IP Library › Granted Patent US 4,726,432
Granted Patent Utility
US 4,726,432 · App. 07/072,315

Differentially hardfaced rock bit

Inventors: Danny E. Scott, Eric C. Sullivan
Patented Case View Patent ↗
Granted: Feb 23, 1988 Filed: Jul 13, 1987
Inventors
Danny E. Scott
Eric C. Sullivan
Assignee (at issue)
Hughes Tool Company - USA

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Quick Facts
Patent No.
US 4,726,432
App. No.
07/072,315
Filed
1987-07-13
Granted
1988-02-23
Kind
A