Plastics manufacturing — which statements about common processes are correct? Select the best combined option.
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APlastic bottles are made by the blowing process
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BPlastic sheets are made by calendering between rollers
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CApplying thermosetting resins to paper sheets is called laminating
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DPlacing raw material in moulds to shape articles is called moulding
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EAll of the above
Answer
Correct Answer: All of the above
Explanation
Introduction / Context:Industrial plastic forming relies on several foundational processes. This question validates whether you can identify which statements correctly map processes to products and methods.
Given Data / Assumptions:
- Focus on blow moulding, calendering, laminating, and moulding.
- Common, introductory-level manufacturing knowledge is assumed.
- No specialized variants (e.g., stretch-blow, twin-screw compounding) are needed.
Concept / Approach:Each listed process has a canonical application: blow moulding for hollow articles like bottles; calendering for continuous sheets/films; laminating for resin-bonded composites (paper or fabric); and moulding as the general method of shaping in a cavity.
Step-by-Step Solution:
1) Blowing: Expands heated plastic parison/preform against a mould cavity to form bottles and containers.2) Calendering: Passes softened plastic through rollers to produce sheets/films of controlled thickness.3) Laminating: Impregnates or coats sheets (e.g., paper) with thermoset resin, then cures under heat/pressure.4) Moulding: Encompasses compression, injection, transfer, etc., where raw material is shaped in a mould.Verification / Alternative check:Basic manufacturing texts and polymer processing guides match these definitions and typical applications.
Why Other Options Are Wrong:Individual process statements are correct but incomplete; the aggregate correctness is captured by “All of the above.”
Common Pitfalls:Confusing calendering with extrusion casting; forgetting that blow moulding specifically targets hollow shapes.
Final Answer:All of the above