A pilot bore is drilled from a launch pit at one end of the planned trenchless installation, along a predetermined route, to an exit pit at the other end of the trenchless installation.
The drill head contains a transmitting device by means of which the position, depth, pitch and roll of drill head can be monitored as the pilot drill progresses. Adjustments to the line and level can be made throughout the pilot drilling process thereby achieving the planned bore profile.
When the pilot bore is complete, the drill head is removed from the drill string and replaced with an appropriate hole opening device. This is rotated and pulled back through the bore thereby increasing the hole diameter.
When the bore is of sufficient size the pipe is attached by means of a swivel and towing head and installed as the drill string is retracted to complete the trenchless pipe installation.
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