Underreamer base plate recovery device

摘要

A device for recovering a detachable base 12 of a soil working tool 10 from the bottom of a hole, includes a releasable clamping tool 22 which is adapted to engage a pin 16 formed on the base 12 when the clamping tool 22 is lowered onto the base 12. The invention also relates to a detachable base 12 per se, and a method of operating a soil working tool 10 including clamping and withdrawal of the detachable base 12 from a bore hole by means of a clamping tool 22.