PETpla.net Insider 04 / 2015

PREFORM PRODUCTION 39 PET planet insider Vol. 16 No. 04/15  Type of cavity cooling: spiral or cascading with spiral cooling channels gaining popularity in recent years  Type of bubbler tube with newer designs featuring also spiral flow designs  Type of injection core pol- ishing: cores should be pol- ished in the axial direction rather than the radial one in order to support smooth material flow  Various injection core coat- ings have been tried with limited success  Cavities may be of one piece or may have a sepa- rate gate insert which may or may not have separate water cooling  Neck inserts should have a front taper that locks into the taper of the cavities and a back taper that locks it into the injection cores (Fig. 3.23) Your UV invisible protection our tailor-made UV blockers High Performance Liquid Colours and Additives repi.com crystal clear 300 to 400nm * This article was published in Bottles, Preforms and Closures, Ottmar Brandau, Chapter 3.7. Copyright Elsevier 2012 Please order your copy at the PETplanet insider book shop: https://www.petpla.net/books Bottles, Preforms and Closures A Design Guide for PET Packaging Second Edition by Ottmar Brandau € 115,00 180 pages © Copyright Elsevier 2012 Figure 3.23 The front taper (around the threads) transfers clamp tonnage, whereas the back taper assures align- ment with the injection core. (Picture courtesy of MHT-AG).