IP Library › Granted Patent US 4,872,510
Granted Patent Utility
US 4,872,510 · App. 07/252,043

Subterranean well casing float tool

Inventors: Douglas J. Lehr, Merle L. Bell, Richard P. Rubbo, Richard L. Forehand
Patented Case View Patent ↗
Granted: Oct 10, 1989 Filed: Sep 30, 1988
Inventors
Douglas J. Lehr
Merle L. Bell
Richard P. Rubbo
Richard L. Forehand
Assignee (at issue)
Baker Hughes Holdings LLC

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Quick Facts
Patent No.
US 4,872,510
App. No.
07/252,043
Filed
1988-09-30
Granted
1989-10-10
Kind
A