KELLY DRIVE BUSHING ADAPTER

摘要

KELLY DRIVE BUSHING ADAPTERABSTRACT OF THE DISCLOSUREAn adapter is provided for positioning a kelly drivebushing of a surface drilling assembly in spaced relationshipto an associated rotary table. The adapter permits thewireline of an electronic steering assembly to pass throughthe central aperture in the rotary table below the drivebushing to surface readout equipment, enabling the electronicsteering assembly to be employed for drilling directionalbores without removal of the kelly.