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:
Mar. 19, 2002
Filed:
Mar. 22, 1999
Bernard Prevotat, Le Chesnay, FR;
Jean-Jacques Acket, Challuy, FR;
Alphacan, , FR;
Abstract
The invention concerns a method for treating plastic tubes, in particular PCV tubes, obtained by extrusion, whereby a tube is brought to a molecular orientation temperature, higher than room temperature, and is subjected to bi-axial drawing by radial expansion and axial elongation, to obtain a bi-oriented tube whose mechanical properties are improved. The tube (T) is cut into elements ( ) of predetermined length immediately after being extruded and its temperature is higher than the molecular orientation temperature, each element constituting a blank ( ); each blank ( ) is placed in a chamber (E) to be cooled therein by a fluid (F) to a temperature close to the molecular orientation temperature, the dwell time of the blank in the chamber being greater than the time of its production by extrusion; and the blank ( ) is then extracted from the chamber (E) to be subjected to a treatment enabling its bi-orientation.