METHOD AND DEVICE FOR COOLING PIPE IN MAKING EXTRUSION THE SUCCESSIVE DISPERSIONS USING A LIQUID ON THE INSIDE WALL.

摘要

The invention provides an improved method and an improved device for cooling the inner surface of the wall of a plastic pipe during its manufacture by extrusion. The refrigerant is dispersed on the internal surface of the wall pr successive sprays at given time intervals. Advantageously, the refrigerant is dispersed by means of a system which moves inside the pipe following a motion of reciprocation. The injector may advantageously be equipped with means giving a rotating cone of dispersed droplets.