Granted Patent
Utility
US 4,612,800 · App. 06/720,845
Slurry viscometer
Inventor:
Fadel F. Erian
Patented Case
View Patent ↗
Granted: Sep 23, 1986
Filed: Apr 8, 1985
Inventor
Fadel F. Erian
Assignee (at issue)
Shell Mining Company
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.