METHODS AND DEVICES FOR MANUFACTURING BIAXIALLY ORIENTED TUBING

摘要

A method for producing a biaxially oriented tube from thermoplastic material. A tube in preform condition is extruded from thermoplastic material using an extruder with an extruder die head having an inner die member forming a lumen in the tube in preform condition. A temperature conditioning is performed. Use is made of an expansion device having a nose end, which expansion device brings about expansion of the tempered tube in preform condition in circumferential direction. The method comprises drawing the tempered tube over the expansion device using a drawing device which is arranged downstream of the expansion device and acts on the tube, in such a manner that said tube is transformed from a tube in preform condition into a biaxially oriented tube with thermoplastic material which is oriented in axial direction and in circumferential direction of the tube, wherein said biaxially oriented tube is cooled. Use is made of one or more temperature sensors that sense the temperature of the tube in preform condition upstream of or at the nose end of the expansion device.