Claims
- 1. A tensionable cable mine roof bolt comprising:
- an elongated member having an upper portion adapted to be resin grouted within a bore hole in rock and an intermediate portion having a mechanical anchor for engaging with the rock surrounding the bore hole, and an end portion having a bolt head drivable by mine roof bolt installation equipment, said upper portion comprising a length of multi-strand cable, whereby when said bolt is rotated, said elongated member rotates and said mechanical anchor engages with the rock surrounding the bore hole thereby tensioning said bolt and said upper portion simultaneously mixes resin within the bore hole.
- 2. The tensionable cable mine roof bolt as claimed in claim 1 wherein said bolt head comprises a drivehead attached to said end portion of said elongated member, whereby when resin is inserted into the bore hole and said drivehead is rotated by mine roof bolt installation equipment, said upper portion rotates and mixes the resin and said intermediate portion engages with the rock.
- 3. The tensionable cable mine roof bolt as claimed in claim 1 wherein said cable includes a first end, a second end and a mixing portion disposed between said first and second ends, and wherein said bolt further includes an externally threaded shaft attached to said cable, said mechanical anchor being threaded onto said threaded shaft.
- 4. The tensionable cable mine roof bolt as claimed in claim 3 wherein said shaft is hollow and said cable extends through said shaft.
- 5. The tensionable cable mine roof bolt as claimed in claim 4 wherein said drivehead is press fitted onto said cable first end.
- 6. The tensionable cable mine roof bolt as claimed in claim 4 further comprising a barrel and wedge assembly attached to said cable between said drivehead and said shaft.
- 7. The tensionable cable mine roof bolt as claimed in claim 6 wherein said drivehead is adapted to break away from said cable when said bolt is tensioned to a predetermined load.
- 8. The tensionable cable mine roof bolt as claimed in claim 4 wherein said shaft is swaged to said cable.
- 9. The tensionable cable mine roof bolt as claimed in claim 3 wherein said threaded shaft includes twelve threads per inch.
- 10. The tensionable cable mine roof bolt as claimed in claim 3 further comprising a coupler body coupling said cable to said threaded shaft.
- 11. The tensionable cable mine roof bolt as claimed in claim 3 wherein said cable includes a plurality of strands wrapped around each other and wherein said mixing portion comprises a region of said cable wherein said strands are spaced apart from each other.
- 12. The tensionable cable mine roof bolt as claimed in claim 11 wherein said mixing portion includes a plurality of regions in which said strands are spaced apart from each other.
- 13. The tensionable cable mine roof bolt as claimed in claim 12 wherein said cable includes a central strand and a plurality of surrounding strands and said bolt further comprises a nut, said nut being received on said central strand in one of said regions.
- 14. The tensionable cable mine roof bolt as claimed in claim 13 wherein said nut is positioned about three feet from said second end of said cable.
- 15. The tensionable cable mine roof bolt as claimed in claim 14 further comprising a sleeve mounted on said cable second end whereby an end of each said strand is fixed within said sleeve.
- 16. A tensionable cable mine roof bolt for insertion into a bore hole in rock and adapted to be resin grouted, said bolt comprising:
- a bearing plate;
- a barrel and wedge assembly supporting said bearing plate;
- a multi-strand cable having a first end attached to said barrel and wedge assembly and having a resin mixing portion distal from said first end;
- a drivehead mounted on said first end opposite said barrel and wedge assembly from said bearing plate;
- an externally threaded shaft receiving said cable and secured to said cable between said bearing plate and said resin mixing portion; and
- a mechanical anchor threaded onto said shaft, wherein when resin is inserted into the bore hole and said bolt is rotated within the bore hole to mix the resin, said mechanical anchor engages the rock and tensions said bolt.
- 17. The tensionable cable mine roof bolt as claimed in claim 16 wherein said drivehead is releasably mounted on said cable.
- 18. The tensionable cable mine roof bolt as claimed in claim 17 wherein said drivehead is adapted to break away from said cable when said bolt is tensioned to a predetermined load.
- 19. The tensionable cable mine roof bolt as claimed in claim 16 wherein said shaft is swaged to said cable.
- 20. The tensionable cable mine roof bolt as claimed in claim 16 wherein said mixing portion includes a plurality of regions wherein said strands are spaced apart from each other.
- 21. The tensionable cable mine roof bolt as claimed in claim 20 wherein said cable includes a central strand and said bolt further comprises a nut, said nut being received on said central strand in one of said regions.
- 22. The tensionable cable mine roof bolt as claimed in claim 20 wherein prior to installation of said bolt in the bore hole, an outside diameter of one of said regions is larger than an inside diameter of the bore hole.
- 23. A method of installing a cable mine roof bolt in a bore hole formed in the rock of a mine roof comprising the steps of:
- placing a resin cartridge into the bore hole;
- inserting a cable mine roof bolt into the bore hole, the bolt including a cable and a drive head mounted on the bolt at a first end thereof, the cable including a resin mixing portion distal from the first end, the bolt further including a mechanical anchor mounted on the bolt at a position between the drive head and the resin mixing portion; and
- rotating the drive head for simultaneously
- (i) rotating the resin mixing portion to mix the resin and for
- (ii) engaging the mechanical anchor with the rock surrounding the borehole and tensioning the bolt between the mechanical anchor and the mine roof.
- 24. The method of installing a cable mine roof bolt as claimed in claim 23 further comprising tensioning the bolt to a predetermined load.
- 25. The method of installing a cable mine roof bolt as claimed in claim 24 wherein said step of tensioning the bolt to a predetermined load comprises rotating the drivehead until the drivehead breaks free from the bolt.
Parent Case Info
This application claims the benefits of U.S. Provisional Application Ser. No. 60/038,187 entitled "Tensionable Cable Bolt" filed Feb. 14, 1997 and U.S. Provisional Application Ser. No. 60/052,567 entitled "Tensionable Cable Bolt" filed Jul. 15, 1997 and U.S. Provisional Patent Application Ser. No. 60/066,266, entitled "Tensionable Cable Bolt" filed Nov. 20, 1997.
US Referenced Citations (31)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1143471 |
Feb 1963 |
DEX |
Non-Patent Literature Citations (2)
Entry |
Bureau of Mines Information Circular/1994, "Cable Bolt Support Technology in North America", pp. 6-11, Goris et al. |
Product Report 102 BLM Mincon Inc. 1-92, "Preformed Cable Anchor", pp. J01680-83. |