Transfer mandrel cooling newly-molded PET bottle preforms, directs airflow against internal base, to return along sides of bottle to constriction enhancing thread-region cooling

摘要

Transfer mandrel directs airflow against internal base, to return along sides of bottle to constriction enhancing thread-region cooling. Compressed cooling air is passed from the central channel (7) through the outlet (8) to the internal base (9) of the preform (3). It continues along the annulus (10) between mandrel and preform. At the end of the annulus near the preform external thread (11), the channel constricts (12) before the air leaves via the suction channel (4). In the region of constriction, flow velocity is caused to increase, reducing the internal pressure in comparison with that surrounding the preform.