Granted Patent
Utility
US 4,525,616 · App. 06/567,738
Internal pipe welding apparatus
Inventor:
Clyde M. Slavens
Patented Case
View Patent ↗
Granted: Jun 25, 1985
Filed: Jan 3, 1984
Inventor
Clyde M. Slavens
Assignee (at issue)
Evans Pipeline Equipment 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.