Pressure balanced inner chamber of a drilling head
CA 2113523 A1 · Owner: Campbell, John E. · Inventors: Campbell, John E.; Bailey, Thomas F.; Moeller, Larry F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system for maintaining an optimum pressure balance within an inner chamber of a drilling head for improved seal life and integrity. The system maintains a pressure differential across the seals thereby preventing well fluids from contaminating the seals and improving their useful life. The drive ring of a drilling head is rotatably supported by a series of bearings disposed within a bearing chamber. The secondary chamber of the drilling head is sealed to prevent contaminants from entering the chamber and fouling the seals. The seals withstand the borehole well pressures to prevent the introduction of contaminants by maintaining a, pressure differential across the seals. The present system …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed January 14, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 14, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 14, 2016.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.