Inflating a polymer tube or parison to manufacture hollow plastic goods is known as the _______________ procedure?
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Answer: A. Blow moulding
Explanation
Blow moulding involves inflating a heated thermoplastic tube inside a split mold cavity. Internal air pressure forces the softened parison outward against the cold mold walls to shape hollow items. This manufacturing technique is the industry standard for producing plastic bottles and hollow containers. The extruded plastic tube is known as a parison in industrial blow moulding operations. Thermoplastic materials soften predictably when heated allowing them to be stretched and inflated. Mold cooling solidifies the inflated plastic part rapidly before ejection from the machine.
Packaging industries utilize extrusion blow moulding to produce millions of plastic beverage containers daily. Automotive fuel tanks are manufactured using specialized high-volume blow moulding production lines. Designing uniform parison wall thickness ensures consistent structural strength in finished hollow products. Calendaring passes polymer melts through heated rollers to produce continuous plastic sheets and films. Extrusion forces melted polymer through shaped dies to create continuous profiles like pipes and rods. Injection moulding forces molten plastic into closed metal molds to produce solid precision components.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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