AU2012238221B2 - A Liner Assembly for Indicating Wear in a Crusher - Google Patents

Abstract

A liner assembly for indicating wear of a liner to protect an underlying surface is provided. The liner assembly includes a liner for protecting the underlying surface from 5 wear and one or more indicators arranged to be disposed on a side of the liner. The one or more indicators are spaced from the front face by a distance corresponding, respectively, to a predetermined degree of wear from the front face of the liner in an arrangement whereby, in use, exposure of one of the one or more indicators indicates the degree of wear from the front face of the liner. One or more markings may be disposed on the side of said liner and spaced from the front face by a distance corresponding, respectively to the predetermined degree of wear from the front face of the liner. The one or more indicators may be positioned, respectively, adjacent to the one or more markings. The one or more markings can is comprise grooves extending into the liner. In this arrangement, the one or more indicators can be arranged to be received, respectively, in the one or more grooves. 374480 1 (GHMatters) PB8123.AU.2 Cl C4

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION Standard Patent Applicant(s): CRUSHING & MINING EQUIPMENT PTY LTD Invention Title: A Liner Assembly for Indicating Wear in a Crusher The following statement is a full description of this invention, including the best method for performing it known to me/us: 2 A LINER ASSEMBLY FOR INDICATING WEAR IN A CRUSHER Technical Field s A liner for protecting an underlying surface from wear, a liner assembly for indicating wear of the surface, and a method and system for determining the degree of wear of the surface, are disclosed. Background Art 10 A gyratory crusher is one of the main types of primary crushers used in mines, quarries, or ore processing plants. The gyratory crusher includes a fixed outer shell assembly having a concave surface and an inner conical head which gyrates about a vertical spindle. The crushing action is caused by the closing of the gap between the 15 moving inner conical head and a plurality of fixed concave liners which are mounted to the outer shell. The concave liners are mounted to the outer shell in tiered rows. A bottom row of concave liners is first constructed by arranging a plurality of concave liners in a row 20 with regular spacing between adjacent concave liners. Spacers, such as wooden strips, may be placed in each joint to ensure regular spacing between adjacent concave liners. The joints between the concave liners and below the concave liners may be sealed with a suitable sealant, such as silicone or an oil-based putty. The back surface of the concave liner is adhered to a surface of the outer shell with a suitable 25 backing material, such as hot zinc or an epoxy-based adhesive. Typically, the backing material is poured into a gap between the back surface of the concave liner and the outer shell. A further row of concave liners is then arranged above the bottom row in a similar fashion, and so on until the outer shell surface is covered. 30 During the operational life of the gyratory crusher, the fixed concave liners and mantle liner become worn and need to be replaced. Most sites will only have a single gyratory crusher, and the gyratory crusher acts as a transfer point between the mine and the rest of the processing plant. As such, it is generally necessary to plan concave changes to coincide with major maintenance operations on other areas to minimise the 35 cost of lost production due to the gyratory crusher being shut down. As removal and replacement of the concave liners is a time consuming, expensive and labour intensive operation, it is a routine aspect of maintenance to measure the degree of wear of the 3744800_1 (GHMtters) P88123.AU.2 3 concave liners to ensure that, while said liners are replaced when they have become suitably worn, they are not replaced too early and that the expected date on which they are replaced is compatible with productions plans. 5 The degree of wear in the concave liners is commonly measured by ultrasonic thickness testing, diameter measurement with convention measuring equipment such as tape measures or, by drilling holes in the spaces between the worn liners and measuring the lengths of the drill holes. All of these techniques are labour intensive and involve direct manual interaction within the cavity of the crusher. Before the 10 measurements can be performed, the crusher must be shut down and the cavity directly above the crusher cleared of residual feed material. Suitable work platforms must then be placed inside the crusher to ensure the safety of personnel entering the machine. 15 Measuring the worn state of the concave liners can also act as a means of determining the optimal time to change the mantle and/or the optimal mantle size to install. This is generally done 2-3 times during the life of each concave liner set. As the concave liners are very difficult to measure by conventional means while the mantle is in the crusher, measurements are normally performed with the mantle out of the machine. 20 However, it is necessary to prepare the replacement mantle before the previous mantle is removed, requiring the replacement mantle size to be selected before the concave liners can be measured to determine the replacement mantle's suitability. More recent developments have involved the use of laser scanning methods to 25 measure the concave liner shape. The methods can decrease the need to empty the pocket above the crusher and allow the operation to be performed quickly, but require highly skilled operators and expensive equipment. Substantial data processing is then required off-site once laser scanning is complete, resulting in delayed feedback regarding the suitability and degree of wear of the concave liners. 30 The present invention seeks to overcome at least some of the aforementioned disadvantages. The above references to the background art do not constitute an admission that the art 35 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 apparatus and method as disclosed herein. 3744860_1 (GHMatlers) P88123.AU.2 4 Summary of the Disclosure In a first aspect there is disclosed a liner assembly for indicating wear of a front face of 5 a liner for protecting an underlying surface, said liner assembly comprising: a liner for protecting an underlying surface from wear, the liner comprising a front face subject to wear; and, one or more indicators arranged to be disposed on a side of said liner, the one or more indicators being spaced from the front face by a distance corresponding, 10 respectively, to a predetermined degree of wear from the front face of the liner in an arrangement whereby, in use, exposure of one of the one or more indicators indicates the degree of wear from the front face of the liner. In one embodiment the liner comprises one or more markings disposed on the side of 15 said liner, the one or more markings being spaced from the front face by a distance corresponding, respectively to the predetermined degree of wear from the front face of the liner. The one or more indicators may be positioned, respectively, adjacent to the one or more markings whereby, in use, exposure of one of the one or more indicators indicates the degree of wear from the front face of the liner. 20 In another embodiment, the one or more markings comprise one or more grooves extending into the liner and underlying the front face. In this specific embodiment, the one or more indicators are arranged to be received, respectively, in the one or more grooves. 25 In one embodiment the one or more indicators provide respective visual indication of the degree of wear. In one form the one or more indicators may be colour-coded to indicate degree of 30 wear. In an alternative form the one or more indicators may be shaped and sized in a suitable manner to indicate degree of wear. For example, the one or more indicators may be triangular, trapezoid-shaped, or alternative suitable polygonal shapes. One 35 respective apex of the one or more indicators may be positioned in lateral alignment with respect to the front face of the liner in a manner wherein said apex is progressively and correspondingly worn with the front face of the liner, thereby 374480_1 (GHMatters) P88123.AU.2 5 presenting an exposed face of the indicator. A length of the exposed face of the indicator may be coded to indicate the degree of wear of the liner. In some forms of this specific embodiment the length of the exposed face of the indicator directly indicates the degree of wear of the liner in distance units (e.g. mm). In alternative 5 forms, the length of the exposed face of the indicator indicates the degree of wear of the liner in terms of the percentage wear of the liner or percentage of design efficiency of the liner and/or crusher. For example, exposure of 50 mm of the indicator may indicate 50 mm wear of the liner from the front wear face of the liner, or 50% wear of the liner, or 50% overall efficiency of the crusher at that level of wear, depending on 10 the manner in which the indicator is coded. In a second aspect there is disclosed a liner for protecting an underlying surface from wear, the liner comprising a front face subject to wear and one or more markings disposed on the side of said liner, the one or more markings being spaced from the 15 front face by a distance corresponding, respectively to the predetermined degree of wear from the front face of the liner. In one embodiment, the one or more markings comprise one or more grooves extending into the liner and underlying the front face. 20 In a third aspect there is disclosed a method of determining the degree of wear in a liner for protecting an underlying surface from wear, said method comprising: lining the underlying surface with a plurality of liner assemblies, wherein each liner assembly is as defined in the first aspect, and 25 inspecting the lined underlying surface to identify exposure of one of the one or more indicators, said exposure indicating the predetermined degree of wear from the front face of the liner. In one embodiment, said method further comprises the step of measuring a length of 30 an exposed surface of one of the one or more indicators, the length of the exposed surface directly corresponding to the degree of wear from the front face of the liner. In a fourth aspect there is disclosed a system of determining the degree of wear in the liners for protecting an underlying surface from wear, said system comprising: 3s a plurality of liner assemblies arranged, in use, to line the underlying surface, wherein each liner assembly is as defined in the first aspect, and a code correlating exposure of the one or more indicators, respectively, to the 37448601 (GHMattem) P88123.AU.2 6 degree of wear from the wear face of the liner. In another aspect there is disclosed a method of fabricating a liner for protecting an underlying surface from wear, said method comprising forming a liner having a front 5 face subject to wear and making one or more markings on a side of said liner, the one or more markings being spaced from the front face by a distance corresponding, respectively, to a predetermined degree of wear from the front face of said liner. In one embodiment the step of making one or more markings comprises drawing, io cutting such as with a laser, etching, milling, or grinding the one or more markings on the side of said liner. In one embodiment the step of forming said liner comprises casting one or more grooves in the side of said liner. Alternatively, the step of forming said liner comprises 15 milling, grinding or etching the one or more grooves in the side of said liner. In a further aspect there is disclosed a method of fabricating a liner assembly for indicating wear of a front face of a liner for protecting an underlying surface from wear, said method comprising: 20 providing a liner as defined in the second aspect, and positioning one or more indicators, respectively, adjacent to the one or more markings on said liner. In an alternative aspect there is disclosed a method of fabricating a liner assembly for 25 indicating wear of a front face of a liner for protecting an underlying surface from wear, said method comprising: providing a liner comprising a front face subject to wear; and, disposing one or more indicators on a side of said liner, the one or more indicators being spaced from the front face by a distance corresponding, respectively, 30 to a predetermined degree of wear from the front face of the liner in an arrangement whereby, in use, exposure of one of the one or more indicators indicates the degree of wear from the front face of the liner. In one embodiment the step of disposing one or more indicators on a side of said liner 35 comprises: disposing a removable template on the side of said liner, wherein the removable template has one or more markings spaced from the front face of said liner 3744880.1 (GHMatters) P88123.AU.2 7 by a distance corresponding, respectively to the predetermined degree of wear from the front face of the liner; positioning the one or more indicators adjacent to the one or more markings of the template; and s removing said template from the side of said liner. In a still further aspect there is disclosed a mould for casting a liner for protecting an underlying surface from wear, said mould being shaped to form a liner having a front face subject to wear and one or more grooves disposed in a side of said liner, the one 10 or more grooves extending into the liner and underlying the front face by a distance corresponding, respectively, to a predetermined degree of wear from the front face of said liner, said mould being provided with a back side that forms the front face of the liner and one or more protrusions, cores and/or blanks in a side thereof, wherein the one or more protrusions, cores and/or blanks are spaced from the back side of the 15 mould at a distance to provide, in use, one or more grooves in the liner cast therein, said one or more grooves corresponding, respectively, to the predetermined degree of wear of said liner. Description of the Figures 20 Notwithstanding any other forms which may fall within the scope of the liners and moulds therefor, liner assemblies, and methods and systems 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: 25 Figure 1 is a cut out view of a gyratory crusher showing a fixed outer shell assembly having a surface lined with a plurality of liners and an inner conical head; Figure 2 is a perspective view of a liner in accordance with one embodiment; 30 Figure 3a is a perspective view of a row of a plurality of liner assemblies and Figure 3b is a perspective view of the row of liner assemblies shown in Figure 3a when worn through use in a gyrator crusher, such as shown in Figure 1; 35 Figure 4 is a section view of two liners in accordance with another embodiment; Figures 5a and 5b are rear perspective views of two liners, respectively, in 3744880_I (GHMater) P88123 AU 2 8 accordance with an alternative embodiment; and Figure 6 is a side view of a liner assembly in accordance with a further alternative embodiment. 5 Detailed Description of a Specific Embodiment Embodiments of a liner and a liner assembly with particular (though not exclusive) reference for a conventional gyratory crusher will now be described by way of example 10 only. Referring to Figure 1 there is shown a cut out view of a conventional gyratory crusher 100 having a mantle 110 and a plurality of concave liners 120 arranged in tiered rows. 15 A concave liner 10 in accordance with one embodiment is shown in Figure 2. The concave liner 10 is a generally plano-concave block having a pair of opposing vertical side faces 12, an upper horizontal face 14, a lower horizontal face 16, a rear face 18 and a front face 20. Both the rear and front faces 18, 20 may be curved in a horizontal and a vertical aspect so that when a plurality of liners 10 is assembled in a series of 20 layered tiers, as shown in Figure 1, the layered tiers define a concave cylindrical form. The front face 20 may be considered as the wear face of the liner 10 since it bears the impact of material in the gyratory crusher 100 during a crushing operation and, consequently, will wear away over a period of time. 25 It will be appreciated that the shape and thickness of the concave liner 10 and the curvature of the rear and front faces 18, 20 of the concave liner 10 will vary amongst concave liners 10 used in the gyratory crusher 100, depending on the designated position of respective concave liners 10 within the gyratory crusher 100, such as whether they are located in a bottom, top or intermediate tiers of the outer shell of the 30 gyratory crusher 100. The rear face 18 of the liner 10 may be provided with a recess 22 therein. The purpose of the recess 22 is to receive a pourable curable backing material to affix the rear face 18 of the liner 10 to the outer shell. The recess 22 also lightens the overall 35 weight of the liner 10, particularly in areas where the liner 10 is not likely to wear before requiring removal. 3744860_1 (GHMatters) P8123.AU-2 9 The vertical side faces 12 of the liner 10 may be provided with a recess 24 for receiving a locking pin (not shown). A locking pin is commonly used in the installation of a plurality of liners 10 on the outer shell of the gyratory crusher 100 to facilitate regular spacing of the liners 10 in their respective tiered rows. Typically, the recess 24 s is tapered to receive the locking pin. In the embodiments shown in Figures 2 to 4, a single groove 26 may be disposed in the vertical side faces 12 of the liner 10. The single groove 26 extends continuously along the vertical side face 12 from the upper horizontal face 14 to the lower horizontal 10 face 16 of the liner 10. One or more grooves 28 may be disposed in the upper horizontal face 14 of the liner 10. Groove(s) 28 may be provided in the liner 10 in addition to groove(s) 26 or as an alternative to groove(s) 26. In the embodiment shown in Figures 2 to 4, a single 15 groove 28 extends continuously along the upper horizontal face 14 between the opposing vertical side faces 12 of the liner 10. The grooves 26 and 28 are spaced from the front face 20 of the liner 10 at a distance which corresponds to a degree of wear thereof. The degree of wear may be quantified 20 in absolute distance units from the front face 20 of the liner 10 (e.g. in mm) or percentage wear of the liner 10 from the front face 20 of the liner 10. For example, the single grooves 26, 28 may indicate the maximum degree of wear of the liner 10, at which point the liner 10 requires replacement. When the liner 10 is provided with more than one of groove 26 and/or groove 28, the grooves 26, 28 can be spaced, 25 respectively, to indicate varying degrees of wear such as 50% wear, 75% wear and 100% wear of the liner 10, for example. Although grooves 26, 28 will generally follow the curvature of the front face 20 of the liner 10, it will be appreciated that the spacing of the groove 26 from the front face 20 30 of the liner 10 may not be constant along the entire length of the groove 26, as the spacing may depend on the curvature of the front face 20 and the expected wear profile of the liner 10. The curvature of grooves 26, 28 and the desired spacing of the grooves 26, 28 from the front face 20 of the liner 10, to correspond with degree of wear of the liner 10, may be calculated with wear profile modelling techniques that are well 35 known to those skilled in the art. The desired spacing of the grooves 26, 28 from the front face 20 of the liner 10 may also correspond to a predetermined minimum thickness for the liner 10. 3744860_1 (GHMatters) P88123.AU.2 10 It will be appreciated that a primary purpose of the concave liners 10 is to provide a wear surface for the crusher 100. Additionally, however, embodiments of the concave liners 10 may be used in a concave liner assembly 30 for indicating wear in a crusher 5 100. Referring to Figures 3a, 3b and 4, there is shown a concave liner assembly 30. The concave liner assembly 30 includes a concave liner 10 and one or more indicators 32, 34 adapted to be received, respectively, in the one or more grooves 26, 28. The 10 concave liner assembly 30 is installed in the crusher 100 in a similar manner to a conventional liner. In use, however, exposure of one of the one or more indicators 32, 34, as shown in Figure 3b, indicates the degree of wear from the front face 20 of the concave liner 10 during its operational life. Consequent to the degree of wear of the concave liners 10 that is indicated by exposure of the indicators 32, 34, the crusher is may then undergo maintenance and one or more concave liners 10 may be removed and replaced. The indicator 32 comprises a strip. In one embodiment of the invention, the indicator 32 comprises a strip of resilient material, such as a foamed polymeric material, 20 synthetic rubber, or natural rubber. The indicator 32 may also facilitate regular spacing between adjacent concave liners 10 in tiered rows of the outer shell of the crusher 100. The resilient character of the indicator 32 contributes to sealing the joins between adjacent vertical faces 12 of adjacent concave liners 10 in tiered rows of the outer shell of the crusher 100, thereby minimising the need to use a sealant between adjacent 25 concave liners 10 and reducing labour requirements when the concave liners 10 are installed. The indicator 34 also comprises a strip, preferably of a polymeric material which is compression resistant. The indicator 34 is adapted to be received in the groove 28 on 30 the upper horizontal face 28 of the concave liner 10 and is thus subject to the load of an overlying concave liner in an adjacent upper tier. Advantageously, the indicator 34 may also facilitate regular spacing between concave liners 10 in adjacent tiered rows, thereby shortening the time required for installation of the liners 10 on the outer shell. 35 The concave liner assembly 30 may be fabricated by positioning one or more indicators, 32, 34, respectively, in the one or more grooves 26, 28 in the concave liner 10. The indicators 32, 34 may be positioned in the grooves 26, 28 with or without an 374480_1 (GHMatters) P88123.AU.2 I I adhesive, such as an epoxy or silicone adhesive. In one embodiment the indicators 32, 34 are brightly coloured so as to be readily visible when exposed. It is envisaged that when more than one indicator 32, 34 is 5 included in the concave liner assembly 30, that the indicators 32, 34 will have separate distinctive colours, and that the separate distinctive colours will be colour-coded to correspond to a degree of wear. For example, exposure of a blue indicator 32, 34 positioned in a groove 26, 28 corresponding to 50% wear of the concave liner 10 would indicate 50% wear of the concave liner 10, exposure of a green indicator 32, 34 10 positioned in a groove 26, 28 corresponding to 75% wear of the concave liner 10 would indicate 75% wear of the concave liner 10, and exposure of a red indicator 32, 34 positioned in a groove 26, 28 corresponding to 100% wear of the concave liner 10 would indicate 100% wear of the concave liner 10. is Referring now to Figures 5a and 5b, there is shown an alternative embodiment of a liner 10', where like features are denoted with like reference numerals throughout. In this particular embodiment, the liner 10' has a plurality of recesses 36 and protrusions 38 disposed in the vertical side faces 12 of the liner 10'. In use, the recesses 36 are arranged to receive complementary protrusions 38 of an adjacent liner 10'. 20 The recesses 36 and protrusions 38 may be arranged in an alternating spaced pattern extending along the vertical side faces 12 of the liner 10' as shown in Figure 5a. Alternatively, as shown in Figure 5b, a plurality of spaced protrusions 38 may be arranged to extend along the vertical side face 12 of the liner 10'. In this latter 25 embodiment, it will be appreciated that an adjacent liner 10' would be provided with a plurality of complementary recesses 36 configured to receive the protrusions 38 of the liner 10'. The recesses 36 and the protrusions 38 are spaced from the front face 20 of the liner 30 10' by a distance corresponding, respectively, to the predetermined degree of wear from the front face of the liner 10'. In use, the protrusions 38 may become visually apparent and thereby function as indicators of the degree of wear from the front face 20 of the liner 10'. 35 Location of the protrusions 38 in the complementary recesses 36 of an adjacent liner 10' may also assist with the installation of the liners 10' in the crusher 100. It will be appreciated that although the protrusions 38 and the recesses 36 may be shaped to 37448801 (GHMatters) P88123 AU 2 12 provide a snap lock fit or a friction fit therebetween it is preferred that the protrusions 38 and recesses 36 are shaped to provide a loose fit therebetween to facilitate ready location of adjacent liners 10' during installation and ready detachment of the liners 10' from one another during a replacement operation. 5 The protrusions 38 may be cast into the liner 10'. Alternatively, the protrusions 38 may be fabricated from a material that is the same or different from the liner 10' and subsequently adhered onto the vertical side face 12 of the liner 10' in the desired position. 10 Referring to Figure 6, there is shown an alternative concave liner assembly 30' where like features are denoted with like reference numerals throughout. The concave liner assembly 30' includes a concave liner 10 and one or more indicators 32' disposed on respective vertical sides 12 of the concave liner 10. The concave liner assembly 30' is is installed in the crusher 100 in a similar manner to a conventional liner. In use, however, exposure of one of the one or more indicators 32', as shown in Figure 6, indicates the degree of wear from the front face 20 of the concave liner 10 during its operational life. 20 The indicator 32' comprises a triangular element having opposing side faces 40, wherein said side faces 40 are arranged, in use, to be contiguously fixed to respective vertical sides 12 of adjacent concave liners 10. The concave liner assembly 30' may be fabricated by positioning one or more indicators, 32' on the vertical sides 12 of the concave liners 10, with or without an adhesive such as epoxy or silicone adhesive. 25 The indicators 32' may be formed from resilient materials for similar reasons as has been described above, or from materials with a similar wear capacity as the liner 10. Generally, the indicators 32' will be formed from materials which are a different colour from the liner 10 so that exposure of the indicator 32' can be readily visually ascertained. 30 Each triangular element is disposed with respect to the front face 20 of the concave liner 10 such that an upper vertex 42 and a lower vertex 44 of the triangular element are in parallel longitudinal alignment with a rear face 18 of the liner 10 and a third vertex 46 extends laterally toward the front face 20. Additionally, the upper and lower 35 vertices 42, 44 of the triangular element are positioned, respectively, at a distance from the front face 20 of the liner 10 that is substantially the same as the distance between the upper and lower vertices 42, 44. It will be appreciated that the vertical sides 12 of 3744880_1 (GHMatters) P88123.AU.2 13 the liner 10 may be provided with suitable markings for accurate positioning of the indicator 32'. In use, as the front face 20 of the liner 10 undergoes wear, the third vertex 46 the 5 triangular indicator 32' is progressively and correspondingly worn, thereby presenting an exposed face 48 of the indicator 32'. Consequently, the triangular indicator 32' is sized such that the vertical length of the exposed face 48 indicates the degree of wear of the liner 10. For example, the triangular indicator 32' may be sized and positioned with respect to the front face 20 of the liner 10 such that when the vertical length of the 10 exposed face 48 of the indicator 32' is 4 mm, then the degree of wear of the liner 10 from the front face 20 corresponds to 4mm. Similarly, when the vertical length of the exposed face 48 of the indicator 32' is 20 mm, then the degree of wear of the liner 10 from the front face 20 corresponds to 20 mm. 15 Accordingly, by employing this particular embodiment, the degree of wear of the liner 10 in distance units (e.g. mm) may be directly measured by measuring the vertical length of the exposed face 48 of the indicator 32'. It will be appreciated that more than one indicator 32' may be located at intervals along the side 12 of the concave liner 10, as shown in Figure 6. 20 Alternatively, the length of the exposed face 48 of the indicator 32' may indicate the degree of wear of the liner in terms of the percentage wear of the liner 10 or percentage of design efficiency of the liner 10 and/or crusher. For example, exposure of 50 mm of the indicator 32' may indicate 50 mm wear of the liner 10 from the front 25 wear face of the liner 10, or 50% wear of the liner 10, or 50% overall efficiency of the crusher at that level of wear, depending on the manner in which the indicator is coded. It will be appreciated that if the indicators 32' are coded to indicate percentage wear of the liner 10, then the sides extending between the vertices 42, 44, 46 may be curved 30 and may taper outwardly towards vertices 42, 44. In the embodiment where the indicators 32' are used to indicate percentage efficiency, the vertex 46 may be positioned rearwardly and the vertices 42, 44 may be positioned forwardly. Various embodiments of the concave liners 10, 10' may be fabricated from metallic 35 materials capable of functioning as a wear surface under the operation conditions typically experienced in a crusher. Suitable metallic materials include, but are not limited to, manganese ferrous alloys, such as manganese steel. Such metallic 374458601 (GHMatters) P88123AU.2 14 materials are generally capable of being cast in moulds. Accordingly, embodiments of the concave liners 10, 10' may be fabricated by casting the metallic material in an appropriately shaped mould. The mould may be provided 5 with: one or more protrusions; cores; and/or blanks to create the grooves 26, 28 in the liner 10. Alternatively, the mould may be provided with one or more protrusions, cores, and/or blanks to create the recesses 36 and protrusions 38 in the liner 10'. The location and configuration of the protrusions, cores and/or blanks is dependent on the desired wear indication to be provided and can be calculated as described above, with io reference to wear profile modelling techniques. Numerous variations and modifications will suggest themselves to persons skilled in the relevant art, in addition to those already described, without departing from the basic inventive concepts. All such variations and modifications are to be considered within 15 the scope of the present invention, the nature of which is to be determined from the foregoing description. 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 20 "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 of the liners and moulds therefor, liner assemblies, systems and methods as disclosed herein. 374488O_1 (GHMatters) P85123.AU 2

Claims (22)

1. A liner for protecting an underlying surface from wear, the liner comprising a front face subject to wear and one or more markings disposed in a lateral side of the liner adjacent to the front face, the one or more markings being spaced from the front face by a 5 distance corresponding to a predetermined degree of wear from the front face of the liner.

2. The liner according to claim 1, further comprising one or more indicators positioned, respectively, adjacent to the one or more markings whereby, in use, exposure of one of the one or more indicators indicates the predetermined degree of wear from the front face of the liner. 10

3. The liner according to claim 1 or claim 2, wherein the one or more markings comprise one or more grooves extending into the liner and underlying the front face.

4. The liner according to claim 3 when depending from claim 2, wherein the one or more indicators are arranged to be received, respectively, in the one or more grooves.

5. The liner according to any one of claims 1 to 4, wherein the lateral side in which 15 the markings are disposed is a side face and/or an end face.

6. A liner assembly for indicating wear of a front face of a liner for protecting an underlying surface, the liner assembly comprising: a liner for protecting an underlying surface from wear, the liner comprising a front face subject to wear, a rear face opposed to the front face, and lateral sides extending 20 between the front face and the rear face; and, one or more indicators arranged to be disposed on the lateral sides of the liner, the one or more indicators being spaced from the front face by a distance corresponding, respectively, to a predetermined degree of wear from the front face of the liner in an arrangement whereby, in use, exposure of one of the one or more indicators indicates the 25 degree of wear from the front face of the liner.

7. The liner assembly according to claim 6, wherein the one or more indicators are shaped and sized in a suitable manner to indicate the degree of wear, whereby a length of an exposed face of the one or more indicators indicates the degree of wear of the liner. 16

8. The liner assembly according to claim 7, wherein the length of the exposed face of the one or more indicators directly indicates the degree of wear of the liner as measured in distance units (mm), percentage wear, or percentage efficiency of the liner and/or crusher. 5

9. The liner assembly according to any one of claims 6 to 8, wherein the one or more indicators are triangular and a respective apex of the one or more triangular indicators are positioned in lateral alignment with respect to the front face of the liner in a manner wherein the apex is progressively and correspondingly worn with the front face of the liner, thereby presenting an exposed face of the indicator.

10 10. The liner assembly according to any one of claims 6 to 9, wherein the one or more indicators are colour-coded to indicate degree of wear of the liner.

11. The liner assembly according to any one of claims 6 to 10, wherein the one or more indicators comprise a resilient material.

12. The liner assembly according to claim 11, wherein the one or more indicators 15 comprise a foamed polymeric material, synthetic rubber or natural rubber.

13. The liner assembly according to any one of claims 6 to 12, wherein the one or more indicators are spaced from the rear face.

14. The liner assembly according to any one of claims 6 to 13, wherein the one or more indicators project outwardly from the lateral face, in use, being arranged to facilitate 20 regular spacing between adjacent liners when installed on the underlying surface.

15. The liner assembly according to claim 14, wherein each of the indicators is arranged, in use, to engage neighbouring lateral faces of two adjacently located liners.

16. The liner assembly to any one of claims 6 to 15, wherein the lateral sides in which the markings are disposed comprise a side face and/or an end face. 25

17. A method of fabricating a liner for protecting an underlying surface from wear, the method comprising forming the liner having a front face subject to wear and making one or more markings on a lateral side of the liner adjacent to the front face, the one or more 17 markings being spaced from the front face by a distance corresponding, respectively, to a predetermined degree of wear from the front face of the liner.

18. The method of claim 17, wherein the step of making one or more markings comprises drawing, cutting such as with a laser, etching, milling, or grinding the one or 5 more markings on the lateral side of the liner.

19. The method according to claim 17, wherein the step of forming the liner comprises casting one or more grooves in the lateral side of the liner.

20. The method according to claim 17, wherein the step of forming the liner comprises milling, grinding or etching one or more grooves in the lateral side of the liner. 10

21. A method of fabricating a liner assembly for indicating wear of a front face of a liner for protecting an underlying surface from wear, the method comprising: providing a liner comprising a front face subject to wear, a rear face opposed to the front face, and lateral sides extending between the front face and the rear face; and, disposing one or more indicators on the lateral sides of the liner, the one or more is indicators being spaced from the front face by a distance corresponding, respectively, to a predetermined degree of wear from the front face of the liner in an arrangement whereby, in use, exposure of one of the one or more indicators indicates the degree of wear from the front face of the liner.

22. The method according to claim 21, wherein the step of disposing one or more 20 indicators on a side of the liner comprises: disposing a removable template on the lateral side of the liner, wherein the removable template has one or more markings spaced from the front face of the liner by a distance corresponding, respectively to the predetermined degree of wear from the front face of the liner; 25 positioning the one or more indicators adjacent to the one or more markings of the template; and removing the template from the side of the liner.