WO2021081592A1 - A method and apparatus for drilling and positioning a collar support sleeve into a blast hole - Google Patents

Abstract

The invention provides an apparatus and method for preventing surrounding loose rock fragments from falling or collapsing into a bore hole during drilling and immediately after removal of a drill string from the bore hole. The apparatus includes bore hole sleeve for a bore hole drill, the sleeve including a tube member adapted to be coupled to a mast of a mobile bore hole drill and to be positioned within the collar region of a bore hole, the tube member including a longitudinal internal passage for receiving a drill string therethrough and an external surface for facing outwardly against a wall of the bore hole.

Description

A METHOD AND APPARATUS FOR DRILLING AND POSITIONING A COLLAR SUPPORT SLEEVE INTO A BLAST HOLE

TECHNICAL FIELD

[001] The present invention relates to the field of bore hole drilling, particularly although not exclusively in blasting operations for mining and quarrying.

BACKGROUND

[002] Above ground, open cut mining methods can involve blasting with explosives to dislodge bulk quantities of ore for excavation and recovery. Bench blasting is a process that involves drilling holes into rock to depths of up to 50 metres or more and filing the holes with explosive material to form a column charge that fractures the rock in a controlled manner. The blasting holes can have diameters as large as 270 to 311 or even up to 350 millimetres.

[003] Blast holes are typically drilled using percussive drilling techniques. Percussion energy is generated by a reciprocating piston wherein each piston impact causes tungsten carbide buttons in the drill bit penetrate the rock. The drill string is rotated after each impact to turn the drill bit to a new position so that the buttons strike fresh rock surfaces. Top hammer percussive drilling is where percussion energy is applied by a piston to an upper end of the drill string. Down-the-hole percussive (DTH) drilling is where percussive energy is applied by a piston to a lower portion of the drill string, just above the bit. Top hammer drilling is generally used for drilling relatively smaller diameter holes whereas DTH drilling is generally used for drilling larger diameter holes.

[004] Rotary drilling is another technique for drilling blast holes. Rotary drilling does not use percussion. Instead, rotary drilling applies a feed force and a rotation torque. The torque causes the bit to rotate, while the feed force holds the bit firmly against the rock surface. The combination of rotary torque and feed force enables the bit to penetrate the rock by cutting into the rock surface. [005] Most of the rock that is fractured after a blasting operation is removed by excavators for further processing. However, significant quantities of loose rock fragments, or “preconditioned” material, from the sub-drilled region after achieving the Reduced Level (RL) can remain on the bench in the location where blast holes for a subsequent blasting operation are drilled. A preconditioned layer depth of up to 4 metres or more can improve the efficiency of the comminution process by maximising the volume of fine fragmentation that results from the subsequent blasting operation.

[006] Loose rock fragments from the preconditioned layer surrounding the blast hole, commonly referred to as the “collar” region of the blast hole, can collapse into the blast hole after drilling. Applicant’s patent application W02019014716 discloses a collar support apparatus for preventing surrounding loose rock fragments from falling or collapsing into a blast hole. The apparatus includes a normally flat flexible sheet that is formed into a curved form to define a longitudinal passage and is then inserted into the open end of a blast hole. The curved sheet closely faces an internal surface of the blast hole and forms a barrier preventing surrounding loose rock fragments from falling or collapsing into the open end of the blast hole.

[007] However, even during drilling or immediately after drilling, and before the collar support apparatus can be located in position, surrounding loose rock fragments can collapse into the bore hole. Accordingly, there exists a need for a drilling system that minimises any chance for loose rock fragments from the preconditioned layer to collapse into the bore hole.

[008] Also the process of manually manipulating a preformed collar support apparatus and inserting the collar support apparatus into the bore hole can be laborious and time consuming. Accordingly, there exists a need for a drilling system whereby a collar support apparatus can be positioned within a bore hole that is less laborious and time consuming.

[009] Any discussion of background art throughout the specification should in no way be considered as an admission that any of the documents or other material referred to was published, known or forms part of the common general knowledge.

SUMMARY OF THE INVENTION

[0010] Accordingly, in one aspect, the invention provides a bore hole sleeve apparatus for a bore hole drill, the sleeve apparatus including a tube member adapted to be coupled to a mast of a mobile bore hole drill and to be positioned within the collar region of a bore hole, the tube member including a longitudinal internal passage for receiving a drill string therethrough and an external surface for facing outwardly against a wall of the bore hole.

[0011] Preferably, the tube member and the mast include a coupling for securing the tube member to the mast.

[0012] Preferably, the coupling is adapted for releasably securing the tube member to the mast.

[0013] Preferably, the coupling is adapted for permitting movement of the tube member relative to the mast between a position in which the tube member is aligned with an axis of the drill string and another position in which the tube member is offset from the axis of the drill string while the tube member and the mast remain coupled together.

[0014] Preferably, the coupling includes a slot mount coupling.

[0015] Preferably, the coupling includes an adapter secured to the mast that includes a slot for receiving a flange at an end of the tube member.

[0016] Preferably, the slot is defined between a pair of opposing plates that, in use, are oriented substantially parallel with the bench surface.

[0017] Preferably, the flange is adapted to enter and exit the slot with horizontal movement of the adapter relative to the tube member. [0018] Preferably, the flange is adapted to move within the slot between a position in which the tube member is aligned with an axis of the drill string and another position in which the tube member is offset from the axis of the drill string.

[0019] Preferably, the flange is a substantially planar member fixed at the end of the tube member. Preferably, the flange has a polygonal shape. Preferably the flange has opposite tapering edges providing a narrower width at one end of the flange for guiding the flange into the slot.

[0020] Preferably, the pair of plates each include an opening, preferably located centrally, for receiving the drill string therethrough and for alignment with the longitudinal internal passage of the tube member.

[0021] Preferably, the opening through a lower one of the plates is open to one side of the plate for receiving the tube member therewithin.

[0022] Preferably, one or more protrusions extend from the flange for engaging the bench surface and for maintaining a gap between the flange and the bench surface. Preferably, the protrusions extending from the flange are adapted for engaging the bench surface and for supporting the mast thereon. Preferably, the protrusions are adapted to maintain the flange proud of the bench surface to allow one of the plates of the adapter to locate between the flange and the bench surface.

[0023] Preferably, the tube member is adapted to be self-supporting within the collar of the bore hole for receiving a collar support apparatus within the longitudinal internal passage.

[0024] Preferably, the tube member includes a rigid, cylindri cally shaped body portion with openings at opposite ends and the longitudinal internal passage extending therebetween. [0025] In a preferred embodiment, the tube member is self-supporting with an end of the longitudinal internal passage at the level of the bench surface.

[0026] In another aspect, the invention provides a drilling apparatus, including a mobile platform, a mast disposed on the platform including a support for a drill string; a drill string rotation and driving mechanism for driving the drill string to bore a hole into rock; a bore hole sleeve apparatus including a tube member coupled to the mast for positioning within the collar region of a bore hole, the tube member including a longitudinal internal passage for receiving the drill string therethrough and an external surface for facing outwardly against a wall of the bore hole.

[0027] In embodiments, the tube member is movable while remaining coupled to the mast between a position in which the tube member is aligned with an axis of the drill string and another position in which the tube member is offset from the axis of the drill string. These embodiments are particularly although not exclusively suited for smaller surface drilling platforms that are typically used for drilling bore holes of between about 89 to 165 millimetres in diameter, commonly referred to as “crawler drilling rigs”.

[0028] In embodiments, the tube member is movable axially while remaining coupled to the mast for lowering the tube member into the bore hole and for raising the tube member out of the bore hole. Preferably, the bore hole sleeve apparatus includes a hydraulic actuator to axially translate, for example to lift and lower, the tube member relative to the bore hole. These embodiments are particularly although not exclusively suited for larger surface drilling platforms that are typically used for drilling bore holes of between about 165 to 351 millimetres in diameter, commonly referred to as “platform drilling rigs”. [0029] In embodiments, the drilling apparatus further includes a sheet deployment apparatus for deploying a flexible sheet into the open end of the tube member located in the bore hole.

[0030] In embodiments, the sheet deployment apparatus includes a sheet former adapted to form a flat flexible sheet into a curved form and to feed the curved sheet into the open end of the tube member located in the bore hole.

[0031] Preferably, the forming apparatus includes a wide mouth inlet and tapers to a narrower round outlet to define a path for a flexible sheet and a feeding mechanism for feeding the flexible sheet through the inlet and the round outlet and into the tube member.

[0032] Preferably, the drilling apparatus includes a store of a plurality of the flexible sheets and a picker is adapted to pick the sheets one at a time. The flexible sheets can be flat and arranged in a stack or the flexible sheet can be pre-rolled sheet and including a tie that holds each of the pre-rolled sheets in the rolled form. In embodiments, the deployment device is adapted to pick one of the pre-rolled sheets and feed the pre-rolled sheet into the bore hole through the tube member.

[0033] Preferably, the drilling apparatus further includes a shroud adapted to be substantially sealed with the longitudinal internal passage of the tube member for directing cuttings and/or bailings that emerge from the bore hole during drilling.

[0034] Preferably, the shroud includes an axial passageway for receiving the drilling string therethrough and an outlet opening that is oriented transversely to the axial passageway.

[0035] Preferably, the outlet opening is adapted to be coupled to a flexible conduit of a vacuum apparatus. [0036] Preferably, the shroud is mounted to the mast and an actuator is adapted to translate the shroud upwards and downwards in a linear range of motion.

[0037] Preferably, the drilling apparatus further includes an outlet located next to or underneath the mobile platform for directing cuttings and/or bailings that emerge from the bore hole during drilling to a pile adjacent to or beneath the mobile platform.

[0038] Embodiments of the drilling apparatus include various types of mobile drilling apparatus comprising a mobile, tracked platform comprising a drill mast supporting a drill string and accompanying percussion rotary air blast drilling apparatus. In some embodiments, such mobile drilling apparatus include smaller surface drilling platforms that are typically used for drilling bore holes of between about 89 to 165 millimetres in diameter, commonly referred to as “crawler drilling rigs” and produced by manufacturers such as Sandvik, Epiroc, Komatsu and Caterpillar. In other embodiments, such mobile drilling apparatus include larger surface drilling platforms that are typically used for drilling bore holes of between about 165 to 351 millimetres in diameter, commonly referred to as “platform drilling rigs” produced by manufacturers such as Sandvik, Epiroc, Komatsu and Caterpillar.

[0039] Embodiments of the drilling apparatus comprising the shroud for directing cuttings and/or bailings that emerge from the bore hole during drilling are advantageous when implemented in classes of larger mobile drilling platforms, such as those typically for drilling larger diameter bore holes of 165 to 351 millimetres. Such existing drilling platforms can comprise cuttings and/or bailings management systems comprising simply surrounding the bore hole with flexible curtains attached to and draping down from beneath the platform. Embodiments of the invention can replace or complement such existing systems. [0040] In embodiments, the drilling apparatus includes a system for injecting a composition between the external surface of the tube member and the surrounding wall of the bore hole.

[0041] Preferably, the system for injecting a composition includes a store of the composition and coupled to a network of conduits and openings formed in the tube member. Thus, when the tube member is located within the bore hole the composition comes out of the openings and enters the space between the tube member and the bore hole or penetrates the surrounding loose rock fragments or both.

[0042] In another aspect, the invention provides a method of drilling a bore hole including: coupling a tube member to a mast of a mobile drilling rig, the tube member including a longitudinal internal passage for receiving a drill string therethrough; boring a hole into a bench surface and lowering the tube member within the collar region of the bore hole, the tube member including an external surface for facing outwardly against a wall of the bore hole.

[0043] In another aspect, the invention provides a method of providing a collar support apparatus into a bore hole, the method including: coupling a tube member to a mast of a mobile drilling rig, the tube member including a longitudinal internal passage for receiving a drill string therethrough; boring a hole into a bench surface and lowering the tube member within the collar region of the bore hole, the tube member including an external surface for facing outwardly against a wall of the bore hole; providing a support in the bore hole for stabilising the collar region of the bore hole; and removing the tube member from the bore hole. [0044] Preferably, providing a support in the bore hole includes inserting a collar support apparatus comprised of a flexible sheet of material into the longitudinal internal passage of the tube member and; wherein removing the tube member from the bore hole leaving behind the collar support apparatus within the bore hole.

[0045] Preferably, moving the mast relative to the tube member includes moving the mast between a position in which the tube member is aligned with an axis of the drill string and another position in which the tube member is offset from the axis of the drill string while the tube member and the mast remain coupled together.

[0046] Preferably, removing the tube member from the bore hole includes manoeuvring the mast to raise the tube member out of the bore hole.

[0047] Preferably, coupling the tube member to the mast includes horizontally translating the mast relative to the tube member. In an embodiment, uncoupling the tube member and the mast also includes horizontally translating the mast relative to the tube member.

[0048] Preferably, an adapter secured to the mast includes a slot and an end of the tube member includes a flange, whereby the horizontal movement of the mast relative to the tube member causes the flange to move into or out of the slot.

[0049] In embodiments, providing a support in the bore hole for stabilising the collar region of the bore hole includes injecting a composition between the external surface of the tube member and the surrounding wall of the bore hole.

[0050] In embodiments, the injected composition cures or otherwise hardens or solidifies to become self-supporting or binds the loose rock fragments to form a composite collar support. [0051] In yet another aspect, the invention provides a sheet forming device adapted to form a flat flexible sheet into a curved form and to feed the curved sheet into a tube member located within the collar region of a bore hole, the device including: a forming apparatus adapted to form a flat flexible sheet into a curved form; and a feed mechanism for feeding the curved sheet into the open end of a tube member located within the collar region of a bore hole.

[0052] Preferably, the forming apparatus includes a wide mouth inlet and tapers to a narrower round outlet to define a path for the flexible sheet wherein the feeding mechanism feeds the flexible sheet through the inlet and the outlet of the forming apparatus and into the tube member.

[0053] Preferably, a plurality of the flexible sheets are arranged in a stack from which the feed mechanism is configured to pick the sheets one at a time.

[0054] Preferably, the sheet forming device is configured for attachment to a mast of a bore hole drilling apparatus.

BRIEF DESCRIPTION OF THE FIGURES

[0055] The present invention will now be described in more detail with reference to preferred embodiments illustrated in the accompanying figures, wherein:

[0056] Figure 1 illustrates a perspective view of a tube member of a bore hole sleeve apparatus in accordance with an embodiment of the invention;

[0057] Figure 2 illustrates a side view of a longitudinal section of the tube member of Figure 1;

[0058] Figure 3 illustrates a perspective view of an adapter of an embodiment of the bore hole sleeve apparatus; [0059] Figure 4 illustrates a top view of a cross section of the adapter of Figure

3;

[0060] Figure 5 illustrates an oblique perspective view of a drilling apparatus including a mobile drilling rig with a hydraulic arm and a drilling mast attached thereto and the adapter of Figures 3 and 4 connected to the mast and the tube member of Figures 1 and 2 coupled to the adapter;

[0061] Figure 6 illustrates a frontal perspective view of the drilling apparatus of figure 5;

[0062] Figures 7 to 14 are a set of frontal views of a portion of the drill mast and the bore hole sleeve apparatus embodiment of the preceding figures 1 to 6 illustrating a sequence of steps in a method of drilling a bore hole in accordance with an embodiment of the invention and a method of providing a collar support apparatus into the bore hole in accordance with an embodiment of the invention;

[0063] Figure 15 illustrates a front view of the collar support apparatus of Figures 7 to 14 in a flat configuration;

[0064] Figure 16 illustrates a front view of the collar support apparatus of Figures 7 to 14 in a curved configuration;

[0065] Figure 17 illustrates an oblique perspective view of a drilling apparatus including a mobile drilling rig with a hydraulic arm and a drilling mast attached thereto similar to the embodiment of Figure 5 further including a sheet forming apparatus adapted to form a flat flexible sheet into a curved form and to feed the curved sheet into the open end of the tube member located in the bore hole;

[0066] Figures 18 and 19 are a set of frontal views of a portion of the drilling apparatus of Figure 17 including a portion of the drill mast, sheet forming apparatus and a collar support apparatus comprised of a curved flexible sheet and illustrating a sequence of steps of forming a flat flexible sheet into the curved form and feeding the curved sheet into the open end of the bore hole sleeve apparatus located in the bore hole and withdrawing the sleeve apparatus from the bore hole to leave behind the collar support apparatus;

[0067] Figure 20 illustrates an embodiment of the drilling apparatus of Figure 5 further including a shroud adapted to be substantially sealed with the longitudinal internal passage of the tube member for directing cuttings and/or bailings that emerge from the bore hole during drilling;

[0068] Figure 21 illustrates an embodiment of the drilling apparatus of Figure 5 and further including a shroud adapted to be substantially sealed with the longitudinal internal passage of the tube member, wherein the shroud is coupled to a flexible conduit of a vacuum apparatus, for directing cuttings and/or bailings that emerge from the bore hole during drilling;

[0069] Figures 22 to 25 illustrate an embodiment of a drilling method by reference to another embodiment of the drilling apparatus of the invention including a class of surface drilling platform that is typically used for drilling larger diameter bore holes of between about 165 and 351 millimetres in diameter, wherein the sleeve apparatus includes the a hydraulic actuator to lift and lower the tube member axially relative to the bore hole and wherein a hydraulic actuator is adapted to lift and lower the shroud relative to the tube member for directing cuttings and/or bailings that emerge from the bore hole during drilling;

[0070] Figure 26 illustrates another embodiment of the drilling method and apparatus adapted to pick one pre-rolled and tied flexible sheet at a time and deploy the sheet pre-rolled sheet into the tube member within the bore hole;

[0071] Figure 27 illustrates and a bottom view of the surface drilling platform embodiments of Figures 22 to 26 illustrating an arrangement of curtains attached to and draping down from beneath the platform to contain cuttings and/or bailings that are directed by the shroud underneath the drilling platform; and [0072] Figures 28 and 29 illustrate another embodiment of a method of stabilising the collar of the bore hole including injecting a stabilisation composition into the wall of the bore hole or the loose rock fragments surrounding the bore hole in the collar region.

[0073] The invention will now be described in further detail with reference to the embodiments illustrated in the Figures.

DETAILED DESCRIPTION

[0074] Blast-hole drilling is a technique that is used in the extraction of minerals and rock products from surface mines and quarries. A bore-hole drill produces bore holes according to a predetermined pattern and depth. The holes are then charged with explosive and the minerals and rocks are blasted and fragmented for subsequent removal by excavators for further processing. Significant quantities of loose rock fragments, or “preconditioned” material, can remain on the bench from the sub-drilled region after achieving the Reduced Level (RL). A preconditioned layer depth of up to 4 metres or more can improve the efficiency of the comminution process by maximising the volume of fine fragmentation that results from the subsequent blasting operation.

[0075] Referring to Figures 5 and 6, the present invention is directed to a sleeve apparatus 100 that is adapted for use with a drilling rig 10 for drilling bore holes. Referring to Figures 1 to 6 and 9 to 13, the sleeve apparatus 100 includes a tube member 110 adapted in use to be located within a bore hole in a manner that will be described in further detail below. The tube member 110 includes a longitudinal internal passage 120 for receiving a drill string of the drilling rig therethrough. The tube member 110 also includes an external surface 125 for facing outwardly against a wall of the bore hole.

[0076] The sleeve apparatus 100, in particular the tube member 110, is adapted to support the collar of the bore hole 2 during drilling and immediately after drilling and before a collar support apparatus can be located in position within the collar of the bore hole 2. In some embodiments, the sleeve apparatus 100, and in particular the tube member 110, is adapted to receive a collar support apparatus therewithin. The tube member 110 can thereby assist in the steps of forming the normally flat collar support apparatus into a curved form and inserting the collar support apparatus into the bore hole.

Drilling Rig

[0077] Figures 5 and 6 illustrate an exemplary mobile drilling rig 10 for drilling bore-holes 2. The illustrated drilling rig 10 is a percussive top-hammer type drilling rig. However, it is to be appreciated that the present invention has broader application to other types of drilling rigs such as down the hole (DTH) and rotary drilling rigs. The embodiment of the mobile drilling rig 10 illustrated in the figures is a class of surface drilling platform that is typically used for drilling bore holes of between about 89 to 165 millimetres in diameter, commonly referred to as “crawler drilling rigs”. However, it is to be appreciated that embodiments of aspects of the invention are applicable to classes of larger surface drilling platforms that are typically used for drilling bore holes of between about 165 to 351 millimetres in diameter, commonly referred to as “platform drilling rigs”. Platforms of the smaller and larger classes are known to originate from various manufacturers such as Sandvik, Epiroc, Komatsu and Caterpillar to name but a few.

[0078] The drilling rig 10 comprises a self-propelled vehicle 12 including a hydraulic arm 14 that supports a mast 20. The mast 20 itself is adapted to support a drill string 30 comprised of a plurality of drill rods 35 and a bit 37 at the end of the drill string 30. The drill rods 35 are coupled together by threaded connections therebetween.

[0079] In one aspect, the invention is directed to a bore hole sleeve apparatus 100 adapted to be coupled to the mast 20 in a manner that will be described in more detail below. In another aspect, the invention is directed to the combination of the mobile drilling rig 10 and the bore hole sleeve apparatus 100.

[0080] The mast 20 carries a drilling head 25 including a reciprocating piston or hammer assembly and a rotary assembly which together are adapted to apply percussive force and rotational torque to the drill string 30. The drilling head 25 can be raised and lowered by a hydraulically driven up-down feed system 29 to enable pipes or rods to be removed from, or added to, the drill string.

[0081] The mast 20 contains a store 27 of a plurality of the drill rods 35. During a drilling operation, when the top of the uppermost drill rod 35 reaches the bottom of the mast 20 a subsequent drill rod 35 is swung into position by the drill rod feed system 29 and into axial alignment with the uppermost drill rod 35 of the drill string 37. The drilling head 25 engages and rotates the subsequent drill rod 35 to threadably couple with the top of the drill rod 35 below. The drilling head 20 then resumes drilling by applying percussive force and rotational torque to the drill string 30.

Bore Hole Sleeve Apparatus

[0082] As illustrated in Figures 9 to 13, the sleeve apparatus 100 includes the tube member 110 that in use is adapted to be located within the bore hole 2 that has been drilled or is in the process of being drilled by the drilling rig 10. Preferably, the tube member 110 is formed of a rigid and durable material such as metal (e.g. mild steel). The tube member 110 is configured to be releasably coupled to the bottom of the mast 20. When coupled to the mast 20, the longitudinal internal passage 120 of the tube member 110 is adapted to be aligned with the axis of the drill string 30 to receive the drill string 30 therethrough.

[0083] The external surface 125 of the tube member 110 is adapted for facing outwardly against a wall of the bore hole 2. The diameter of the external surface 125 of the tube member 110 is ideally slightly greater, or slightly less or about the same as the diameter of the drill bit 37. The diameter of the external surface 125 of the tube member 110 is ideally slightly greater, or slightly less or about the same as the diameter of the bore hole 2 to be formed thereby. Accordingly, different diameter tube members 110 may be provided for use with different diameter drill bits 37 and/or different diameter bore holes 2. [0084] In some bore hole drilling operations, a preconditioned layer depth of up to 4 metres or more can be employed. The section of the bore hole 2 in the preconditioned layer is sometimes referred to as the “collar”. The preconditioned layer is comprised of fragmented rock which can consist of a wide range of particle sizes including fine, medium, and coarse with ranges of 1 mm to 100 mm or more. The bore hole sleeve apparatus 100 is adapted to provide temporary support for the wall of the bore hole 2 in the collar region, both during the drilling operation and after the bore hole has been drilled to the desired depth.

Coupling

[0085] In another aspect, the invention is directed to a coupling between the mast 20 of the drilling rig 10 and the tube member 110 for securing the tube member 110 to the mast 20. As will be apparent from the foregoing description, in embodiments disclosed herein, the coupling is adapted for permitting movement of the tube member 110 relative to the mast 20 between a position in which the tube member 110 is aligned with an axis of the drill string 30 and another position in which the tube member 110 is offset from the axis of the drill string 30 while the tube member 110 and the mast 20 remain coupled together.

[0086] Referring to Figures 1 and 2, the tube member 110 has openings 112,

114 at opposite ends 111, 113 thereof. The longitudinal passage 120 extends between the openings 112, 114. At one of the ends 111, the tube member 110 includes a flange 115 extending radially outwardly from an edge around the opening 112. The flange 115 is comprised of a plate which may be welded or otherwise fixed or formed integral with the end 111 of the tube member 110. The flange 115 illustrated in the Figures is a substantially planar member fixed, such as by welding, at the end 111 of the tube member 110. The flange 115 has a polygonal shape with opposite lateral edges 117, 118. The opposite lateral edges include parallel edge sections 117a, 118a and tapering sections 117b, 118b. The tapering edge sections 117b, 118b provide a narrower width dimension at one end 119 of the flange 115. In other embodiments, the flange

115 may be round or in part round or oval shaped. Protrusions 116 extend from a lower surface of the flange 115 that, in use, are adapted to engage the surface of the bench. The protrusions 116 function to maintain the flange 115 spaced above the surface of the bench, or proud of the surface.

[0087] Referring to Figures 3 and 4, an adapter 150 is provided that, as illustrated in Figures 5, 6 and 8 to 14, is configured to be secured to the mast 20. The adapter 150 includes a foot pad 155 that in some circumstances is adapted to engage the bench surface during a drilling operation to at least partially support and maintain the stability of the mast 35. A riser 157 extends upwardly from foot pad 155 and is adapted to be coupled to the end of the mast 20. The riser 157 can be configured to substitute and fit in place of the riser of a proprietary foot assembly for the mast 20 of the drill rig 10, such as the proprietary foot assembly of Figure 7. In other words, the adapter 150, including the foot pad 155 and riser 157, can be configured to be a straight swap for the proprietary foot assembly 9, such as is illustrated in Figure 7. In other embodiments, the adapter 150 is configured without a foot pad 155 or is configured without a foot pad 155 and riser 157 and instead is coupled to the riser and foot pad of the proprietary foot assembly 9.

[0088] The adapter 150 also includes a horizontally oriented slot 160 defined between horizontally oriented upper and lower plates 164, 174. The slot 160 is closed at laterally opposite sides 161 , 163 and is open to one end 162. In an embodiment not illustrated, the lower plate 174 flares outwardly, however both the upper and lower plates 164, 174 can flare outwardly at the open end 162 of the slot 160 or neither can be flared outwardly. The upper and lower plates 164, 174 are located horizontally adjacent to the foot pad 155.

[0089] The riser 157 is formed with a vertical upright section 156 and a pair of opposite gusset sections 158, 159 extending between the upright section and the upper and lower plates 164, 174. The gusset sections 158, 159 provide structural support and rigidity for the connection between the vertical upright section 156 and the upper and lower plates 164, 174.

[0090] The upper and lower plates 164, 174 each include a central opening 165, 175 that, when coupled to the mast 20, are both axially aligned with the drill string 30. The gusset sections 158, 159 are arranged opposite each other and are spaced apart by a distance at least equal to or greater than a diameter of the central opening 165 in the upper plate 164. The central opening 175 of the lower plate 174 opens to the side 162 so that the flange 115 can be received into the slot 160 through the opening on the side 162 and be positioned between the upper and lower plates 164, 174 with the tube member 110 extending downwardly through the central opening 175 in the lower plate 174 as illustrated in Figures 4 and 5. The horizontally oriented slot 160 and the flange 115 together provide a slot mount coupling between the tube member 110 and the adapter 150. It will be appreciated that in some circumstances the tube member 110 and the adapter 150, and in turn the mast 20, can be releasably coupled by horizontally translating the adapter 150 relative to the tube member 110.

[0091] As the adapter 150 translates horizontally relative to the tube member 110 the lower plate 174 of the adapter 150 is received in the space between the flange 115 and the surface of the bench maintained by the protrusions 116. Thus, the protrusions 116 elevate the flange 115 above the surface of the bench to allow flange 115 to locate below and engage the bottom surface of the flange 115.

[0092] The tube member 110 and the adapter 150 are configured so that the tube member 110 is movable between a position in which the tube member 110 is aligned with an axis of the drill string 30 and another position in which the tube member 110 is offset from the axis of the drill string 30. This can be achieved through different means. However, in the embodiment illustrated in the figures this is achieved by the relative movement of the flange 115 relative to the horizontally oriented slot 160. During the movement of the tube member 110 and the adapter, the flange 115 is located within the slot 160 between the upper and lower plates 164, 174 of the adapter 150.

[0093] The height of the protrusions 116 extending from the flange 115 of the tube member 110 is greater than the combined height of the lower plate 174 and the foot pad 155, and any protrusions associated with the foot pad. The protrusions 116 elevate the flange 115 above the surface of the bench by a height sufficient to allow the lower plate 174 and any protrusions associated with the foot pad 155, if any, to locate under the flange 115 and still be clear of the surface of the bench. Accordingly, the protrusions 116 of the tube member 110 have a height sufficient so that when resting on the bench surface the adapter 150 can be clear of the bench surface and can move horizontally relative to the tube member 110 while the flange 115 is located within the slot 160.

[0094] In use, the drill string 30 passes through central openings 165, 167 of the upper and lower plates 164, 174 and, in turn, through the longitudinal internal passage 120 within the tube member 110 as illustrated in Figures 8 to 10.

[0095] In another embodiment, the adapter 150 may be configured to fit with the proprietary foot assembly. In such an embodiment, the adapter 150 may not include the foot pad 155 or the riser 157 and instead may be largely comprised only of the horizontally oriented upper and lower plates 164, 174.

Drilling Method

[0096] In Figures 9 to 14, a frontal section of an open end at the top of a single bore hole 2 is illustrated. However, it is to be appreciated that a multitude of such bore holes 2 would be drilled on a bench for a single blasting operation. The bore hole 2 can be drilled with a diameter as large as 270 to 311 millimetres or as much as 350 millimetres or more and to depths of as much as 50 metres or more. After drilling, the bore hole 2 is filled with explosive material appropriate for the ground conditions, such as a mixture of ammonium nitrate and fuel oil (ANFO) or an emulsion or a mixture thereof and is primed for detonation.

[0097] An operator of the drill rig 10 causes the hydraulic arm 14 to manoeuvre the mast 20 with the adapter 150 secured thereto. The tube member 110 is preferably supported upright, such as on a vehicle or some other support structure, with the flange 115 at the top. The mast 20 is manoeuvred so that the slot 160 is oriented in alignment with the flange 115. The mast 20 is then manoeuvred relative to the tube member 110 so that the flange 115 is received into the slot 160 whereby the tube member 110 and the adapter 150, and the mast 20 connected thereto, are coupled together.

[0098] The width dimension of the slot 160 between the closed laterally opposite sides 161, 163 is greater than the width dimension between the parallel edge sections 117a, 118a of the flange 115. The tapering edge sections 117b, 118b provide a narrower width dimension at one end 119 of the flange 115 to assist in guiding the flange 115 into the slot 160.

[0099] The drilling rig 10 is moved into position adjacent to the location at which a bore hole 2 is to be drilled. As illustrated in Figure 8 the drill string 30 is then lowered down through the tube member 110 and into engagement with the surface of the bench. The drill head 25 is activated and because the top layer of material is preconditioned the drill bit 37 penetrates relatively easily. The operator causes the hydraulic arm 14 to lower the mast 20 which in turn lowers the tube member 110 until the protrusions 116 extending from the lower surface of the flange 115 engage the surface of the bench as illustrated in Figure 9. At this point, the tube member 110 is almost completely below the surface of the bench with the external surface 125 of the tube member 110 facing outwardly against the wall of the bore hole 2 and the flange 115 spaced above the surface of the bench, or proud of the surface of the bench.

[00100] Drilling continues until the desired hole depth is reached. The drill string 30 is then withdrawn from the bore hole 2 as illustrated in Figure 10. As illustrated in Figure 11 the mast 20 is manoeuvred horizontally so that the flange 115 moves relative to the slot 160.

[00101] In an embodiment, not illustrated in the figures the mast 20 is manoeuvred horizontally so that the flange 115 moves out of the slot 160 whereby the tube member 110 and the adapter 150, and the mast 20 connected thereto, are uncoupled. In the embodiment illustrated in the figures, the mast 20 is manoeuvred horizontally so that the flange 115 moves relative to the slot 160 but still remains within the slot 160 between the upper and lower plates 164, 174 of the adapter 150. Embodiments in which the flange 115 remains within the slot 160 are advantageous in that they do not require the operator to reposition the lower plate 174 of the adapter 150 in the relatively small space between the flange 115 and to surface of the bench.

Collar Support Apparatus

[00102] The bore hole sleeve apparatus 100 is adapted for use with a collar support apparatus 200 for preventing loose rock fragments in the preconditioned layer from falling or collapsing into the bore hole, such as the apparatus 200 illustrated in Figures 15 and 16.

[00103] The collar support apparatus 200 includes a flexible sheet 210 including a pair of opposite surfaces 211, 212 and a pair of spaced apart longitudinally extending side edges 214, 216 and a pair of spaced apart laterally extending end edges 215, 217. The normally flat sheet 210 being adapted, in use, to be formed into a curved, substantially cylindrical shape to define a longitudinal passage 218 extending between openings at longitudinally opposite ends 211 , 219.

[00104] The flexible sheet 210 is preferably comprised of a resilient material, such as a resiliently flexible polymeric material which may be reinforced with nylon or some other flexible reinforcement. The sheet 210 is preferably rectangular in shape such that the side edges 214, 216 are parallel and the end edges 215, 217 are also parallel. The side edges 214, 216 are tapered at one end. The sheet 20 includes a series of apertures 213 that are arranged in laterally spaced apart and longitudinally aligned pairs for use as hand holds and for hanging the collar support apparatus 200 when not in use.

[00105] As illustrated in Figure 12, the collar support apparatus 200 can be inserted into the longitudinal internal passage 120 within the tube member 110 when it is located within the bore hole 2. As illustrated in Figures 12 to 14, the tube member 110 can then be removed from the bore hole 2 by carrying out the reverse of the process described above. That is, by manoeuvring the mast 20 horizontally so that the flange 115 moves within the slot 160 until the flange 155 is substantially fully within the slot 160. The mast 20 is then lifted to bring the tube member 110 up out of the bore hole 2 leaving behind the collar support apparatus 200 within the collar region of the bore hole 2. The resilient properties of the material from which the sheet 210 is formed allow the sheet 210 to expand and assume a substantially cylindrical form within the bore hole 2 as illustrated in Figure 14.

[00106] One of the surfaces 211 , 212 of the sheet 210 faces outwardly against the inwardly facing surface of the bore hole 2 and forms a barrier preventing surrounding loose rock fragments from falling or collapsing into the bore hole 2. Because the material from which the sheet 210 is formed is resilient the sheet 210 tends towards assuming its flat form and this property causes the surface 211 , 212 of the sheet 210 facing outwardly to apply pressure against the inwardly facing surface of the bore hole 2. At least part of the collar support apparatus 200 may also protrude above the bench surface to provide additional protection against surrounding loose rock fragments on the bench surface from falling or collapsing into the bore hole 2.

[00107] The longitudinal dimension of the sheet210 between the longitudinally opposite end edges 215, 217 may be 1 metre, 1.5 metres, 2, metres, 2.5 metres, 3 metres, 3.5 metres, 4 metres or more in length or any length in between. When positioned within the blast hole 2 the sheet 210 provides support for the internal surface of the bore hole 2 through a substantial portion of the wall of the bore hole 2 in the collar region.

[00108] The width of the sheet 210 between the pair of parallel side edges 214, 216 is preferably, though not necessarily, slightly more than the circumference of the bore hole 2. When the sheet 210 assumes the substantially cylindrical form within the bore hole 2 the side edges 214, 216 of the sheet 210 slightly overlap. However, in another embodiment, the side edges 214, 216 of the sheet do not overlap and are slightly spaced apart.

[00109] The drilling rig 10 is moved into position adjacent to the location at which the next bore hole 2 is to be drilled and the above described process is repeated. The collar support apparatus 200 remains in position within the blast hole 30 during a subsequent step of depositing explosives and other consumables into the bore hole 2. After the bore hole is charged and primed the collar support apparatus 200 can be removed from the bore hole 2 or partially withdrawn and formed into a funnel shape prior to depositing of stemming material into the bore hole 2.

[00110] Figures 17 to 19 illustrate another embodiment of the mobile drilling rig 310 for drilling the bore-hole 2. The illustrated drilling rig 310 is similar to the drilling rig 10 of Figures 5 and 6 and like reference numerals will be used to identify like features. The principal difference is that the drilling rig 310 further includes a deployment device 350 mounted to the mast 20 for forming a flat flexible sheet 210 into a curved form and inserting the curved sheet 210 into the bore hole sleeve apparatus 100 located within the collar region of the bore hole 2 to thereby form the collar support apparatus 200.

[00111] The deployment device 350 includes a plurality of the sheets 210 arranged in a stack 315. The stack 315 of the sheets 210 is supported on a frame 209. The device 350 includes a sheet picker and feeder 355 that is operable to pick an individual sheet 210 from the stack 315 and feed the sheet 210 into a vertical forming apparatus 330. In the embodiment illustrated in Figure 9, the picker and the feeder 355 includes an arrangement of driven rollers operable to pick one of the sheets 210 at a time from the stack 315 however an arrangement of belts. However, any mechanical arrangement that is adapted to pick one sheet 20 from the stack 315 and feed the sheet 20 to the vertical forming apparatus 330 can constitute another embodiment of the invention.

[00112] The forming apparatus 330 is operable to form the sheet 210 into the curved substantially cylindrical shape defining a longitudinal passage 218 extending between openings at longitudinally opposite ends 211 , 219. The forming apparatus 330 includes a wide mouth 331 and tapers to a narrower round outlet 333 to define a path 335 for a flexible sheet. A feeding mechanism feeds the flexible sheet 210 through the inlet 331 and the round outlet 333 and into the tube member 110.

[00113] The illustrated embodiment of the forming apparatus 330 includes a funnel shaped portion 332 defining the wide mouth 331 and transitioning into a cylindrically shaped portion 336 defining the narrower round outlet 333. The funnel shaped portion 332 and the cylindrically shaped portion 336 are defined by a side wall 338 preferably formed out of sheet metal or the like. Instead of the funnel shaped portion 332 the forming apparatus could comprise an elongated and substantially planar opening similar to the shape of the flat sheet 210 and gradually transitioning into the round shape of the cylindrically shaped portion 336. However, other mechanical arrangements adapted to be mounted to the mast 20 of the drilling rig 10 for picking a single sheet 210 from the stack 315 and forming the sheet 210 into a curved form and inserting the sheet into the tube member 110 are within the scope of the disclosure contained herein.

[00114] Referring to Figures 18 and 19, after the bore hole 2 has been drilled to the desired hole depth the drill string 30 is withdrawn from the bore hole 2 and the mast 20 is manoeuvred horizontally so that the flange 115 of the tube member 110 moves relative to the slot 160 and the drill string 30 is offset from the opening of the tube member 110. The round outlet 333 is thereby located above and in alignment with the open end of the tube member 110 as illustrated in Figures 18 and 19. The deployment device 350 is activated to whereby a single sheet 210 is picked from the stack 315 and formed into a curved form and inserted into the tube member 110 located within the bore hole 2 as illustrated in Figure 19. The deployment device 350 includes a further feed mechanism 339 comprised of one or more driven rollers or belt drive located at the outlet 333 for inserting the curved sheet 210 a desired depth into the tube member 110 and the open end of the bore hole 2.

[00115] The tube member 110 may then be withdrawn from the bore hole 2 in the same manner described above with reference to the process illustrated in embodiment of Figures 12 to 14. That is, by manoeuvring the mast 20 horizontally so that the flange 115 moves within the slot 160 until the flange 155 is substantially fully within the slot 160. The mast 20 is then lifted to bring the tube member 110 up out of the bore hole 2 leaving behind the collar support apparatus 200, comprised of the curved sheet 210, within the collar region of the bore hole 2.

[00116] The deployment device 350 may be mounted to the mast 20 of the drilling rig 310 or in another embodiment may be mounted to a separate vehicle (not shown) or a trailer (not shown) coupled to a vehicle or any other mobile apparatus adapted to be manoeuvred around a site. The vehicle or other mobile apparatus may be a truck that is operable manually by a driver or in an embodiment is configured to operate autonomously or semi-autonomously. The vehicle or other mobile apparatus may comprise a control module that includes a GPS location device and is adapted for controlling a drive means and steering means of the vehicle. The control module is adapted to receive or be programmed with the coordinates of the location of one or more of a plurality of blast holes and to autonomously manoeuvre the deployment device 350.

[00117] Figures 20 and 21 illustrate an embodiment comprising a moveable shroud 400 for directing cuttings and/or bailings that emerge from the bore hole 2 during the drilling operation. The shroud 400 is comprised of a body 410 comprising a hollow internal cavity with an opening at the bottom and at the top. The top of the body 410 is adapted to be mounted to a moveable shroud adapter 420 that is coupled to the mast 20 of the drilling rig 10. The moveable shroud adapter 420 is adapted to translate upwards and downwards in a linear range of motion of about 50cm. The shroud 400 is formed out of durable material such as a metal alloy and has a conical upper part 405 and a flexible and durable plastic or rubber lower boot 407. The boot 407 is sealed around the opening at the bottom of the body 410. The shroud 400 is positioned in alignment with the axis of the drill string 30 and the openings at the top and the bottom of the shroud 400 permit the drill string 30 to pass therethrough.

[00118] In use, the moveable shroud adapter 420 is adapted to lower the shroud 400 down towards the adapter 150 so that the boot 407 contacts with the upper plate 164. The boot 407 of the adapter thereby provides a seal around the central opening 165 of the upper plate 164 of the adapter 150. The shroud 400 is aligned with the longitudinal passage 120 of the tube member 110 so that the drill string 30 may pass therethrough to permit drilling to commence. The shroud 400, including the boot 407, are sized and configured to be positionable between the gusset sections 158, 159 of the adapter 150.

[00119] During drilling, as illustrated in Figures 9 and 10, cuttings and/or bailings that emerge from the bore hole 2 travel up through the longitudinal passage 120 of the tube member 110 and emerge out of the opening 112. The cuttings and/or bailings that emerge out of the opening 112 of the tube member 110 are directed up into the body 410 of the shroud 400. The shroud 400 includes an outlet opening 415 for the cuttings and/or bailings to exit the body 410 of the shroud. The outlet opening 415 is oriented transversely to the axis of the drill string 30.

[00120] In the embodiment illustrated in Figure 20 the outlet opening 415 is uncovered so that the cuttings and/or bailings can freely emerge from the outlet opening 415 and be distributed onto the bench surface adjacent to the bore hole 2 being drilled. This embodiment is suited for wet drilling operations where a slurry comprising the cuttings and/or bailings mixed with water emerge from the bore hole 2.

[00121] In the embodiment illustrated in Figure 21 , the outlet opening 415 is coupled to a flexible hose 425 that in turn is coupled to a vacuum pump system. The cuttings and/or bailings that emerge from the outlet opening 415 are drawn through the flexible hose 425 and are deposited on the bench surface in a pile located a sufficient distance from the bore hole 2 being drilled. This embodiment is suited for dry drilling operations the cuttings and/or bailings that emerge from the bore hole 2 are dry and comprise a significant proportion of dry particulates.

[00122] The opening at the top of the body 410 of the shroud 400 includes a seal between the opening and the drill rods 35 comprising the drill string 30. The seal between the opening at the top of the body 410 of the shroud 400 and the drill rods 35 prevent cuttings and/or bailings that enter the shroud 400 from emerging from the opening at the top of the body 410 of the shroud 400. The seal may be comprised of a circular ring made of metal or of a durable polymer or rubber material. The seal is sized to within a relatively small tolerance around the external circumference of the drill rods 35.

Drilling Platform

[00123] Figures 22 to 27 illustrate another embodiment of mobile platform drilling rig 510 for drilling bore-holes 2. The illustrated drilling platform 510 can be for rotary or hammer drilling specifically designed for mining-duty although it is to be appreciated that embodiments of the invention may have broader application. The embodiment of the mobile drilling rig 510 illustrated in the figures is a class of surface drilling platform that is typically used for drilling larger diameter bore holes of between about 165 and 351 millimetres in diameter and are commonly referred to as “platform drilling rigs”. Platforms of these larger classes are known to originate from various manufacturers such as Sandvik, Epiroc, Komatsu and Caterpillar.

[00124] The drilling rig 510 comprises a self-propelled tracked platform 512 including a hydraulic arm that supports a mast 520. The mast 520 itself is adapted to support a drill string 530 comprised of one or a plurality of drill rods 535 and a bit 537 at the end of the drill string 530. The drill rods 535 are coupled together by threaded connections therebetween.

[00125] The mast 520 carries a drilling head including a reciprocating piston or hammer assembly and a rotary assembly which together are adapted to apply percussive force and/or rotational torque to the drill string 530. The drilling head 525 can be raised and lowered by a hydraulically driven up-down feed system to enable pipes or rods to be removed from, or added to, the drill string.

[00126] A bore hole sleeve apparatus 600 is adapted to be coupled to the mast 520 in a manner that will be described in more detail below. The sleeve apparatus 600 is similar to the sleeve apparatus embodiment 100 described above and so like reference numerals will be used in relation to like features. [00127] As illustrated in Figures 22 to 26, the sleeve apparatus 600 includes the tube member 110 that in use is adapted to be located within the bore hole 2 that has been drilled or is in the process of being drilled by the drilling rig 510. Similar to other embodiments, in the embodiment of Figures 22 to 27, an adapter 550 is secured to the platform 512 relative to the mast 520. The adapter 550 is similar in configuration to embodiments of the adapter 150 described above and so like reference numerals will be used for like features.

[00128] As illustrated in Figure 22, the adapter 550 supports and retains the sleeve apparatus 600 relative to the platform 512 such that the drill string 530 can pass axially therethrough. The bit 537 engages the bench surface to initiate drilling of the bore hole 2. The platform 512 includes a linear actuator, such as a hydraulic actuator, to axially translate and thereby raise and lower the adapter 550 and the sleeve apparatus 600 coupled thereto in the axial direction of the drill string 530 and the bore hole 2.

[00129] As illustrated in Figure 23, the sleeve apparatus 600 is lowered down into the bore hole 2 until the protrusions 116 extending from the lower surface of the flange 115 engage the surface of the bench. At this point, the tube member 110 is almost completely below the surface of the bench with the external surface 125 of the tube member 110 facing outwardly against the wall of the bore hole 2 and the flange 115 spaced above the surface of the bench, or proud of the surface of the bench.

[00130] The shroud adapter 420 and the moveable shroud 400 are coupled to the platform 512 to enable the shroud to be moved up and down in a linear range of motion. The shroud adapter 420 includes a linear actuator, such as a hydraulic actuator, is coupled to the shroud 400 to translate axially and thereby raise and lower the shroud 400. As illustrated in Figure 23, the shroud 400 is lowered down onto the sleeve apparatus 600 and provides a seal around the central opening 165 of the upper plate 164 of the adapter 550.

[00131] During drilling, as illustrated in Figures 24 and 27, cuttings and/or bailings that emerge from the bore hole 2 travel up through the longitudinal passage 120 of the tube member 110 and emerge out of the opening 112. The cuttings and/or bailings that emerge out of the opening 112 of the tube member 110 are directed up into the body 410 of the shroud 400. The outlet opening 415 of the shroud 400 directs cuttings towards the underneath of the platform 512. In Figures 22 to 27 the outlet opening 415 is coupled to a flexible hose 425, however, it is to be appreciated that there may be no hose and cuttings and/or bailings emerge directly from the outlet opening 415.

[00132] As illustrated in Figures 24 and 27, curtains 511 are located underneath the platform 415. Curtains 511 extend along the length of the platform 415 adjacent to the tracks 502 supporting the platform 415 to block cuttings and/or bailings from entering the tracks 502. A strip curtain 515 is extends transversely across the rear of the platform 415 between the tracks 502. Optionally, a further curtain 516 is provided beneath the part of the platform 512 supporting the mast 520 to contain any cuttings and/or bailings from that escape from the shroud 400 or that otherwise move forward underneath the platform 512.

[00133] When the desired bore hole 2 depth is reached, the drill string 530 is withdrawn and the shroud 400 is lifted. The deployment device 350 is mounted to the platform 512 and is adapted to pick one sheet 20 from a stack 315 and to form and feed the sheet 20 as a roll into the bore hole 2 through the tube member 110. The deployment device 350 includes an inclined chute 352 to direct the rolled-up sheet 20 into the tube member 110 and clear of the raised shroud 400.

[00134] In another embodiment, as illustrated in figure 26, a store of pre-rolled sheets 20 are supported on the platform 512. Each pre-rolled sheet 20 includes a tie 21 that holds each of the pre-rolled sheets 20 in the rolled form. The deployment device 350 is mounted to the platform 512 and is adapted to pick one of the pre-rolled sheets 20 and feed the pre-rolled sheet 20 into the bore hole 2 through the tube member 110. The tie 21 can be connected to a ripcord that when pulled will release the tie 21 and thereby allow the sheet 20 to open up and come into face-to-face contact against the wall of the bore hole 2. [00135] The platform 512 can then move to the location of the next bore hole 2 to be drilled and the aforementioned process is repeated.

Composite Stabilisation Support

[00136] Figures 28 and 29 illustrate another embodiment of a method of stabilising the collar of the bore hole 2. The tube member 110 of the bore hole sleeve apparatus 100 provides temporary support for the wall of the bore hole 2 in the collar region and acts as a form as a composition is injected and, in some embodiments can penetrate the surrounding wall of the bore hole 2. The composition is injected and cures or otherwise hardens or solidifies to become self-supporting or binds the loose rock fragments to form a composite collar support 613.

[00137] The composition, which can be a fluid, is injected down a line 610 that is coupled to a network of conduits and openings 612 formed in the tube member 110. Thus, when the tube member 110 is located within the bore hole 2 the injected fluid comes out of the openings 612 and enters the space between the tube member 110 and the bore hole 2 or penetrates the surrounding loose rock fragments or both. The tube member 110 remains in the bore hole 2 for a period of time sufficient for the composition to harden, cure, solidify to become self-supporting or otherwise bind together the surrounding fine and coarse aggregate material to form the composite collar support 613.

[00138] In the time taken for the drilling operation to be completed, the composition will have cured and the bore hole sleeve apparatus 100 can then be withdrawn from the bore hole 2. A small rotation movement may be applied to the bore hole sleeve apparatus 100 to crack adhesion with the surrounding composite collar support 613.

[00139] The composition may be comprised of material, such as a polymer or resin, injected as a liquid and that subsequently hardens to for a structural, self- supporting sleeve between the tube member 110 and the bore hole 2. Alternatively, the composition may be comprised of material, such as a polymer or resin, injected as a liquid and that penetrates into the surrounding fine and coarse aggregate material (i.e. preconditioned material) to form the composite collar support 613.

[00140] The composition may include a polyurethane resin, a cross-linked polymer or resin, epoxy, polyester or phenolic resin or it may comprise a mineral binder such as Portland cement.

[00141] Although the disclosure has been described with reference to specific examples, it will be appreciated by those skilled in the art that the disclosure may be embodied in many other forms, in keeping with the broad principles and the spirit of the disclosure described herein.

Claims

Claims:

1. A bore hole sleeve apparatus for a bore hole drill, the sleeve apparatus including: a tube member adapted to be coupled to a mast of a mobile bore hole drill and to be positioned within the collar region of a bore hole, the tube member including a longitudinal internal passage for receiving a drill string therethrough and an external surface for facing outwardly against a wall of the bore hole.

2. The sleeve apparatus of claim 1 , wherein the tube member and the mast include a coupling for securing the tube member to the mast.

3. The sleeve member of claim 2, wherein the coupling is adapted for releasably securing the tube member to the mast.

4. The sleeve apparatus of claim 2 or claim 3, wherein the coupling is adapted for permitting movement of the tube member relative to the mast between a position in which the tube member is aligned with an axis of the drill string and another position in which the tube member is offset from the axis of the drill string while the tube member and the mast remain coupled together.

5. The sleeve apparatus of any one of claims 2 to 4, wherein the coupling includes a slot mount coupling.

6. The sleeve apparatus of any one of claims 2 to 5, wherein the coupling includes an adapter member secured to the mast that includes a slot for receiving a flange at an end of the tube member.

7. The sleeve apparatus of claim 6, wherein the slot is defined by a pair of opposing plates that, in use, are oriented substantially parallel with the bench surface.

8. The sleeve apparatus of claim 6 or claim 7, wherein the flange is adapted to move within the slot between a position in which the tube member is aligned with an axis of the drill string and another position in which the tube member is offset from the axis of the drill string.

9. The sleeve apparatus of claim 7 or claim 8, wherein the pair of plates each include an opening for receiving the drill string therethrough and for alignment with the longitudinal internal passage of the tube member.

10. The sleeve apparatus of claim 9, wherein the opening through a lower one of the plates is open to one side of the plate for receiving the tube member.

11. The sleeve apparatus of any one of claims 6 to 10, wherein one or more protrusions extend from the flange for engaging the bench surface and for maintaining a gap between the flange and the bench surface.

12. The sleeve apparatus of any one of the preceding claims, wherein the tube member is self-supporting within the collar of the bore hole and is adapted for receiving a collar support apparatus within the longitudinal internal passage.

13. The sleeve apparatus of any one of the preceding claims, wherein the tube member includes a rigid, cylindrically shaped body portion with openings at opposite ends and the longitudinal internal passage extending therebetween.

14. A drilling apparatus, including a mobile platform; a mast disposed on the platform including a support for a drill string; a drill string rotation and driving mechanism for driving the drill string to bore a hole into rock; a bore hole sleeve apparatus including a tube member coupled to the mast for positioning within the collar region of a bore hole, the tube member including a longitudinal internal passage for receiving the drill string therethrough and an external surface for facing outwardly against a wall of the bore hole.

15. The drilling apparatus of claim 14, wherein the tube member is movable while remaining coupled to the mast between a position in which the tube member is aligned with an axis of the drill string and another position in which the tube member is offset from the axis of the drill string.

16. The drilling apparatus of claim 14 or claim 15, wherein the tube member is movable axially while remaining coupled to the mast for lowering the tube member into the bore hole and for raising the tube member out of the bore hole.

17. The drilling apparatus of any one of claims 14 to 16, including a sheet deployment apparatus for deploying a flexible sheet into the open end of the tube member located in the bore hole.

18. The drilling apparatus of claim 17, wherein the sheet deployment apparatus includes a sheet former adapted to form a flat flexible sheet into a curved form and to feed the curved sheet into the open end of the tube member located in the bore hole.

19. The drilling apparatus of claim 18, wherein the forming apparatus includes a wide mouth inlet and tapers to a narrower round outlet to define a path for a flexible sheet and a feeding mechanism for feeding the flexible sheet through the inlet and the round outlet and into the tube member.

20. The drilling apparatus of any one of claims 16 to 19, including a store of a plurality of the flexible sheets and a picker adapted to pick the sheets one at a time.

21. The drilling apparatus of any one of claims 14 to 20, further including a shroud adapted to be substantially sealed with the longitudinal internal passage of the tube member for directing cuttings and/or bailings that emerge from the bore hole during drilling.

22. The drilling apparatus of claim 21, wherein the shroud includes an axial passageway for receiving the drilling string therethrough and an outlet opening that is oriented transversely to the axial passageway.

23. The drilling apparatus of claim 22, wherein the outlet opening is adapted to be coupled to a flexible conduit of a vacuum apparatus.

24. The drilling apparatus of any one of claims 21 to 23, wherein the shroud is mounted to the mast and an actuator is adapted to translate the shroud upwards and downwards in a linear range of motion.

25. The drilling apparatus of any one of claims 21 to 24, further including an outlet located next to or underneath the mobile platform for directing cuttings and/or bailings that emerge from the bore hole during drilling to a pile adjacent to or beneath the mobile platform.

26. The drilling apparatus of any one of claims 14 to 25, including a system for injecting a composition between the external surface of the tube member and the surrounding wall of the bore hole.

27. A method of drilling a bore hole including: coupling a tube member to a mast of a mobile drilling rig, the tube member including a longitudinal internal passage for receiving a drill string therethrough; boring a hole into a bench surface and lowering the tube member within the collar region of the bore hole, the tube member including an external surface for facing outwardly against a wall of the bore hole.

28. A method of providing a collar support apparatus into a bore hole, the method including: coupling a tube member to a mast of a mobile drilling rig, the tube member including a longitudinal internal passage for receiving a drill string therethrough; boring a hole into a bench surface and lowering the tube member within the collar region of the bore hole, the tube member including an external surface for facing outwardly against a wall of the bore hole; providing a support in the bore hole for stabilising the collar region of the bore hole; and removing the tube member from the bore hole.

29. The method of claim 28, wherein providing a support in the bore hole includes inserting a collar support apparatus comprised of a flexible sheet of material into the longitudinal internal passage of the tube member and wherein removing the tube member from the bore hole leaves behind the collar support apparatus within the bore hole.

30. The method of claim 29, including moving the mast relative to the tube member for accessing the longitudinal internal passage of the tube member.

31. The method of claim 30, wherein moving the mast relative to the tube member includes moving the mast between a position in which the tube member is aligned with an axis of the drill string and another position in which the tube member is offset from the axis of the drill string while the tube member and the mast remain coupled together.

32. The method of any one of claims 28 to 31 , wherein removing the tube member from the bore hole includes maneuvering the mast to raise the tube member out of the bore hole.

33. The method of any one of claims 28 to 32, wherein coupling the tube member to the mast includes horizontally translating the mast relative to the tube member.

34. The method of claim 28, wherein providing a support in the bore hole for stabilising the collar region of the bore hole includes injecting a composition between the external surface of the tube member and the surrounding wall of the bore hole.

35. The method of claim 34, wherein the injected composition cures or otherwise hardens or solidifies to become self-supporting or binds the loose rock fragments to form a composite collar support.

36. A sheet forming device adapted to form a flat flexible sheet into a curved form and to feed the curved sheet into a tube member located within the collar region of a bore hole, the device including: a forming apparatus adapted to form a flat flexible sheet into a curved form; and a feed mechanism for feeding the curved sheet into the open end of the tube member located within the collar region of a bore hole.

37. The device of claim 36, wherein the forming apparatus includes a wide mouth inlet and tapers to a narrower round outlet to define a path for the flexible sheet wherein the feeding mechanism feeds the flexible sheet through the inlet and the outlet of the forming apparatus and into the tube member.

38. The device of claim 36 or claim 37, including a plurality of the flexible sheets arranged in a stack from which the feed mechanism is configured to pick the sheets one at a time.

39. The device of any one of claims 36 to 38, wherein device is configured for attachment to a mast of a bore hole drilling apparatus.