Patent ID: 11898405
Assignee: THE CHARLES MACHINE WORKS, INC.
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 10:
11. A method of using a system, the system comprising:
an underground borehole having an entry point and an exit point;
a pilot drill situated adjacent the entry point;
an exit-side drill situated adjacent the exit point and comprising:
a carriage supported on a drill frame and movable relative to the drill frame;
a rotary spindle supported on the carriage;
a rotary motor supported on the carriage and coupled to the rotary spindle; and

a drill string comprising a plurality of first pipe sections, the drill string having a first end and a second end; in which the first end is operatively connected to the pilot drill; and
a second pipe section;
in which the method comprises:
rotating and advancing the drill string to the exit point using the pilot drill;
thereafter, connecting the second pipe section to the rotary spindle;
thereafter, rotating the second pipe section using the rotary spindle and connecting the second pipe section to the second end of the drill string, in which rotation of the rotary spindle is driven by the rotary motor;
thereafter, stopping the rotary motor from driving rotation of the rotary spindle;
thereafter, pulling and rotating the drill string and the second pipe section using the pilot drill; and
simultaneously with the step of pulling and rotating, engaging the second pipe section with the rotary spindle while the carriage moves relative to the drill frame.