IP Library › Granted Patent US 5,213,158
Granted Patent Utility
US 5,213,158 · App. 07/811,553

Dual rotating stripper rubber drilling head

Inventors: Thomas F. Bailey, John E. Campbell
Patented Case View Patent ↗
Granted: May 25, 1993 Filed: Dec 20, 1991
Inventors
Thomas F. Bailey
John E. Campbell
Assignee (at issue)
Masx Energy Services Group, Inc.

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Quick Facts
Patent No.
US 5,213,158
App. No.
07/811,553
Filed
1991-12-20
Granted
1993-05-25
Kind
A