06068069 is referenced by 31 patents and cites 55 patents.

A multi-activity drillship, or the like, method and apparatus having a single derrick and multiple tubular activity stations within the derrick wherein primary drilling activity may be conducted from the derrick and simultaneously auxiliary drilling activity may be conducted from the same derrick to reduce the length of the primary drilling activity critical path.

Title
Multi-activity offshore exploration and/or development drilling method and apparatus
Application Number
642417
Publication Number
6068069
Application Date
April 14, 1999
Publication Date
May 30, 2000
Inventor
Donald R Ray
Houston
TX, US
Robert P Herrmann
Houston
TX, US
Robert J Scott
Sugarland
TX, US
Agent
Kile McIntyre Harbin & Lee
Agent
Richard A Sterba
Bradford E Kile
Assignee
Transocean Offshore
TX, US
IPC
E21B 7/12
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