Shearing gate valve
CA 2012290 C · Owner: Hoang, Loc G. · Inventors: Baker, Gerald S.; Hoang, Loc G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A shearing type of gate valve having a sleeve of hard wear resistant material in the opening through the gate and coacting with an insert ring of hard, wear resistant material in one of the seat rings for shearing a wire line or tubular member extending through the valve and the gate the sleeve and insert, ring being assembled with the gate and the seat rings in a manner to provide sufficient compression preload thereon so that they are not subjected to tension loads which avoids chipping breaking or other damage to the sleeve and the insert rings. Preferably the sleeve and insert ring are of tungsten carbide. In two forms of the present invention an insert sleeve of hardened, wear …
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 March 15, 1990 and granted April 12, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 15, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 15, 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.