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:
Apr. 29, 1980
Filed:
Aug. 29, 1977
Sekisui Kagaku Kogyo Kabushiki Kaisha, Osaka, JP;
Abstract
A method for continuously producing a reinforced plastic pipe includes helically winding an endless belt on a rotating mandrel, continuously winding a molding material impregnated with a thermosetting resin on the endless belt, continuously moving the molding material toward the tip of the mandrel together with the endless belt by the rotation of the mandrel, passing the moving molding material through a curing zone to cure the thermosetting resin, and then removing the molding material from the endless belt at the tip portion of the mandrel. Prior to the introduction of the molding material into the curing zone, a split ring mold having an inside surface of a desired shape is mounted around the molding material so as to clamp the molding material tightly, thereby to convert the shape of the outside surface of the molding material into one corresponding to the shape of the inside surface of the split ring mold. After the molding material leaves the curing zone, the split ring mold is removed from the molding material, and that portion of the molding material on which the mold had been mounted is severed to provide a reinforced plastic pipe having a spigot element of a desired outside diameter and a desired outside surface shape.