Thermoplastics corrugated tube

摘要

Tube is corrugated by a tool and a pressure medium. The known hollow strand from the extruder thus runs through a stationary tool formed of at least and shaping clamps which open and close to form each corrugation. The tool is immediately after the extruder nozzle. The clamps close for the time to form a wave peak and the tube is then pressed against a gauging mandrel to form the trough. While the clamps are closed they support the tube, and are then supported by an air pulse against the inside of the wave piece being formed. Draw-off is during the sliding movement of the clamps; the tube is pulled off from the extruder at a speed which varies as a half sine wave, whose max. corresponds to the extrusion speed, while the clamps are open.