Mine roof bolts
United States Patent 3301123
US Patent References:
Anchor device
- - 1864300
Mine roof bolts having segmented shell biased outwardly by resilient washer
- - 2878709
Plastic screw anchor
- - 3232163
Anchor device
- - 1864300
Mine roof bolts having segmented shell biased outwardly by resilient washer
- - 2878709
Plastic screw anchor
- - 3232163
Inventors:
Worley, William E.
Publication Date:
01/31/1967
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Export Citation:
Assignee:
Worley, William E.
Primary Class:
Other Classes:
405/259.100
International Classes:
E21D21/00; F16B13/08; F16B13/04
Foreign References:
| GB711324A |