Granted Patent
Utility
US 5,975,754 · App. 09/220,708
Method for monitoring the wear and extending the life of blast furnace refractory lining
Inventors:
Richard J. Groth, Yongfu Zhao
Patented Case
View Patent ↗
Granted: Nov 2, 1999
Filed: Dec 24, 1998
Inventors
Richard J. Groth
Yongfu Zhao
Assignee (at issue)
USX 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.