Patent ID: 6533046
Filing Date: 2003-03-18
Classification: E21B

Abstract:
A drilling apparatus comprising:a magazine for holding a plurality of pipes, the magazine including a plurality of vertical columns; a drive head including a drive member adapted to be coupled to a pipe, the drive member being aligned along a drive axis; a first drive mechanism for rotating the drive member about the drive axis; a second drive mechanism for moving the drive member axially along the drive axis; a pipe transfer member for transferring pipes between the magazine and the drive head, the pipe transfer member defining a pipe receiving region for receiving a pipe, the pipe transfer member being movable to a position where the pipe receiving region is positioned beneath the magazine; and a pipe retainer moveable between a retaining position and a non-retaining position, the pipe retainer preventing lateral movement of a pipe from the pipe receiving region of the pipe transfer member when in the retaining position, the pipe retainer allowing lateral movement of a pipe from the pipe receiving region when in the non-retaining position, the pipe retainer being positioned in the retaining position only when the pipe receiving region of the pipe transfer member is located beneath the magazine.