Method and apparatus for cooling in the manufacture of bioriented sheets from thermoplastics of high or medium molecular weight.

摘要

The invention relates to a high-performance method for cooling in the manufacture of bioriented sheets from thermoplastics of high or medium molecular weight operating with a long neck with an external cooling of the film bubble by means of a high-performance cooling ring, with an internal cooling system and also a calibrating cage, which is characterised in that the bubble neck is stabilised and guided shortly before its expansion by a conical trailing mandrel, which can be adjusted in height, and the highly intensive internal cooling becomes effective immediately after this trailing mandrel in the expanding region of the film bubble. …The invention also relates to an apparatus for carrying out this method, which is characterised in that it has a tube which is fitted on a die, the said tube having arranged inside it an inner tube, which is introduced into the die and is in connection with a suction tube, a conical trailing mandrel arranged around the outer tube and an end suction tube provided with die lips. ……