TECHNICAL FIELD

[0001] The present invention relates generally to the field of drilling and mining and particularly to a mechanical packer for use in underground mining to seal a pre-drilled hole.

BACKGROUND ART

[0002] There are currently mechanical packers available that require manual installation into a hole formed in a surface. A mechanical hand set packer is a reusable item for low pressure grouting holes near the surface (as the setting depth is approximately lm). The packer is set and held in the hole by the force of the packing segment against the hole wall only and that pressure is applied by screwing the handle up the thread to expand the packing segment.

[0003] This packer relies on the operator to ensure adequate tightening of the packer in the hole. The packer must be rock bolted to the face of the hole in all situations before grouting can occur. A grout pump is connected by either a 3/4", 1" or 2" BSP socket depending on packer size. These mechanical hand set packers are limited to an insertion depth of 3 to 4 meters.

[0004] The manual packer includes a reusable applicator including an elongate external threaded arm over which a downhole plug is located. The downhole plug is then inserted into the hole as required and the threaded arm rotated to expand the plug. The assembly is then grouted in place and the applicator is loosened and removed from the hole for reuse.

[0005] These packers are limited in depth to which the packer can be installed. Further, the manner in which the packer is installed requires that personnel are placed in a dangerous position during installation due to the close proximity required.

[0006] It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

SUMMARY OF INVENTION

[0007] The present invention is directed to a packing plug, which may at least partially overcome at least one of the abovementioned disadvantages or provide the consumer with a useful or commercial choice.

[0008] With the foregoing in view, the present invention in one form, resides broadly in a packing plug including an elongate, externally threaded, hollow rod and at least one plug assembly including a first collar located about the rod and fixed relative thereto, a deformable sleeve located about the rod against the first collar and a second collar mounted about the rod adjacent the deformable sleeve such that movement of the second collar relative to the rod in a first direction moves the second collar closer to the first collar deforming the deformable sleeve therebetween causing radial enlargement of the deformable sleeve.

[0009] In an alternate form, the present invention resides in a packing plug including an elongate, externally threaded, hollow rod and at least one plug assembly including a stop located about the rod and fixed relative thereto, a deformable sleeve located about the rod against the stop and a movable compression structure mounted about the rod adjacent the deformable sleeve such that movement of the compression structure relative to the rod in a first direction moves the compression structure closer to the stop deforming the deformable sleeve therebetween causing radial enlargement of the deformable sleeve.

[0010] Typically, devices such as the packing plug of the present invention are used to seal a hole in a surface, typically a drill hole or similar which is formed for the purposes of the rock bolting or water probe drilling.

[0011] The packing plug of the invention can be -used to simply seal an existing hole alternatively, can be used to seal a hole into which a stabilization bolt or rock bolt is already inserted or into which it will be inserted.

[0012] It is particularly preferred that the packing plug of the present invention is used in situations where a self drilling anchor is used, particularly where the creation of the hole into which the self drilling anchor is inserted, allows fluid, particularly water into the hole. In these situations, the hole must be sealed in order to prevent further inflow of water.

[0013] Self drilling anchors have three main areas of application including the slope stabilization, foundations with micro piles and tunnelling. In the slope stabilization application, a self-drilling anchor is typically used to stabilize unstable rock or soil formations. Self drilling anchor micropiles can be defined as drilled piles, composed of injected grout with the self drilling anchor rod as steel reinforcement. In the tunnelling application, self-drilling anchors are used to reinforce the tunnel circumference and provide advanced roof support for tunnel excavation in overburdened and soft fractured rock conditions.

[0014] The packing plug of the present invention is therefore typically used to prevent water or liquid running out of the hole formed in the surface and/or to seal the hole to allow grouting to be more effective.

[0015] The packing plug of the present invention typically includes an elongate, externally threaded, hollow rod. This hollow rod is typically at least partially threaded but preferably completely threaded over its length. The hollow rod may be threaded only in the approximate position of the at least one plug assembly in order to minimize the amount of threading that must be provided on the rod. The rod will typically function as an anchor rod and will remain in situ when the packing plug is activated.

[0016] There may be more than one rod section or length coupled together depending upon the length of the hole and therefore, the length of the rod required. In this configuration, extension couplings are typically provided. Any type of extension coupling to couple one or more rod sections together can be used. Typically, the rod sections will be available in one or more standard lengths and two or more lengths are typically attachable to one another to form a longer rod.

[0017] The rod of the present invention may or may not include a drill bit in order to form a hole. Preferably, the packing plug including the rod will not be provided with a drill bit and instead, a non-return valve will be provided at a forward end of the rod.

[0018] The helix of a thread can twist in two possible directions, which is known as handedness. Most threads are oriented so that the threaded item, when seen from a point of view on the axis through the centre of the helix, moves away from the viewer when it is turned in a clockwise direction, and moves towards the viewer when it is turned counter clockwise. This is known as a right-handed (RH) thread, because it follows the right hand grip rule. Threads oriented in the opposite direction are known as left-handed (LH). Typically, the thread on the hollow rod will be a left-hand thread to match teh drilling equipment which is preferably used for installation.

[0019] Although the rod of the present invention can be formed from any material, preferably, the rod will be formed from cold rolled steel or similar as this material is preferred for hardness and strength but any material can be used depending upon the application.

[0020] The rod of the present invention is hollow. The rod is typically hollow over its length and normally, a bore of constant dimension is provided through the rod. The dimension of the bore can depend on a number of parameters but the size of the bore compared to the size of the rod will affect wall thickness of the rod for a given outer diameter. [0021] Typically, the bore can be provided for flushing or allowing fluid to escape outwardly through the rod but this will typically be prevented by the preferred non-return valve provided at a forward end of the rod. In particular, the bore is adapted to allow insertion of material into the hole through the rod. This will typically be the case where the rod is provided have been fixed in place using grout or similar.

[0022] The packing plug of the present invention includes at least one plug assembly. More than one plug assembly may be provided. If more than one plug assembly is provided, typically, the plug assemblies will be spaced over the length of the rod. Providing more than one plug assembly may assist with creating a seal between the plug assembly and the hole particularly if high pressures are encountered.

[0023] The packing plug of the present inventio includes a first collar or stop located about the rod and fixed relative thereto. The first collar preferably acts as a stop or an abutment surface in order to prevent lateral movement or translation of the deformable sleeve along the rod. The first collar or stop is not provided to prevent deformation, but is instead provided as a stop against which the deformable sleeve can be deformed.

[0024] The first collar does not have to, but preferably extends about the circumference of the rod continuously. Typically, the first collar is annular in configuration and in a particularly preferred embodiment, is a washer or similar having a substantially planar annular shape.

[0025] The outer diameter of the first collar is typically approximately as large as the outer diameter of the deformable sleeve, but preferably slightly smaller so that it does not foul on teh periphery of the hole when inserted. The preferred annular shape of the first collar provides an abutment surface on one side for the deformable sleeve and an abutment surface on the opposite side of the first collar in order to abut a location fixing device such as a nut or similar. The provision of an internally threaded nut allows movement of the nut and first collar along the threaded rod until the first collar is positioned as required. Typically, the nut is fixed in position relative to the threaded rod.

[0026] The first collar may or may not be fixed to the preferred nut. However, the nut is preferably provided for strength purposes. The nut is typically fixed to the rod so that it does not unwind during installation or over time work loose.

[0027] Any method of fixing may be used but given that most of the components of the packing plant are manufactured from metal, welding is a preferred method. As mentioned above, the nuts can be welded to the rod and the preferred first collar then welded to the nut. In this configuration, the first, and the nut will co-rotate with the elongate rod. It is also preferred that the first collar is fixed to the nut circumferentially so that water cannot work through the small gap in the abutment of the first collar and the nut.

[0028] Typically, the first collar extends equally from the rod in all directions. There may be a variety of standard sizes of first collar depending upon the size of the hole into which the packing plug of the preferred embodiment is inserted or used.

[0029] The packing plug of the present invention includes a deformable sleeve located about the rod against the first collar. It is not essential that the deformable sleeve abut the first collar at all times, but in use, the deformable sleeve will abut the first collar at least when the second collar is moved toward the first collar.

[0030] Generally, the deformable sleeve is annular in cross-sectional shape and elongate having an external appearance similar to a cylinder with a longitudinal bore. More than one deformable sleeve may be used in each plug assembly if required. In this configuration, typically the ends of the deformable sleeves abut one another such that compression applied to one of the sleeve is transmitted to the other sleeve(s).

[0031] Preferably, each deformable sleeve may be formed of rubber but similar materials or substitutes such as plastics or polymer materials can be used. In some embodiments, the deformable sleeve may be formed from a combination of material in order to provide particular characteristics.

[0032] The deformable sleeve can be of any length. Typically however though the length of the sleeve will affect the amount of radial enlargement that can be achieved.

[0033] The deformable sleeve preferably includes a longitudinal bore and this bore preferably fits closely over the rod. In particular, the inner diameter of the longitudinal bore is similar to the external diameter of the rod.

[0034] The deformable sleeve preferably has a pair of substantially planar annular end faces. One of the end faces will typically about the first collar or stop and the second end face will abut either the second collar, compression structure or an adjacent deformable sleeve. Preferably, the end faces abut respective surfaces directly.

[0035] The packing plug includes a second collar mounted about the rod adjacent the deformable sleeve such that movement of the second collar relative to the rod in a first direction moves the second collar closer to the first collar deforming the deformable sleeve therebetween causing radial enlargement of the deformable sleeve.

[0036] Preferably, the second collar is similar and typically the same as the first collar. The second collar also preferably has a nut associated therewith in order to move the second collar against the resilient force provided by the deformable sleeve in order to deform the deformable sleeve.

[0037] Preferably, the second nut is not attached to the second collar, nor is it attached to the rod. Rotation of the second nut relative to the rod [or the rod relative to the second nut] in a first direction, moves the second nut toward the first collar. The second nut is therefore appropriately mounted to the rod and also has a thread of the correct handedness to achieve this.

[0038] In a particularly preferred embodiment, a socket assembly is provided in order to rotate the second nut. Typically, the socket is elongate and at least partially hollow. Generally, the socket assembly has a tubular forward end which is adapted to receive the elongate rod allowing a forward end of the socket assembly which is provided with engagement means in order to engage the nut, to engage the nut. The second engagement means is provided at the opposite ends of the socket assembly in order to engage a rotation mechanism allowing rotation of the socket assembly and thereby, drive rotation of the nut. Typically, the rotation mechanism used will be a rotation mechanism which is also used for drilling the hole in order to minimize equipment, particularly in an underground mine scenario. The socket assembly is therefore typically inserted into the hole coaxially about the hollow rod such that the engagement means at the forward end engages the nut. Again, more than one length socket assembly may be provided depending upon the length of the hole.

[0039] The first engagement means on the socket assembly will typically match or correspond with the second nut.

[0040] The packing plug of the present invention may be provided with a non-return valve at a forward end there of in order to substantially prevent fluid, particularly water flowing back through the hollow rod. Preferably, the non-return valve assembly will be provided as an additional fitting which engages with a forward end of the threaded rod. In particular, the nonreturn valve will have a valve body which is typically generally cylindrical and which has an at least partially threaded portion to engage with the end of the threaded rod. One or more openings will typically be provided in the valve body. These one or more openings typically extend at an angle to the bore of the hollow rod in order to allow for grout injection through the hollow rod once the packing plug is set.

[0041] A stop device will typically be provided in association with the at least partially threaded portion of the valve body in order to prevent over insertion of the rod into the valve body.

[0042] Typically, a valve member is located within the valve body. A forward end of the valve body is typically at least partially closed in order to prevent the valve member being displaced out of the forward end of the valve body. In a particularly preferred form, a

substantially spherical valve member is provided.

[0043] The forward end of the hollow rod is typically machined in order to provide a valve seat which corresponds in shape to at least a portion of the valve member. In practice, the fluid from the forward end will apply a dynamic force against the valve member which will force the valve member into sealing engagement with the valve seat at the forward end of the hollow rod. Conversely, any fluid or similar forced through the hollow rod from the rear end will displace the valve member from the valve seat allowing the fluid or similar to flow into the valve body and preferably out through the one or more openings. This is typically the mechanism which is used once the packing plug is set and a user wants to inject grout in order to fix the packing plug in position permanently. The grout may be cementitious or may be a settable or curable material. Other materials may be injected through the packing plug if desired such as dye for example.

[0044] A grout injection nozzle may be provided for this purpose. Typically, the grout injection nozzle will include a nozzle body which is capable of engagement with the rear end of the hollow rod used for the packing plug. Normally, a portion of the nozzle body will be threaded in order to engage the hollow rod directly. One or more sealing members may be used to improve integrity of the seal between the rod and the nozzle body.

[0045] Preferably, the nozzle body also includes an engagement assembly in order to engage a grouting conduit in order to supply grout to the injection nozzle. This engagement assembly is typically a simple as providing a threaded portion but more complex engagement assemblies can be provided.

[0046] Preferably, a restraint lug may be attached directly to an outer surface of the injection nozzle body. Typically, the restraint lug is permanently attached to the nozzle body. The restraint lug will preferably allow movement of the nozzle body using an attachment dolly or tool in order to attach the nozzle body to the hollow rod. In one particularly preferred form, the restraint lug is substantially U-shaped the free ends of each of the arms of the restraint lug permanently attached to the nozzle body. The bore is provided through the nozzle body which communicates with the bore of the hollow rod.

[0047] The attachment dolly or tool used to attach the grout injection nozzle is typically similar in configuration to the socket assembly. In particular, the attachment dolly or tool is typically elongate and substantially hollow with an engagement means at a rear end thereof to engage with a locating mechanism in order to control movement of the attachment dolly and therefore the grout injection nozzle. A forward end of the attachment dolly typically corresponds in shape at least somewhat with an external portion of the injection nozzle. According to a particularly preferred form, a forward end of the attachment dolly may have a slot in order to receive the restraint lug of the injection nozzle and therefore allow rotation of the injection nozzle to attach the injection nozzle to the threaded rod.

[0048] In yet another form, the present invention resides in a,method for sealing a drill hole or crack in a wall, the method including insertion of a packing plug within the hole, the packing plug including an elongate, externally threaded, hollow rod and a plug assembly including a stop located about the rod and fixed relative thereto, a deformable sleeve located about the rod against the stop and a movable compression structure mounted about the rod adjacent the deformable sleeve, and deforming the deformable sleeve therebetween causing radial enlargement of the deformable sleeve.

[0049] Typically, the step of deforming the deformable sleeve is accomplished by rotating the rod or the compression structure relative to the rod in a first direction to move the compression structure closer to the stop.

[0050] Any of the features described herein can be combined in any combination with any one or more of the other features described herein within the scope of the invention.

[0051] The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge.

BRIEF DESCRIPTION OF DRAWINGS

[0052] Various embodiment ^' s of the invention will be described with reference to the following drawings, in which:

[0053] Figure 1 is a sectional schematic view of a packing plug according to a preferred embodiment of the present invention. This embodiment is used in a high pressure application.

[0054] Figure 2 is a sectional schematic view of a packing plug according to a preferred embodiment of the present invention installed. This application of the plug is as a "cable" bolt for areas that require low pressure grout injection. This diagram is slightly different from the high pressure arrangement in Figure 1 because it has a filler tube incorporated into the centre shaft that exits on the inner side of the plug in the hole

[0055] Figure 3 is a sectional schematic view of a non-return or check valve according to a preferred embodiment of the present invention.

[0056] Figure 4 is a sectional schematic view of a grout injection nozzle according to a preferred embodiment of the present invention.

[0057] Figure 4A is an end view of the grout injection nozzle illustrated in Figure 4.

[0058] Figure 5 is a sectional schematic view of a packing plug installation dolly according to a preferred embodiment of the present invention.

[0059] Figure 5 A is an end view of the packing plug installation dolly illustrated in Figure 5.

[0060] Figure 6 is a sectional schematic view of a grout injection nozzle installation dolly according to a preferred embodiment of the present invention.

[0061] Figure 6A is an end view of the grout injection nozzle installation dolly illustrated in Figure 6.

[0062] Figure 7 is a detailed image of a plug assembly according to a preferred embodiment of the present invention.

[0063] Figure 8 is a view from above of a pair of packing plugs of different sizes according to a preferred embodiment of the present invention with non-return valves fitted to each.

[0064] Figure 9 is a sectional schematic view of a grout injection nozzle and installation dolly according to a preferred embodiment of the present invention.

[0065] Figure 10 is an end view of a pair of packing plugs of different sizes from the forward end as illustrated in Figure 8.

[0066] Figure 11 is an end view of one of the packing plugs illustrated in Figure 10 from the insertion end.

DESCRIPTION OF EMBODIMENTS

[0067] According to a particularly preferred embodiment of the present invention, a packing plant and method of use is provided.

[0068] The packing plug 10 illustrated in the accompanying Figures, particularly Figure 1 , includes an elongate, externally threaded, hollow rod 11 and a plug assembly 12 including a first collar 13 located about the rod 11 and fixed relative thereto, a deformable sleeve 14 located about the rod 11 against the first collar 13 and a second collar 15 mounted about the rod 11 adjacent the deformable sleeve 14 such that movement of the second collar 15 relative to the rod 11 in a first direction moves the second collar 15 closer to the first collar 13 deforming the deformable sleeve 14 therebetween causing radial enlargement of the deformable sleeve 14.

[0069] Typically, devices such as these are used to seal a hole in a surface, typically a drill hole or similar which is formed for the purposes of the rock bolting. A preferred form is illustrated in Figure 2.

[0070] The packing plug of the present invention is therefore typically used to prevent water or liquid running out of the hole formed in the surface and/or to seal the hole to allow grouting and/or stabilisation to be more effective.

[0071] The packing plug 10 illustrated includes an elongate, externally threaded, hollow rod 11 completely threaded over its length. The rod 11 also functions as an anchor rod and remains in situ when the packing plug is activated.

[0072] As illustrated in Figure 2, there can be more than one rod section 16 coupled together depending upon the length of the hole and therefore, the length of the rod required. In this configuration, extension couplings 17 are provided.

[0073] The thread on the hollow rod 11 of the illustrated embodiment is a left-hand thread.

[0074] A bore 18 of constant dimension is provided through the rod 11. The dimension of the bore 18 can depend on a number of parameters but the size of the bore 18 compared to the size of the rod 11 will affect wall thickness of the rod for a given outer diameter.

[0075] The bore 18 can be provided for flushing or allowing fluid to escape outwardly through the rod 11 but this will typically be prevented by a non-return valve 19 provided at a forward end of the rod 1 1 as illustrated in Figures 9 and 10. In particular, the bore 18 is adapted to allow insertion of material into the hole through the rod 11. This will typically be the case where the rod 11 is provided to be fixed in place using grout or similar.

[0076] The packing plug illustrated includes a single plug assembly 12, although generally, the packing plug assembly will be provided in a dimension to suit the dimension of the hole to be plugged. The packing plug assembly of the illustrated embodiment includes a first collar 13 located about the rod 11 and fixed relative thereto to act as a stop or an abutment surface in order to prevent lateral movement or translation of the deformable sleeve 14 along the rod 11. In the preferred embodiment, the first collar is a washer having a substantially planar, yet annular shape.

[0077] The outer diameter of the first collar 13 illustrated is approximately as large as the outer diameter of the deformable sleeve 14. The first collar 13 provides an abutment surface on one side for the deformable sleeve 14 and an abutment surface on the opposite side of the first collar 13 in order to abut a first nut 20 to fix the position of the first collar 13 on the rod 11. The provision of an internally threaded first nut 20 allows movement of the first nut 20 and first collar 13 along the threaded rod 11 until the first collar 13 is positioned as required.

[0078] The illustrated embodiment has the first nut 20 is been fixed in position relative to the threaded rod. Further, the first collar 13 is fixed to the first nut 20. Welding beads 21 are used in the preferred embodiment for both.

[0079] The packing plug assembly 12 also includes a deformable sleeve 4 located about the rod 11 against the first collar 13.

[0080] As illustrated, the deformable sleeve 14 is annular in cross-sectional shape and elongate having an external appearance similar to a cylinder with a longitudinal bore. More than one deformable sleeve 14 may be used in each plug assembly if required as illustrated in Figure 7 in particular with the ends of the deformable sleeves abutting one another such that compression applied to one of the sleeve is transmitted to the other sleeve(s).

[0081] Each deformable sleeve of the illustrated embodiments is formed of rubber but similar materials or substitutes such as plastics or polymer materials can be used.

[0082] The deformable sleeve 14 has a pair of substantially planar annular end faces, one of the end faces abutting the first collar 13 and the second end face abutting either the second collar 15, or an adjacent deformable sleeve such as in Figure 7. [0083] The packing plug of the present invention includes a second collar 15 mounted about the rod 11 adjacent the deformable sleeve 14 such that movement of the second collar 15 relative to the rod 11 in a first direction moves the second collar 15 closer to the first collar 13 deforming the deformable sleeve 14 therebetween causing radial enlargement of the deformable sleeve 14.

[0084] In the illustrated embodiment, the second collar 15 is a washer of the same size and configuration as the first collar 13. The second collar also has a nut 22 associated therewith in order to move the second collar 15 against the resilient force provided by the deformable sleeve 14 in order to forcibly deform the deformable sleeve 14 to cause the radial enlargement.

[0085] The second nut 22 is not attached to the second collar 15, nor is it attached to the rod 11. Rotation of the second nut 22 relative to the rod 11 in a first direction moves the second nut 22 toward the first collar 13. The second nut 22 is therefore appropriately mounted to the rod 11 and also has a thread of the correct hand to achieve this.

[0086] A packing plug installation dolly 23 with a socket assembly 24, a preferred form of which is illustrated in Figures 5 and 5A, is provided in order to rotate the second nut 22.

Typically, the dolly is elongate and hollow. Generally, the elongate body of the dolly is adapted to receive the elongate rod 11 allowing the socket assembly 24 at the forward end to engage the nut 22. An engagement thread 25 is provided at the opposite end of the dolly body in order to engage a rotation mechanism allowing rotation of the socket assembly 24 and thereby, drive rotation of the nut 22. Typically, the rotation mechanism used will be a rotation mechanism which is also used for drilling the hole in order to minimize equipment, particularly in an underground mine scenario. The dolly is inserted into the hole coaxially about the hollow rod 11 such that the socket assembly 24 at the forward end engages the nut 22.

[0087] The packing plug of embodiments illustrated in Figures 8 and 10 are provided with a non-return valve 19 at a forward end thereof in order to substantially prevent fluid, particularly water flowing back through the hollow rod 11. The non-return valve 19 is provided as an additional fitting which engages with a forward end of the threaded rod 11.

[0088] A preferred form of the non-return valve illustrated in Figure 3 has a valve body 26 which is generally cylindrical and which has a partially threaded portion to engage with the end of the threaded rod 11. Lateral openings 27 are provided in the valve body extending at an angle to the bore 28 of the hollow rod 11 in order to allow for grout injection through the hollow rod 11 once the packing plug is set.

[0089] A circumferential stop rib 29 is provided in association with the threaded portion of the valve body 26 in order to prevent over insertion of the rod 1 1 into the valve body 16.

[0090] A substantially spherical valve member 30 is located within the valve body 26. A forward end 48 of the valve body 26 is typically at least partially closed by a valve stop 31 in order to prevent the valve member 30 being displaced out of the forward end of the valve body 26.

[0091] The forward end of the hollow rod 11 is typically machined in order to provide a valve seat 32 which corresponds in shape to at least a portion of the valve member 30. In practice, any fluid in the hole trying to enter the rod 11 through the forward end will apply a dynamic force against the valve member 30 which forces the valve member 30 into sealing engagement with the valve seat 32 at the forward end of the hollow rod 11. Conversely, any fluid or similar forced through the hollow rod 11 from the rear end will displace the valve member 30 from the valve seat 32 allowing the fluid or similar to flow through the bore 28 of the rod 11, into the valve body 26 and out through the one or more openings 27. This is typically the mechanism which is used once the packing plug is set and a user wants to inject grout in order to fix the packing plug in position permanently.

[0092] A grout injection nozzle 33, one example of which is illustrated in Figures 4 and 4A may be provided for this purpose. As illustrated, the grout injection nozzle 33 includes a nozzle body 34 which is capable of engagement with the rear end of the hollow rod 11 used for the packing plug. Normally, a portion of the nozzle body 34 is threaded in order to engage the hollow rod 11 directly. One or more sealing members 35 may be used to improve integrity of the seal between the rod and the nozzle body. The body can be formed from two parts connected together, preferably welded 36.

[0093] The nozzle body 34 also includes a thread engagement 37 in order to engage a grouting conduit (not shown) in order to supply grout to the injection nozzle 33.

[0094] A restraint lug 38 is attached directly to an outer surface of the injection nozzle body 34 by welding 39. The restraint lug 38 allows movement and/or positioning of the nozzle body 34 using an attachment dolly (one form of which is illustrated in Figures 6 and 6A) in order to attach the nozzle body 34. to the hollow rod 11, particularly when the rod has already been inserted into the hole. In the illustrated form, the restraint lug 38 is substantially U-shaped with the free ends of each of the arms of the restraint lug 38 permanently attached to the nozzle body. - A bore is provided through the nozzle body 34 which communicates with the bore 38 of the hollow rod 11. [0095] The preferred form of grout nozzle attachment dolly 40 illustrated in Figures 6 and 6 A used to attach the grout injection nozzle 33 is typically similar in configuration to the packing plug installation dolly 23. In particular, the grout nozzle attachment dolly 40 is elongate and substantially hollow with a thread engagement 41 at a rear end thereof to engage with a locating mechanism in order to control movement of the attachment dolly 40 and therefore the grout injection nozzle 33. A forward end of the attachment dolly 40 corresponds in shape at least somewhat with an external portion of the injection nozzle 33. According to the preferred form illustrated, a forward end of the attachment dolly 40 has a slot 42 in order to receive the nozzle body 34 and restraint lug 38 of the injection nozzle 33 and therefore allow rotation of the injection nozzle 33 to attach the injection nozzle 33 to the threaded rod 11.

[0096] Alternatively, grout injection can be achieved using a configuration as illustrated in Figure 2, In that configuration, a central filler tube 43 is provided that extends coaxially through the rod 11. The filler tube 43 is maintained centrally by a cap 45 and communicates with a lateral opening 46 in the rod 11 to allow the grout to escape into the environs of the hole 47.

[0097] In use, the packing plug 10 is inserted into a hole 47, and then deforming the deformable sleeve causing radial enlargement of the deformable sleeve by rotation of the nut 22 which moves the second collar 15 towards the first collar 13.

[0098] In the present specification and claims (if any), the word 'comprising' and its derivatives including 'comprises' and 'comprise' include each of the stated integers but does not exclude the inclusion of one or more further integers.

[0099] Reference throughout this specification to One embodiment' or 'an embodiment' means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases 'in one embodiment' or 'in an embodiment' in various places throughout this specification are not necessarily all referring to the same embodiment.

Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

[00100] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art.