AU2750892A - Abrasion resistant means - Google Patents

Description

ABRASION RESISTANT MEANS.

The following statement is a full description of this invention, including the best method of performing it know to me: This invention relates to abrasion resistant means and to the production thereof, and it refers particularly to a method of and means for extend¬ ing the working life of equipment having wearing surfaces which, in use, are subjected to high abrasion and/or impact forces, such as pulveri-

5. sers, scrapers, crushers, dragline buckets, bucketwheel excavators, chutes, feeders, wear plates, bulldozers, graders, and other mining and earthmoving machinery .

It is known to provide hardened steel studs to be welded to the wearing surfaces of such equipment, such as the studs put out by Sherritt Gordon

10. Mines Limited under its Australian Patent No. 542151, or those put out by Austuds, a Division of Laysand Pty . Ltd. , and known by the trade mark AUSTUDS. It is believed such studs last, in use, somewhat longer than normal hard -facing materials, the time the equipment is out of operation during the installation of the studs is less than with other methods of

15. applying abrasion resistant means, and that such studs are more effect¬ ive than other abrasion resistant means.

This invention has been devised with the object of providing a method of and means for improving the effectiveness of such abrasion resistant means as hitherto known. A further object is to extend the effective

20. life of wear-resistant studs applied to those wearing surfaces, of equi¬ pment as mentioned above, which in use are subjected to abrasion forces. Another object is to provide means for extending the effective life, or increasing the resistance to abrasion, of the wearing surfaces of mining, excavation, earthmoving, and other equipment which, in use, are

25. subjected to high impact loads and/or highly abrasive forces.

A further object is to provide abrasion resistant means which will be relatively easy to apply to the wearing surfaces of articles which, in use, are subjected to highly _^.abrasive forces, as well as being relativ -ely economical in application costs and in the life of such abrasion

30. resistant means.

Yet another object is to provide a method of as well as means for increasing resistance to abrasion, and also to provide resistance to corrosion, wherein such means will not restrict the flow of material passing over it and will not cause bridging in chutes.

35. A still further object is to provide abrasion resistance means for the purposes indicated above which may be designed and/or fabricated to suit the particular and/ or individual requirements of the users of the eguipment, and which will be relatively economical to provide, lighter than wear-plates of the same thickness as hitherto provided, and easy and rapid to install .

The invention devised with these and other objects in view provides the 5. combination with a wearing surface, such as a plate having abrasion and/or impact resistant studs or the like, as hitherto known, of at least one layer of a relatively soft abrasion and/or impact resistant material which covers the studs , or the major part thereof, so as to provide between the studs a pad or pads of abrasion and/or impact 10. resistant material to assist the studs in their pulverising and/ or abrading action whilst reducing the amount of wear of the studs and/or the wearing surfaces or base plate to which the studs are applied. The invention also provides a method of increasing the resistance to abrasive wear, of surfaces which are subjected to abrasion action, 15. which includes the step of applying , to a surface having thereon a number of wear resistant studs, at least one layer of a relatively soft abrasion and/or impact resistant material so as to cover or substant¬ ial ly cover the wear resistant studs .

The relatively soft abrasion and/ or impact resistant material may be 20. a urethane manufactured with abrasion resistant qualities , such as urethane 90 or a urethane known by the trade mark ADIPRENE - for exampl e, ADIPRENE L-100 - or 93 DϋRO "Polyslip" impregnated with wear resistant "Teflon" with increased friction characteristics, or other abrasion resistant plastics material or synthetic rubber or a ceramic 25. material - hereinafter referred to general ly as "relatively soft, abrasion and/or impact resistant material" .

The studs - which do not form part of this invention - may be of stainl ess steel , such as those having a hardness of between 50 and 60 Rockwell C , or mild steel, or case hardened steel , or other material 30. of suitable hardness.

The studs may be fastened to a base plate as by welding - such as by use of an arc welding gun providing a virtual ly smokeless welding operation - and the relatively soft, abrasion and/or impact resistant material is preferably appl ied to the base plate , having the studs 35. thereon, so as to cover the outer ends of the studs and thereby provide a cover over the ends of the studs - as about 2mm to 6mm. However, in some applications of the invention the relatively soft abrasion and/or impact resistant material may extend from the surface of the base plate to within a short distance of the outer extremities of the studs, or 40. it may extend the ful l length of the studs so that the outer ends of the studs are flush with the outer surface of the relatively soft, abrasion and/or impact resistant material . The base plate may be provided, on its rear surface, with one or more bol ts, studs or other fastening means so as to enable it to be fastened to an article which

5. is to be subjected to ear . Alternativel y, the base pl ate may be provided with internally screw- threaded holes to receive bolts for fastening the plate in position , or with other suitable fastening means. The bolts or studs , or screw- threaded holes, may be arranged so that

10. a plate having the rel ativel y soft , abrasion and/or impact resistant material on its outer surface may be rotated to provide for maximum usage of the wear resistant properties . For that purpose the fastening means are arranged in a pattern to enable the pl ate to be removed, turned , and replaced to fit in the same place. Accordingly, the pl ate

15. may be made square in shape , or other even geometri cal shape .

In an al ternative form of the invention the wear-resistant studs and the layer or layers of relatively soft abrasion and/or impact resistant material are applied directly to the work surface, thereby el iminating the need for the baseplates .

20. In a further alternative form of the invention the wear- resist ant studs may be formed integrally with - that is, formed at the same time as - the base plate, as by casting , forging or pressing, and in one aspect of this form of the invention said studs may be formed with heads larger than the stems or shanks .- as somewhat mushroom-shaped.

25. In the use of the baseplate with integral wear-resistant studs, when the relatively soft , abrasion and/ or impact resistant material is applied to the composite plate the stud heads, if l arger than the stems or shanks , wi ll tend to hol d that rel ativel y soft material in pl ace and resist its separation from the baseplate. On the other hand , the

30. basepl ate with integral wear- resistant studs may be used without the rel ativel y sof t, abrasion and/or impact resistant material as a means for reducing the time the equipment is out of operation when replace¬ ment of the said wearing surfaces is required . In order that the invention may be clearl y understood and readily put

35. into practical form I shall now describe a pref erred manner of carrying the invention into ef fect with reference to the accompanying drawings , wherein:

Fig . 1 is a perspective view of a composite pl ate with a number of wear-resistant studs fastened to it, showing a l ayer of

40. rel ativel y soft abrasion and/or impact resistant fl exible plastics material applied to part of the plate;

Fig . 2 is a cross-section on the line and in the direction of the arrows 2 - 2 of Fig. 1; and

Fig. 3 shows an arrangement of several square plates attached to a

5. base surface , as the blade of an earth-moving machine.

The composite plate il lustrated in Figs. 1 and 2 has a baseplate 11 which, as shown in these Figures , is rectangular in shape. That baseplate 11 is of steel of a thickness preferably between 4mm and

40mm, particularly lOirni, and has fastened to its upper surface a

10. suitable number of wear- resistant metal studs 12 .

The number of such studs may vary according to the maximum diameter of said studs, the bond to be achieved between the abrasion and/ or impact resistant f lexibl e plastics material and the baseplate 11, the cost of the product, the strength and/or weight of the composite plate - such

15. as from 10 studs to 138 studs of 16ιtm maximum diameter, and from 10 studs to 100 studs of 20mm maximum diameter, with a plate of 30cm square .

The studs 11 may be applied to the baseplate in even rows , as shown, or in staggered rows, and the composite plates may be square - as

20. depicted in Fig . 3 - or rectangular - as shown in Fig. 1 - or other suitable shape.

The studs 12 may be of stainless steel, such as that having a hardness of between 50 and 60 Rockwel l C, or of case-hardened steel , or mild steel , or other material of suitable hardness .

25. The baseplate 11 has on its under surface screw-threaded bolts or studs

14 by means of which the composite plate may be secured, as by nuts 15, to a work surface 16 provided with holes 17 for the reception of the bolts or studs 14, as shown in Fig. 2.

This invention provides a layer 21 of relatively soft, abrasion and/or

30. impact resistant material - such as Urethane 90 , or 93 DURO "Pol yslip" impregnated with wear resistant "Teflon" with increased f iction characteristics , or any other urethane manufactured with abrasion resistant additions , applied to the baseplate 11 having thereon the wear-resistant studs 12, so as to cover the wear-resistant studs 12

35. with a suitable amount of the relatively soft abrasion and/or impact resistant material - as to a height of 4πtn. This l ayer 21 provides a padding of abrasion resistant material between the studs 12 as well as over the tops of the studs , and it is believed that layer of material

21 assists the studs in their pulverising and/or abrading action whilst

40. reducing the amount of wear of the baseplate 11 and of the studs 12. Al though Fig. l shows the l ayer 21 extending over part only of the basepl ate 11 it is to be understood that in use the l ayer 21 will cover the whole of the upper surf ace of the baseplate.

As an al ternative form of the invention the wear-resistant studs. 12 and

5. the l ayer 21 are applied direct ly to the work surface, thereby eliminating the need for the baseplate 11 , the wear -resistant studs being used in the same range of concentrations as set out above . It is also bel ieved that the wear- resist ant studs may be formed integrall y with the base pl ate - as by casting or by forging - and that

10. the studs may be formed with enlarged heads - somewhat mushroom shaped. When a urethane is used to provide the l ayer 21 the plate 11 having the wear-resistant studs is fi rst sandblasted and then is boxed with light timber ( to provide a reservoi r for the urethane ) and heated to approximatel y 150 degrees centigrade. The urethane is mixed and also

15. heated to approximately 150 degrees centigrade , and is then poured over the wear -resistant studs until said studs are covered by the urethane to a depth of approximatel y 4mm by the liquid urethane. The plate 11, with the urethane layer 21 over the studs 12 , is then baked in an oven for twenty four hours at a temperature of 110 C, removed, and - when

20. cooled sl owl y - it may be applied to a work surface.

The urethane tends to contract at the l ocation of the wear-resistant studs, providing indentations or "dimpl es" 22 .

It is believed that a rubber may be f ound to be suitabl e and used instead of urethane, and then a sheet of the rubber may be applied to

25. the top of the wear -resistant studs (as aff ixed to or incorporated in a base-plate) and the whole assembl y is compressed in moulds to force the rubber to a bonding relationship with the wear-resistant studs and the baseplate. As the probl ems associated with wear resistant products vary as the

30. application of the product is varied it is c lear that the composition of the layer 21 , and the mode of its application , wil l need to be varied so as to suit the purposes for which the work surface is to be used. This invention wi ll be found to be of particular advantage when it is

35. desirable to reduce the effect of clogging of the wear studs, as by the application of the layer 21 to a chute for conveying wet, abrasive, material , or in drag-l ine buckets or other equipment used for excavating hard , dry , rocky material . Accordingly, al though in some usages the appl ication of the layer 21 wil l extend the life of the

40. basepl ate and wear studs by as much as five times , or so I bel ieve, in other usages the layer 21 may not extend the life of the baseplate and wear studs to any comparable extent.

It is believed that in some instances it may be of advantage to apply the relatively soft abrasion and/ or impact resistant material in two

5. or more layers, to make up the total required.

The stud figuration il lustrated in Figs. 1 and 2 may be modified to suit particular arrangements or requirements; it is believed such arrangement wil l prevent the rel atively soft abrasion and/or impact resistant material , particularly urethane, from expanding or warping.

10. It is also believed it wil l assist the studs to absorb shock when the assembly is subjected to impact loading. The cover of the layer 21 of relatively soft abrasion and/or impact resistant material iray wear away relatively quickly , and once the outer ends of the studs become part of the surface they combine with the urethane between them to provide

15. the protection and abrasion resistance required.

The composite arrangement may be fabricated to any thickness and the urethane may be applied by any suitable means and in any suitable manner, as by spraying directly on to the plate 11 or the working surface of a machine to be treated. It wil l be understood that the

20. studs 12 may be of any suitable shape or design, as the shape of the studs is not part of this invention, and the arrangement of those studs may be selected to suit particular requirements.

All such modifications as come within the broad scope of the invention as set out in the appended claims are to be deemed to be included

25. within the ambit of the invention .

Claims (14)

The cl aims defining the invention are as f oll ows :

1. The combination with a wear surface, having a number of wear- resist ant studs , of at l east one layer of a rel ativel y sof t, abrasion and/or impact resistant material which at l east partly covers said studs.

2. The combination as claimed in Claim 1 wherein the wear surf ace is a plate capabl e of being fastened to that part of equipment which in use is subjected to abrasion and/or impact f orces, said pl ate having the wear-resistant studs and the relatively soft, abrasion and/ or impact resistant material on one surface .

3. The combination as cl aimed in Claim 2 wherein the plate has on its other surface a number of studs to permit the pl ate to be attached removably to the equipment with which it is to be used .

4. The combination as cl aimed in any one of the preceding c laims wherein the rel ativel y sof t, abrasion and/ or impact resistant material covers the studs .

5. The combination as claimed in Claim 4 wherein the relatively soft, abrasi on and/or impact resistant material covers the studs initially to a depth of between 2mm and 6ιτm.

6. The combination as claimed in any one of the Claims 1 to 3 inclusive wherein the outer surface of the relatively soft, abrasion and/or impact resistant material is substantial ly flush with the outer ends of the studs .

7. The combination as claimed in any one of the preceding Claims wherein the relatively soft, abrasion and/ or impact resistant material is urethane.

8. The combinati on as cl aimed in any one of the preceding claims wherein the wear surface and the wear- resist ant studs are integral .

9. In the production of a wear resistant surface incorporating a number of wear-resistant studs the step of appl ying to the surf ace at least one layer of a rel ativel y soft , abrasion and/or impact resistant material so as to at least partly cover the wea -resistant studs.

10. In the production of a wear resistant surf ace incorporating a number of wear- resistant studs the step as claimed in Cl aim 9 wherein the rel atively soft , abrasi on and/or impact resistant material is made a thickness to cover the wear-resistant studs .

11. In the production of a wear resistant surface incorporating a number of wear- resist ant studs the step as claimed in Claim 9 or 10 wherein the relatively sof t , abrasi on and /or impact resistant material is made a thickness to cover the wear- resist ant studs by between 2mn and 6ιm

12. In the production of a wear resistant surface the steps of forming as an integral whole a wear plate with a number of wear-resistant studs on one surface and of then applying to the surface of that wear plate having the wear- esist ant studs at least one layer of a relatively soft, abrasion and/ or impact resistant material so as to at least partly cover the wear-resistant studs .

13. A wear surface substantial ly as herein described with reference to and as illustrated in Figs . 1 and 2 or Figs . 2 and 3 of the drawings.

14. The production of a wear resistant surface substantially as herein described with reference to and as illustrated in the drawings.