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. 28, 1989
Filed:
Feb. 25, 1987
Yasuo Yamabe, Saitama, JP;
Sekisui Kagaku Kogyo Kabushiki Kaisha, Osaka, JP;
Abstract
A method for the production of a composite pipe with at least the inner surface thereof covered with a plastic layer, comprising: forming a coiled metal sheet into a cylinder, during the conveyance of the metal sheet, by a cylindrical inner mold and at least one of a plurality of outer molds lined up in the direction of conveyance of the metal sheet, said outer mold having a housing composed of two separatable parts and being fitted around said inner mold with a fixed space; joining the side edges in the circumferential direction of said cylinder together; and extruding molten resin into a cylindrical shape over the inner surface of the cylinder from the inner mold, resulting in a composite pipe the inner surface of which is covered with a plastic layer.