• Injection Stretch Blow Moulding

     

    Typical Materials Used

    Polyethylene - Terephthalate PET


    Typical Products Produced

    Carbonated and soft drink bottles Cooking oil containers
    Agrochemical containers Health and oral hygiene products
    Bathroom and toiletry products  
    Overview

    Injection stretch blow moulding is used for the production of high quality containers.
     

    The Process

    The process is divided in to four:
     
    Injection 
    Molten polymer flows into the injection cavity via the hot runner block, to produce the desired shape of the PREFORM with a mandrel (the core pin) producing the inner diameter and the injection cavity the outer. After a set time the injection moulds and core pins part and the preform held in a neck carrier is rotated 90º.

    Stretching and Blowing 
    Once conditioned to the correct temperature the preform is ready for STRETCHING and BLOWING to the finished shape. Once the preform is within the BLOWMOULD area the moulds close, a stretch rod is introduced to stretch the preform longitudinally and using two levels of air pressure, the preform is blown circumferentially.

    Discharge 
    After a set time for cooling the moulds open and the preform is removed via drop chutes or robotics. In practice the four stages are carried out concurrently using a revolving carousel of moulds.