How is the crown radius of a dished pressure vessel head typically estimated______________________?
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Answer: C. one
Explanation
Dished pressure vessel heads are manufactured in various geometries, including torispherical and ellipsoidal dished configurations. Standard design codes specify that the crown radius of a dished head should equal the inner diameter of the cylindrical shell. This dimensional relationship ensures smooth stress distribution across the knuckle and crown regions under internal pressure loading. Pressure vessel heads close the ends of cylindrical shells in boilers, storage tanks, and chemical reactors operating under high pressure. Torispherical heads feature a dish radius equal to the shell diameter and a smaller knuckle radius to minimize localized bending stresses. ASME boiler and pressure vessel codes provide strict geometric guidelines for calculating required wall thicknesses of dished heads.
Option A of one-fourth and option B of half would create severe geometric discontinuities and high stress concentrations in vessel heads. Option D of two and option E of three represent oversized crown radii that would alter the dished head profile incorrectly. Therefore, setting the crown radius equal to the diameter corresponds to a factor of one, making option C correct.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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