IP Library › Granted Patent US 4,816,551
Granted Patent Utility
US 4,816,551 · App. 07/028,423

Oil based drilling fluids

Inventors: Harris A Oehler, Henry C. McLaurine, Charles K. Grantham
Patented Case View Patent ↗
Granted: Mar 28, 1989 Filed: Mar 20, 1987
Inventors
Harris A Oehler
Henry C. McLaurine
Charles K. Grantham
Assignee (at issue)
M-I Drilling Fluids

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Quick Facts
Patent No.
US 4,816,551
App. No.
07/028,423
Filed
1987-03-20
Granted
1989-03-28
Kind
A