IP Library › Granted Patent US 4,856,592
Granted Patent Utility
US 4,856,592 · App. 07/134,628

Annulus cementing and washout systems for wells

Inventors: Bernard Herman Van Bilderbeek, Ian F. Milne
Patented Case View Patent ↗
Granted: Aug 15, 1989 Filed: Dec 16, 1987
Inventors
Bernard Herman Van Bilderbeek
Ian F. Milne
Assignee (at issue)
Plexus Ocean Systems Ltd.

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Quick Facts
Patent No.
US 4,856,592
App. No.
07/134,628
Filed
1987-12-16
Granted
1989-08-15
Kind
A