OA17051A - Wear assembly. - Google Patents

Abstract

A wear assembly with strain relief protects exposed surfaces of excavating equipment such as a bucket lip. Wear components may include a seat where loads are applied; welding flanges flanking the seat on opposite ends of the component welded to the equipment, and strain relief areas between each welding flange and the seat. The strain relief balances stresses from loading in the wear assembly across the weld flange to limit cracking from stress concentrations. Strain relief may include modification of material properties or modification of component configuration to reduce stiffness of the component between the weld flanges and the seat.

Description

WEAR ASSEMBLY

Cross-Reference to Related Application [0001] The présent application claims prlorlty to U.S. Provisional Application No. 61/600,437, filed February 17, 2012, which application Is Incorporated by reference herein In Its entlrety and made part hereof.

Fleldofthe Invention [0002] This Invention relates to various wear members and wear assemblies for use with earth moving equipment.

Background of the Invention [0003] Excavating buckets and other earthmoving equipment are subjected to harsh conditions Including abrasive materials, extreme loads and cydic stresses and strains. Various wear members and wear assemblies are attached to llps, other dlgging edges and surfaces to protect them from wear and érosion. The wear assemblies extending from the digglng edges and surfaces expérience high Internai stresses during operation which can resuit in failure of the components. The wear assemblies require adéquate strength to avoid failure, but also hâve to Incorporate ductlllty in order to transfer applied loads across a broad support structure without excessive stress concentrations at crltical points. Fatigue due to cyclic loadlng combined with concentration of stress within locallzed areas of the components can cause reduced service llfe or catastrophlc failure in the wear assembly.

5ummarvof the Invention [0004] Wear members for minlng and other earthmoving equipment are sacrifidal components that are frequently replaced. They overlle the lips or other surfaces of excavatlng buckets and other earthmoving equipment that would otherwlse be 5 exposed and in contact with the ground. Excavated materials are abrasive and the wear members can be wom away qulckly. The loads applied to the wear members during dlgglng are varled and include, for example, axial, vertical and side loads. The loads corne In various forms such as impact, vibration and reverse loads.

[0005] Minlng and excavation equipment can move tons of materials In a single cycle. These large loads requlre components that can absorb and withstand the applied stresses. Stress within the components can be extreme even with very large components and design of a component requires balandng of strength and ductility. Excessive stlffness or brlttleness of the components can induce cracklng at critlcal points of the assemblies such as welds and sharp inside corners. These klnds of features 15 can focus applied stresses to critlcal levels. The components must also be ductile enough to fiex allowing loads to be distrlbuted across ail of the supports for the component.

[0006] In accordance with the présent Invention, a wear component includes a strain relief area that régulâtes and balances stresses in the component caused by the 20 applied loads. The strain relief area Is a portion of the component that has a modified material property such as modulus of elastldty or a modified component property such as stlffness.

[0007] The straln relief may include thlnning of the material, narrowing of the material or a change In material properties in the straln relief area. This results In a decrease In stlffness in the straln relief area in contrast to the balance of the component. The straln relief area flexes and deflects to distribute the stresses across 5 the component support or anchor. Straln relief is effective, for example, between a component support such as a weldment and a loaded area such as the worklng end of wear member or a seat that receives a wear member.

[0008] In one aspect of the Invention, a wear component for earthmovlng equlpment Is provided with a mounting portion, a worklng portion and a straln relief 10 area between the mounting portion and the worklng portion. The mounting portion Is flxed to the equlpment. The worklng portion opérâtes as a seat for a wear member or a wear surface to contact the ground. The straln relief area Is provided between the two portions to permit sufficient flexlbllity to reduce the risk of cracklng or failîng of the flxed attachment on account of the applied loads. This enables greater reliabllity in the 15 wear components and generally a longer usable llfe.

[0009] In one embodiment, the wear component is a base for supportlng a wear member on earthmovlng equlpment such as the lip of an excavating bucket. In this one embodiment, the base wraps around the front edge of the llp and Indudes a mounting portion at each end, i.e., with one mounting end overlying an Inside surface of the lip 20 and one mounting end overlying an outslde surface of the llp. The worklng portion extends between the mounting ends and defines a seat for supportlng a wear member (e.g., a shroud) on the llp. The mounting ends are welded to the llp while the worklng

portion remalns free of weldlng. In this example, the straln relief area Includes a pair of opposite, laterally-open slots, which define a narrow région between the mounting portion and the working portion.

[0010] In another embodiment, the wear component Is a wear member that is welded to the earthmoving equlpment such as a lip of an excavating bucket. In this embodiment, as with the prevlous embodiment, the wear member Includes mounting ends to be fixed to the inside and outslde surfaces of the lip. The working portion is a wearable portion that extends between the mounting ends to contact the earthen materials and, e.g., protect the underlylng lip. The wear member In this example may 10 beashroud.

[0011] The Invention is also applicable to other mining and earthmoving applications such as a base for a runner or a weld-οπ wear member for use on a surface of an excavator bucket, chute, truck body or other equlpment.

[0012] As another alternative embodiment, the entire unwelded portion of the 15 wear component may comprise the strain relief area. In one embodiment, weld portions at opposite ends of the wear component may be welded to a support structure. A mlddle portion (I.e., the working portion) of the wear component not welded to the support structure is free to flex and defiect within the limits of the welded flanges, i.e., without a specifically defined narrow région.

[0013] in one other embodiment of the invention, a base for mounting a wear member to a digging edge of excavating equlpment Includes a seat to receive the wear member, and Inner and outer weld flanges rearward of the seat, each weld flange

welded to one of an Inner surface and an outer surface of the dlgglng edge of the earthmovlng equlpment where the seat and straln reliefs are separate from the dlgglng edge.

[0014] ln another embodiment, a ilp of an excavatlng b ticket having an Interior scoop structure and an exterior surface comprising a main member having an upper surface forming a part of the interior scoop structure of the bucket, a lower surface adapted to form a part of the exterior of the bucket and a front edge face extending across the front of the main member Interconnecting the upper and lower surfaces. The Ilp further Includes a base for mounting a wear member Indudlng a seat that overlles 10 the main member to recelve the wear member, a first welding flange rearward of the seat welded to the upper surface of the lip, and a second welding flange rearward of the seat welded to the lower surface of the Ilp.

[0015] ln another embodiment, a wear assembly comprises a base adapted to be welded to a bucket of an excavatlng machine, wherein the bucket has a dlgglng edge 15 with an Inner face, an outer face and a front edge face. The base Includes a seat bearlng on the front edge face and extending from the front edge face along the inner and outer faces of the digging edge and separate from the dlgglng edge, and at least one a weld flange rearward of the seat secured to the Inner or outer face of the digging edge. A wear member Is received over the base and Includes an aperture generally allgned 20 with a rétention feature on the base. A lock Is received In the aperture to bear against the rétention feature of the base and hold the wear member to the base.

[0016] In another aspect of the Invention, a wear component for earthmoving equlpment is provided with a pair of mountlng portions and a médial working portion. The mountlng portions are deflned at opposite ends of the wear component and are welded to the underlylng support In one example, the underlylngsupport could be a llp of an excavatlng bucket, but It could be other surfaces subjected to earthen materiaîs. In the varlous applications, the worklng portion remalns free of being welded to the underlylng support. This arrangement requlres less weldlng so as to speed removal and attachment, and reduces the rlsk of damaging the underlylng support structure (such as a llp), while still malntalning a se cure attachment of the wear component (whether It be a base or wear member) to the underlylng support.

Brlef Description ofthe Drawlnes [0017] Fig. 1 Is an exploded perspective view of a wear component In the form of a base attached to an underlylng support In the form of an excavator ilp with the base receiving a wear member.

[0018] Fig. 2 Is a perspective view ofthe base of Fig. 1.

[0019] Fig. 3 Isa top view ofthe base.

[0020] Fig. 4 Is a side view of the base.

[0021] Fig. 5 Is a bottom view ofthe base.

[0022] Fig. 6 Is a top view of an alternative configuration of a wear component in the form of a base.

[0023] Fig. 7 Is a bottom view of the base with an alternative configuration.

[0024] Fig. B 1s a top view of the base with another alternative configuration.

[0025] Fig. 9 Is a top view of the base with another alternative configuration.

[0026] Fig. 10 Is a top view of a runner with straln relief areas.

[0027] Fig. 11 is a top view of an alternative configuration of a runner with straln relief areas.

[0028] Fig. 11A Is a slde cross section view of the runner of Fig. 11 with straln relief areas.

[0029] Fig. 12 Is a perspective view of alternative configuration of a base welded to a lip of excavatlng equlpment.

Detalled Description of the Disclosure [0030] Figures 1-5 lllustrate a preferred embodiment ofthe Invention. Figures 6-12 show alternative embodiments.

[0031] Fig. 1 is an exemple of a wear assembly 10 Including a wear member 12 being assembled to a base 20. Base 20 Is flxed to a lip 14 of excavatlng equlpment with an Inside or upper surface 16, an outside or lower surface 18, and a front edge face 14A 15 joinlng the upper and lower surfaces. Base 20 bears on the front edge face and extends rearward along the upper and lower surfaces. Wear member 12 and base 20 are each consldered a wear component of assembly 10.

[0032] Wear member 12 In this Illustrated embodiment Is a shroud. The wear member Includes an opening 12A to receive a rétention system or lock 42 to secure the 20 wear member to the base 20. Wear member 12 has blfurcated legs extending backwards so as to straddle lip 14. The upper leg 12B as shown Is longer and extends farther rearward than the lower leg 12C, but other arrangements are possible.

[0033] Loads applied to wear member 12 during operation are transferred through base 20 to the dlgglng edge or lip ofthe equipment. Substantial loads are applied to the wear assembly during operations generating high stresses in the base and especially at the connection of the base to the lip. These loads are cyclic in nature and hâve In the 5 past tended to generate fatigue fallures in either the base or the weld connecting the base to the lip or in regard to other wear components welded to the lip or other portions of earthmovlng equipment during digging operations. The présent invention reduces this risk of cracking or failure by providing some freedom of movement between the working portion (which in this embodiment Is a seat) and the mounting 10 ends that, in turn, reduces the stress concentrations that can build up and lead to damage and/or loss to the weld or component.

[0034] Base 20 inciudes a working portion or seat 24 at a forward end that wraps around the lip, and a mounting portion or flange 22 at each distal rearward end of base 20. Mounting portion 22 is welded to lip 14, and preferably around the entire outside 15 edge, I.e., along back edge 22A and side edges 22B and 22C, though other arrangements (i.e., with gaps) could be used. The mounting portions could be flxed to the lip by other means such as, e.g., bolting or having the mounting portions cast with the lip or other underlying surface. Base 20 supports wear member 12 with seat 24 being received Into a cavlty 12D of wear member 12 on assembly, though mounting 20 portions can also contact the wear member. in the lllustrated embodiment, pad areas and 25 on base 20 contact wear member 12 during use. The seat could hâve a wlde variety of different constructions to suit the particular wear member to be secured.

Although base 20 Is subject to wear and requires periodlc replacement, It Is covered by wear member 12 during operation resulting In a lower wear rate as compared to wear member 12. As a result, It Is replaced less frequently than wear member 12.

[0035] Base 20 includes an upper welding flange 22 and a lower welding flange 26.

Base 20 deflnes a longitudinal axis LA that extends rearward from the seat between the upper and lower welding flanges 22 and 26. Wear member 12 may be assembled to base 20 along longitudinal axis LA.

[0036] Base 20 includes a weld relief or strain relief area 28 between mounting or welding portion 22 and worklng portion 24, and weld relief or strain relief area 30 10 between mounting or welding portion 26 and worklng portion 24. The strain relief area can be configured in many different ways. in the embodiment of Fig. 2 weld relief or strain relief area 28 lndicated by the dotted line is a throat or narrowed région 29.

Strain relief area 30 connecting welding flange 26 to seating portion 24 Is also a throat

31. A strain relief area adjacent each welding portion 1s preferred, though In certain 15 applications a strain relief area couid be provided between only one welded end 22 and the seat 24.

[0037] Upper weld flange 22 may Indude upper side portions 32 and 34 that extend forward on each side of throat 28. The side portions spaced from the throat portions deflne upper side openings or channels 32A and 34A between the throat and side 20 portions. Lower weid flange 26 may also include lower side portions 36 and 38 extendlng forward on each side of throat 30. The side portions spaced from the throat portion créâtes lower side openings or channels 36A and 38A (hldden here) between

the throat and side portions. The channels are shown with a particular curved shape, but they could hâve a wlde variety of configurations.

[0038] The lower weldlng flange 26 Is preferably welded to bottom surface 18 of lip 14 along back edge 26A, and side edges 268 and 26C. Likewise, In this embodiment, the straln relief area 30 connecting the lower weldlng flange 26 to the seat 24 Is the same configuration as the straln relief area 28 connecting the upper weldlng flange to the seat, though they could be different.

[0039] Upper and lower flanges 22 and 26 serve as the primary supports for base 20. Upper and lower throat areas 29 and 31 are narrower than the seat and adjacent 10 the weld flanges and the seat. The wldth of features such as throat 29 Is defined In a direction transverse to the longitudinal axis LA. in this embodiment, throats 29, 31 hâve a wldth that Is about 80% ofthe maximum wldth of seat 24, but a wide variety of other arrangements with blgger or smaller ratios between the throat and seat wldths are possible.

[0040] The sides and back of the weld flanges are used to weld the flanges to upper and lower faces 16 and 18 of lip 14. One or more weld beads are laid down between the flange edges and the lip surfaces to secure the flanges to the lip. Both upper and lower weld flanges 22 and 26 are secured to lip 14. The balance ofthe surfaces Includingthe throat and seat are free of welds. Seating portion 24 and other features are separate 20 and uncoupled from lip 14 In that they are not attached directly to the lip and can move Independently ofthe lip, though they do bear against the lip during use.

[0041] A more rlgld structure without straln relief areas cannot as effectively dlstribute an applied load with reduced stress build in the part or weld. Where the structure Is too stlff, cracklng tends to occur, primarily at Inside corners, welds and other points that concentrate the stress or hâve experlenced material hardening 5 processes that lower the strength of the matériels. The construction of the présent

Invention with straln relief tends to allevlate excessive stress concentrations and results In a reduced rlsk of cracklng or fallure of the part or weld.

[0042] Loads applied to wear member 12 are primarily transferred to seat 24. Seat

Is constralned through upper and lower throats 29 and 31 which act as straln relief areas 28 and 30 of base 20. Seat 24 under ioad deflects within the constralnts of throats and 31 which flex more than any other portion of base 20 as they are less stlff than seat 24 or flange 22.

[0043] Upper and lower throats 29 and 31 are In tum constralned by the weids along the perlmeter of the flanges at edges 22A, 22B, 22C, 26A, 26B and 26C. This 15 deflectlon of seat 24, and the central location of the throat in relation to the wetded surfaces, allows the applied stresses to better dlsslpate to the entlre weldment a round the flanges.

[0044] Untike the prior art, the flexlng provided by the straln reliefs reduces the rlsk of cracklng base 20 or dlsruptlng the welds that attach base 20 to the llp. This Inventive 20 construction allows the stress relief areas to absorb much of the energy by flexlng and deforming. Finlte Elément Analysis (FEA) comparlsons between bases without a weld relief versus those with a weld or straln relief of the présent disclosure show between a

50% to 90% réduction in peak weld stress with the addition of the présent strain relief areas. Ufecycle results In the lab and In field testlng hâve shown similar improvements to the service life of the components.

[0045] Throat portions of base 20 are deslgned to bend elastlcally. Any plastic deflectlon of a strain relief glvlng a permanent set or deflectlon to base 20 would be beyond the deslgned llmlts of the components. A permanent deflectlon of the strain relief rlsks creatlng cracks In the strain relief and creating stress concentration points that Induce further crack propagation.

[0046] Weld flanges are shown as having a rectangular perlmeter, but other configurations can be used. The perlmeter of the welding flange could be arcuate or could hâve addltlonal protrusions that extend rearward as lllustrated In Fig. 6. Alternative^ or In addition, the welding flange could hâve protrusions extendlng transversely to the slde. Addltlonal protrusions could provide addltlonal support or anchorlng of the base to the ilp.

[0047] Tbe spécifie design of the weld flange and the slde channels may vary widely.

The edges formlng channels 32A, 34A, 36A, 38A may be arcuate as shown In the prevlous examples. In an alternative configuration as shown In Fig. 7 the edges of the channel may Include portions that are parallel to the longitudinal axis LA and some portions that are transverse to the axis. Lower weld flange slde edges 26B and 26C as 20 shown are Inclined to the longitudinal axis.

[0048] In another alternative configuration, the edges of the slde channels may Include portions that are at 45 degrees Inclination to the longitudinal axis as shown In • 13

Fig. 8. In another alternative configuration, upper throat 29 Is narrower than weld flange 22 and seat 24, and weld flange 22 is narrower than seat 24. The shape of feature outllnes of base 20 may vary within a broad range of configurations and, when Intended for a slmllar fu net Ion, still fai! within the scope of the Invention.

. 5 [0049] Referrlng a gain to Fig. 2, base 20 further Inciudes rétention member 40 forward of upper throat 29 on seat 24. In this embodiment, rétention member 40 Inciudes a rearward faclng bearlng surface 41 that generally allgns with opening 12A when wear member 12 Is assembled to base 20. A lock 42 Is assembled In opening 12A and Is received by rétention member 40 to secure wear member 12 on lip 14. Rétention 10 member 40 and opening 12A may be located eisewhere on base 20 and hâve different constructions than what is shown In Fig. 2.

[0050] 8ase 20 may be cast as a single piece with minimal machining required. Due to the size of base 20, the particular metals used In excavating equipment, and certain efficiendes In mold assembly, the resulting cast piece Is subject to dimensional 15 variations. Base 20 may therefore further Include one or more fit pads 44 that may be machined to optimize fit of mating components. Fit pads may be formed on inward surfaces that contact the lip and on outward surfaces of the seat that recelve the cavity ofwear member 12.

[0051] In another embodiment, base 20 may Include only one welding flange. For example, instead of a lower welding flange, the base 20 may Include a lower leg that attaches to the lower surface 18 of lip 14 in a different manner than welding, such as a boit or boss, or Is attached in a more conventional welding arrangement (e.g., without a strain relief area). In yet another embodiment, outer leg 12C of wear member 12 indudes a second rétention feature that engages a corresponding rétention feature on and outer portion of base 20 or outer lip surface 18 to further anchor wear member 12 to llp 14. This example construction may be used to support a wing as a wear member. The various embodiments are usable on many kinds of digglng edges Including, e.g., plate and cast lips, and the forward edges of bucket sldewalls.

[0052] Upper and lower In this application are used to descrlbe the primary embodiment, which Is the attachment of a wear component to a llp. The invention, however, is not so limited. For example, In the example of a wing, the legs would be Inslde and outslde but may not be upper and lower.

[0053] The concepts of the invention are applicable to other applications. Fig. 10 shows a runner or other wear member 120 such as might be attached to a face of earthmovlng equlpment to prevent wear of such equlpment like a bucket, a chute, a truck body, etc. The mlddle portion of the runner Is a working portion 124 defined as a wearable surface, and weld flanges 122 and 126 are at each end of runner 120. This construction could also, altematively, but used in a base for a runner, in which case the working portion is a seat. In a base, the seat would hâve a structure to support the runner and preferably a rétention element to secure the runner in place such as In U.S. Patent Nos. 5,063,695 and 5,241,765, which are Incorporated herein by reference. In runner 120, strain relief areas 128 and 130 separatlng the seat and weld flanges Include slots 132,134, 136, 138 eut transversely Into each side at opposite ends ofthe runner. Holes are eut or drilled at the terminal end of each slot. Weld flanges 122 and 126 at opposlng ends of runner 120 are welded to the support structure such as a bucket surface, while the seat 124 and strain relief areas 128 are separate (i.e., not welded) from the structure. Loads applled at the seat (I.e., by the runner) are regulated by the strain relief so that the stress is dlstrlbuted more evenly across the welds at the outside edge of the weld fl ange.

[0054] Ag. 11 shows a runner 220 slmllar to the runner of Ag. 10. Base 220 includes a seat 224, strain relief areas 22B and 230, and weld flanges 222 and 226 welded to the structure. Here the strain relief is a thlnned portion that modifies the stlffness and increases the flexure ln the area in comparison to the balance of the runner. Fig. 11A is a side cross section view of Fig. 11 showlng the thlnnlng of the runner In the strain relief area 226.

[0055] Stlffness of a component is the inverse of the flexlbllity of the component and both Indlcate the tendency of the component to deflect under an applled force. Stlffness Is an extrlnslc property because It Is dépendent on the shape of the component. A thinner, longer component will be less stîff and more flexible along Its axis than a shorter wlder configuration of the same materlal. A stlffer component will deflect less than a more flexible component of the same materlal under the same applled force.

[0056] The modulus of elastldty Is an Intrinslc property. It's not dépendent on the shape of the component, but on the property of the materlal. Steel has a higher modulus of elastldty than rubber or most plastics. The modulus again Is related to how much a component will bend or deflect under an applled force. A strain relief may

Incorporate modified material composition and/or configuration of the component to provide Increased deflectlon under load compared to other parts ofthe component. [0057] Rather than a thlnnlng of the runner, the modulus of elastlcity In the straln relief area may be modified by a change of material properties In the area. The strain relief area could be heat treated so that the crystal structure Is different In this area. [0058] Altematively, the strain relief can be effected by a different material In this area that modifies the elastlcity. The straln relief area could hâve a more ductile material secured between the seat and the weld flanges. Altematively, the more ductile material could be welded on opposite ends of the seat to form both the straln relief area and the weld flange. The weldlng flange and the straln relief area may be a more ductile material than the seat, but the weldlng flange will hâve a hlgh stlffness due prlmarlly to being fixed and anchored to the underlayment or base. ' [0059] Altematively, the entlre unwelded portion ofthe component may comprise the straln relief area. Fig. 12 shows a base 420 with a seat 424 and weld flanges 422 and 426 welded to upper and lower surface 16 and 18 of llp 14. Here seat 424 of base 420 Is separate and uncoupled from llp 14 and is free to flex and defiect within the llmits of the welded flanges. Seat 424 forward of the welded edges 422A, 422B, 422C fl exe s to fonction as a straln relief area 428. The seat and straln relief In this example overlap. [0060] The method of attachaient has been described as weldlng of the flanges to a surface, but other methods can be used. The base can be bolted to the surface. A worklng portion and a straln relief portion flex and defiect under loads that are transferred through the base to the bolts anchorlng the flanges to the surface.

• 17 [0061] Alternative^, portions of the base, or the entlre base, can be cast with the underlylng surface. The flanges can be cast as part of the underlying surface and the straln relief and working portion wetded to the cast flanges. Aitematlvely, the entire base can be cast as part of the underlylng support surface with the straln relief and the 5 working portion spaced from the underlying surface. This again altows the straln relief and working portion to flex and deflect under loads applied to the working portion without concentratlng stresses that hâve in the past caused cracking in the components.

[0062] While the application has described the Invention primarily In terms of bases 10 for supporting wear members, the Invention could also be employed in wear components that are deflned as a wear member. In these embodiments, the working portion wouid deflne a wearable portion In direct contact with the ground (such as the forward wearable portion of a shroud) rather than a seat for receiving a wear member. Although, shroud is mentioned as an example, the invention could be used In other 15 welded wear members for other edges or broad surfaces on earthmoving equipment.

[0063] It ls believed that the disclosure set forth herein encompasses multiple distinct Inventions with Independent utlllty. While a base for a wear member has been dlsclosed In its preferred form, the spécifie embodiments thereof as disclosed and lllustrated herein are not to be consldered In a llmiting sense as numerous variations 20 are possible. While different configurations hâve been described to achieve a spécifie functionality combinations of these configurations may be used and still fall within the scope of this disclosure. Where the description recites a or a first* element or the • 18 équivalent thereof, such description indudes one or more such éléments, nelther requlrlng nor exduding two or more such éléments. Further, ordinal Indlcators, such as first, second or thlrd, for identified éléments are used to dlstingulsh between the éléments, and do not Indlcate a requlred or limited number of such éléments, and do 5 not Indlcate a particular position or order of such éléments unless otherwise spedfically stated.

Claims (5)

Claîms

1. A wear component for earthmovlng equipment comprising a mou n tin g portion, a worklng portion and a strain relief area between the mountlng portion and the worklng portion, wherein the mountlng portion Is fixed to the earthmovlng

5 equipment, and the strain relief area provides fiexiblllty between the mountlng portion and the worklng portion.

2. The wear component of daim 1 which Includes one said mountlng portion to each slde of the worklng portion, and one said strain relief area between each said mountlng portion and the worklng portion.

10

3. The wear component of daim 2 wherein each said strain relief area

Includes a throat narrowerthan the worklng portion and each said mountlng portion.

4. The wear component of claim 1 wherein each mountlng portion Is orlented rearward of the worklng portion to wrap around a digging edge of the earthmovlng equipment.

15 5. The wear component of daim 1 wherein the worklng portion Is a seat for receiving and supportlng a wear member on the earthmovlng equipment.

6. The wear component of claim 1 wherein the worklng portion 1$ a wearable surface to contact the ground durlng operation of the earthmovlng equipment.

20 7. A base for mountlng a wear member to a digging edge of an excavating bucket Including:

a seat to recelve the wear member;

Inner and outer weld flanges rearward of the seat, each weld flange welded to one of an inner and an outer surface of the dlgglng edge of the excavating bucket;

an inner strain relief separating the seat and the Inner weld flange; and an outer strain relief separating the seat and the outer weld flange.

5 8. The base of claim 7 where the strain reliefs are narrower than the seat and the weid flanges and each strain relief forms a throat.

9. The base of claim 8 where the width of the throat is less than 80% of the wldth of the widest part of the seat.

10. The base of claim 8 where the weld flanges extend forward to each slde

10 of, and spaced from, the throat

11. The base of daim 10 where the weld flanges extending forward to each side of the throat form recesses between the throat and the flange extensions.

12. The base of claim 7 where the strain reliefs flex under loads applied at the seat and distribute the applied loads across the flange welds.

15

13. The base of daim 7 where the upper and lower weld flanges and upper and lower strain reliefs are the same material and the strain relief material Is more ductile than the seat material.

14. The base of daim 7 where strain reliefs are more flexible than the seat and weld flanges.

20 15. The base of claim 7 indudlng a rétention member that receives a lock through an opening of the wear member to secure the wear member to the base.

• »

16. The base of daim 7 where back and side edges of the weld flanges are welded to digging edge surfaces.

17. A base for mountlng a wear member to a surface of earthmovlng equlpment Indudlng:

5 weld flanges at opposite ends of the base, each said weld flange being coupled to the surface with weids; and a seat between the weld flanges, the seat being free of welding to the surface; where loads are applled at the seat during earthmovlng operations and transferred through the flanges to the earthmovlng equlpment.

10 18. The base of daim 17 where the seat deflects in response to the loads applied to the seat.

19. The base of daim 17 Indudlng strain relief separating the seat from each weld flange.

20. The base of claim 19 where the strain reliefs indude slots transverse to 15 an axis between the weld flanges.

21. The base of claim 19 where the stiffness of the strain relief Is less than the stiffness of the seat and the weld flanges.

22. The base of daim 19 where the strain relief comprises a first material and the seat comprises a second material where the first material Is more ductile than

20 the second material.

23. The base of daim 19 where the strain relief Is narrower than the seat forming a throat.

24. A wear assembly comprising:

a base adapted to be welded to a dlgglng edge of an excavatlng bucket, wherein the bucket has an Innerface, an outer face and a front edge face, the base induding:

a seat bearlng on the front edge face and extending from the front edge

5 face along the Inner and outer faces of the dlgglng edge and separate from the dlgglng edge;

a weld flange rearward of the seat secured to the Inner face of the dlgglng edge; and a rétention feature;

10 where the seat Is coupled to the weld flange by a straln relief where the straln relief Is more flexible than the seat and weld flange;

a wear member received over the base and induding an aperture generally allgned with the rétention feature; and a lock received In the aperture to bear against the rétention feature of the base

15 and hold the wear member to the base.

25. A wear assembly In accordance with claim 24 in which the wear member Includes spaced apart legs wherein a first leg includes the aperture and a second leg is shorter than the first leg.

26. A wear assembly In accordance with daim 24 in which the base defines a

20 longitudinal axis and the wear member Is received over the base along the longitudinal axis.

27. A wear assembly In accordance with daim 24 In which the rétention feature of the base Indudes a bearlng surface that Is rearward fadng to contact the lock.

28. A wear assembly In accordance with claim 24 where the straln relief Is a 5 throat portion narrower than the seat.

29. A wear assembly In accordance with daim 24 where the base Includes a second weld flange rearward ofthe seat welded to an outer face ofthe dlggfng edge.

30. A lip of an excavatlng bucket having an Interlor scoop structure and an exterior surface comprising:

10 a main member having:

an upper surface forming a part of the Interlor scoop structure of the bucket;

a Iower surface adapted to form a part ofthe exterior of the bucket; and a front edge face extending across the front of the main member 15 interconnecting the upper and Iower surfaces; and a base for mounting a wear member to the main member induding:

a seat dlssoclated from the llp that overlies the front member to receive the wear member;

a first weld flange rearward of the seat welded to the upper surface of

20 the llp; and a second weld flange rearward of the seat welded to the Iower surface of the lip.

31. A lip In accordance with claim 30 where the base Includes a first straln relief separatlng the first weld flange and the seat, and a second straln relief separatlng the second weld flange and the seat.

32. A lip In accordance with claim 31 where the straln reliefs are narrower 6 than the adjacent weld flange and the seat.

33. A lip In accordance with claim 31 where the straln reliefs are more flexible than the weld flanges and the seat.

34. A lip in accordance with daim 30 where the base Includes a rétention feature that receives a lock through the wear member to secure the wear member to

10 the base.

35. Earthmoving equlpment comprising:

a wearable surface adapted to contact the ground during operation of the earthmoving equlpment, and a wear component se eu red to the wearable surface, the wear component

15 Includinga worklng portion and a welding portion on each oftwo opposite sides ofthe worklng portion, each of the welding portions being welded to the wearable surface, and the worklng portion being free of welding to the wearable surface.

36. The earthmoving equlpment of daim 35 wherein the wearable surface is a dlgging edge with Inner and outer surfaces, and the base wraps around the digging

20 edge with one said welding portion welded to the Inner surface and one other said welding portion welded to the outer surface.

37. The earthmovlng equipment of daim 35 wherein the wearable surface Is a broad surface, and the base overlles the wearable surface with each said weldlng portion welded to the wearable surface.

38. The earthmovlng equipment of daim 35 Including a straln relief area

5 between each said weldlng portion and the worklng portion.