Granted Patent
Utility
US 4,615,477 · App. 06/604,281
Method for replacing tubes in a header or drum
Inventors:
Ralph E. Spada, Thomas Shilot
Patented Case
View Patent ↗
Granted: Oct 7, 1986
Filed: Apr 27, 1984
Inventors
Ralph E. Spada
Thomas Shilot
Assignee (at issue)
The Babcock & Wilcox 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.