IP Library › Granted Patent US 4,847,222
Granted Patent Utility
US 4,847,222 · App. 07/046,238

Basic refractory shapes

Inventors: Richard J. Knauss, David J. Michael
Patented Case View Patent ↗
Granted: Jul 11, 1989 Filed: May 4, 1987
Inventors
Richard J. Knauss
David J. Michael
Assignee (at issue)
Dresser Industries, Inc.

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Quick Facts
Patent No.
US 4,847,222
App. No.
07/046,238
Filed
1987-05-04
Granted
1989-07-11
Kind
A