Granted Patent
Utility
US 5,551,521 · App. 08/323,152
Method and apparatus for cementing drill strings in place for one pass drilling and completion of oil and gas wells
Inventor:
William Banning Vail, III
Patented Case
View Patent ↗
Granted: Sep 3, 1996
Filed: Oct 14, 1994
Inventor
William Banning Vail, III
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.