Granted Patent
Utility
US 6,730,876 · App. 09/866,258
Highly ductile reduced imperfection weld for ductile iron and method for producing same
Inventors:
Daniel A. Copeland, David J. Farr, James E. Wren
Patented Case
View Patent ↗
Granted: May 4, 2004
Filed: May 29, 2001
Inventors
Daniel A. Copeland
David J. Farr
James E. Wren
Assignee (at issue)
U.S. Pipe and Foundry 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.