Technical Field

[0001] A wear element, a composite wear surface liner for a crusher or a chute, a method and system for casting a wear surface liner for a crusher or a chute are disclosed, and a retainer for use therewith.

Background

[0002] Crushers are used in the mining and construction industries for reducing large rocks into smaller rocks, gravel, or grit. Crushers typically hold rock material between two parallel or tangent solid metal surfaces and apply force to bring the surfaces together to fracture or deform the rock material. Crushers take various forms including jaw crushers, gyratory crushers, cone crushers, horizontal shaft impactors and vertical shaft impactors.

[0003] The crushing surfaces are subject to rapid wear because of the inherent abrasive action of the rock material. Consequently, the crushing surfaces are generally lined with a wear surface liner formed from a hardened wear resistant material.

Necessarily, the wear surface liner is also subject to wear and must be replaced on a regular basis, leading to process downtime while the crusher undergoes maintenance and reduced productivity.

[0004] It is known to enhance the wear life of a wear surface liner by providing the wear surface liner with hardened inserts in the crushing surface of the wear surface liner, thereby providing a composite wear surface liner. The composite wear surface liner may be fabricated by pre-casting the wear surface liner with a plurality of recesses or cavities in the crushing surface and then inserting or press-fitting the hardened inserts into the plurality of recesses or cavities. However, the fabrication of the composite wear surface liner in this manner is time-consuming and, further, the hardened inserts have a tendency to be dislodged from their respective recesses or cavities during the crushing operation, thereby entering the downstream processing stream, detracting from the wear life of the composite wear surface liner and potentially damaging downstream machinery.

[0005] The above references to background art do not constitute an admission that the art forms a part of the common general knowledge of a person of ordinary skill in the art. The above references are also not intended to limit the application of the wear element, a composite wear surface liner for a crusher or a chute, a method and system for casting a wear surface for a crusher or a chute as disclosed herein, and a retainer for use therewith.

Summary

[0006] Generally, a wear element, a composite wear surface liner for a crusher or a chute, a method and system for casting a wear surface liner for a crusher or a chute, and a retainer for use therewith are disclosed.

[0007] The present disclosure describes a wear element for a composite wear surface liner comprising a wear element body and an extension associated with an end of the wear element body. In use, the extension is configured to be received in a retainer disposed in a mould for a composite wear surface liner, the wear element associated with the extension being retained in a corresponding mould cavity of the mould and thereby embedded in the composite wear surface liner when molten castable material is poured into the mould cavity.

[0008] In one embodiment, the extension comprises a stem extending from an end face of the wear element body.

[0009] In another embodiment, the extension comprises a plurality of prongs extending from a peripheral surface of the end of the wear element body. [0010] In another embodiment, the extension comprises a hollow pipe configured to engage a peripheral outer surface of the end of the wear element body. The hollow pipe may be provided with apertures therein to allow the passage of molten castable material therethrough.

[0011] In another embodiment, the extension comprises a clamp configured to engage the end of the wear element body. In one form the clamp may be a two-piece hollow pipe configured to engage a peripheral outer surface of the end of the wear element body.

[0012] In some embodiments, a pair of stems may extend from the end face of the wear element body.

[0013] In one form, the stem may be fixed to the end face of the wear element body. Alternatively, the stem may protrude from the end face of the wear element body, wherein a portion of the stem is embedded in the wear element body. In this alternative form, the wear element body may be cast or formed with the portion of the stem embedded in the wear element body. Alternatively, the wear element body may be provided with a recess configured to receive the stem. In another form, the stem may be integral with the wear element body and formed from the same material.

[0014] The wear element body may comprise a material having a typical overall hardness of 500-700 Brinell hardness. The term Overall hardness' as used herein refers to the hardness of the end face of the wear element body rather than to the hardness of any discrete elements comprised in the wear element body . In some embodiments the material of the wear element body may be a composite material comprising carbides or other materials having a hardness greater than 700 Brinell hardness embedded or dispersed in a matrix material.

[0015] In some embodiments the stem may comprise a different material from the wear element body. In particular, the stem may comprise a material having a higher melting point than a castable base material from which a wear liner body is cast. In some forms, wherein the wear element body may be cast or formed with the portion of the stem embedded in the wear element body, the stem may comprise a material having a higher melting point than the wear element body.

[0016] In one embodiment the wear element body is configured to be capable of fragmenting into smaller sized portions. The smaller sized portions may have a predetermined size. In one form, a cross-sectional area of the wear element body varies along a longitudinal axis thereof in a manner to define the smaller sized portions having predetermined size. For example, at one or more regions along the longitudinal axis of the wear element body, the cross-sectional area of the wear element body may be sufficiently small relative to the cross-sectional area of the wear element body than other than at the one or more regions to define one or more fracture points substantially perpendicular to the longitudinal axis of the wear element body.

[0017] The cross-sectional area of the wear element body may increase or decrease along the longitudinal axis of the wear element body. In use, a dimension of an exposed face of the wear element body may be used to indicate a predetermined measure of wear in a wear surface. For example, a diameter or surface area of the exposed face may be used to indicate the predetermined measure of wear in the wear surface, in particular a depth of wear in the wear surface of a composite wear surface liner for a crusher or a chute.

[0018] In another embodiment, a cross-sectional area of the wear element body may be circular, oval, diamond-shaped, elongated, triangular, quadrangular, parallelogram, polygon or irregularly- shaped. In one preferred form, the cross-sectional area of the wear element body may be shaped to allow a plurality of the wear elements to be arranged in an array whereby adjacent rows and columns of the wear elements may be nested within one another.

[0019] In use, a plurality of the wear elements are embedded into a wear surface liner body to provide a composite wear surface liner for a crusher or a chute, thereby enhancing the abrasive capacity of said liner and extending its wear life relative to conventional liners.

[0020] Accordingly, in a second aspect of the disclosure, there is provided a composite wear surface liner for a crusher or a chute comprising a wear surface liner body having a wear surface and a plurality of wear elements embedded in the wear surface liner body, wherein the wear element comprises a wear element body and an extension associated with an end of the wear element body, whereby the end of the wear element is disposed at or below the wear surface of the wear surface liner body.

[0021] In use, any portion of an extension extending beyond the wear surface of the wear surface liner body may be removed prior to use of the composite wear surface liner in the crusher or the chute.

[0022] In an alternative aspect of the disclosure, there is provided a composite wear surface liner for a crusher or a chute comprising a wear surface liner body having a wear surface and a plurality of wear elements embedded in the wear surface liner body in an arrangement whereby an end face of the wear element is disposed at the wear surface of the wear surface liner body, wherein respective end faces of adjacent wear elements are shaped and/or arranged with respect to one another to disrupt a wear path in one or more directions of wear on a wear surface of the composite wear surface liner.

[0023] In one particular embodiment, the plurality of wear elements are shaped and arranged in an array whereby adjacent rows and columns of the end faces of the plurality of wear elements in the array can be nested in one another.

[0024] In another particular embodiment, a plurality of first wear elements may be arranged in an array and a plurality of second wear elements may be disposed in a plurality of interstitial spaces between adjacent first wear elements in the array. The second wear elements may have smaller end faces than the end faces of the first wear elements. Additionally or alternatively, the second wear elements may have different shaped end faces than the end faces of the first wear elements. [0025] In one embodiment, an opposing end face of the wear element body may be disposed at a predetermined depth in the wear surface liner body substantially coinciding with a minimum liner thickness, thereby indicating degree of wear of the liner.

[0026] The wear surface liner body comprises a castable material having a lower Brinell hardness than the wear element body.

[0027] In one embodiment the plurality of wear elements disposed at or below the wear surface of the wear surface liner body may occupy from 10 to 70%, preferably from 17% to 67% of the area of the wear surface. In one form, the plurality of wear elements are regularly spaced apart from adjacent wear elements. The wear elements may be spaced apart from adjacent wear elements more closely in portion(s) of the wear surface of the composite wear surface liner which is/are subject to high wear than other portion(s) of the wear surface which is/are subject to low wear.

[0028] The plurality of wear elements as described above may be embedded in the wear surface liner body by retaining the plurality of wear elements in a mould cavity defined by a mould for the composite wear surface liner and casting a castable material into the mould cavity. The plurality of wear elements may be retained in the mould cavity by one or more retainers which may be adapted to receive the extensions associated with the wear element bodies. The retainer may be adapted to retain the one or more wear elements in a desired position in the mould cavity while molten castable material is poured into the mould cavity, thereby embedding the plurality of wear elements into the castable material to form the composite wear surface liner.

[0029] Accordingly, in a third aspect of the disclosure, there is provided a retainer for retaining one or more wear elements in a mould cavity defined by a mould for forming a composite wear surface liner, wherein the wear element comprises a wear element body and an extension associated with an end of the wear element body.. [0030] In one embodiment the retainer may comprise a body adapted to be received in the mould for forming a composite wear surface liner, the retainer body having opposing faces, a first opposing face being arranged in use to abut a recessed surface in the mould and a second opposing face being arranged in use to be aligned with a mould cavity surface, wherein the second opposing face is provided with one or more recesses adapted to receive respective extensions associated with the one or more wear element bodies. The extension associated with the wear element body may be received in the recess of the retainer in a friction fit.

[0031] In one embodiment a plurality of recesses in the second opposing face of the retainer may be regularly spaced apart so that the extensions and the wear element bodies associated therewith of adjacent wear elements are regularly spaced apart from one another.

[0032] The retainer body may be configured to facilitate a regular arrangement with adjacent retainer bodies received in the mould. In particular, the adjacent retainer bodies may be configured to mutually co-locate with respect to each other to provide regular spacing between the wear elements received therein, thereby providing a retainer assembly. In one embodiment, the retainer body may be L- shaped or V- shaped. In this particular embodiment a plurality of V-shaped retainer bodies may be alternately disposed adjacent to a plurality of inverted V-shaped retainer bodies.

[0033] The retainer may be fabricated from the same or similar material to the mould. Alternatively, the retainer may be fabricated from material having the same or similar thermal properties to the mould. Alternatively, the retainer may be fabricated from the same or similar material to one or more cores used in a moulding or casting process.

[0034] Alternatively, the retainer as described above may be integrally formed with the mould. In this respect, there is provided a mould for forming a composite wear surface liner comprising a retainer portion disposed therein, the retainer portion having a face aligned with a mould cavity surface, wherein the face of the retainer portion is provided with a plurality of recesses adapted to receive respective stems of a plurality of wear element bodies, preferably in a friction fit. The recesses in the face of the retainer portion may be regularly spaced so that the stems and the wear element bodies extending therefrom of adjacent wear elements are regularly spaced apart from one another.

[0035] In another aspect of the disclosure, there is provided a core box for use with a mould for forming a composite wear surface liner, the core box being adapted to retain a retainer or a retainer assembly as described above. In one embodiment, the core box may be adapted to pre-heat the retainer or retainer assembly and/or the plurality of wear elements retained therein prior to pouring molten castable material into the mould. In one form, the core box may be adapted to pre-heat the retainer or retainer assembly and/or the plurality of wear elements by conduction, convection and/or radiant heating.

[0036] Alternatively, the mould for forming a composite wear surface liner may be adapted to pre-heat the mould cavity and/or the plurality of wear elements retained in the retainer or retainer assembly. In one embodiment, the mould may be configured to be provided with a small reservoir for receiving molten castable material, wherein heat generated from the molten castable material in the small reservoir may be used to preheat the plurality of wear elements retained in the retainer or retainer assembly.

[0037] In another aspect of the disclosure, there is provided a system for forming a composite wear surface liner, said system comprising a plurality of wear elements; a mould defining a mould cavity configured to form a composite wear surface liner body from a castable material; a plurality of retainers or a retainer assembly disposed in the mould for retaining the plurality of wear elements in the mould cavity; and a gating system for receiving and distributing molten castable material into the mould cavity of the mould.

[0038] In one embodiment, the retainer may be integrally formed with the gating system. [0039] In another aspect of the disclosure, there is provided a method of forming a composite wear surface liner, said method comprising the steps of:

a) providing a plurality of wear elements, wherein each wear element comprises a wear element body and an extension associated with an end of the wear element body;

b) providing a mould defining a mould cavity configured to form a composite wear surface liner body from a castable material, wherein the mould is provided with a plurality of retainers or a retainer assembly disposed therein, the plurality of retainers or retainer assembly being adapted to retain a plurality of wear elements in the mould cavity;

c) engaging the extensions associated with the plurality of wear elements with the plurality of retainers or retainer assembly or the mould whereby the wear element bodies of the plurality of wear elements are disposed in the mould cavity;

d) pouring molten castable material into the mould cavity to form the wear surface liner body, thereby embedding the wear element bodies of the wear elements in the wear surface liner body and forming the composite wear surface liner;

e) allowing the molten castable material in the mould cavity to cool and harden; and,

f) separating the composite wear surface liner from the mould.

[0040] After separating the composite wear surface liner from the mould, the stems which protrude from a wear surface of the composite wear surface liner may be removed by machining or other suitable techniques.

Brief Description of Drawings

[0041] Notwithstanding any other forms which may fall within the scope of the wear element, a composite wear surface for a crusher or a chute, and a method and system for casting a wear surface for a crusher or a chute as set forth in the Summary, specific embodiments will now be described, by way of example only, with reference to the accompanying drawings in which: [0042] Figure 1 is a schematic representation of one embodiment of a wear element in accordance with the disclosure;

[0043] Figure 2 is a schematic representation of an alternative embodiment of a wear element in accordance with the disclosure;

[0044] Figure 3 is a schematic representation of another embodiment of a wear element in accordance with the disclosure;

[0045] Figure 4 is a schematic representation of yet another embodiment of a wear element in accordance with the disclosure;

[0046] Figure 5 is a schematic representation of one embodiment of a composite wear surface liner, in the form of a mantle for a cone crusher, in accordance with the disclosure, prior to removal of the stems protruding from a wear surface of the composite wear surface liner;

[0047] Figure 6 is a schematic representation of the composite wear surface liner shown in Figure 5 after machining a wear surface of the composite wear surface liner;

[0048] Figure 7 is a schematic representation of the composite wear surface liner shown in Figure 6 which has been subject to a period of wear;

[0049] Figures 8a and 8b are schematic representations of different views of one embodiment of a retainer in accordance with the disclosure, wherein a plurality of wear elements as shown in Figure 3 are retained in the retainer;

[0050] Figure 9 is a schematic representation of one embodiment of a part section of a mould for a composite wear surface liner, in the form of a mantle for a cone crusher, wherein the mould is adapted to receive a plurality of retainers as shown in Figures 8a and 8b; [0051] Figure 10 is a schematic representation of one embodiment of the part section of the mould shown in Figure 9 having a plurality of retainers assembled into the mould;

[0052] Figures 1 la, 1 lb and 1 lc are respective plan view and cross-sectional representations along section A-A and section B-B of one embodiment of a system for forming a composite wear surface liner, in the form of a mantle for a cone crusher, in accordance with the disclosure;

[0053] Figure 12 is a schematic representation of one embodiment of a composite wear surface liner, in the form of a mantle for a cone crusher, in accordance with the disclosure after it has been removed from the mould with a gating system still in place;

[0054] Figures 13a- 13j are a series of schematic representations depicting various retainers and a plurality of wear elements arranged in varying arrays in the retainers; and,

[0055] Figures 14a- 14d are a series of schematic representations depicting one embodiment of a secondary mould for use with the mould for the composite wear surface liner and the retainers as disclosed herein.

Description of Embodiments

[0056] Embodiments of a wear element, a composite wear surface liner for a crusher or a chute, a method and system for casting a wear surface liner for a crusher or a chute are disclosed, and a retainer for use therewith will now be described by way of example only.

[0057] Referring to the figures there is shown several embodiments of a wear element 10 for use in a composite wear surface liner 100 for a crusher or a chute. The composite wear surface liner 100 includes a plurality of wear elements 10 embedded in a wear surface liner body 110. It will be appreciated that the wear surface liner body 110 of the composite wear surface liner 100 may be configured to be mounted on a wear surface of any suitable crusher. For example, the crusher may be a jaw crusher, gyratory crusher, cone crusher, horizontal shaft impactor or a vertical shaft impactor. Alternatively, the wear surface liner body 110 may be configured to be mounted on a wear surface of any suitable chute for conveying hard, abrasive materials.

[0058] The wear surface liner body 110 may be formed from a castable material having a hardness of about 200 Brinell hardness. Examples of suitable castable materials include, but are not limited to, steel; manganese steel with hardness 200-250 Brinell hardness as-cast and up to 550-600 Brinell hardness when work hardened; chromium molybdenum and nickel chrome molybdenum steel alloys having a hardness of 250-550 Brinell hardness; white iron with harness up to 700 Brinell hardness; or high chrome content steel allows with hardness up to 700 Brinell hardness. Generally, the wear surface liner body 110 is formed by pouring molten castable material into a mould cavity 202 of a mould 200 for forming the wear surface liner body 110.

[0059] The wear element 10 includes a wear element body 12 having a front end face 14a and a rear end face 14b and a stem 16 extending from the front end face 14a.

Generally, the stem 16 extends in co-axial alignment with the wear element body 12. In some embodiments, as shown in Figures 2 to 4, the wear element 10 may include a pair of stems 16 extending from the front end face 14a.

[0060] A free end 18 of the stem(s) 16 may be provided with a foot 18a.

Alternatively, free ends 18 of the pair of stems 16 may curve away from one another as shown in Figures 2 and 4.

[0061] In use, a plurality of the wear elements 10 are embedded into the wear surface liner body 110 to provide a composite wear surface liner 100 for a crusher or a chute, thereby enhancing the abrasive capacity of said liner 100 and extending its wear life relative to conventional liners. The wear elements 10 may be embedded in the wear surface liner body 110 so that the front end face 14a may be disposed at or marginally below (e.g. 5-10 mm) a wear surface 102 of the composite wear surface liner 100. [0062] The wear elements 10 may be embedded in the wear surface liner body 110 in a manner whereby the respective end faces 14a of adjacent wear elements are shaped and/or arranged with respect to one another to disrupt a wear path in one or more directions of wear on a wear surface 102 of the composite wear surface liner 100. For example, the plurality of wear elements 10 may be shaped and/or arranged in an array whereby adjacent rows and columns of the wear elements 10 in the array can be nested in one another, as shown in Figures 13a- 13c. In particular for wear elements 10 having a diamond- shaped end face 14a, in effect, the end faces 14a in adjacent rows and columns of the array Overlap' one another, thereby disrupting a wear path in a horizontal and a vertical direction of wear. Alternatively, as shown in Figures 13e-13h the plurality of wear elements 10 may be arranged in the array and smaller diameter wear elements 10' can be disposed in a plurality of interstitial spaces between adjacent wear elements 10 in the array. The smaller diameter wear elements 10' may have different shaped end faces 14a' than respective end faces 14a of the wear elements 10 in the array, as shown in Figure 13j.

[0063] The wear elements 10 may occupy from 10 to 70%, preferably from 17% to 67% of the area of the wear surface 102. In certain areas where the wear surface 102 is subject to high wear, the wear elements 10 may be more closely spaced from adjacent wear elements 10 than areas of the wear surface 102 less subject to wear.

[0064] The wear element body 12 may comprise a material having a overall hardness of 500-600 Brinell hardness. Illustrative examples of suitable materials include, but are not limited to, ceramic materials such as aluminium oxide, partly stabilised zirconium oxide, silicon oxide, a metal nitride or a metal boride; hard metals such as tungsten carbide-cobalt (WC-Co), titanium carbine-iron (TiC-Fe), titanium carbide -nickel- molybdenum (TiC-Ni-Mb); or composite materials of metal and ceramic, so-called Cermet, where the metal functions as a binder for ceramic particles. Typical binders may be, for example, cobalt, and the binder content may be 10-70 wt%. Other metals that may be used as binder are cobalt based alloys, nickel or nickel based alloys, titanium or titanium based alloys, iron or iron based alloys, molybdenum or molybdenum based alloys, silicon or boron. In particular, the binder may be an iron- manganese alloy that is similar to, and compatible with, the castable material of the wear surface liner body 110. The ceramic may be any suitable boride, oxide or carbide material, including but not limited to, tungsten carbide (WC), fused tungsten carbide, titanium carbide (TiC), vanadium carbide (VC), chromium carbide (G-3C2), niobium carbide (NbC), molybdenum carbide (MoC), aluminium oxide, or mixture of several carbides.

[0065] Typically, the wear element body 12 may be cylindrical in shape or take the form of a rectangular prism having dimensions of about 20 mm x 50 mm. It will be appreciated, however, that the wear element body 12 may take any suitable shape and a cross-section of the wear element body 12 may be circular, oval, diamond-shaped, elongated, triangular, quadrangular, parallelogram, polygon or irregularly-shaped.

[0066] In one embodiment, as shown in Figure 2, the wear element body 12 is configured to be capable of fragmenting into smaller sized portions 12a, 12b, 12c. If the wear element 10 should become dislodged from the composite wear surface liner 100, the wear element body 12 is advantageously able to fragment into smaller pieces, thereby protecting the crusher or chute and its downstream components from damage from what would have been a larger sized wear element body 12.

[0067] The smaller sized portions 12a, 12b, 12c may have a predetermined size. In one form, a cross-sectional area of the wear element body 12 varies along a

longitudinal axis thereof in a manner to define the smaller sized portions 12a, 12b, 12c having predetermined size. For example, at one or more regions 12d along the longitudinal axis of the wear element body 12, the cross-sectional area of the wear element body 12 may be sufficiently small relative to the cross-sectional area of the wear element body other than at the one or more regions 12d to define one or more fracture points 12e substantially perpendicular to the longitudinal axis of the wear element body 12.

[0068] In another embodiment, as shown in Figure 3, a cross-sectional area of the wear element body 12 may increase or decrease along the longitudinal axis of the wear element body from front end face 14a to rear end face 14b. In other words, the wear element body 12 may be tapered from front end face 14a to rear end face 14b. In some embodiments, the rear end face 14b may be bevelled or rounded on its respective edges to minimise stress concentrations. The rear end face 14b may have a larger cross- sectional area than the front end face 14a of the wear element body 12 to make it more difficult for the wear element body 12 to be dislodged from the wear surface liner body 110.

[0069] As shown in Figures 1 to 4, the stem 16 may be fixed to the front end face 14a of the wear element body 12 or the stem 16 may protrude from the front end face 14a of the wear element body 12, wherein a portion 20 of the stem 16 is embedded in the wear element body 12.

[0070] The portion 20 of the stem 16 may be embedded in the wear element body by casting the wear element body 12 around the portion 20 of the stem 16. Alternatively, the wear element body 12 may be provided with a recess (not shown) configured to receive the stem 16 in a friction fit.

[0071] In an alternative embodiment (not shown), the stem 16 may be integral with the wear element body 12 and formed from the same material.

[0072] The stem 16 may be a different material from the wear element body 12. For example, the stem 16 may be a brittle material which can be readily removed from a wear surface 102 of the composite wear surface liner 100. In particular, the stem 16 may be a material having a higher melting point than a castable material from which the composite wear liner body 110 is cast. In some forms, wherein the wear element body 12 may be cast or formed with the portion of the stem 16 embedded in the wear element body 12, the stem 16 may comprise a material having a higher melting point than the wear element body 12.

[0073] The stem(s) 16 may be fabricated from any suitable material including, but not limited to, stainless steel or other iron-based alloys containing high levels of chrome; refractory metals such as niobium, titanium and molybdenum. Alternatively, the stem(s) 16 may be fabricated from low grade steel or iron coated with a suitable ceramic or sand casting material to insulate the metal from ambient casting

temperatures.

[0074] In use, the wear elements 10 are embedded into the composite wear liner body 110 by positioning and retaining a plurality of the wear elements 10 in the mould cavity 202 by means of their respective stems 16 in a plurality of retainers 20. The retainers 20 may be configured in a retainer assembly 22 in the mould 200 for the composite wear liner body 110, thereby retaining the plurality of wear elements 100 in a desired location in the mould cavity 202 while molten castable material is poured into the mould cavity 202.

[0075] After removal of the composite wear liner 100 from the mould 200, the free ends 18 of the stems 16 protrude from the wear surface 102 of the composite wear liner 100, as shown in Figure 5. The free ends 18 and the protruding stems 16 may be removed by machining or other suitable removal processes to provide the composite wear liner 100 as shown in Figure 6. Depending on the location of the front face 14a of the wear element body 12 with respect to the wear surface 102 of the composite wear surface liner 100, the front face 14a may be exposed or lie marginally below (e.g. 5-10 mm) the wear surface 102.

[0076] A dimension of an exposed face of the wear element body 12 may be used to indicate a predetermined measure of wear of the wear surface 102 of the composite wear surface liner 100 in which the wear element body 12 is embedded, as shown in Figure 7. Typically, the exposed face of the wear element body 12 will be the front end face 14a. For example, a diameter or surface area of the exposed face may be used to indicate the predetermined measure of wear in the wear surface 102 , in particular a depth of wear in the wear surface 102 of a composite wear surface liner 100 for a crusher or a chute as described herein. [0077] Referring to Figures 8 to 10, there is shown a retainer 20 and a retainer assembly 22 for retaining three wear elements 10 in the mould cavity 202 of the mould 200.

[0078] The retainer 20 comprises a body 24 adapted to be received in the mould 200 for forming the composite wear surface liner 100 and one or more recesses 26 therein for receiving and retaining the stem(s) 16 of the wear element 10. The stem(s) 16 of the wear elements 10 may be received in respective recesses 26 of the retainer 20 in a friction fit.

[0079] The retainer body 24 has a pair of opposing faces 28a, 28b. A first opposing face 28a is arranged, in use, to abut a recessed surface 202 in the mould 200 as shown in Figure 6. A second opposing face 28b is arranged, in use, to be aligned with a mould cavity surface 204 as shown in Figure 6.

[0080] Alternatively, with reference to Figures 14a to 14d, the mould 200 may be provided with a secondary mould 210 having a pair of mating portions 210a, 210b, wherein the secondary mould 210 is received in the mould 200. The mating portions 210a, 210b of the secondary mould 210 may be configured to engage one or more wear elements 10, as shown in Figure 14a, or one or more retainer bodies 24 and respective wear elements 10 therebetween, as shown in Figure 14d. In embodiments where a gap 212 is defined between the mating portions 210a, 210b, the gap 212 may then be filled with moulding material 214, such as chromite sand, as shown in Figures 14c and 14d. The moulding material is compacted around the stems 16 of the wear elements 10, thereby retaining the wear element bodies 12 in the mould cavity 202.

[0081] As shown in Figures 8a and 8b, the recesses 26 in the second opposing face 28b of the retainer 20 are regularly spaced apart so that the stems 16 and the wear element bodies 12 extending therefrom are regularly spaced apart from one another.

[0082] The retainer body 24 may be configured to facilitate a regular arrangement with adjacent retainer bodies 24 received in the mould 200. In particular, the adjacent retainer bodies 24 may be configured to mutually co-locate with respect to each other to provide regular spacing between the wear elements 10 received therein. A plurality of co-located adjacent retainer bodies 24 comprise the retainer assembly 22. In one embodiment, the retainer body 24 may be L-shaped. In this particular embodiment a plurality of L-shaped retainer bodies 24 may be alternately disposed adjacent to a plurality of inverted L-shaped retainer bodies 24. Alternatively, the retainer bodies 24 may be V-shaped.

[0083] The retainer 20 may be fabricated from the same or similar material to the mould 200. Alternatively, the retainer 20 may be fabricated from material having the same or similar thermal properties to the mould 200.

[0084] Alternatively, the retainer assembly 22 may be integrally formed with the mould 200 (not shown). In this particular embodiment, the mould 200 may include a retainer portion which defines a plurality of recesses in the mould cavity surface 202, wherein the recesses are adapted for receiving and retaining the stem(s) 16 of the wear elements 10, preferably in a friction fit. The recesses in the retainer portion may be regularly spaced so that the stems 16 and the wear element bodies 12 extending therefrom of adjacent wear elements 10 are regularly spaced apart from one another.

[0085] The mould 200 comprises a core box. The core box may be adapted to retain a retainer 20 or a retainer assembly 22 as described above. The core box may also be adapted to pre-heat the retainer 20 or retainer assembly 22 and/or the plurality of wear elements 10 retained therein prior to pouring molten castable material into the mould 200.

[0086] Pre-heating of the retainers 20 and/or wear elements 10 may be achieved by conduction, convection and/or radiant heating. For example, an electric heating coil may be associated with one or more of the retainers 20, in particular when the retainers 20 are formed from a heat conducting material. In another form, a magnetic induction coil may be utilised to heat the retainers 20 and the wear elements 10 from within the mould 200. In another form, a hot gas may be forced into the mould cavity or into a secondary cavity in heat exchange relation with the wear elements 10 or the retainers 20. Alternatively, the air inside the mould cavity may be heated by pouring a small amount of molten metal into the mould cavity or the secondary cavity in heat exchange relation with the wear elements 10 or the retainers 20.

[0087] Alternatively, the mould 200 for forming the composite wear surface liner 100 may be adapted to pre-heat the mould cavity and/or the plurality of wear elements 10 retained in the retainer 20 or retainer assembly 22. In one embodiment, the mould 200 may be configured to be provided with a small reservoir for receiving molten castable material, wherein heat generated from the molten castable material in the small reservoir may be used to pre-heat the plurality of wear elements retained in the retainer 20 or retainer assembly 22.

[0088] Referring to Figures 1 la-1 lc there is shown a system 300 for fabricating a composite wear surface liner 100. The system 100 includes a plurality of wear elements 10 as described previously, a mould 200 defining a mould cavity 202 configured to form a composite wear surface liner body 110 from a castable material, a plurality of retainers 20 or a retainer assembly 22 disposed in the mould 200 for retaining the plurality of wear elements 10 in the mould cavity 202, and a gating system 302 for receiving and distributing molten castable material into the mould cavity 202 of the mould 200.

[0089] The gating system 302 includes a sprue 304 for receiving the molten castable material into the gating system 302 and a gating 306 configured to allow molten castable material to flow therethrough and into the mould cavity. The gating system 302 may further comprise one or more risers 308 for receiving additional molten castable material into the gating system 302 and thence the mould cavity 202 to compensate for shrinkage of the molten castable material as it cools and solidifies into the composite wear surface liner body 102.

[0090] In use, the composite wear surface liner 100 may be formed by disposing a plurality of retainers 20 in corresponding recesses in the mould 200. The plurality of retainers 20 ensure that the wear elements 10 are regularly spaced apart from one another. In one embodiment, the retainers 20 may be mutually co-located with respect to one another, to ensure regular spacing between the wear elements 10.

[0091] The stems 16 of a plurality of wear elements 10 may be inserted in respective recesses 26 of the retainer bodies 24 so that the wear element bodies 12 extend into the mould cavity 202 in a desired position. For example, the length of the stems 16 and/or the depth of the recesses 26 in the retainer bodies 24 may be selected so that the wear element bodies 12 would be disposed at or marginally below the wear surface 102 of the wear surface liner body 110.

[0092] Molten castable material is then poured into the sprue 304 of the gating system 302 and flows through the gating 306 into the mould cavity 202, thereby embedding the wear element bodies 12 into the wear surface liner body 110. Additionally, molten castable material may be poured into the mould cavity 202.

[0093] The molten castable material is then allowed to cool and harden before separating the composite wear surface liner 100 from the mould 200. The composite wear surface liner 100 may be removed from the mould 200 or the mould 200 may be removed from the composite wear surface liner 100.

[0094] After separation of the composite wear liner 100 and the mould 200, the free ends 18 of the stems 16 protrude from the wear surface 102 of the composite wear liner 100, as shown in Figure 5. The protruding stems 16 may be removed by machining or other suitable techniques.

[0095] It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the above-described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. [0096] For example, the wear element 10 may include a wear element body 12 and an extension associated with the wear element body, in which the extension may take one of several alternative forms. The extension may comprise a plurality of prongs extending from a peripheral surface of the end of the wear element body 12.

Alternatively, the extension may comprise a hollow pipe configured to engage a peripheral outer surface of the end of the wear element body 12. The hollow pipe may be provided with apertures therein to allow the passage of molten castable material therethrough. In another embodiment, the extension may be a clamp configured to engage the end of the wear element body. In one form the clamp may be a two-piece hollow pipe configured to engage a peripheral outer surface of the end of the wear element body.

[0097] In the claims which follow, and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word "comprise" and variations such as "comprises" or "comprising" are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments as disclosed herein.