In order to have the ground freezing, mine shaft sinking and grouting operations done at the same time during the mine shaft construction, taking the surface pre-grouting project of Xuandong Ventilation Shaft as the example, the controlled directional drilling technology was successfully to combine the directional wedges and screw pipe drill. The paper had a reversed calculation on the reversed torque angle and inclined rate. The paper with the diagram method analyzed the relationship of the point angle position. With the man controlled borehole drilling tracing tendency, the boreholes drilled with the technology could meet the requirements of the underground pro- ject. The three operations could be done at the same time and construction period was reduced.
Coal Science and Technology
controlled drilling technology