IP Library › Granted Patent US 4,893,844
Granted Patent Utility
US 4,893,844 · App. 06/771,137

Tubular coupling with ventable seal

Inventors: K. Darrel Chelette, Charles A. Bollfrass
Patented Case View Patent ↗
Granted: Jan 16, 1990 Filed: Aug 28, 1985
Inventors
K. Darrel Chelette
Charles A. Bollfrass
Assignee (at issue)
Baker Hughes Holdings LLC

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Quick Facts
Patent No.
US 4,893,844
App. No.
06/771,137
Filed
1985-08-28
Granted
1990-01-16
Kind
A