ROTARY DRIVE CONNECTION FOR CASING DRILLING STRING

摘要

A drive connection for connecting a rotary power source to a string of well casing employed as a rotary drilling string. The drive connection is designed to be insertible in the upper end of the casing and is provided with a mandrel carrying slips and a slip expander for gripping the interior of the casing and pipe-gripping shoes operable in response to angular movement of the mandrel to apply torsional force to the casing.