Granted Patent
Utility
US 5,238,331 · App. 07/905,750
Modularized machine for reconditioning pipelines
Inventor:
Gordon R. Chapman
Patented Case
View Patent ↗
Granted: Aug 24, 1993
Filed: Jun 29, 1992
Inventor
Gordon R. Chapman
Assignee (at issue)
CRC-Evans Rehabilitation Systems, Inc.
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.