AU2020213366B1

AU2020213366B1 - Recovery and lifting assembly components

Info

Publication number: AU2020213366B1
Application number: AU2020213366A
Authority: AU
Inventors: Joshua LEPPARD
Original assignee: Soft Rigging Solutions Pty Ltd
Current assignee: Soft Rigging Solutions Pty Ltd
Priority date: 2020-01-17
Filing date: 2020-08-06
Publication date: 2020-12-10
Anticipated expiration: 2040-01-17
Also published as: AU2021236536B1; AU2020200364B1

Abstract

Assemblies of high molecular weight polymer fibres sheathed in braided polymer form each of a coupling or pull ring and a shackle. Each assembly including a first split at a first end to form a first loop and a second split at a second end to form second elongate loop. The coupling or pull ring formed by folding back the second end and the second elongate loop of the assembly to pass under the second elongate loop to pass under a bone secured in the first loop.

Description

RECOVERY AND LIFTING ASSEMBLY COMPONENTS TECHNICAL FIELD

[0001] The present invention relates to equipment for lifting or hauling of heavy loads. More particularly although not exclusively it provides for lifting, hauling and recovery of heavy plant and machinery and, more particularly although not exclusively, to equipment including couplings and shackles for effecting the lifting and hauling.

BACKGROUND

[0002] The lifting, towing and recovery of heavy equipment and plant, particularly in the mining industry, employs, frequently in combination, two components known as a pull ring and a shackle. These two, raising issues of health and safety in their use. The excessive weight of these steel items also leads to their use being awkward and difficult in for example, recovery of heavy machinery bogged or broken down in difficult to access situations where other machines cannot gain access to do the lifting or to rig a steel D shackles in place.

[0003] Another disadvantage of the known pull ring is that it is a rigid ring which can only be positioned about an attachment fixture if there is an accessible end of that fixture.

[0004] Moreover, the repeated use of these steel components chafing against edges, can lead to the formation of sharp burrs, which again are a health and safety hazard. In some situations, steel forms of the pull ring and shackle may fail under extreme conditions and may result in the stored energy within the steel rendering parts airborne and highly dangerous.

[0005] It is known to use a fibre of polymer rope looped around the shank of a rear ripper on a bulldozer for the recovery of disabled plant and equipment, but the sharp leading edge of the shank can damage the rope.

[0006] It is an object of the present invention to address or at least ameliorate some of the above disadvantages.

Notes

[0007] The term "comprising" (and grammatical variations thereof) is used in this specification in the inclusive sense of "having" or "including", and not in the exclusive sense of "consisting only of'.

[0008] The above discussion of the prior art in the Background of the invention, is not an admission that any information discussed therein is citable prior art or part of the common general knowledge of persons skilled in the art in any country.

SUMMARY OF INVENTION

[0008A] In one broad form of the invention there is provided a coupling or pull ring and a shackle; each of the coupling or pull ring and the shackle formed from an assembly of high molecular weight polymer fibres sheathed in braided polymer; wherein the assembly includes a first split at a first end to form a first loop and a second split at a second end to form a second elongate loop; the second end of the assembly and the second elongate loop folded back to pass under the second elongate loop to pass under a bone secured in the first loop and over the first loop to form the coupling or pull ring.

[0008B] In another broad form of the invention there is provided a coupling or pull ring of a coupling and shackle combination; the coupling or pull ring formed from an assembly of spliced together bundles of high molecular weight polymer fibres sheathed in braided polymer material; the assembly being split at a first end to form a first loop; the first loop adapted to receive a transverse bone secured in the first loop by whipping; the assembly being further split at a second end to form a second elongate loop; the second elongate loop folded back to pass under the bone and over the first loop to form the assembly into a ring.

[0008C] In another broad form of the invention there is provided a method of forming a coupling or pull ring of a coupling and shackle combination; the method including the steps of: - forming an assembly of high molecular weight into bundles to form a continuous loop, - controlling shape of the continuous loop by sheathing the continuous loop with braided polymer material, - providing at a first end of the continuous loop a first split to form a first loop adapted to receive a transverse bone, - providing at a second end of the continuous loop a second split to form an elongated second loop, - folding back the second end and the second elongated loop to pass under the bone and over the first loop to form the coupling or pull ring.

[0008D] In another broad form of the invention there is provided a method of recovering a disabled item of equipment by a towing source; the method including the steps of: - attaching one of either a coupling or pull ring or a shackle to a towing fixture of the towing source, - for a coupling or pull ring in open condition, fitting an end with an elongate loop of the coupling or pull ring through a first loop at a first end of a connecting cable, - closing the coupling or pull ring by folding the end with the elongate loop back and around a bone of the pull ring, - attaching one of either a coupling or a shackle to a towing or recovery fixture of the disable item of equipment, - fitting a second loop at a second end of the connecting cable to the coupling or the shackle, - applying sufficient tension to the connecting cable to move the disabled item of equipment and wherein each of the coupling and the shackle includes assemblies of bundles of ultra-high molecular weight polyethylene polymer fibre.

[0008E] In another broad form of the invention there is provided a connecting cable connecting either one of a coupling or a shackle at each outer end of the connecting cable; the connecting cable formed of aramid polymer bundles spliced together and sheathed with an integral loop provided at each outer end; the bundles including a first split at a first end to form a first loop and a second split at a second end to form a second elongate loop; the second end of the assembly and the second elongate loop folded back to pass under the second elongate loop to pass under a bone secured in the first loop and over the first loop to form the coupling or pull ring; each of the coupling and shackle including assemblies of bundles of ultra-high molecular weight polyethylene fibres.

[0008F] In another broad form of the invention there is provided a method of lifting a load; the method including the steps of: - fitting the load with a sling, - with a coupling or pull ring in an open condition feed an end of the coupling or pull ring with an elongate second loop around a lifting point of the sling,

2A

- closing the coupling or pull ring by folding the end with the elongate second loop back on itself to pass the elongate loop under a bone of the coupling or pull ring and over a first loop, - fitting an end of the closed coupling or pull ring over a lifting hook of a lifting device and, wherein the coupling or pull ring is formed of an assembly of bundles of ultra-high molecular weight polyethylene; a first end of the assembly provide with a first loop for securing therein a bone; a second end of the assembly provided with a second elongated slot; the second end adapted for folding back to pass the elongate loop under the bone and over the first loop to close the coupling or pull ring.

[0008G] In another broad form of the invention there is provided an assembly of bundles of fibres of ultra-high molecular weight polyethylene; the bundles forming a coupling or pull ring wherein a first loop is provided at a first end of the assembly for securing therein a bone; an elongate second loop provided at a second end of the assembly; the elongate loop folded back on itself to pass under the bone and over the first loop to form the coupling or pull ring and, wherein the bundles of fibres are chosen in number to define a desired breaking strain of the coupling or pull ring.

[0008H] In another broad form of the invention there is provided a method of constructing the coupling or pull ring and shackle as described above so as to provide a coupling or pull ring and shackle of predetermined maximum breaking strain; said method comprising selecting the diameter of the fibres and selecting the number of laps of fibre forming the bundles so as to effect the predetermined maximum breaking strain.

[00081] In another broad from of the invention there is provided a system of components for use in recovery operations of disabled plant or heavy equipment; the components comprising a coupling or pull ring, a shackle and a coupling guard; the coupling guard preventing damage to sheathing and fibres of a polymer pull ring when the pull ring is looped around a shank of a ripper of a bulldozer; the pull ring formed as an assembly of bundles of fibres of ultra-high molecular weight polyethylene; the bundles provided with a first split at a first end to form a first loop and with a second split at a second end to form a second elongate loop; the second end of the assembly and the second elongate loop folded

2B back to pass under the second elongate loop to pass under a bone secured in the first loop and over the first loop to form the coupling or pull ring.

[0008J] In another broad form of the invention there is provided a method of preventing damage to a rope or polymer pull ring when the rope or pull ring is passed around an element of a recovery vehicle; the method including the steps of: - fitting a coupling guard to the element of the recovery vehicle, - looping the rope or polymer pull ring around the coupling guard, - adjusting the position of the rope or pull ring to lie in a central portion of the coupling guard, and wherein the pull ring is formed as an assembly of bundles offibres of ultra-high molecular weight polyethylene; the bundles provided with a first split at a first end to form a first loop and with a second split at a second end to form a second elongate loop; the second end of the assembly and the second elongate loop folded back to pass under the second elongate loop to pass under a bone secured in the first loop and over the first loop to form the coupling or pull ring.

[0009] In another broad form of the invention there is provided a coupling or pull ring and a shackle; each of the coupling or pull ring and the shackle formed from an assembly of high molecular weight polymer fibres sheathed in braided polymer.

[00010] Preferably, the fibres are arranged in an assembly of multiple bundles spliced together to make one continuous loop.

[00011] Preferably, the coupling or pull ring is formed by firstly providing a split at a first end of the assembly to form a first loop adapted to receive a transverse bone.

[00012] Preferably, the transverse bone is secured in the first loop by whipping.

[00013] Preferably, secondly a second end of the assembly is split to form a second elongate loop.

[00014] Preferably, the second end of the assembly and the second elongate loop are folded back to pass under the bone and over the first loop to form the coupling or pull ring.

2C

[00015] Preferably, the shackle is formed from the continuous loop by a split at each end to form a first loop and a second loop.

[00016] Preferably, an assembly of a bolt and a first thimble is installed in the first loop and a second thimble is installed in the second loop.

[00017] Preferably, an outer end of the bolt is threaded to receive a locking nut; the nut securing the second thimble and second loop to the bolt when the second thimble and second loop are slid over the bolt to form a D shackle.

[00018] According to another broad form of the invention, there is provided a coupling or pull ring of a coupling and shackle combination; the coupling or pull ring formed from an assembly of spliced together bundles of high molecular weight polymer fibres sheathed in braided polymer material.

2D

[00019] Preferably, the assembly is split at a first end to form a first loop; thefirst loop adapted to receive a transverse bone secured in the first loop by whipping.

[00020] Preferably, the assembly is split at a second end to form a second elongate loop; the second elongate loop folded back to pass under the bone and over the first loop to form the assembly into a ring.

[00021] According to another broad form of the invention, there is provided a shackle of a coupling or pull ring and shackle combination; the shackle formed from an assembly of spliced together bundles of high molecular weight polymer fibres sheathed in braided polymer material.

[00022] Preferably, the assembly is split at each end to form respectively a first loop and a second loop.

[00023] Preferably, an assembly of a bolt and a first thimble is installed in the first loop; a second thimble being inserted into the second loop.

[00024] Preferably, a lock nut assembled to a threaded outer end of the bolt secures the second thimble and second loop to the bolt when the second thimble is slid over the bolt to form a D shackle.

[00025] According to another broad form of the invention, there is provided a method of forming a coupling or pull ring of a coupling and shackle combination; the method including the steps of:

forming an assembly of high molecular weight into bundles to form a continuous loop,

controlling shape of the continuous loop by sheathing the continuous loop with braided polymer material,

providing at a first end of the continuous loop a first split to form a first loop adapted to receive a transverse bone,

providing at a second end of the continuous loop a second split to form an elongated second loop,

folding back the second end and the second elongated loop to pass under the bone and over the first loop to form the coupling or pull ring.

[00026] According to another broad form of the invention, there is provided a method of forming a shackle of a coupling or pull ring and shackle combination; the method including the steps of:

providing a split at each end of the continuous loop to form a first loop at a first end and a secondloop atasecondend,

inserting an assembly of a bolt and a thimble into the first loop and inserting a second thimble into the second loop,

sliding the second thimble and second loop over the bolt,

securing the second thimble and second loop on the bolt by a locking nut on a threaded outer end of the bolt to form the shackle.

[00027] According to another broad form of the invention, there is provided a method of recovering a disabled item of equipment by a towing source; the method including the steps of:

attaching one of either a coupling or pull ring or a shackle to a towing fixture of the towing source,

for a coupling or pull ring in open condition, fitting an end with an elongate loop of the coupling or pull ring through a first loop at a first end of a connecting cable,

closing the coupling or pull ring by folding the end with the elongate loop back and around a bone of the pull ring,

attaching one of either a coupling or a shackle to a towing or recovery fixture of the disable item of equipment,

fitting a second loop at a second end of the connecting cable to the coupling or the shackle,

applying sufficient tension to the connecting cable to move the disabled item of equipment and wherein each of the coupling and the shackle includes assemblies of bundles of ultra-high molecular weight polyethylene polymer fibre.

[00028] Preferably, the coupling or pull ring includes a first loop formed at a first end of the assembly of polymer fibres; a bone inserted into the first loop secured in position by whipping.

[00029] Preferably, the elongate loop is formed at a second end of the assembly of polymer fibres.

[00030] Preferably, a length of the assembly of bundles of polymer fibres of the shackle is provided at each end with a loop.

[00031] Preferably, an assembly of a steel thimble and a steel bolt is inserted into a first of the loops; a steel thimble being inserted into a second of the loops.

[00032] Preferably, in a closed condition the thimble in the second of the loops is slid over an outer end of the bolt and a securing nut is fitted to a threaded end of the bolt.

[00033] According to another broad form of the invention, there is provided a connecting cable connecting either one of a coupling or a shackle at each outer end of the connecting cable; the connecting cable formed of aramid polymer bundles spliced together and sheathed with an integral loop provided at each outer end; each of the coupling and shackle including assemblies of bundles of ultra-high molecular weight polyethylene fibres.

[00034] According to another broad form of the invention, there is provided a method of lifting a load; the method including the steps of:

fitting the load with a sling,

with a coupling or pull ring in an open condition feed an end of the coupling or pull ring with an elongate second loop around a lifting point of the sling,

closing the coupling or pull ring by folding the end with the elongate second loop back on itself to pass the elongate loop under a bone of the coupling or pull ring and over a first loop,

fitting an end of the closed coupling or pull ring over a lifting hook of a lifting device and,

wherein the coupling or pull ring is formed of an assembly of bundles of ultra-high molecular weight polyethylene; a first end of the assembly provide with a first loop for securing therein a bone; a second end of the assembly provided with a second elongated slot; the second end adapted for folding back to pass the elongate loop under the bone and over the first loop to close the coupling or pull ring.

[00035] According to another broad form of the invention, there is provided an assembly of bundles of fibres of ultra-high molecular weight polyethylene; the bundles forming a coupling or pull ring wherein a first loop is provided at afirst end of the assembly for securing therein a bone; an elongate second loop provided at a second end of the assembly; the elongate loop folded back on itself to pass under the bone and over the first loop to form the coupling or pull ring and, wherein the bundles of fibres are chosen in number to define a desired breaking strain of the coupling or pull ring.

[00036] According to another broad form of the invention, there is provided an assembly of bundles of fibres of ultra-high molecular weight polyethylene forming a shackle; the assembly provided at each outer end with respectively a first loop and a second loop; an assembly of a metal bolt and a first metal thimble inserted into the first loop and a second metal thimble inserted into the second loop to form the shackle when the second loop is slid over the bolt and a locking nut is fitted to a threaded end of the bolt and, wherein the bundles offibres are chosen in number to define a desired breaking strain of the shackle.

[00037] Preferably, the method of constructing the coupling or pull ring and shackle as described above so as to provide a coupling or pull ring and shackle of predetermined maximum breaking strain; said method comprising selecting the diameter of the fibres and selecting the number of laps of fibre forming the bundles so as to effect the predetermined maximum breaking strain.

[00038] According to another broad form of the invention, there is provided a system of components for use in recovery operations of disabled plant or heavy equipment; the components comprising a coupling or pull ring, a shackle and a coupling guard; the coupling guard preventing damage to sheathing and fibres of a polymer pull ring when the pull ring is looped around a shank of a ripper of a bulldozer.

[00039] Preferably, the coupling or pull ring is formed from an assembly of high molecular weight polymer fibres sheathed in braided polymer, the fibres arranged into an assembly of multiple bundles spliced together to make one continuous loop.

[00040] Preferably, the coupling guard is formed of high molecular weight polymer material; the coupling guard generally formed as a half cylinder with a central channel formed in a planar face of the half cylinder and extending the length of the half cylinder.

[00041] Preferably, a central portion of the length of the half cylinder extending between flanking portions is of a smaller radius than that of each of the flanking portions at outer ends of the half cylinder.

[00042] Preferably, the central channel is sized to be a sliding fit around a leading edge of the shank of a ripper of a bulldozer or a rear bar of other earth moving plant.

[00043] Preferably, the system as described in use the coupling guard is fitted to the leading edge of the shank of the ripper and pull ring positioned around the central portion of smaller radius of the shank guard.

[00044] According to another broad form of the invention, there is provided a method of preventing damage to a rope or polymer pull ring when the rope or pull ring is passed around an element of a recovery vehicle; the method including the steps of:

fitting a coupling guard to the element of the recovery vehicle,

looping the rope or polymer pull ring around the coupling guard,

adjusting the position of the rope or pull ring to lie in a central portion of the coupling guard.

[00045] Preferably, the guard is a coupling guard for fitting to a leading edge of a shank of a ripper of a bulldozer.

[00046] According to another broad form of the invention, there is provided a coupling guard for preventing damage to a rope or polymer pull ring looped around a shank of a ripper of a bulldozer in a plant or heavy equipment recovery and towing operation; the coupling guard including a rounded surface and a channel sized to fit around a leading edge of the shank of the ripper.

[00047] Preferably, the coupling guard is generally in the form of a half cylinder with a central portion of smaller radius between flanking portions at outer ends of the half cylinder.

[00048] Preferably, a channel extends the length of the half cylinder; the channel formed central in a planar face of the half cylinder.

[00049] Preferably, use of the pull ring wherein the pull ring is looped around an element of a recovery vehicle; the pull ring protected from sharp edges of the element by locating the pull ring around a guard applied to the element.

[00050] Preferably, the use of the pull ring wherein the guard is adapted to fit to a leading edge of a ripper of bulldozer.

BRIEF DESCRIPTION OF DRAWINGS

[00051] Embodiments of the present invention will now be described with reference to the accompanying drawings wherein:

[00052] Figure 1 is a first view of an assembly of polymer fibre bundles sheathed in a polymer webbing prior to assembly into a first component of the invention;

[00053] Figure 2 is a second view of the assembly offigure 1;

[00054] Figure 3 is a top view of the assembly offigures 1 and 2 assembled into the first component of the invention;

[00055] Figure 4 is a view from below of the assembled first component offigure 3;

[00056] Figure 5 is a side view of the assembled component of figures 3 and 4;

[00057] Figure 6 is an end view of the assembled component of figures 3, 4 and 5;

[00058] Figure 7 is a sectioned view of the component of figures 3 to 6 showing a typical arrangement of the bundles of polymer fibres within the polymer webbing;

[00059] Figure 8 is a view of an assembly of polymerfibre bundles sheathed in polymer webbing prior to assembly into a second component of the invention;

[00060] Figure 9 is a top view of the assembly offigure 8 assembled to form the second component shown in an open condition;

[00061] Figure 10 is a top view of the assembled component of figure 9 shown in a closed condition;

[00062] Figure 11 is a side view of the assembled component of figure 10;

[00063] Figure 12 is an end view of the assembled component offigure 10;

[00064] Figure 13 is a sectioned end view of the assembled component of figure 10,

[00065] Figure 14 is a view of a recovery operation with the components of the invention in use,

[00066] Figure 15 is a view of the coupling of the invention in use in a lifting operation.

[00067] Figure 16 is a view from above of a coupling guard according to a preferred embodiment of this component,

[00068] Figure 16A is a perspective view of the coupling guard of figure 16,

[00069] Figure 17 is a side view of the coupling guard of figure 16,

[00070] Figure 18 is a sectioned side view of the coupling guard of figures 16 and 17,

[00071] Figure 19 is a view of a typical plant recovery operation with the coupling guard of figures 16 to 18 in use,

[00072] Figure 20 is a view of another example of a recovery operation with the coupling guard of figures 16 to 18 in use.

DESCRIPTION OF EMBODIMENTS

[00073] The present invention provides alternatives to three components; a soft coupling, a shackle or, more specifically, a "D-shackle" and connecting cable. These two components may be used in combination to attach cables/slings or strops to attachment points or structural features of, for example mining equipment and plant or cranes, in cases where such equipment or plant must be lifted, recovered or moved. Furthermore, the invention provides for a fourth component, a coupling guard for use with the soft coupling, shackle and connecting cable.

The Coupling

[00074] With reference to figures 1 and 2, the first component of the invention is formed from an assembly 10 of multiple laps or bundles 11 (see figure 7), ranging from 4 to 14 for example, of endless Dyneema, PBO or another type of ultra-high molecular weight polyethylene (UHMWPE) fibre, spliced together to make one continuous loop 12.

[00075] A braiding 14 of the same polyethylene or similar material is used to sheathe the bundles to control and give them the shape shown in figures 1 and 2. One end 16 of the assembly 10 is split to form a first loop 18 adapted to receive a metal transverse "bone" or peg 20 (as shown in figure 3) which is whipped into the first loop 18 with suitable cord (not shown).

[00076] The other end 22 of the assembly 10 is similarly split to form a second, elongate loop 24, thus forming two loops interconnected by a central section of bundles. It will be noted from the cross-section view of figure 7, that the central section interconnecting the two loops 18 and 24 comprises of double the number of bundles than the bundles forming the loops.

[00077] With the bone 20 secured within the first loop 18, the other end of the assembly and second elongate loop 24 is folded back on itself to form the arrangement shown in figures 3 to 6 in which the elongate loop 24 passes under the bone 20 and around the first loop 18. Thus, as best shown in figure 5, the assembled first component of the invention forms a "soft" coupling 26.

[00078] It will be understood that the arrangement of the bone 20 permanently located in the first loop 18, allows for the soft coupling 26 to be opened so as to allow it to be passed around some fixture of a recovery vehicle, such as for example the blade of a bulldozer ripper where, as shown in figure 19, the ripper tip is on or partly buried in the ground, or around a rear bar of other earth moving plant such as shown in figure 20.

The Shackle

[00079] Turning now to figures 8 to 13, the second component of the invention is formed similarly from an assembly 30 of bundles of UHMWPE or similar polymer material and sheathed with braiding 32 to take the form of that shown in figure 8. As before for the first component above, the bundles are split to form a first loop 34 at first end 36 and a second loop 38 at the second end 40.

[00080] As shown in figure 9, an assembly of a metal bolt 42 and a first metal thimble 44 is installed in first loop 34, with a second steel thimble 46 inserted into the second loop 38. The outer end of the bolt 42 is threaded so that as shown in figure 10, when the assembly of bundles 30 is folded over and the second thimble 46 is slid over the bolt, a securing nut 48 locks the assembly of the second component into the well-known form of a D shackle 49.

[00081] In an alternative arrangement of the second component, the thimbles are sized and the bolt lengthened to accommodate two sets of the assembly 30, so doubling the capacity of the shackle.

Connecting Cable

[00082] A third component of the invention comprises a connecting cable 50 (shown in use in figure 14), preferable formed of an aramid, such as Technora by the Teijin Aramid a high strength polymer closely related to Kevlar. Similar to the construction of the described above, the cable is formed of multiple bundles of this material spliced together and sheathed and spliced at each outer end to form a first and second integral loop 52 and 54.

[00083] All three components may be sized to conform to a range of load bearing specifications as shown for example in the table below, in which WLL refers to Working Load Limit and MBS to Minimum Breaking Strength:

• 17ton WLL, 102ton MBS

• 25ton WLL, 150ton MBS

• 55ton WLL, 330ton MBS

• 65ton WLL, 390ton MBS

• 75ton WLL, 450ton MBS

• 85ton WLL, 51Oton MBS

• 95tob WLL, 570ton MBS

• 110ton WLL, 660ton MBS

• 125ton WLL, 750ton MBS

The Coupling Guard

A coupling guard 100 is formed of a high molecular weight polymer, preferably, Nylon 6XAU, highly resistant to compression. Tests have shown it to minimally deform under loads of over 100tons. As shown in figure 16, the coupling guard 100 includes a rounded surface 102 preferably is in the form of a half cylinder with a central channel 104 formed in the planar face 106 and extending the length of the half cylinder. A central portion 108 is of a smaller radius then that of two flanking portions 110 and 112 at each outer end. The channel 102 is sized to be a close sliding fit around the leading edge 114 of, in this example, the coupling 116 of the ripper 118 of a bulldozer 120 as shown in figure 19.

[00084] In a preferred configuration, the radius of the half cylinder is 125mm, with that of the central portion 104 115mm and the overall length of the coupling guard 245mm. The coupling guard 100 may be provided in a number of sizes, both of the overall dimensions and, more particularly those of the channel 104 to suit the rippers of different bulldozers.

[00085] As shown in Figure 20, a coupling guard 200 is used to protect the soft coupling 224 from the relatively sharp edges of a rear horizontal bar 216 of an earth moving machine 226 such as a grader. Such bars are typically formed of heavy channel section so that the edges of the flanges of the channel section would tend to cut into and damage the soft coupling. In this example the channel 104 (see figure 16) of the coupling guard 200 is sized to suit the channel section rear bar. The soft coupling is then looped around the guard.

[00086] In a further preferred embodiment, the coupling guard 100 may be provided with a securing strap 228 as shown in figure 19 for securing the guard in place while the coupling is positioned around the bulldozer blade or other structure of a recovery or towing vehicle.

Other Embodiments

[00087] In an alternative arrangement, the assembly of the continuous loop of material may be provided with a single split to provide one loop, so forming a coupling.

[00088] In a further embodiment, of both the coupling and the shackle, the number of laps or bundles of fibre forming the assembly may be selected for a desired breaking strain. This may be desirable where, for example, an excessive pulling force in a recovery operation could damage equipment.

[00089] By way of particular example, it has been determined that for laps of fibre where the fibre is 10mm diameter Dyneema results in a breaking strain of approximately 160 tonnes.

[00090] The methodology of selecting the fibres and mode of construction of the coupling provides the ability to offer couplings of specified breaking strain which is desirable in certain circumstances.

In Use

[00091] The above components may be used in a similar manner in which the steel pull ring and shackles are currently used. In a system for recovering a disabled item of equipment by a towing source, a typical situation is one in which a large, broken down dump truck 56 is to be recovered by a bulldozer 58. The system, illustrated in figure 14 then includes the step of fitting a pull ring 10 (or a shackle) to a towing fixture 60 on the bulldozer. In the example of figure 14, a pull ring 10 while opened, is fitted to the towing fixture 60 of a towing source, in this example the bulldozer 58 and retained in the fixture 60 by pin 62. (Alternatively, coupling 10 could be passed around a ripper shank of the bulldozer as shown in figure 19 and the pull ring 10 passed around the coupling guard 100).

[00092] One of the loops 52 of the connecting cable 50 is then threaded onto the elongated loop 24 end of the pull ring and that loop folded back and around the bone 20 to close the pull ring.

[00093] Referring again to figure 14, the loop 54 at the other end of the connecting cable/strop or sling 50 may be attached to a shackle 49, which in turn can be fitted to a towing or recovery fixture of the dump truck 56 of this example. It will be understood that either a coupling or a shackle may be used at each end of the cable 50. Sufficient tension then applied to the connecting cable by the towing force is then applied to recover the disabled item.

[00094] The same combination of components of the invention, may be use in load lifting applications. Thus, by way of example as shown in figure 15, an end of the pull ring (or a shackle) of the invention while open may be passed around straps 70 of a sling fitted around a load 72. With the pull ring closed as described above, the other end of the pull ring can then be passed over the hook 74 of a lifting device such as a crane (not shown) to lift and transfer the load to a required location.

[00095] The components of the invention provide a light-weight, soft substitute for the heavy and cumbersome steel pull ring, D shackle cable equipment generally in use in the industry. Being much lighter, a combined weight of 9kgs replacing that of 110Kg of the pull ring and shackle for example, allows almost anyone to safely handle the ring and shackle. The polymer composition of the components further makes them highly suitable for underground coal mining operations.

Claims

CLAIMS 1. A coupling or pull ring and a shackle; each of the coupling or pull ring and the shackle formed from an assembly of high molecular weight polymer fibres sheathed in braided polymer; wherein the assembly includes a first split at a first end to form a first loop and a second split at a second end to form a second elongate loop; the second end of the assembly and the second elongate loop folded back to pass under the second elongate loop to pass under a bone secured in the first loop and over the first loop to form the coupling or pull ring .
2. The coupling or pull ring and shackle of claim 1 wherein the fibres are arranged in an assembly of multiple bundles spliced together to make one continuous loop.
3. The coupling or pull ring and shackle of claim 1 or 2 wherein the transverse bone is secured in the first loop by whipping.
4. A coupling or pull ring of a coupling and shackle combination; the coupling or pull ring formed from an assembly of spliced together bundles of high molecular weight polymer fibres sheathed in braided polymer material; the assembly being split at a first end to form a first loop; the first loop adapted to receive a transverse bone secured in the first loop by whipping; the assembly being further split at a second end to form a second elongate loop; the second elongate loop folded back to pass under the bone and over the first loop to form the assembly into a ring.
5. The coupling or pull ring and shackle combination of claim 4, wherein the spliced together bundles of high molecular weight polymer fibres are sheathed in braided polymer material.
6. A method of forming a coupling or pull ring of a coupling and shackle combination; the method including the steps of:

- forming an assembly of high molecular weight into bundles to form a continuous loop, - controlling shape of the continuous loop by sheathing the continuous loop with braided polymer material, - providing at a first end of the continuous loop a first split to form a first loop adapted to receive a transverse bone, - providing at a second end of the continuous loop a second split to form an elongated second loop, - folding back the second end and the second elongated loop to pass under the bone and over the first loop to form the coupling or pull ring.
7. A method of recovering a disabled item of equipment by a towing source; the method including the steps of: - attaching one of either a coupling or pull ring or a shackle to a towing fixture of the towing source, - for a coupling or pull ring in open condition, fitting an end with an elongate loop of the coupling or pull ring through a first loop at a first end of a connecting cable, - closing the coupling or pull ring by folding the end with the elongate loop back and around a bone of the pull ring, - attaching one of either a coupling or a shackle to a towing or recovery fixture of the disable item of equipment, - fitting a second loop at a second end of the connecting cable to the coupling or the shackle, - applying sufficient tension to the connecting cable to move the disabled

item of equipment and

wherein each of the coupling and the shackle includes assemblies of bundles of ultra-high molecular weight polyethylene polymer fibre.
8. The method of claim 7 wherein the coupling or pull ring includes a first loop formed at a first end of the assembly of polymer fibres; a bone inserted into the first loop secured in position by whipping.
9. The method of claim 7 or 8 wherein the elongate loop is formed at a second end of the assembly of polymer fibres.
10. The method of claims 7 to 9 wherein a length of the assembly of bundles of polymer fibres of the shackle is provided at each end with a loop.
11. A connecting cable connecting either one of a coupling or a shackle at each outer end of the connecting cable; the connecting cable formed of aramid polymer bundles spliced together and sheathed with an integral loop provided at each outer end; the bundles including a first split at a first end to form a first loop and a second split at a second end to form a second elongate loop; the second end of the assembly and the second elongate loop folded back to pass under the second elongate loop to pass under a bone secured in the first loop and over the first loop to form the coupling or pull ring; each of the coupling and shackle including assemblies of bundles of ultra-high molecular weight polyethylene fibres.
12. A method of lifting a load; the method including the steps of:

- fitting the load with a sling, - with a coupling or pull ring in an open condition feed an end of the coupling or pull ring with an elongate second loop around a lifting point of the sling, - closing the coupling or pull ring by folding the end with the elongate second loop back on itself to pass the elongate loop under a bone of the coupling or pull ring and over a first loop, - fitting an end of the closed coupling or pull ring over a lifting hook of a lifting device and,

wherein the coupling or pull ring is formed of an assembly of bundles of ultra high molecular weight polyethylene; a first end of the assembly provide with a first loop for securing therein a bone; a second end of the assembly provided with a second elongated slot; the second end adapted for folding back to pass the elongate loop under the bone and over the first loop to close the coupling or pull ring.
13. An assembly of bundles of fibres of ultra-high molecular weight polyethylene; the bundles forming a coupling or pull ring wherein a first loop is provided at a first end of the assembly for securing therein a bone; an elongate second loop provided at a second end of the assembly; the elongate loop folded back on itself to pass under the bone and over the first loop to form the coupling or pull ring and, wherein the bundles of fibres are chosen in number to define a desired breaking strain of the coupling or pull ring.
14. A method of constructing the coupling or pull ring and shackle of any one of claims 1 to 6 so as to provide a coupling or pull ring and shackle of predetermined maximum breaking strain; said method comprising selecting the diameter of the fibres and selecting the number of laps of fibre forming the bundles so as to effect the predetermined maximum breaking strain.
15. A system of components for use in recovery operations of disabled plant or heavy equipment; the components comprising a coupling or pull ring, a shackle and a coupling guard; the coupling guard preventing damage to sheathing and fibres of a polymer pull ring when the pull ring is looped around a shank of a ripper of a bulldozer; the pull ring formed as an assembly of bundles of fibres of ultra-high molecular weight polyethylene; the bundles provided with a first split at a first end to form a first loop and with a second split at a second end to form a second elongate loop; the second end of the assembly and the second elongate loop folded back to pass under the second elongate loop to pass under a bone secured in the first loop and over the first loop to form the coupling or pull ring.
16. The system of claim 15 wherein the bundles offibres are sheathed in braided polymer, the fibres arranged into an assembly of multiple bundles spliced together to make one continuous loop.
17. The system of clam 15 wherein the coupling guard is formed of high molecular weight polymer material; the coupling guard generally formed as a half cylinder with a central channel formed in a planar face of the half cylinder and extending the length of the half cylinder.
18. The system of claim 17 wherein a central portion of the length of the half cylinder extending between flanking portions is of a smaller radius than that of each of the flanking portions at outer ends of the half cylinder.
19. The system of claim 17 or 18 wherein the central channel is sized to be a sliding fit around a leading edge of the shank of a ripper of a bulldozer or a rear bar of other earth moving plant.
20. The system of any one of claims 17 to 19 wherein in use the coupling guard is fitted to the leading edge of the shank of the ripper and pull ring positioned around the central portion of smaller radius of the shank guard.
21. A method of preventing damage to a rope or polymer pull ring when the rope or pull ring is passed around an element of a recovery vehicle; the method including the steps of:

- fitting a coupling guard to the element of the recovery vehicle, - looping the rope or polymer pull ring around the coupling guard, - adjusting the position of the rope or pull ring to lie in a central portion of

the coupling guard, and wherein the pull ring is formed as an assembly of bundles offibres of ultra-high molecular weight polyethylene; the bundles provided with a first split at a first end to form a first loop and with a second split at a second end to form a second elongate loop; the second end of the assembly and the second elongate loop folded back to pass under the second elongate loop to pass under a bone secured in the first loop and over the first loop to form the coupling or pull ring.
22. The method of claim 21 wherein the guard is a coupling guard for fitting to a leading edge of a shank of a ripper of a bulldozer.
23. The method of claim 21 wherein the coupling guard is generally in the form of a half cylinder with a central portion of smaller radius between flanking portions at outer ends of the half cylinder.
24. The coupling guard of claim 23 wherein a channel extends the length of the half cylinder; the channel formed central in a planar face of the half cylinder.
25. Use of the pull ring of any one of claims 1 to 6 wherein the pull ring is looped around an element of a recovery vehicle; the pull ring protected from sharp edges of the element by locating the pull ring around a guard applied to the element.
26. The use of the pull ring of claim 25 wherein the guard is adapted to fit to a leading edge of a ripper of bulldozer.