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. 27, 1990
Filed:
Sep. 15, 1988
Serge Nadeau, Montreal, CA;
Northern Telecom Limited, Montreal, CA;
Abstract
Making jacketed pipe using metal strip coated with a plastic coating compatible with the jacket material. After the strip is formed into tube by turning over longitudinal edges of the strip, the jacketing material is then extruded onto the tube under an extrusion pressure insufficient to cause tube collapse. This is conveniently done by the known 'tubing' process. Subsequent to the extrusion step, the jacket material is subjected to radial inward pressure also insufficient to cause tube collapse. This pressure reduces the outside diameter of the jacket and presses it against the coating on the tube. The inward pressure step is performed while residual heat from extrusion remains at the inner surface of the jacket to fuse the jacket to the plastic coating. Inward pressure is preferably applied by a polishing die.