Roof bolt apparatus with expansion shell and coupling
An apparatus is described for supporting a rock formation comprising: an elongated rod positioned in a bore hole of a rock formation; the rod having a first threaded end portion and a second threaded end portion positioned adjacent the end of the bore hole; an expansion shell assembly engaged to the rod first threaded end portion, an elongated bolt positioned in the bore hole below the rod second threaded end portion, the bolt having a first threaded end portion and a second end portion; the bolt first threaded end portion positioned oppositely of the rod second threaded end portion; a bearing plate positioned on the bolt second end portion; means for threadedly connecting the bolt to the rod, stop means associated with the means for threadingly connecting the bolt to the rod for limiting axial movement of the bolt relative to the rod to permit unitary rotation of both the bolt and the rod in a preselected direction; the expansion shell assembly operable upon rotation of the rod to anchor the rod in the bore hole; and the bolt being operable to rotate in the preselected direction relative to the rod anchored in the bore hole to disengage the stop means to axially advance the bolt relative to the rod and tension bolt.
- Assignee:
- Jennmar Corp., Pittsburgh, PA
- Patent Number(s):
- US 4679966
- OSTI ID:
- 6357017
- Resource Relation:
- Patent File Date: Filed date 17 Sep 1986
- Country of Publication:
- United States
- Language:
- English
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