Granted Patent
Utility
US 6,755,444 · App. 10/251,881
Slim-type threaded joint for oil well pipes
Inventors:
Katsutoshi Sumitani, Jun Maeda, Shigeo Nagasaku
Patented Case
View Patent ↗
Granted: Jun 29, 2004
Filed: Sep 23, 2002
Inventors
Katsutoshi Sumitani
Jun Maeda
Shigeo Nagasaku
Assignees (at issue)
SUMITOMO METAL INDUSTRIES, LTD.
VALLOUREC MANNESMANN OIL & GAS FRANCE
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.