CPC E21B 7/26 (2013.01) [E21B 10/322 (2013.01)] | 21 Claims |
17. A method for maintaining a tunnel having a sidewall defining an interior cavity, said method comprising:
moving a tunneling device through an underground location, the tunneling device including:
a body assembly including a plurality of sections and a force transmitter;
an expander coupled to the body assembly and extending along a longitudinal axis, wherein the expander is expandable in a direction perpendicular to the longitudinal axis between a first configuration having a first width measured perpendicular to the longitudinal axis and a second configuration having a second width measured perpendicular to the longitudinal axis; and
a tip coupled to the expander and configured to move relative to the expander, wherein the expander is disposed between the force transmitter and the tip, wherein the tip has a width measured perpendicular to the longitudinal axis, and wherein the first width of the expander is equal to or less than the width of the tip; and
switching the expander between the first configuration and the second configuration.
|