PETpla.net Insider 10 / 2011

PREFORM PRODUCTION 19 PET planet insider Vol. 12 PETplanet print Vol. 6: The Rapid Guide to Perfect Preforms by Rick Unterlander and Ottmar Brandau fax: +49 (0) 6221-65108-28 [email protected] www.petpla.net Order your copy now! 1- 3 exemplar each 129,- € 4 - 10 exemplar each 99,- € > 10 exemplar each 69,- € prices in EUR + VAT. to open the valve stems properly. Typical pressures are in the range of 8 to 10bar (120 – 145psi). 7. Check that the valve gate open timing is adjusted properly. This is typically 0sec. Minimize to allow more time to open. 8. Check all temperature readings and adjust higher if necessary. PET resin should be melted at about 280ºC (536ºF) +/- 10ºC (18ºF). Increase if necessary. 9. Check that transition position is set to about 13% of shotsize and cushion. Higher values may result in under- filling. 10. Ensure the mould neck insert and lock ring vents are clean. This will minimize gas entrap- ment at the neck finish. 11. Check to ensure that no moisture exists on the moulding surfaces, either from water leaks or condensation. This may obstruct normal melt flow and cause filling problems. The environmental dewpoint should be below the chilled water tempera- ture to eliminate the risk of condensation. 12. Check hardware for worn, damaged or failed components, specifically the mould neck inserts (collapsed vents), lock ring vents, valve stems, valve stem seals, nozzle tips, shut-off nozzle plunger alignment, shooting pot motion, and extruder screw check valve leakage (single-stage machine only). www.petpla.net PET planet print vol.6 The Rapid Guide to Perfect Preforms machine no./name