| 摘要 |
PURPOSE:To manufacture a hollow material of uniform thickness of wall of a molded material by overlappingly disposing a plurality of parisons of different diameter, feeding pressurized fluid to a parison located inside and applying the pressurized material to a parison located outside through said inner parison. CONSTITUTION:An outer parison 18b larger than an inner parison is disposed in the main body section 10a of large outer dimension of a hollow material 10, while an inner parison 18a of small diameter is disposed on a duct section 10b of small outer dimension, respectively corresponding with. When compressed air as pressurized fluid is fed from a blowing port 22, the inner parison 18a is expanded as the end separated from the blowing port 22 is sealed. The outer parison 18b is pressed by the compressed air fed through an opening 26 of the inner parison 18a and adhered to the inner surface related to a molding die 20. Stretching ratio of respective parisons, therefore, are made almost uniform, and a molded material of given wall thickness can be molded. |
