Granted Patent
Utility
US 4,757,935 · App. 06/923,336
Method and device for flushing the inside surface of a pipe in the vicinity of a welded seam
Inventor:
Siegfried Gügel
Patented Case
View Patent ↗
Granted: Jul 19, 1988
Filed: Oct 27, 1986
Inventor
Siegfried Gügel
Assignee (at issue)
Kraftwerk Union Aktiengesellschaft
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.