A method, an apparatus and an extrusion die of producing by extrusion electroweldable pipe sockets and electroweldable fittings of thermoplastic materials thereby using a first pipe part formed in a first extruder

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Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

• Filed September 25, 1987 and granted August 8, 1990. A European patent lasts at most 20 years from filing, so its term ended September 25, 2007.
• A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by March 25, 2013.
• We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.