| 摘要 |
A roof bolt has a bolt shaft, external threads affixed to the bolt shaft, and a cover. The cover has internal threads threadably engaging the external threads. The cover encloses the internal and external threads so as to protect the internal and external threads and to facilitate a consistent pre-established torque vs. tension relationship. The cover has a drive portion arranged to accept a drive tool so that torque may be applied to the roof bolt.
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