ALEXANDRIA, Va., June 17 -- United States Patent no. 12,312,891, issued on May 27, was assigned to ConocoPhillips Co. (Houston).
"Method and apparatus for milling a window in casing" was invented by Kenneth Maribu (Tananger, Norway), John Gary Eller (Longview, Texas) and Anthony Ryan (Houston).
According to the abstract* released by the U.S. Patent & Trademark Office: "A process is described for milling a window in the casing (2) of an oil or gas producing well, for example in order to drill a lateral well branching off from the main well. A wireline milling tool is first used, in a relatively low cost operation, to create a small window (14) or notch in the casing (2). Provided a small window (14) or notch can be created successfully, an...