Rotating bop and method
CA 2259680 C · Owner: Weatherford/Lamb, Inc. · Inventors: Grayson, Michael B.; Hosie, David G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A rotating blowout preventer and method is disclosed that includes a flexible bladder that defines a pressure chamber radially outwardly of the bladder for direct activation of the bladder to allow for gas tight sealing along the variable profile of drill pipe and the irregular shape of the kelly. The pressure chamber for activating the bladder is preferably defined within the rotating seal assembly. As well the rotating seal assembly includes both the bladder and the bearings. A pressure drop element is included within the hydraulic flow line through the rotating seal assembly so that the upper seal and bearing have a significantly reduced pressure drop for increased lifetime operation. …
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 18, 1999 and granted August 13, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 18, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 18, 2021.
- 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.