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:
Feb. 01, 2000
Filed:
Feb. 04, 1997
Applicant:
Inventor:
Ulrich Schulte, Kelkheim, DE;
Assignee:
Hoechst Aktiengesellschaft, , DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B29C / ;
U.S. Cl.
CPC ...
264558 ; 264560 ; 264150 ; 2642091 ; 264237 ; 425 71 ;
Abstract
The process according to the invention for producing large-bore thick-walled pipes made of polyethylene comprises extruding the polymer composition out of an annular die 3 and subsequently cooling the melt 7 emerging from the die 3 using water as the coolant from the outside, the melt 7 emerging from the die being additionally also cooled with water from the inside. In order to ensure the internal cooling, according to the invention floating plugs 11 and 12 are inserted, which plugs are fixed in their physical position relative to the extrusion die 3 by means of retaining elements.