Granted Patent
Utility
US 6,038,725 · App. 08/624,184
Unicast paraffin removing pipeline pig incorporating multiple diameter and thickness discs and having a central bending portion for turns
Inventor:
Kenneth M. Knapp
Patented Case
View Patent ↗
Granted: Mar 21, 2000
Filed: Mar 29, 1996
Inventor
Kenneth M. Knapp
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.