Stretch-blowing

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. 

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. 

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

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

Figure 14.4 Schematic diagram of stretch blow molding ...

How is orientation introduced into an injection blow molded part Compare this to orientation in a stretch blow part ... 

Injection-production wells, in soil and ground water treatment, 25 835 Injection stretch blow molding, of food packaging, 18 50-51 Injection wells, 18 613... 

Injection stretch blow moulding in which all the operations are performed on the same line. The preform is stretched with a stretch rod . Stretching improves the mechanical performances and allows the production of thinner walled bottles. 

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