Blow moulding

    Blow moulding technology is based on air blowing into a plastic tube with 0.5 to 2 mm wall thickness (in order to enlarge its size 2 to 5 times) which is drawn through a take off device (in order to achieve up to 5-fold elongation). The blown film with a 0.015 to 0.3 mm normal wall thickness is then cooled and wound. LDPE, HDPE, PP, PVC, PA and PET films are made by blow moulding. Multi-layer films with various material compositions are also made by blow moulding. The films can have up to seven layers. The design of extrusion heads for multi-layer films is very complicated and their use to produce film requires strict compliance with the production procedure