| 摘要 |
A mine roof support system is provided which includes a conventional steel anchor rod or bolt, a threaded fastener and a torque indicating member. The anchor rod extends from a distal end portion to an externally threaded proximal end portion. The threaded fastener is a tensioning nut of a conventional design used in mine roof support applications, and is adapted to threadedly engage the proximal end of the anchor rod to tension the anchor rod once secured in a bore hole. The torque indicating member includes one or more radially extending rods, pins, members or planar flanges which are selected to move or distort under a compressive for ce achieved by tightening the nut thereagainst with a first predetermined minimum torque selected less than the torque required to cause tear-out or failure of the anchor rod from the bore hole. The movement of the flanges thus provides a visual indication to an installer that a firs t torque force is being applied.
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