Arrangement and method for conducting substance and seal therefor
CA 2030191 C · Owner: Braddick, Britt Oliver · Inventors: Langer, Michael; Braddick, Britt Oliver
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A well bore operating string (OS) has upper (45) and lower (26) wipers thereon with the wipers releasably connected by a frangible member (81) for releasing the wipers (45), (26) in response to pressure in the operating string (OS). Seals (210), (211), (212) (214), (215), (216), (217) are provided to close off communication from the operating string bore to confine the pressure present in the operating string in a manner to assure release of the wipers as and when desired and in a sequence as may be desired. Upper (50) and lower (35) pump down plugs sealably seat respectively, in, the upper (45) and lower (26) wipers to form a movable mechanical barrier, to isolate or wipe ahead of and …
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 November 16, 1990 and granted November 4, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 16, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 16, 2012.
- 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.