Patent ID: 7708072
Filing Date: 2010-05-04
Classification: E21B

Abstract:
1. A method of withdrawing a string or end-to-end assembly of hollow stem auger sections from a bore hole for a well, comprising the steps of: given an above-ground stub of the string, engaging some portion of the above-ground stub's helical flighting from underneath with a retractor; and applying a lifting force through the retractor in order to withdraw the string or end-to-end assembly of hollow stem auger sections by some measure at least greater than one section; wherein the step of engaging some portion of the above-ground stub's helical flighting from underneath with a retractor further comprises providing the retractor with a C-shaped inter-coil insertion and inserting such in a gap between a coil of the helical flighting such that the C-shaped inter-coil insertion straddles the stem and engages some portion of the helical flighting from underneath.