Blow stretch

Typical bottle of water made of PLA obtained by blow stretch moulding (Courtesy of Acqua Sant Anna SpA). [Pg.324]

With the extrusion blow stretch process, the parison is shaped and temperature-conditioned in a preform cavity in the same way a bottle is extrusion blow-molded. From this preform cavity, the parison is transferred to the bottle cavity where a rod and air pressure combine to stretch and expand the resin. PVC is most oft n stretch blow-molded with this process. Although the one-step method is the most common (see Fig. 39), a two-step technique, in the same fashion as the others, is feasible. [Pg.840]

In stretch blow moulding process, the preform is stretched in both hoop direction and the axial direction as it is blown into Ae mould. Air blow with stretch rod create the final product by stretching the preform to the mould cavity. Injection stretch blow moulding process has two different blowing stages which are pre-blow and final blow. Stretch rod comes to the end of the bottle cavity with preblow assistance. The time in between stretch rod touches the preform and reaches the end of the cavity is crucial in order to get desired stretch ratio. These two points are named point 0 and point 10. Final blow is applied for the rest of the blowing process right after preblow. [Pg.1220]

Injection stretch-blow molding may be performed on a single one-stage machine in sequence or on two independent sequential two-stage machines. PET carbonated beverage botties are usually produced by injection stretch blow molding. [Pg.455]

Soft-drink bottles made from poly(ethylene terephthalate) (PET) are usuady made by stretch-blow mol ding in a two-step process. Eirst, a test-tube-shaped preform is molded, which is then reheated to just above its glass-transition temperature, stretched, and blown. Stretching the PET produces biaxial orientation, which improves transparency, strength, and toughness of the botde (54,56). A one-step process is used for many custom containers that are injection stretch-blow molded. [Pg.143]

Fig. 4.25 Extrusion stretch blow moulding Injection Stretch Blow Moulding...

Let us see what it means to search for an explanation. Consider a child blowing up a balloon. As he blows into the balloon again and again it expands and it becomes harder. Evidently the gas is pushing on the inside of the balloon, stretching its elastic walls. Why does the gas push... [Pg.5]

Standard Extrusion Blow-molding 2-Parison Head 4-Fold Stretch Blow Molding PVC (2) Single-parison Heads 4-Fold Stretch Blow Molding PET... [Pg.490]

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...