Seal structure for elevated temperature service
CA 2030206 C · Owner: Kyker, G. Stephen · Inventors: Alvarez, Eduardo; Kyker, G. Stephen; Irby, Richard E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A seal comprises a sandwich of a soft low modulus, resinous layer between two outer layers of harder high, modulus resinous material to provide an effective high pressure seal at both low and high temperatures. The seal can be used in well head service, e.g. in-a blowout preventer or stuffing box seal in oil wells, geothermal wells or hydraulic mining pipes. The high modulus material is preferably a polybenzimidazole containing 5 to 50 wt.% short fibers. The low modulus material is preferably a thermoplastic fluorinated hydrocarbon polymer or a fluorinated synthetic elastomer containing polybenzimidazole in powder and/or short fiber form and short fibers of glass and/or carbon. For blowout …
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 April 5, 1994. 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.