Granted Patent
Utility
US 5,479,721 · App. 08/220,281
Method and apparatus for measuring the length (MIU) of the internal taper of an internally upset drill pipe tube
Inventor:
Nels Peter Wickander
Patented Case
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Granted: Jan 2, 1996
Filed: Mar 30, 1994
Inventor
Nels Peter Wickander
Assignee (at issue)
Prideco, 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.