Crawler system for an earth boring system

摘要

A crawler system for an earth boring system comprises at least two expandable tools along a common axis and spaced apart from each other along the common axis by a piston cylinder device. The at least two expandable tools comprise a mandrel comprising a tubular body and an outer diameter, a plurality of blades, and a slidable sleeve capable of manipulating the plurality of blades into collapsed and expanded positions. The plurality of blades of one of the at least two expandable tools expand to an expanded position and engage a borehole wall. The piston cylinder device anchors against the engagement between the borehole wall and one of the at least two expandable tools to axially translate the other of the at least two expandable tools.