Joining polyolefinic members by fusion
CA 1306091 C · Owner: British Gas Plc · Inventors: Dickinson, Alan John; Stafford, Trevor George
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Members especially hollow members 10, 12 such as pipes and pipe fittings, one member 12 being of, for example cross-linked, polyethylene and the other member 10 being of for example, medium density polyethylene are joined by fusion using a butt, fusion machine. End surfaces of the members are pressed at higher pressure against a hot plate 18 to upset only the medium density material to form beads 20, 22. No cross-linked material is upset to form beads. The pressure is reduced during a soak stage, then the plate is removed and the surfaces are mutually engaged at the higher pressure. The beads formed are adjacent the interface between the members and both beads are offset towards the medium …
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
- Granted August 11, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 11, 2009.
- 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.