IP Library › Granted Patent US 5,086,853
Granted Patent Utility
US 5,086,853 · App. 07/670,249

Large bore hydraulic drilling jar

Inventor: Robert W. Evans
Patented Case View Patent ↗
Granted: Feb 11, 1992 Filed: Mar 15, 1991
Inventor
Robert W. Evans

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Quick Facts
Patent No.
US 5,086,853
App. No.
07/670,249
Filed
1991-03-15
Granted
1992-02-11
Kind
A