____________ heads are the most economical choice for cylindrical vessels operating at high pressures (> 15 atm.)?
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Answer: C. Ellipsoidal
Explanation
Ellipsoidal heads provide a smooth transition that resists high internal pressure efficiently. They require thinner walls than flat plates while costing less to fabricate than hemispheres. This balance makes them the most economical choice for high-pressure cylindrical vessels. Pressure vessel design balances manufacturing costs against structural safety requirements. Standard 2:1 ellipsoidal heads provide optimal stress distribution for high-pressure service. Forming elliptical shapes is less expensive than stamping true hemispherical metal plates.
High-pressure chemical reactors and storage vessels frequently utilize 2:1 ellipsoidal heads. Selecting economical vessel heads reduces capital costs in large chemical plant construction projects. Vessel codes ensure that ellipsoidal closures safely contain pressures exceeding 15 atmospheres. Option A hemispherical heads are structurally superior but much more expensive to manufacture. Option B dished is a broad term, and standard torispherical heads are weaker at high pressures. Option D conical heads create high stress concentrations and are unsuitable for high pressures.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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