IP Library › Granted Patent US 4,655,431
Granted Patent Utility
US 4,655,431 · App. 06/798,135

Ram-type blowout preventer

Inventors: Paul E. Helfer, Marvin R. Jones
Patented Case View Patent ↗
Granted: Apr 7, 1987 Filed: Nov 13, 1985
Inventors
Paul E. Helfer
Marvin R. Jones

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Quick Facts
Patent No.
US 4,655,431
App. No.
06/798,135
Filed
1985-11-13
Granted
1987-04-07
Kind
A