Granted Patent
Utility
US 5,467,824 · App. 08/352,910
Apparatus for and a method of severing multiple casing strings using explosives
Inventors:
Peter L. DeMarsh, William W. Crawford
Patented Case
View Patent ↗
Granted: Nov 21, 1995
Filed: Dec 9, 1994
Inventors
Peter L. DeMarsh
William W. Crawford
Assignee (at issue)
Senior Engineering 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.