Granted Patent
Utility
US 4,502,886 · App. 06/455,990
Austenitic stainless steel and drill collar
Inventors:
James N. Cordea, Joseph C. Jasper, Harshad V. Sheth
Patented Case
View Patent ↗
Granted: Mar 5, 1985
Filed: Jan 6, 1983
Inventors
James N. Cordea
Joseph C. Jasper
Harshad V. Sheth
Assignee (at issue)
Armco Inc.
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.