Trenchless directional drilling construction process-1

Trenchless directional drilling construction process-1

The directional drill crosses and controls the direction. In the process of pilot hole drilling, the wireless direction control system is used, and the ground beacon system is arranged on the center lines of both sides of the entry and exit points. The signal connected in the drill pipe feeds back the position of the drilling tool to the direction control room so that the driller can grasp the tool surface at any time And the azimuth, the ground beacon system can accurately find the azimuth crossing the centerline, and effectively prevent the interference of external magnetic fields.

Drill pilot holes

(1) The drill tool combination for drilling pilot holes is: pilot bit + drill rod. The steering instrument unit assembly is installed in the steering bit and tightened.

(2) Use theodolite to find out the exact position of crossing the center line before drilling, and make a mark to control the left and right deviation of the steering based on this.

(3) Target of pilot hole drilling accuracy: the longitudinal deviation of the excavation point along the design curve should be no more than 1% of the traverse length and no more than 0.3m; the lateral deviation should be no more than 1.5% of the traverse length and no more than 0.45m.