The self-drilling hollow rock bolt
GFRP rock bolt increases safety and productivity
We developed a self-drilling GFRP rock bolting system in coal mines for rapid installation and meeting the highest safety requirements.
The advantages of the OneStep bolt system needed the following performance properties:
- Shear strength
- Torsional strength
- Resistant to shock loadings
- Tight tolerances between steel fittings and GFRP rod.
In collaboration with Hilti, we developed the OneStep bolt, consisting of the drill head, FRP tube, and coupling nut complete with internal grout package. The OneStep bolt is easy to install and able to cope with the stresses and shock loading of underground drilling.
The OneStep bolt provides all the advantages of self-drilling steel with the added advantage of cuttability. Overall safety requirements were exceeded and installation speed increased, especially in unstable seams.