IP Library › Granted Patent US 4,846,442
Granted Patent Utility
US 4,846,442 · App. 07/143,666

Gate valve with lock ring

Inventors: Curtis W. Clarkson, Larry F. Koll
Patented Case View Patent ↗
Granted: Jul 11, 1989 Filed: Jan 14, 1988
Inventors
Curtis W. Clarkson
Larry F. Koll
Assignee (at issue)
The Clarkson Company

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Quick Facts
Patent No.
US 4,846,442
App. No.
07/143,666
Filed
1988-01-14
Granted
1989-07-11
Kind
A