Granted Patent
Utility
US 4,577,796 · App. 06/658,992
Method and apparatus for tracking seam welds on pipes and the like
Inventors:
Joseph E. Powers, Calvin C. Williamson
Patented Case
View Patent ↗
Granted: Mar 25, 1986
Filed: Oct 10, 1984
Inventors
Joseph E. Powers
Calvin C. Williamson
Assignee (at issue)
Kaiser Steel Corporation
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.