WO2015105798A1

WO2015105798A1 - Wear member

Info

Publication number: WO2015105798A1
Application number: PCT/US2015/010327
Authority: WO
Inventors: Adam M. JONES
Original assignee: Esco Corporation
Priority date: 2014-01-07
Filing date: 2015-01-06
Publication date: 2015-07-16
Also published as: US20150191899A1

Abstract

A wear part for surfaces exposed to abrasive material. The wear part is particularly well suited for use on earth working equipment used in environments where dead bedding material is possible. The wear part in the form of a wear runner has stops to cause material to dead bed and at least one ramp to minimize the wear caused by the dead bed material.

Description

WEAR MEMBER

RELATED APPLICATION

[01] This application claims priority benefits to U.S. Provisional Patent Application No.

61/924575 filed January 7, 2014 which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

[02] The present invention pertains to a replaceable wear element for protecting an underlying surface of earth working equipment from abrasive earthen material.

BACKGROUND OF THE INVENTION

[03] In mining and construction, wear parts, often called wear runners, are commonly provided along the faces of excavating equipment that engage abrasive material. The wear part protects the underlying equipment from undue wear and extends the life of the excavating equipment.

[04] Typically the wear parts have a leading edge that initially contacts the abrasive material and a top surface over which the abrasive material travels as the excavating equipment engages the abrasive material. The movement of the abrasive material on the top surface wears the wear part such that the wear part needs replacement. The wear parts are often replaced a number of times due to the highly abrasive environment in which they are used. The wear parts may be welded to the excavating equipment, or the wear part may have multiple pieces such as a base that is secured to the excavating equipment and a wear member that is mechanically attached to the base.

[05] In some cases, earthen material can be used to protect the wear parts and extend the life of the wear parts. As the wear parts travel through the material to be excavated, the material is encouraged to pile up and stick to portions of the wear part. As the earthen material builds up it covers portions of the wear part to act as an additional wear surface. This technique is known as dead bedding. Dead bedding can extend the useful life of a wear part with less cost than increasing the thickness of the wear part, and is generally lighter than the metal used for the wear part. Dead bedding is also desirable because, should the material be worn or washed away, new material will be built up to replace the displaced material. In many cases, to get material to dead bed, a tumble bar in the front of the excavating equipment and an abutment surface in the rear of the excavating equipment is used.

[06] As one example, wear runners or wear parts 13a may be used inside a dipper bucket 3 (Figure 3 and 4). The dipper bucket 3 may be equipped with one or more tumble bar(s) 18 at the front end of the bucket to encourage the material to tumble over the wear parts 13a (Figure 3). Encouraging the material to tumble causes the material to generally create impact forces on the wear parts and minimizes the frictional wear on the top surfaces of the wear parts. In another example, a bucket 3 may not be provided with a tumble bar at the front of the bucket and the wear parts 13a may be arranged in a straight line across the front of the bucket so that the leading edge 25a of the wear parts 13a acts as a tumble bar (Figure 4). The rear of the bucket may be equipped with another tumble bar or rear abutment surface 20 to stop the material from tumbling (Figure 3). As the material contacts the rear abutment surface 20 the material builds up in a forward direction (i.e., toward the direction of the flow of the material into the bucket as indicated by arrow 22). The material builds up and covers some of the wear parts between the rear abutment surface 20 and the front tumble bar 18. Material properties (e.g., material angle of repose) determines how far forward the material will build up over the wear parts. The top surface on the wear parts not protected with earthen material experience wear as the excavating equipment continues to dig. To reduce the weight of each wear part 13a and minimize the top surface that experiences wear on the wear part, each wear part may have recess 31a and/or a cavity 33a (Figure 4a) for earthen material to collect within the wear part and between wear parts arranged in a pattern 28, 28a as shown in Figures 3 and 4. Eventually, as the excavating equipment continues to dig the front tumble bar 18 or the leading edge 25a of the wear parts 13a and the rear abutment surface 20 wear causing the earthen material over the wear parts to be worn away and lost. As the earthen material over the wear parts is lost all of the wear parts begin to be exposed and wear. The generally flat top surface of the wear part causes the entire top surface of the wear part to experience frictional wear. The frictional wear on the top surface causes the wear parts to be worn and need replacement prematurely. SUMMARY OF THE INVENTION

[07] The present invention pertains to a wear part for surfaces exposed to abrasive material.

The wear part is particularly well suited for use on earth working equipment used in environments where dead bedding material is possible.

[08] In one aspect of the invention, the leading surface is inclined forward such that the wear part has an included angle of less than 90 degrees between the leading edge and the attachment surface to encourage dead bedding as well as cause material tumble. Alternatively, the leading surface and the trailing surface may both be inclined so as to have an included angle of less than 90 degrees between the leading edge and the attachment surface and between the trailing edge and the attachment surface to encourage dead bedding as well as cause material tumble regardless of whether the leading edge faces the flow of material or the trailing edge faces the flow of material (or whether the material flows alternatively in either direction). In one preferred construction, the included angle is greater than about 50 degrees to lessen the hydraulic lift effect the material may impose on the wear part (i.e., to lift it from the attachment surface) and less than about 85 degrees to better capture the material between adjacent wear parts, although other inclinations outside the preferred range can be used.

[09] In another aspect of the invention, the wear part generally tapers (i.e., narrows) from the leading end to the trailing end. Generally tapering the wear part from the leading end to the trailing end discourages the dead bed material from washing away or scouring the wear part, provides a ramp to create a skip effect (i.e., protecting areas rearward of the leading end of the wear part when the trailing end faces the flow of material), allows the wear part to wear more slowly (i.e., only the leading edge of the top surface of the wear part is exposed once the wear part begins to experience wear), and reduces the amount of throw away material once the wear part needs replacement.

[10] In another aspect of the invention, the wear part has a raised trailing end. The raised trailing end gives the wear part a rear abutment surface and allows the wear part to dead bed itself (i.e., without other bars or parts capturing the earthen material to overlie the wear parts). [11] In another aspect of the invention, the trailing end of the wear part is provided with a ramp. In one preferred construction, the ramp is inclined away (i.e., rearward) from the trailing end. The ramp creates a skip effect protecting areas rearward of the upper end of the ramp when the lower end of the ramp faces the flow of material. This inclination can, then, also work more effectively as a leading end if the material flow is reversed.

[12] In another aspect of the invention, the wear part is provided with a lifting eye spaced from the attachment surface without extending above the top surface of the wear part. Locating the lifting eye away from the attachment surface allows rigging to remain attached to the wear part until the wear part is fully installed. Also, locating the lifting eye so that it does not extend above the top surface of the wear part allows material to flow over the wear part without disrupting the flow of material over the wear part.

BRIEF DESCRIPTION OF THE DRAWINGS

[13] Figure 1 is a side view of a cable shovel.

[14] Figure 2 is a perspective view of cable shovel bucket.

[15] Figure 3 is a perspective view of a cable shovel bucket with prior art wear parts and tumble bars secured to a wall of a bucket. The door, rear wall, teeth, and other details of the bucket are omitted to simplify the drawing.

[16] Figure 4 is a perspective view of the bucket shown in Figure 3 with prior art wear parts secured to a wall of a bucket in a pattern that varies from the pattern shown in Figure 4.

[17] Figure 4a is a perspective view of the wear part shown in Figures 3 and 4.

[18] Figure 5 is a top view of a wear part in accordance with the present invention.

[19] Figure 6 is a cross section of the wear part in Figure 5 taken along lines 6-6 in Figure 5.

[20] Figure 7 is a bottom view of the wear part in Figure 5.

[21] Figure 8 is a side view of the wear part in Figure 5.

[22] Figure 9 is a bottom perspective view of the wear part in Figure 5 secured to a base. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[23] The present invention pertains to a wear part for protecting a surface that experiences wear and handles material that is suitable for dead bedding. The present invention is particularly well suited for use on various kinds of earth working equipment including, for example, excavating equipment and ground conveying equipment. Excavating equipment is intended as a general term to refer to any of a variety of excavating machines used in mining, construction and other activities, and which, for example, include dozers, loaders, dragline machines, cable shovels, face shovels, and hydraulic excavators. Excavating equipment also refers to the ground-engaging components of these machines such as the bucket. Ground conveying equipment is also intended as a general term to refer to a variety of equipment that is used to convey earthen material and which, for example, includes chutes and mining truck beds. For convenience of discussion, the wear part is discussed in terms of a wear member for protecting a surface on a cable shovel bucket; however, the wear member may be used to protect surfaces of other earth working equipment.

[24] Relative terms such as front, rear, top, bottom and the like are used for convenience of discussion. The terms front or forward are generally used to indicate the usual direction of travel during use (e.g., while digging), and upper or top are generally used as a reference to the surface over which the material passes when, for example, it is gathered into the bucket. Nevertheless, it is recognized that in the operation of various earth working machines the wear member may be oriented in various ways and move in all kinds of directions during use. Further, the earthen material may flow in more than one direction. For example, in the example of some excavating machines the earthen material will flow into the bucket during digging and in the opposite direction when dumped from the bucket.

[25] A cable shovel 1 is equipped with a bucket 3 for gathering earthen material 2 while digging (Figure 1). The bucket 3 includes a frame or shell 4 defining a cavity 16 for gathering material during the digging operation (Figure 2). Shell 4 may include a rear wall 6 having attachment supports 8 to attach the bucket 3 to earth working equipment, a front wall 10 opposite the rear wall 6, and a pair of opposing sidewalls 14 each located between the rear wall 6 and the front wall 10. A door 12 is hinged to rear wall 6 so as to be closed during digging and define the bottom wall of the bucket, and opened during dumping. Multiple configurations of buckets are known and variations in bucket geometry exist. The drawings illustrate one example for explanation of the various inventive features of the present invention. Moreover, other kinds of excavating machines will have different kinds of buckets. For example, in a dragline bucket the front and top are typically open, or in a hydraulic excavator there is no door. The specific geometry of the bucket is not intended to be limiting as the present invention can be used with various types of buckets and in non-bucket applications (e.g., truck trays). In the drawings, the bucket 3 has a lip 5 that extends forward of the front wall 10 and is the digging edge of the bucket 3 (Figures 2). The digging edge is that portion of the equipment that leads the contact with the ground. Multiple tooth assemblies 7 and shrouds (not shown) are often secured to the digging edge to protect the edge and break up the ground ahead of the lip 5.

[26] In accordance with the invention, wear member 13 has a leading surface 15, a trailing surface 17, a top surface 19 to engage earthen material and protect the underlying equipment, an attachment surface 21 to secure the wear member 13 to excavating equipment, and a pair of side surfaces 23 extending between the top surface 19 and the attachment surface 21 (Figures 5-9). Both the leading surface 15 and the trailing surface 17 have an included angle Θ, and θ' that is preferably less than 90 degrees between the leading surface 15 or the trailing surface 17 and the mounting surface (i.e., the surface to be protected) of the earth working equipment. In the preferred construction, the attachment surface 21 follows the mounting surface though other arrangements are possible. The leading and trailing surfaces 15, 17 can act as a tumble bar to cause earthen material to tumble across the wear member 13 regardless of whether the leading surface 15 faces the flow of material or the trailing surfaces 17 faces the flow of the material. In this way the wear member forms a tumble bar feature regardless of whether the wear part is attached with the leading surface or the trailing surface facing in opposition to the flow of the material, or if the earthen material flows in two directions such as the inner bottom wall of a dragline bucket. The included angle θ' of the trailing surface 17 may or may not equal the included angle Θ of the leading surface 15. In one preferred embodiment, the included angle Θ and θ' is each greater than about 50 degrees. The included angle is preferably greater than about 50 degrees to lessen the hydraulic lift effect on the wear part as the material being excavated encounters the leading or trailing surface but could in certain circumstances be less than 50 degrees. While it is preferred that both Θ and θ' to be less than 90 degrees, it is possible for either or both Θ and θ' to be equal to or greater than 90 degrees. Leading surface 15 and trailing surface 17 are preferably generally planer. However, the leading surface 15 and trailing surface 17 may have other shapes, (for example, curved inward or outward, segmented, irregular) such that only part of the leading (or trailing) surface is at an angle between the leading edge 25 (or trailing edge 27) of the wear member 13 and the leading edge 26 (or trailing edge 29) of the attachment surface 21 that is less than 90 degrees.

[27] Similar to wear members 13a, leading surface 15, trailing surfaces 17, and side surfaces 23 may have recesses 31. When multiple wear members 13 are attached to a bucket or truck tray, recesses 31 create pockets that allow material to build up between the wear members located to the sides of each wear member, in front of each wear member, and rearward of each wear member. Wear members 13 may be arranged in a pattern similar to the patterns 28 and 28a shown in Figures 3 and 4 or may be arranged in a completely different pattern depending on the earth working application that the wear member 13 is being used in.

[28] Similar to wear members 13a, top surface 19 may have one or more cavity or pocket 33 to collect earthen material. The presence of a cavity or cavities lessens the material usage and weight of the wear member, and better collects and maintains earthen material. Nevertheless, cavity 33 could be omitted. The cavity 33 may be rectangular, elliptical or any other shape. A hole 35 may extend between the cavity 33 and the attachment surface 21. Hole 35 generally matches the shape of a lock 37 used to secure the wear member 13 to a base 39 fixed to excavating equipment (as shown in Figure 6, 7, and 9). Other bases, locks and holes could be used (as discussed below). In alternative embodiments (not shown), wear member may be welded to a base or welded directly to the excavating equipment without the use of a lock. The weld-on wear members can be identical to what is shown (e.g., with hole 35) so only one form of part need be made and/or stored, or it can be made without the hole and/or other changes (such as weld recesses) to better accommodate welding to the attachment surface.

[29] The use of an inclined leading (or trailing) surface with the pockets and other features of the wear member tend to cause the material to stay within the pockets formed within and between the wear members for effective dead bedding. In one preferred embodiment the included angle Θ and θ' is less than about 85 degrees to maximize the amount of material that is captured and maintained within the pockets.

[30] Wear member 13 is generally tapered (i.e., gradually narrows) from the leading edge 25 to the trailing edge 27. As seen in Figure 6, top surface 19 is inclined to slope downward toward trailing surface 17. This narrowing could be continuous or discontinuous, and could be uniform or changing. The taper and the cavity 33 discourages the dead bed material from washing away or scouring the wear member. The taper also provides a ramp if the material is flowing in the opposite direction (i.e., where the trailing surface 17 faces opposite to the flow of the earthen material), to create a skip effect or shadow where material flows up and off the ramp and avoids a section of the underling excavating equipment. The inclination of top surface 19 (i.e., the narrowing of the wear member) also enables the use of a raised portion 41 with an abutment surface 43 (as discussed below) that is generally at about the same height as the leading surface 15 to improve the flow of the material over the wear member. Nevertheless, the raised portion could be higher or lower than the leading surface or could be omitted completely. The taper along with abutment surface 43 encourages the build up of earthen material and increases the thickness of the earthen material over portions of the wear member instead of using metal to increase the thickness of the wear member. This reduces the weight of the wear member, reduces the cost of the wear member, and reduces the throw away material once the wear member has been completely worn.

[31] The wear member usually begins to wear initially along the leading edge 25 (i.e., along the intersection of leading surface 15 and top surface 19). Because the leading edge of the wear member 13 is initially exposed to wear, a portion of the leading surface 15 adjacent the leading edge 25 and a portion of the top surface 19 adjacent the leading edge 25 may be overlaid with a hardfacing material or made from a material having different properties than adjacent sections of the wear member (not shown) to extend the life of the wear member. Hardfacing and/or varying types of material may, of course, be provided at other locations of the wear member. The hardfacing may be, for example, tungsten carbide or spherical carbide.

[32] Wear member 13 preferably includes a raised portion 41 adjacent the inclined top surface 19. The raised portion 41 projects above the top surface 19 and provides an abutment surface 43 to stop the tumbling of the earthen material and cause the material to dead bed the cavity 33, recesses 31, and the top surface 19 of the wear member 13. The wear member 13 is preferably also provided with an abutment surface 43' at the front end of cavity 33 so that the wear member 13 can cause material to build up regardless of whether the trailing surface 17 or the leading surface 15 faces into the flow of material.

[33] A ramp 45 may be provided adjacent the trailing surface 17 of the wear member. The ramp 45 is preferably inclined upward and away from the trailing edge 27, as shown in Figures 5-9, but may be inclined in the opposite direction (not shown). Like the taper of the wear member, the ramp 45 creates a skip effect protecting areas rearward of the upper edge 47 of the ramp 45 when the lower edge 49 of the ramp 45 faces the flow of material. Like leading edge 25, the surfaces adjacent the upper edge 47 of ramp 45 may be overlaid with hardfacing or made from a material having different properties than adjacent sections of the ramp to extend the life of ramp 45.

[34] Wear member 13 may be provided with a lifting eye 51 to ease handling during installation. Lifting eye 51 is preferably spaced from the attachment surface 21 to ease coupling and decoupling of the hook or other connection means, and preferably does not protrude above a plane extending along the top surface 19 of the wear part 13 to improve the flow of material over the wear members. The lifting eye 51 may be located within the recess 31 in leading surface 15 and be located adjacent the leading edge 25. Locating the lifting eye 51 away from the attachment surface 21 allows rigging (not shown) to remain attached to the wear member 13 until the wear part is fully installed. The location of the lifting eye allows material to flow over the wear member without disrupting the flow.

[35] Attachment surface 21 may have a cavity 53 for accepting a base 39 that is secured to the excavating equipment. Cavity 53 generally matches the shape of base 39 (See Figure 9). The cavity may have dovetails and recesses that mate with dovetails on the base, such as disclosed in US Patent RE. 33,454, which is incorporated herein by reference. The cavity 53 may have reversible dovetails 55 and recesses 57 so that wear member 13 can be mounted on base 39 in either direction, such as disclosed in US Patent 5,063,695 which is incorporated herein by reference. Cavity 53 may be provided with projections 59 for engaging the base 39 and/or lock 37 as disclosed in US Patent 5,241, 765, which is incorporated herein by reference.

[36] Base 39 may be generally rectangular and have dovetails 61 that correspond to dovetails 55 on the wear member 13. A hole 63 that aligns with the hole 35 in the wear member 13, when the wear member is installed on the base, may extend through the base to accept a lock 37 to secure the wear member to the base. The base 39 may have recesses (not shown) that correspond to projections 59 on wear member 13. The base may be welded or otherwise secured to the excavating equipment. For example, the base may be welded to front wall 10 of bucket 3 and wear member 13 may be installed on base 39. Alternatively, the wear member may be welded to the earth working equipment with or without the use of a base.

[37] Lock 37 generally corresponds to the shape of hole 35 in wear member 13 and hole 63 in base 39. The lock, for example, may have a body and a resilient member as disclosed in US Patent 5,241,765 or US Patent 7, 144,183which are each incorporated herein by reference.

[38] Although the above discussion has discussed the invention in connection with a wear member for use on a cable shovel bucket, the wear member can be used on various types of buckets, for example, dragline buckets, hydraulic face shovel buckets, excavator buckets, and loader buckets. Moreover, a wear member of the present invention can also be used to dead bed material and protect the underlying surface on other kinds of earth working equipment such as chutes or truck trays or non-earth working equipment such as grain elevators. Although the wear member are disclosed in this application primarily in the context of wear runners, the inventive concepts could be incorporated into other kinds of wear parts.

[39] The above disclosure describes specific examples of a wear member for use with earth working equipment. The wear member includes different aspects or features of the invention. The features in one embodiment can be used with features of another embodiment. The examples given and the combination of features disclosed are not intended to be limiting in the sense that they must be used together.

Claims

CLAIMS:

1. A wear member for earth working equipment, the wear member comprising a leading surface facing a primary direction of a flow of earthen material over the wear member, a trailing surface generally opposite the leading surface, a top surface to engage the earthen material and protect the earth working equipment, and an attachment surface to secure the wear member to a mounting surface of the earth working equipment, wherein the leading surface forms an included angle of less than 90 degrees to the mounting surface to cause the earthen material to dead bed on the earth working equipment.

2. A wear member for earth working equipment, the wear member comprising a leading surface facing a primary direction of a flow of earthen material over the wear member, a trailing surface generally opposite the leading surface, a top surface extending generally between the leading surface and the trailing surface to engage the earthen material and protect the earth working equipment, an attachment surface to secure the wear member to earth working equipment, and a raised end projecting above the top surface adjacent the trailing surface, wherein the raised end includes an abutment surface generally facing the primary direction of flow of earthen material over the wear member to cause the earthen material to dead bed on the wear member forward of the abutment surface.

3. A wear member in accordance with claims 1 or 2 wherein the wear member has a thickness that generally narrows from the leading surface to the trailing surface.

4. A wear member for earth working equipment, the wear member comprising a leading surface facing a primary direction of a flow of earthen material over the wear member to cause the earthen material to dead bed on the earth working equipment, a trailing surface generally opposite the leading surface, a top surface to engage the earthen material and protect the earth working equipment, and an attachment surface to secure the wear member to a mounting surface of the earth working equipment, wherein the wear member generally narrows from the leading surface to the trailing surface.

5. A wear member in accordance with claims 1 or 4 wherein the wear member has a raised end projecting above the top surface adjacent the trailing surface, wherein the raised end includes an abutment surface generally facing the primary direction of flow of earthen material over the wear member so that the abutment surface dead beds the wear member forward of the abutment surface.

6. A wear member in accordance with claim 2 or 5 wherein the raised end includes a ramp inclined away from the trailing end in a direction toward the leading end.

7. A wear member in accordance with any one of the preceding claims wherein the trailing surface forms an included angle of less than 90 degrees to the mounting surface.

8. A wear member in accordance with any one of the preceding claims wherein the included angles formed by the leading surface and by the trailing surface are each less than about 85 degrees.

9. A wear member in accordance with any one of the preceding claims wherein the included angles formed by the leading surface and by the trailing surface are each greater than about 50 degrees.

10. A wear member for earth working equipment, the wear member comprising a leading surface facing a primary direction of a flow of earthen material during use of the earth working equipment, a trailing surface facing in a direction generally opposite the leading surface, a top surface extending generally between the leading surface and the trailing surface, an attachment surface to secure the wear member to earth working equipment, and an abutment above and rearward of the top surface, the abutment including a ramp inclined down and away from the leading surface.

11. A wear member in accordance with any one of the preceding claims wherein the leading surface generally creates a skip effect for the earthen material rearward of the leading surface.

12. A wear member in accordance with any preceding claims including a lifting eye spaced from the attachment surface.

13. A wear member in accordance with claim 12 wherein the lifting eye extends no higher than the top surface.

14. A wear member for earth working equipment, the wear member including a leading surface facing a primary direction of a flow of earthen material during use of the earth working equipment, a trailing surface, and a top surface extending generally between the leading surface and the trailing surface, an attachment surface to secure the wear member to earth working equipment, and a lifting eye that extends no higher than the top surface.

15. A wear member in accordance with claim 14 wherein the top surface is inclined so that the wear member generally narrows from the leading surface toward the trailing surface.

16. A wear member in accordance with claim 14 or 15 including an abutment above and rearward of the top surface.

17. A wear member in accordance with any one of claims 14-16 wherein the abutment includes a ramp inclined downward away from the leading surface.

18. A wear member in accordance with any one of the preceding claims wherein the top surface includes at least one cavity for collecting the earthen material.

19. A wear member in accordance with any one of the preceding claims wherein at least a portion of the wear member is overlaid with a hardfacing material.

20. A wear member in accordance with any one of the preceding claims wherein the leading surface is planer.

21. A wear member in accordance with any one of the preceding claims wherein the attachment surface defines a cavity to engage a base secured to the earth working equipment.

22. A wear member in accordance with any one of the preceding claims including a hole to receive a lock to secure the wear member to the earth working equipment.