Granted Patent
Utility
US 4,611,630 · App. 06/678,657
Single hydraulic line choke valve system
Inventors:
John D. Muchow, Kenneth L. Pelata
Patented Case
View Patent ↗
Granted: Sep 16, 1986
Filed: Dec 6, 1984
Inventors
John D. Muchow
Kenneth L. Pelata
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.