摘要 |
A non-removable, tamper-proof bolt has a threaded shaft, a permanent head, and a torque head which is sheared off from the assembly when the bolt is fastened. The shaft has an opening formed therein at the forward screw end, and the opening has a profile for engagement with a torque tool. The torque head is formed with a hole as well which extends through the entire torque head coaxially with the threaded shaft. The torque head is attached to the permanent head by the intermediary of a bridge defined around said hole in the torque head. Once the torque head is sheared off, the bolt cannot be turned until the opening formed in the forward screw end is exposed by drilling through the shaft from the permanent head inwardly.
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