The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 23, 1978
Filed:
Dec. 03, 1975
Fritz Reich, Uhwiesen, CH;
Georg Fischer A.G., Schaffhausen, CH;
Abstract
A welding method for joining self-supporting structures made of thermoplastics by assembling said structures to form an area of mutual overlap, generating heat in said area to produce a welding zone having an elevated temperature and containing said thermoplastics in an at least plastic state for mutual coalescence of said structures in said area; an expanding agent is provided in the welding zone to generate a gas pressure therein for promoting coalescence of the weld. The invention is particularly suitable for welding tubes and other pipeline elements, such as fittings or sleeves, of thermoplastics and produces a tumescent weld which fills any macroscopic voids while including a plurality of minute closed cell voids.