WO2009110894A1 - Tensionable spiral bolt with resin nut and related method - Google Patents
Tensionable spiral bolt with resin nut and related method Download PDFInfo
- Publication number
- WO2009110894A1 WO2009110894A1 PCT/US2008/055908 US2008055908W WO2009110894A1 WO 2009110894 A1 WO2009110894 A1 WO 2009110894A1 US 2008055908 W US2008055908 W US 2008055908W WO 2009110894 A1 WO2009110894 A1 WO 2009110894A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- bolt
- borehole
- spiral
- spiral shaft
- shaft portion
- Prior art date
Links
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D21/00—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
- E21D21/008—Anchoring or tensioning means
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D21/00—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
- E21D21/0013—Protection against corrosion
Definitions
- the present inventions relate generally to providing support for a face of a passage in a geological structure and, more particularly, to a tensionable spiral bolt associated with a resin nut partially occupying a borehole and related methods.
- one of the major areas for lowering the manufacturing cost and installation time for such bolts involves reducing the diversity, complexity, and overall number of the parts required. This includes eliminating the need for specialized expansion shells, external nuts, or other attachments to the bolt required in the past to effect proper tensioning. Extensive processing of the bolt shaft typically necessary for accommodating these types of expansion shells or external nuts should also be eliminated, since tin ' s activity not only increases manufacturing time and expense, but also tends to weaken the bolt and the resulting assembly. Accordingly, a need exists for an improved bolting apparatus that overcomes the foregoing limitations of the prior art. Specifically, the bolt should be easy and inexpensive to manufacture and install. The bolt would be also be tensionable to compress and provide secure, reliable support for the adjacent strata once installed.
- an apparatus for installation in a borehole formed in a face of a mine passage comprises an elongated bolt including a spiral shaft portion for positioning in the borehole.
- a stationary, hardened resin nut is formed in a portion of the borehole for surrounding at least part of the spiral shaft portion of the bolt. Rotation of the spiral shaft portion within the resin nut thus serves to move the bolt within the borehole, such as during tensioning.
- the spiral shaft portion comprises a generally circular cross section, and may include approximately 4-5 threads for about every inch in the longitudinal direction.
- at least part of the spiral portion may include a lubricity or rust-inhibiting agent.
- a colored agent is also applied along at least part of the spiral shaft portion to allow for identification of the bolt for use with the resin nut.
- the bolt may include a head end and a tail end as well.
- the tail end for advancing into the borehole may include a taper or point.
- the construction of the bolt is such that it is formed of a single piece of material.
- a flange may also be provided adjacent the head end, with one side for engaging a plate or like structure adjacent the mine face and the opposite side providing a bearing surface for a device or means for rotating the bolt.
- an apparatus for installation in a borehole formed in a face of a mine passage comprises an elongated bolt including a portion, such as for example a spiral portion, for positioning in the borehole.
- a stationary, hardened resin nut is also provided for receiving a portion of the bolt.
- the apparatus further includes means for rotating the bolt relative to the hardened resin nut, preferably in the form of a drill head.
- an improvement for use in a borehole formed in a face of a mine passage for receiving a bolt having an elongated shaft for extending into the borehole.
- the improvement comprises a resin nut formed in a portion of the borehole and having an internal thread surrounding only a portion of the shaft.
- the shaft of the bolt is spiral, whereby rotating the spiral shaft relative to the internal thread serves to tension the bolt.
- a roof bolt for insertion in a borehole formed in a face of a mine passage.
- the bolt comprises a shaft having a spiral portion at least partially having a coating selected from the group consisting of a lubricity agent, a rust- inhibiting agent, a colored agent and mixtures thereof.
- the coating is at a distal end of the shaft having a point for insertion in the borehole.
- a method of tensioning a bolt including a spiral shaft portion in a borehole formed in a face of a mine passage is disclosed. The method comprises forming a stationary, hardened resin nut adjacent at least the spiral shaft portion of the bolt. The method further comprises rotating the spiral shaft portion relative to the hardened resin nut.
- the forming step comprises: (1) providing uncured resin within the borehole adj acent the spiral shaft portion of the bolt; (2) rotating the bolt in a first direction to substantially maintain the resin adjacent the spiral shaft portion; and (3) allowing the resin to substantially cure and form the hardened resin nut.
- the step of rotating the bolt preferably comprises rotating the spiral shaft portion in a second direction opposite the First direction upon the substantial curing of the resin.
- the method may further include the step of applying a lubricity or rust-inhibiting agent to at least part of the spiral shaft portion.
- a method of installing an elongated bolt having a head end and a threaded or spiral portion in a face of a mine passage having a borehole comprises inserting the bolt at least partially within the borehole with the head end spaced from the opening.
- the bolt is rotated in a first direction and at least partially within an uncured resin within the borehole, and the resin is allowed to substantially cure and form a nut.
- the bolt is rotated in a second direction opposite the first direction such that the bolt moves through the resin nut with the head end moving closer to the opening of the borehole.
- the head end of the bolt is initially spaced from the open end of the borehole, and the step of rotating the bolt in the second direction advances the head end of the bolt toward the open end of the borehole.
- Figure 1 is an elevational view, not to scale, of one possible embodiment of a roof bolt with a spiral portion;
- Figures 1 a and 1 b are cross-sections taken along lines 1 a- 1 a and 1 b-
- Figures Ic and Id show an alternate spiral bolt
- Figures 2-4 are schematic diagrams showing the manner hi which the spiral bolt of Figure 1 may be tensioned using a resin nut formed in the borehole.
- Figure 1 illustrates one embodiment of a bolt 10 for installation in a face F of a mine passage, such as the roof (see Figure 2) having a borehole H formed vertically therein.
- a bolt 10 and related installation method are described as being used to reinforce and sustain a mine roof, it should be understood that the present invention may be applied to support any one of the other faces of the passage (e.g., a rib) or a different type of geological structure, without limitation.
- the bolt 10 is preferably an elongated, one-piece structure comprising a head end 10a, an elongated body or shaft 10b, and a tail end 10c.
- the head end 10a is adapted for being engaged by a wrench, chuck of a drill head (see Figure 2), or like device or means for rotating the bolt 10 during installation.
- Figure Ia it should be appreciated that the head end 10a of the bolt 10 may take on other cross- sectional shapes (e.g., hexagonal) without impacting the practice of the present invention in any meaningful way.
- An annular flange 11 is also provided adjacent the head end 10a to provide a bearing surface for the means for rotating on one side and the face or intervening structure (such as plate P; see Figure 2) on the other.
- the shaft 10b of the bolt 10 is generally square in cross-section (see Figure Ib), but is "twisted” or threaded along its length to form a spiral or helix, hi the illustrated embodiment of Figure 1 , the spiral extends along the entire length of the shaft 10b, and is left- handed in nature (but could be the opposite as well).
- the arrangement is preferably coarse in nature (equal to or greater than about four threads per inch, up to about seven per foot).
- the shaft 1 Ob of the bolt 10 is shown as being generally round in cross-section, and includes a spiral portion formed by threads T.
- each inch of the spiral shaft 10b preferably includes between about 4 to 5 complete (e.g., 360°) threads.
- each complete thread occupies about 0.22 inches of distance in the longitudinal direction, or length, which corresponds to about 4.5 complete twists per linear inch (see reference character d representing pitch in Figure Id).
- a corresponding thread is formed in the resin nut once it is formed in the borehole and the threaded spiral bolt 10 installed in the manner described in the foregoing passage.
- the spiral may be provided along only a portion of the shaft 1 Ob.
- the spiral is along the tail end 10c, or otherwise away from the head end 10a.
- FIG. 2 which although not drawn to scale, illustrates schematically the manner in which the bolt 10 of Figure 1 is installed in the borehole H.
- the tail end 10c of the bolt 10 is inserted through the opening O of the borehole H, which is preferably formed having a diameter close to the width M of the spiral shaft 1 Ob (e.g. , 3/4" for a 1 inch diameter borehole).
- the borehole H also preferably has a depth D greater than at least the spiral shaft 10b, and preferably greater than the length of the entire bolt 10 (e.g.. dimension B in Figure 1) by at least one inch.
- the bolt 10 is advanced into the borehole H such that the head end 1 Oa remains spaced from the adj acent face of the roof a distance equal to or slightly less than the excess depth D of the borehole H (e.g., about two inches).
- a plate P is typically associated with the head end 10a of the bolt 10, and would thus also be spaced from the face F. However, once the bolt 10 is tensioned in the manner described below, this plate P engages the face F and compresses the associated strata (see Figure 4).
- uncured resin also sometimes referred to as "grout" is provided adjacent at least a portion of the spiral shaft 10b in the associated a ⁇ nulus (which is shown in Figure 2 as being greatly oversized for purposes of illustration, but is normally only about l/8"-l/4" on either side).
- the uncured resin occupies the anmilus adjacent the tail end 10c of the bolt 10, and in the upper portion of the borehole H.
- the uncured resin may be provided from a remote source, such as by way of injection, it is most preferably supplied in the form of a frangible cartridge (not shown), or resin "sausage" in the vernacular.
- this type of cartridge is pre-installed in the borehole H and ruptured during insertion of the bolt 10, thus causing a quick-curing resin to occupy the surrounding borehole H.
- This "grout" usually comprises two materials (e.g., polyester resin and a catalyst paste) that make contact and react only upon the rupturing of the cartridge. Upon being thoroughly mixed, such as by the rotation of the bolt 10 within the borehole H, the resin then quickly hardens. The hardened resin or grout thus serves to hold the bolt 10 securely within the borehole H.
- the bolt 10 witli the spiral shaft 1 Ob at least partially surrounded by uncured resin is rotated to effect the desired mixing and/or hardening, such as by using any conventional type of bolting machine.
- the rotation is in the opposite, or right-handed, direction (see action arrow R in Figure 2).
- this rotation is done without simultaneously advancing the bolt 10 within the borehole H any significant amount, such that it remains spaced from the opening O of the borehole H.
- this rotation in combination with the spiral shaft 1 Ob serves to create a "pumping" action that substantially holds the uncured resin in place, and may possibly advance or "push” this resin deeper within the borehole H.
- the spiral shaft 10b of the bolt 10 may essentially function as an auger or screw with flights that maintain the resin at a particular location within the upper end of the borehole H.
- the rotation of the spiral shaft 10b preferably is such that it prevents the uncured resin from advancing toward the opening O of the borehole H to any significant degree. As a result of this pumping action, once the resin sets or cures (normally, after a period of rest post- mixing), it surrounds only a portion of the spiral shaft 10b within the borehole H.
- the amount of resin supplied will of course depend on the relative sizes of the spiral shaft 10b and the borehole H, but is preferably sufficientto cover about 12-18 inches of the shaft 10b adjacent the tail end 10c or otherwise away from the head end 10a (which, of course, still remains spaced from the opening O of the borehole H).
- a stationary, hardened resin "nut” 12 is thus formed around at least a portion of the spiral shaft 10b in the borehole H.
- this resin nut 12 has an internal thread matching the spiral thread of the adjacent shaft 1 Ob and occupied by it.
- the bolt 10 may be rotated in a direction opposite the first direction (note action arrow L) and in the same direction as the spiral .
- the engagement between the spiral shaft 10b and the resin nut 12 causes the bolt 10 to advance within the borehole H when so rotated, thus moving the head end 10a closer to the adjacent opening O.
- the hardened resin nut 12 remains stationary due to the peripheral contact with the sidewall of the borehole H.
- the bolt 10 in the preferred embodiment may be made of only one piece of material, and need not include any expansion shells or external nuts in order to be effective. Accordingly, no parts require assembly "on-site.” This not only substantially reduces the manufacturing cost, but also facilitates ease of installation and results in a stronger bolt. Additionally, only partial grouting of the borehole is required for effectively practicing the present invention. Thus, substantially less grout is required, as compared to arrangements in which the borehole is fully grouted. A concomitant savings in material cost invariably results (possibly as much as 75%), as well as a reduction in the cost of transporting the grout into the mine and maintaining it in a "ready for use" state.
- the completed installation of the bolt 10 also advantageously results in the head end 10a being positioned extremely close to face F of the mine roof (see Figure 4).
- the bolt 10 can be manufactured in a relatively easy and inexpensive manner.
- Square or round bar stock of any suitable width dimension (e.g., 1 A", 5/8", or 3/4" for a 1" borehole) can simply be worked to the desired pitch (whether considered twists per linear unit, or thread-to-thread spacing) to form the shaft 10b.
- the head end 10a is typically forged.
- the spiral can also be formed on a relatively long piece of stock, which can then be cut into lengths corresponding to the shaft 10b of the bolt 10.
- the working applied to the bar may result in the elimination of the exterior surface oxide layer, or "scale,” created during the hot roll process.
- the absence of the scale allows faster oxidation of the bar, especially when the bolt 10 is stored outdoors and exposed to the elements during the period between manufacturing and ultimate use in the mine. Any deterioration of the surface may inhibit the ability of the shaft 10b to turn freely within the resin nut 12 during installation.
- the spiral shaft 10b (such as the uppermost portion) after manufacture with either a lubricity agent or a rust-inhibiting agent, or both.
- a lubricity agent or a rust-inhibiting agent or both.
- the partial or full application of such agent(s) is anticipated to ease the installation by allowing the spiral shaft 1 Ob to rotate more freely relative to the resin nut 12 during tensioning.
- Providing any coating agent with a coloring e.g., a yellow pigment
- the installer may not only ensure that the coating remains present on an appropriate portion of the shaft 10b, but also can readily differentiate the spiral bolts 10 for use in the present method from others.
- the pitch of the spiral may be varied, it is also desirable to ensure that the spiral bolts 10 for use in a common installation are consistent. This keeps the installation torque required consistent.
- the spiral shaft 10b should also be consistent to facilitate its movement through the resin nut 12 once formed.
- the pitch of the spiral is also preferably such that there is noticeable movement of the head end
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US2008/055908 WO2009110894A1 (en) | 2008-03-05 | 2008-03-05 | Tensionable spiral bolt with resin nut and related method |
CN2008801277705A CN101983277A (en) | 2008-03-05 | 2008-03-05 | Tensionable spiral bolt with resin nut and related method |
AU2008352050A AU2008352050B2 (en) | 2008-03-05 | 2008-03-05 | Tensionable spiral bolt with resin nut and related method |
US12/313,149 US7758284B2 (en) | 2006-10-09 | 2008-11-17 | Tensionable spiral bolt with resin nut and related method |
ZA2010/06283A ZA201006283B (en) | 2008-03-05 | 2010-09-02 | Tensionable spinal bolt with resin nut and related methods |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US2008/055908 WO2009110894A1 (en) | 2008-03-05 | 2008-03-05 | Tensionable spiral bolt with resin nut and related method |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/539,654 Continuation-In-Part US7481603B1 (en) | 2005-10-07 | 2006-10-09 | Tensionable spiral bolt with resin nut and related method |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/313,149 Continuation US7758284B2 (en) | 2006-10-09 | 2008-11-17 | Tensionable spiral bolt with resin nut and related method |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2009110894A1 true WO2009110894A1 (en) | 2009-09-11 |
Family
ID=41056291
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2008/055908 WO2009110894A1 (en) | 2006-10-09 | 2008-03-05 | Tensionable spiral bolt with resin nut and related method |
Country Status (4)
Country | Link |
---|---|
CN (1) | CN101983277A (en) |
AU (1) | AU2008352050B2 (en) |
WO (1) | WO2009110894A1 (en) |
ZA (1) | ZA201006283B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
RU2631500C2 (en) * | 2010-02-08 | 2017-09-25 | Лантеус Медикал Имаджинг, Инк. | Methods and apparatus for synthesizing imaging agents, and intermediates thereof |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4305687A (en) * | 1979-01-26 | 1981-12-15 | Jack Parker | Anchoring system for rock bolts |
US4386877A (en) * | 1979-03-28 | 1983-06-07 | Peabody Coal Company | Mine roof bolting |
US4564315A (en) * | 1983-07-05 | 1986-01-14 | Rozanc Richard C | Method for anchoring a bolt in a rock-like structure |
US4642964A (en) * | 1984-09-27 | 1987-02-17 | Kellison Roger C | Grout in place fastener system |
US5013192A (en) * | 1982-06-25 | 1991-05-07 | Scott Investment Partners | Dynamic rock stabilizing fixture |
US6698980B2 (en) * | 2001-07-30 | 2004-03-02 | Stewart Mining Products Inc. | Rock stabilizing apparatus and method |
-
2008
- 2008-03-05 AU AU2008352050A patent/AU2008352050B2/en not_active Ceased
- 2008-03-05 CN CN2008801277705A patent/CN101983277A/en active Pending
- 2008-03-05 WO PCT/US2008/055908 patent/WO2009110894A1/en active Application Filing
-
2010
- 2010-09-02 ZA ZA2010/06283A patent/ZA201006283B/en unknown
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4305687A (en) * | 1979-01-26 | 1981-12-15 | Jack Parker | Anchoring system for rock bolts |
US4386877A (en) * | 1979-03-28 | 1983-06-07 | Peabody Coal Company | Mine roof bolting |
US5013192A (en) * | 1982-06-25 | 1991-05-07 | Scott Investment Partners | Dynamic rock stabilizing fixture |
US4564315A (en) * | 1983-07-05 | 1986-01-14 | Rozanc Richard C | Method for anchoring a bolt in a rock-like structure |
US4642964A (en) * | 1984-09-27 | 1987-02-17 | Kellison Roger C | Grout in place fastener system |
US6698980B2 (en) * | 2001-07-30 | 2004-03-02 | Stewart Mining Products Inc. | Rock stabilizing apparatus and method |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
RU2631500C2 (en) * | 2010-02-08 | 2017-09-25 | Лантеус Медикал Имаджинг, Инк. | Methods and apparatus for synthesizing imaging agents, and intermediates thereof |
Also Published As
Publication number | Publication date |
---|---|
AU2008352050A1 (en) | 2009-09-11 |
ZA201006283B (en) | 2014-03-26 |
CN101983277A (en) | 2011-03-02 |
AU2008352050B2 (en) | 2015-07-02 |
AU2008352050A2 (en) | 2010-09-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7758284B2 (en) | Tensionable spiral bolt with resin nut and related method | |
US7896581B2 (en) | Re-tensionable cable bolt apparatus and related method | |
US8807877B1 (en) | Tensionable spiral bolt with resin nut and related methods | |
US8434970B2 (en) | Breakable rock bolt | |
US8033760B2 (en) | Tension assembly | |
US6402433B1 (en) | Tensionable mine roof bolt | |
CN109477383B (en) | Corrosion-resistant retractable anchor rod | |
US7481603B1 (en) | Tensionable spiral bolt with resin nut and related method | |
US6986623B2 (en) | Method and apparatus for anchoring a mine roof bolt | |
CA2452271C (en) | An improved apparatus for ground support | |
US20140308081A1 (en) | Tensionable elongated bolt disposed with a sleeve and method of use thereof | |
AU2008352050B2 (en) | Tensionable spiral bolt with resin nut and related method | |
AU2016102140A4 (en) | Rock bolt | |
US20100266345A1 (en) | Engagement head for tensioning assembly | |
US8550751B2 (en) | Non-tensionable cable bolt apparatus and related method | |
AU2008362189A1 (en) | Re-tensionable cable bolt apparatus and related method | |
US20030210967A1 (en) | Roof bolts for use in mines, a method for their production and a method for their installation | |
AU2007221783B2 (en) | Rock bolt | |
AU2014203250B2 (en) | Rock bolt | |
AU2007221867B2 (en) | A breakable rock bolt | |
AU2012202308B2 (en) | Mining rock bolt | |
AU2015261553B2 (en) | Tension assembly | |
WO2021087574A1 (en) | Rock bolt | |
AU2012202298A1 (en) | Rock bolt | |
WO2011026178A1 (en) | Tensioning device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200880127770.5 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 08731435 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2008352050 Country of ref document: AU |
|
ENP | Entry into the national phase |
Ref document number: 2008352050 Country of ref document: AU Date of ref document: 20080305 Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 08731435 Country of ref document: EP Kind code of ref document: A1 |