mounting device 14 arranged to facilitate mounting of the wear plate 10 to an item of equipment such as mineral processing and/or handling equipment. 25 In this example, the mounting device 14 is fixed to the surface plate 12 by providing a recess in the surface plate 12 and fixing the mounting device 14 in the recess, for example using a suitable bonding agent. 30 However, it will be understood that other arrangements are possible. For example, the mounting device 14 may be integrally formed with the surface plate 12, or fixed to the surface plate 12 using other suitable fixing means, such as screws. 35 The surface plate 12 is formed of wear resistant material, for example of a type suitable for use in highly abrasive 23153731 (GHMatters) 21/06/10 -7 environments typically present in mineral processing and/or handling equipment in resource industries. In this example, the surface plate 12 is formed of Type 4 Ni-Hard material which has a martensitic white iron structure 5 which is highly resistant to abrasion. In the present embodiment, the mounting device 14 comprises a mounting plate 16 and several fixing projections 18. For example, four fixing projections 18 10 may be provided and each fixing projection 18 may comprise a threaded stud which screw threadably engages with a corresponding fixing nut in order to fix the wear plate 10 to an item of equipment during use. In this example, the mounting device 16 is formed of steel such as mild steel, 15 although it will be understood that any suitable material is envisaged. It will be understood that the configuration of the mounting device 14, in this example the configuration and 20 spacing of the studs 18, is selected based on the fixing arrangement present in an item of equipment with which the wear plate 10 is intended to be used. Accordingly, it will be understood that any suitable mounting device capable of achieving this purpose is envisaged. 25 Importantly, however, the wear plate 10 according to the present invention is not fixed to an item of equipment by providing apertures in the surface plate since such apertures can encourage a localised wearing effect to 30 occur adjacent the apertures. The shape of the surface plate 12 is selected such that the surface plate 12 is able to tesselate with other similar such surface plates, or to tessellate with other 35 shaped plates, and in this way a plurality of wear plates 12 are able to cover a desired area of an item of equipment by disposing the wear plates 10 in contiguous 23153731 (GHMatters) 21106/10 -8 relationship. In this example, the shape of the surface plate 12 is an irregular hexagon with two lines of symmetry. The hexagon includes two relatively short parallel sides 20 and four angled relatively long sides 5 22. In the present example, the size of each wear plates 10 in Figure 2 is approximately 450mm wide x 300mm high. 10 In order to enable complete coverage of an intended area of an item of equipment, supplementary wear plates of varying shapes may be provided, the particular shape of each supplementary wear plate being dependent on the shape required to cover edge portions of an intended coverage 15 area of an item of equipment. Example first and second supplementary wear plates 24, 26 are shown respectively in Figures 6 and 7. It has been discovered that if a tesselating arrangement 20 of wear plates is used in highly abrasive environments with join lines between adjacent wear plates which are generally parallel to the direction of travel of material during use, localised wearing tends to occur. A conventional arrangement of wear plates is shown in Figure 25 20 which illustrates a plurality of conventional square shaped wear plates 30 disposed in tesselating arrangement. Arrow A indicates the general direction of travel of material. As can be seen, join lines 32 between adjacent wear plates 30 generally align with the direction of 30 travel of material during use and this has a tendency to cause localised wearing at regions 34 where the end of a join line 32 meets an adjacent wear plate 30. The inventors of the present application have realised 35 that this localized wearing can be minimized by appropriately shaping the surface plates 12 and configuring the mounting device 14 so that during use when 23153731 (GHMatters) 21/06/10 -9 the wear plates 10 are fixed relative to an item of equipment, join lines between adjacent wear plates do not align with the general direction of travel of material. This is shown more clearly in Figures 8 and 9 which 5 respectively show front and rear views of a plurality of wear plates disposed in tesselating arrangement. The general direction of travel of material during use is indicated by Arrow B. As can be seen, join lines 36 between adjacently disposed wear plates 10 are not 10 generally parallel to the direction of travel B of material during use and as a consequence localised wearing of the type indicated by reference numeral 34 in Figure 20 is much less likely to occur. 15 With the above considerations as to minimisation of localised wearing of the type shown in Figure 20, it will be understood that any suitably shaped surface plate and any suitable associated fixing device is envisaged. For example, any suitable tesselating polygon in association 20 with a suitable mounting device arranged such that during use join lines between adjacent wear plates do not align with the general direction of movement of material during use are envisaged. 25 For example, as shown in Figures 10 and 11 a diamond shaped wear plate 40 is provided although other shapes are also possible. It will also be understood that surface plates formed of 30 materials other than Ni-Hard material may be used depending on the intended location and intended environment for the surface plates. For example, the surface plates may be formed of iron material, welded chromium carbide, tungsten carbide based materials, 35 polyurethanes, rubbers, quench and tempered steels, welded overlay materials, aluminium oxide ceramic cast in a polyurethane matrix, or any other suitable material. 23153731 (GHMatters) 21/06i10 - 10 It will be appreciated that the particular wear plates used in relation to an item of equipment is dependent on the abrasiveness of the material with which the equipment 5 is intended to be used. In addition, as shown in Figures 12 to 16, the surface plates may be configured so as to include a plurality of channels which define a series of bars. Figure 12 shows a io wear plate 50 of white iron material formed in this way, and Figures 13 and 14 respectively show side and end views of the wear plate 50. Figures 15 and 16 show by example first and second supplementary wear plates 52, 54 which may be used to enable complete coverage of an intended 15 area of an item of equipment. A further wear plate 60 formed of ceramic material is shown in Figure 17. Associated first and second supplementary wear plates 62, 64 which may be used to 20 enable complete coverage of an intended area of an item of equipment are respectively shown in Figures 18 and 19. It will be appreciated that the wear plates according to the present invention may be used in any suitable 2S equipment that is intended to handle abrasive material. For example, the present wear plates may be used for lining chutes and mineral processing and/or handling equipment in resource industries. 30 Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention. 23153731 (GHMatters) 21/06/10