Abstract: The present invention includes a rock bolt having a longitudinally expandable tube. The tube includes a longitudinally extending depression that defines a temporary enclosed longitudinal passageway. The rock bolt further includes a shielded distal end to prevent debris from entering the temporary enclosed longitudinal passageway. The distal end is shielded using a cover which may be a plug or a cap and may provide a rounded tip for the rock bolt. The plug may be spherical. The cap may be attached such that its proximal end abuts the distal end of the rock bolt, is inserted into the distal end of the rock bolt, or extends beyond the distal end and along the sidewall of the rock bolt. The present invention also includes a method of making such a rock bolt and a method of using such a rock bolt.

Abstract: A bail (20) for an expansion shell assembly which is formed from a continuous elongate metallic member shaped to have a yoke (24), at least two U-shaped legs (26,28,30) which extend from the yoke, and a biasing element (76) which projects from the yoke.

Abstract: A rock anchor (10) which includes a cable (12) with a hollow core, an expansion mechanism (20) at one end of the cable, a tube (14), which acts on a load washer (16), in which part of the cable is located, and a wedge (18) which locks the cable to the tube.

Abstract: A sleeve 10 for introduction of a pressurized fluid, which is attached to a rockbolt main body 1, comprises a cylindrical projecting part 11 of a large diameter and a bearing-plate-holding part 12 of a diameter smaller than an aperture of a bearing plate 6. The projecting part 11 and the bearing-plate-holding part 12 preferably has the same inner diameter. When the rockbolt main body 1 is embedded in a bedrock or ground, the bearing plate 6 locates on an edge of a rockbolt-setting hole of the bedrock or ground, and the bearing-plate-holding part 12 extends through the bearing plate 6 into the rockbolt-setting hole. Since the projecting part 11 and the bearing plate 6 are disposed on a sprayed concrete layer, a projection height of the rockbolt is remarkably decreased. Consequently, lining concrete 8 is applied onto the sprayed concrete layer with ease, and the bedrock or ground is reinforced with high reliability.

Abstract: A friction tube anchor has a tube (1) which can be expanded under the action of a pressurized medium and which is attached to a casing (6). The casing (6) is screwed into a section (13) of a casing-like sleeve (7) which is provided with a thread and is sealed by ring packing (11) relative to the inside of the section (13). The casing-like sleeve (7) has another section (14) which is provided with a thread and in which selectively either another expandable tube (1), or an adapter for feeding the pressurized medium for expanding the tube (1), or a fastening bolt, for example an eye bolt, can be screwed.

Abstract: A method and device for drilling, particularly percussion drilling or rotary percussion drilling a hole in soil or rock material and fixing an anchoring in the hole. To this end, a drilled hole is made by a drill bit mounted on a drill rod. The drill rod, on the rear side facing away from the drilling surface of the drill bit, is surrounded at a distance from the drill bit by an anchoring element whose outside dimension exceeds, at least in part, the circumference of the drilled hole made by the drill bit.

Abstract: An expansion shell assembly for mine roof bolts includes an expansion member threaded onto an associated mine roof bolt. A support device is annularly disposed around the associated roof bolt. An expansion shell is annularly disposed around the associated roof bolt between the expansion member and the support device. The expansion shell has a base ring for engaging the support device and fingers for engaging a peripheral edge of the tapered plug. The engagement between the base ring and the support device permits axial traverse movement of the support device relative to the expansion shell for tensioning the roof bolt.

Abstract: The invention relates to a rock anchor including an elongate, hydraulically inflatable anchor tube made of a ductile material and defining a closed leading end, a trailing end, and a tube cavity extending between the ends. The rock anchor of the invention includes an end cap on a trailing end of the tube, defining a feed aperture in communication with the tube cavity for pressure feeding a liquid substance into the tube cavity for inflating the tube. The end cap includes pressure indicator means configured for indicating when, as a result of pressure feeding of a liquid substance into the tube cavity, a predetermined installation pressure is reached in the tube cavity. The pressure indicator means typically includes a pressure indicator formation displaceable under pressure in the tube cavity, with such displacement being visible from the outside of the end cap.

Abstract: A device (5) for installing a pressure fluid expandable rock bolt (4) of the kind having a tubular expansion portion and a fitting portion, said device at a distal portion having chuck means for gripping the fitting portion and for establishing a sealed connection between a fluid source and the inlet, said device extending essentially in an axial direction. The device includes at a proximal portion a holder portion (11) that is adapted to be fitted to a drill string engagement element (27) of a rock drilling machine. The invention also concerns a method and a rig.

Abstract: A high-strength steel pipe rockbolt has an expansive rockbolt main body prepared by processing a high-strength steel sheet of 1.8-2.3 mm in thickness with a tensile strength of 490-640 N/mm2 and an elongation of 20% or more into a welded pipe and roll-forming the welded pipe into a shaped pipe having one or more concavities extending along an axial direction. Use of the high-strength steel sheet ensures sufficient strength of the shaped pipe regardless of a decrease in thickness. The thin welded pipe is also advantageous in resistance to cracking caused by accumulation of strains introduced during roll-forming, swaging both ends of the welded pipe and hydraulic expansion. Moreover, expansive deformation of the shaped pipe is initiated by injection of a pressurized fluid at a low pressure, so that the expansive deformation is completed in a short time period with an improved working efficiency.

Abstract: A roof stabilizer for use in securing surfaces in tunneling and mining is disclosed and claimed. The stabilizer has a tube with a slot and a ring attached to the bottom end of the tube. The ring can have indicia on a bottom surface of the ring or a side surface of the ring or both. The location of the indicia can provide better indication of the properties of the stabilizer to the installer. The indicia is easier to read than that of the background art both before and after installation. The location of the indicia can also provide easer and quicker visual inspection of already installed stabilizers to verify that the proper roof stabilizers were installed. The location of the indicia lessens the likelihood that corrosion will remove the indicia making it unidentifiable. The stabilizer disclosed and claimed also allows the use of grout or an adhesive in the interior of the tube which does not cover up or conceal the indicia on the ring as opposed to indicia in the background art stabilizers.

Abstract: After a rock anchor which encompasses the anchor bolt, has been inserted with an end sleeve beforehand into a bore hole, on the sleeve there is an adapter with liquid supply and drain. Via the holding pressure line a holding pressure is produced which fixes the adapter on the sleeve. Via the expansion line fluid flows into the anchor bolt and begins to fill it. The anchor bolt expands as a result of the pressure increase in the bore hole, so that its outer surface adjoins the bore hole wall and fixes the rock anchor in the bore hole. Via a gas supply connected to the adapter, a pressurized gas, before and/or after expanding the anchor bolt, can be introduced into the latter. The compressed gas is relieved after removing the adapter and routs the fluid located in the anchor bolt almost completely out of the anchor.

Abstract: An excavation apparatus having a mast, a sled slidably mounted thereon, a sled driving system for downcrowding and upcrowding the sled along the mast, and non-rotatable but extendable kelly sections that prevent slippage of the sled on the mast. An outer kelly section is attached to the sled, and an inner kelly section is extendable therefrom and retractable therein. A bushing maintains slidable alignment of the kelly sections on the mast. The inner kelly section is automatically powered into and out of the outer kelly section a distance proportional to the distance that the sled is downcrowded or upcrowded along the mast while preventing slippage. A rotary motor, attached to the sled, rotates a telescopic shaft housed within the kelly sections. A transmission secured to the lower end of the inner kelly section increases downhole torque. A boom connector downcrowds and upcrowds the mast for additional drilling depth capability.

Abstract: The present invention relates to a rock bolt comprising first and second ends, a shaft extending between the ends, and an anchoring device extending along a first part of the shaft adjacent the first end. The anchoring device comprises a mandrel, and at least one expansion element overlaying the mandrel. The expansion element is displaced radially outwardly on a predetermined relative movement between the mandrel and the expansion element. The expansion element is joined to a connector to form an anchor assembly. The anchor assembly is keyed to the mandrel. The anchor assembly comprises relative rotation actuator means active during rotation of the anchoring device. The invention further relates to an anchoring device per se.

Abstract: A self drilling rock bolt incorporating a shaft and an anchoring device. A first end of the bolt has a drill tip to penetrate rock and a second end is adapted to be connected to a drilling apparatus to allow rotation of, and thrust to, the bolt. A circulation passage is provided to allow fluid to be passed to the drill tip and in one form a central passage is formed in the shaft to form part of this circulation passage. The anchoring device is operative to retain the bolt when located in a drilled hole and comprises a mandrel having one or more inclined external surface mounted to, or integrally formed with, the shaft and at least one expansion element overlaying the mandrel. The expansion element(s) is displaced radially outwardly on a predetermined relative movement between the mandrel and the element.

Abstract: An expansion anchor assembly for a mine roof bolt having a tapered plug, expansion leaves, a bail and a removable holding ring configured to hold the expansion anchor assembly in an assembled position is disclosed. The tapered plug is configured to be threaded onto the mine roof bolt and defines plug channels to encourage symmetrical resin flow past the tapered plug. The bail defines a medial opening through which the mine roof bolt extends.

Abstract: A friction tube anchor has a tube (1) which can be expanded under the action of a pressurized medium and which is attached to a casing (6). The casing (6) is screwed into a section (13) of a casing-like sleeve (7) which is provided with a thread and is sealed by ring packing (11) relative to the inside of the section (13). The casing-like sleeve (7) has another section (14) which is provided with a thread and in which selectively either another expandable tube (1), or an adapter for feeding the pressurized medium for expanding the tube (1), or a fastening bolt, for example an eye bolt, can be screwed.

Abstract: A device (5) for installing a pressure fluid expandable rock bolt (4) of the kind having a tubular expansion portion and a fitting portion, said device at a distal portion having chuck means for gripping the fitting portion and for establishing a sealed connection between a fluid source and the inlet, said device extending essentially in an axial direction. The device includes at a proximal portion a holder portion (11) that is adapted to be fitted to a drill string engagement element (27) of a rock drilling machine. The invention also concerns a method and a rig.

Abstract: The invention relates to an anchor device, for stabilizing an excavation wall and to be inserted into a hole, bored in an excavation wall. Said anchor device comprises a rigid elongated rod which defines a distal end, to be inserted into the bored hole and a proximal end, opposed to the distal end, a support member, mounted on the rod in the vicinity of the proximal end thereof and provided for resting against an outer surface of the wall of rock and an anchor head, mounted on the rod and to be inserted into the hole, bored in the excavation wall. Said anchor head comprises a flexible expandable member, mounted on the rod, made of plastic and capable of radially expanding and stretching and an activating member, movably mounted on the rod, said activating member being capable of moving relative to the rigid rod and to the expandable member and capable of contacting the same in order to exert a pressure.

Abstract: An apparatus (100) for post-grouting a rock bolt (1) has an elongate sleeve (101) adapted to receive a rock bolt (1) with a first end (1a) thereof extending beyond the sleeve first end (101a) and a second end (1b) thereof extending beyond the sleeve second end (101b). An end fitting (102) is attached to the sleeve second end (101b) and has a central aperture (106, 107) for receiving the rock bolt (1). Grout passages (112) communicate the exterior of the end fitting (102) with the interior of the sleeve (101). A seal means (117) is displaceable between open and closed positions so as to seal the grout passages (112). The seal means (117) is biased towards the closed position at which the grout passages (112) are substantially sealed. Injection of grout into the end fitting (102) via the passages (112) deflects the seal means (117) to the open position enabling flow of grout through the passages (112) and into the sleeve (101).

Abstract: In a method and a device for installing, in a rock wall or roof, a self-drilling expandable rock bolt (2) having a drill bit portion (5), an expansion portion (9) and a connecting portion (10), in a rock breaking step, the self-drilling rock bolt (2) is provided with a rock breaking movement and flushing fluid for producing a bore hole, and in an expansion step, pressurized expansion fluid is introduced into the expansion portion (9) in order to expand it so as to be fixed to the inside of the bore hole. Expansion fluid is introduced by means of a swiveling device (6) so that the rock bolt (2) is free to move during the rock breaking step, and be tightened against the rock bolt (2) in the expansion step in such a way that a sealed channel for expansion fluid is established between an expansion fluid source and the expansion portion (9). The invention also concerns a self-drilling rock bolt.

Abstract: A lock bolt of a high strength steel pipe, wherein an expansion type lock bolt body is formed of a deformed pipe manufactured by using, as a raw material, a high tension steel plate having a tensile strength of 490 to 640 N/mm2, an elongation of 20% or more, and a plate thickness of 1.8 to 2.3 mm and having a single or a plurality of recessed parts extending in the axial direction of the deformed pipe. Since the high tension steel plate is used in the lock bolt, sufficient strength can be secured for the lock bolt though the steel plate is thin, and cracking due to stains introduced in a molding process, a both end shrinkage process, and a pressurizing/expanding process can be suppressed. Since an expansion start pressure when a pressurized fluid is press-fitted and inflated is also low, a time in which the expansion/deformation is completed can be shortened and workability can also be improved.

Abstract: A friction rock stabilizer includes an elongated metal tube having and interior and an exterior surface with a distal end and a proximal end. The distal end is tapered and a flange is positioned adjacent the proximal end. The tube further includes a slit that runs substantially the entire length thereof. The tube is constructed so as to be capable of being positioned within a bore formed in the wall of a mine. An internal sleeve is located adjacent the distal end of the tube. A tapered expander is also located within the interior of the tube adjacent the distal end and is actuatable from the proximal end of the tube after the point anchor is installed in a bore. The tapered expander expands the distal end of the tube to firmly anchor the stabilizer in the bore.

Abstract: A friction rock stabilizer includes an elongated metal tube having and interior and an exterior surface with a distal end and a proximal end. The distal end is tapered and a flange is positioned adjacent the proximal end. The tube further includes a slit that runs substantially the entire length thereof. The tube is constructed so as to be capable of being positioned within a bore formed in the wall of a mine. An internal sleeve is located adjacent the distal end of the tube. A tapered expander is also located within the interior of the tube adjacent the distal end and is actuatable from the proximal end of the tube after the point anchor is installed in a bore. The tapered expander expands the distal end of the tube to firmly anchor the stabilizer in the bore.

Abstract: The present invention is related to a method for manual installation of rock bolts expandable by means of a pressure media comprising manual coupling of a pressure source to a rock bolt to be expanded. The method comprises the steps of an operator starting a sequence whereby the rock bolt is pressurized to a predetermined pressure, and it being ensured that the predetermined pressure is kept for a predetermined period of time. The present invention is also related to such a control system, and an apparatus comprising such a control system.

Abstract: Method and device for rock bolting, wherein a tubular bolt (2) with closed cross-section is inserted and expanded for anchoring inside a bore hole (12), wherein the tubular bolt is expanded to contact in the inner portion of the bore hole, a tension element (3, 7, 8, 9) which is arranged in the outer portion of the bore hole with an inner part (7) attached to the tubular bolt (2) is pre-stressed and a settable medium is injected into the outer portion of the bore hole (14) between (27) the tension element and the wall of the bore hole and is allowed to set.

Abstract: The present invention is related to a rock bolt (7), expandable by means of a pressure media, for insertion into a borehole. The expandable bolt (7) comprises a connection unit (8) with means (11) for detachable interaction with an expansion means (10) for expansion of the rock bolt (7), as well as with a suspension element (16). The connection unit is designed with such external dimensions so that it may be inserted into the bore-hole. The invention also relates to such a rock bolting system.

Abstract: A method of joining expandable tubulars includes joining the tubulars by forge welding and flushing a reducing flushing gas around the heated tubular ends during at least part of the forge welding operation such that oxides are removed from the forge welded tubular ends and the amount of irregularities between the forge welded tubular ends is limited.

Abstract: A method and a device for the drilling, in particular the percussive or percussive rotary drilling of a hole in earth or rock and for securing an anchorage in the hole. A bore hole is created by a drill bit mounted on a drill pipe and a sliding sleeve that surrounds the drill pipe at a distance is simultaneously introduced. A sliding sleeve configured with a longitudinal slit is introduced at least partially and rests substantially against the bore hole during the drilling, whereby a reliable anchorage can be achieved with a simple construction by the sliding sleeve with a longitudinal slit.

Abstract: In a method and device for drilling, in particular impact drilling or rotary percussion drilling, a hole in soil or rock material and forming an anchorage in the hole, wherein a bore hole is formed by the introduction of a drill bit, it is provided that the drill rod assembly of the drilling device includes at least one expandable element having at least one hollow space extending substantially in the longitudinal direction of the bore for introducing a fluid under pressure to at least partially widen the outer periphery of the expandable element, and/or the drill rod assembly is connected with at least one expandable element each including at least one hollow space substantially extending in the longitudinal direction of the bore for introducing a fluid under pressure to widen the outer periphery, thus ensuring a safe anchorage by the expansion of the expandable elements both over the periphery and over the length of the device at a simplified overall construction.

Abstract: A system for mine roof reinforcement includes a bearing plate and a tubular member with an inner surface, an outer surface, first and second free ends, and an enlarged portion disposed proximate one of the free ends. The system also includes a projectile and an insertion member for being received in the tubular member. In addition, a method for inserting a bolt in rock includes: forming a borehole in rock; placing a bearing plate with an opening therein against the rock so that the opening is aligned with the borehole; disposing a tubular member in the borehole and opening so that an enlarged end of the tubular member abuts the plate; and mechanically expanding the tubular member so that an outer wall thereof frictionally engages the rock.

Abstract: An expansion wedge anchor (80) for insertion in a hole (H) delimited by a wall comprises an expander member (32) and an expansion number (34), the expander member being provided at a leading end of the expander member, the expander member comprising a flaring end (40), the expansion member being expandable at a trailing end (48) thereof and being adapted to engage the wall of the hole when the expander member is positioned in the hole, wherein upon longitudinal withdrawal of the expander member from the hole, the expander member displaces longitudinally relative to the expansion member with the flaring end thereof gradually causing the trailing end of the expansion member to expand, whereby a trailing edge of the expansion member engages the wall of the hole. The trailing end is adapted, when expanded by the flaring member, to extend at an angle with respect to a longitudinal axis of said expander member.

Abstract: A mechanical anchor includes an anchor unit that is divided into a plurality of divided anchor units which are movably connected to a tension rod to be moved in lateral directions. The anchor unit is opened or closed by the movement of the divided anchor units, and the anchor unit forms a cylindrical shape when the divided anchor units are closed. A driving member for opening or closing the anchor unit is mounted on an inner side of the anchor unit in such manner that the driving member is extended in a longitudinal direction of the anchor unit. The driving member and each of the divided anchor units are connected with each other so that the driving force of the driving member is equally applied on each of the divided anchor units.

Abstract: This invention relates to a rock bolt and to its method of use. There is disclosed a rock bolt comprising an elongated bar and an elongated drformable member, with means to reduce the distance between the respective ends of the deformable member so as to deform at least part of the member away from the bar. The means to reduce the distance between the respective ends of the deformable member may be located at the distal end of the rock bolt or the proximal end thereof. Though the term “rock bolt” is used, the bolt may be used as a ground anchor, or in other suitable applications, in which it is located in a hole drilled into earth as well as or instead of rock.

Abstract: An expansion shell assembly for mine roof bolts includes an expansion member threaded onto an associated mine roof bolt. A support device is annularly disposed around the associated roof bolt. An expansion shell is annularly disposed around the associated roof bolt between the expansion member and the support device. The expansion shell has a base ring for engaging the support device and fingers for engaging a peripheral edge of the tapered plug. The engagement between the base ring and the support device permits axial traverse movement of the support device relative to the expansion shell for tensioning the roof bolt.

Abstract: A mortar composition, curable by frontal polymerization after heat initiation, is described, wherein are contained a) at least one polymerizable monomer and/or at least one curable resin, b) at least one polymerization initiator, which can be activated and/or released thermally at a temperature above 30° C., for the polymerizable monomers and/or curing accelerator for the curable resin and c) optionally at least one filler, the nature and amount of polymerizable monomer or curable resin and polymerization initiator or curing accelerator being selected so that a polymerization front velocity of at least 10 cm/min results after the polymerization is initiated, as well as a method for fastening tie bars, reinforcing steel or the like in solid substrates.

Abstract: An expansion anchor to be set in a bore of a constructional component and including an anchor member (1) having, at its end facing in a setting direction, an expansion region (5), a guide region (6) remote from the setting direction end of the anchor member (1), and a transition region (8) located between the expansion (5) and guide (6) regions and having at least one opening (10) and at least one salient tab (12) provided in a region of the opening; and a cone (3) for expanding the expansion region (5) of the anchor member (1)

Abstract: A package of rock stabilizer sets and a method for arranging the sets where six sets are provided and each set includes an elongated tube and a bearing plate. Each tube has a tapered end, an end with a flange, and a slit running the length of the tube. Each bearing plate has a flat base and a central domed section having a central aperture therethrough. In a first embodiment, the tubes of four of the sets are arranged in a first or bottom layer so that the flanged and tapered ends of the tubes are aligned alternatively and the slits face downwardly. Next, the plates of three of the sets are placed along the length of the four tubes so that the domed sections face upwardly, thereby forming a second layer. A third layer is formed by placing the three remaining plates on top of the first three plates, respectively, so that the domed sections of the second layer nest within the respective domed sections of the third layer.