IP Library › Granted Patent US 4,926,945
Granted Patent Utility
US 4,926,945 · App. 07/404,241

Subsurface well safety valve with curved flapper and method of making

Inventors: Ronald E. Pringle, Arthur J. Morris
Patented Case View Patent ↗
Granted: May 22, 1990 Filed: Sep 7, 1989
Inventors
Ronald E. Pringle
Arthur J. Morris
Assignee (at issue)
Camco Inc.

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Quick Facts
Patent No.
US 4,926,945
App. No.
07/404,241
Filed
1989-09-07
Granted
1990-05-22
Kind
A