| 摘要 |
A method and apparatus for continuously extruding, biaxially orienting and forming molded products from a web of thermoplastic material and further, continuously separating the products from the web selvage, stacking and handling the products and recycling the web selvage for further extrusion. The method and apparatus use continuous molding devices, namely, multiple mold cavities in a rotating polygon configuration over the peripheral surface of which the biaxially oriented web is securely and continuously positioned by a follower roller interfacing the polygon with a biaxial orientation device. Continuous and immediate interfacing is effected to prevent loss of orientation in the web which is kept at a temperature suitable for ingestion thereof into the mold cavities by vacuum, pressure or plug assist. In one preferred embodiment the inertia at the interface between the undulating peripheral surface of the rotating mold polygon and the biaxial orientation apparatus is reduced to an optimal minimum.
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