Sinorock drill hollow bolt is developed with high tensile load and pressure resistance. It combines rock bolt with injection function and is widely used in geotechnical engineering projects such as tunnel reinforcement/refurbishment, cliff and slope reinforcement, wall stabilization, rock-netting retention, parapet wall reinforcement and many others. After injection work, the bolt can remain in the borehole and bear load with plate and nut at the end. It has very good bonding force with all grouting materials. Due to high injection pressure, it can realize full grouting and improve project quality.
Manufactured with the best quality of materials Sinorock hollow anchor bolt has many advantages. It has good penetrability in various types of rocks and after the construction there is no requirement to pull the hollow anchor bolt out. The penetrability bit is on the higher side and the plates and nuts are of higher strength. It substantiates three operations as a whole - drilling, anchoring and grouting. The stress that surrounds the rock is evenly shifted to the wall, which results in providing support to each other amid the anchor and adjoining rock. When high rates of grouting pressure is maintained, the cracks get completely filled and the overall fractured rock is made better.

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