Continuous prodn. of plastics tubing - with varying diameter and wall thickness

摘要

The process consists of halting the draw-off carriage of the extruder for fixed time intervals. A conventional timer gives signals for stopping carriage, increasing the shaping air pressure of tube and actuating a conventional brake or the motor which drives carriage. A second timer gives signals for re-starting carriage and an electro-valve operates on the entry pipes.