Method of manufacture of pig iron
CA 2037834 A1 · Owner: Hoogovens Groep Bv · Inventors: Nijholt, Rienk M.; Molenaar, Ronald N.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In the manufacture of pig-iron in a shaft furnace, a taphole is closed with hardened plugging compound during making of the iron and is opened for the tapping of the iron and then resealed. The resealing of the taphole comprises inserting hardenable plugging compound into the taphole and before, hardening thereof, driving a hollow tube into the plugging compound. The hollow tube has an open front end. The tube is pulled out at the next tapping. The use of a tube avoids disturbance of the plugging compound and creates a smoother taphole leading to, improved flow of liquid iron.
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 8, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 8, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 8, 2013.
- 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.