IP Library › Granted Patent US 4,358,085
Granted Patent Utility
US 4,358,085 · App. 06/285,677

Keying means for segmented end ring blowout preventer

Inventors: John Regan, Bruce J. Watkins
Patented Case View Patent ↗
Granted: Nov 9, 1982 Filed: Jul 20, 1981
Inventors
John Regan
Bruce J. Watkins
Assignee (at issue)
Hughes Tool Company LLC

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Quick Facts
Patent No.
US 4,358,085
App. No.
06/285,677
Filed
1981-07-20
Granted
1982-11-09
Kind
A