PERFECCIONAMIENTOS INTRODUCIDOS EN UN APARATO PARA FABRICARUN CILINDRO FLEXIBLE A PARTIR DE UN MATERIAL EN BANDA CONTI-NUA DE MULTIPLES CAPAS.

摘要

Three-ply web material is rolled approximately 360 DEG into the form of a cylinder within a preform cavity. A feed roller at the opening rotates continuously and a spring loaded pressure plate has an edge at the opening which forces the web material against the feed roller. After the trailing edge of the segment of web material has passed the edge of the pressure plate, contact between feed roller and web material is lost and the circumferential position of the seam of the preform is thus precisely located. There is a slight overlap between the ends of the material at the same. The preform is longitudinally transferred into a non-conducting cylindrical forming cavity where heat and pressure are applied to fuse the overlap and form the seam. Heat is applied by induction heating through the walls of the forming cavity to the aluminum ply at only the overlap area. Pressure is applied by an expandable balloon mandrel inside the preform.