Plastic packing ring or disk and a method and apparatus for making same
CA 2062159 A1 · Owner: Piotrowitz, Juergen · Inventors: Gerhard Kopp G.M.B.H.; Piotrowitz, Juergen
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A plastic packing ring or disk for scrapers and other such bodies sliding in pipelines consists essentially of polyurethane and is supported annularly on the inside of the pipe. To make especially this kind of support elements on scrapers more resistant to friction stresses and improve their sliding qualities the, plastic packing rings or disks on the scrapers have embedded particles of solidified polyethylene at least in an outer part intended for contact with the pipeline.
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 2, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 2, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 2, 2014.
- 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.