Granted Patent
Utility
US 5,647,572 · App. 08/599,245
Low profile and lightweight high pressure blowout preventer
Inventor:
Charles D. Morrill
Patented Case
View Patent ↗
Granted: Jul 15, 1997
Filed: Feb 9, 1996
Inventor
Charles D. Morrill
Assignee (at issue)
Hydril Company
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.