Granted Patent
Utility
US 6,127,823 · App. 08/946,989
Electromagnetic method for non-destructive testing of prestressed concrete pipes for broken prestressing wires
Inventor:
David Atherton
Patented Case
View Patent ↗
Granted: Oct 3, 2000
Filed: Oct 8, 1997
Inventor
David Atherton
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.