Vessel supports: a vertical storage vessel is never supported by which type of support?

Introduction / Context:
Mechanical design of pressure and storage vessels uses standard support types selected primarily by vessel orientation and geometry. Correct support selection ensures stability, manageable stresses, and safe load transfer to foundations.

Given Data / Assumptions:

• Vessel orientation: vertical storage vessel (cylindrical).
• Conventional support options: skirt, lugs/legs, brackets, saddles.

Concept / Approach:
Saddle supports are specifically intended for horizontal cylindrical vessels to cradle the shell and distribute loads. Vertical vessels commonly use a skirt (for large/heavy vessels) or lugs/legs/brackets (for smaller vessels) to carry weight and lateral loads (wind, seismic). Hence, “saddle support” is not used for vertical vessels.

Step-by-Step Solution:

Verification / Alternative check:
Standard references and codes consistently depict vertical vessels with skirts or legs/lugs and horizontal vessels with two saddles.

Why Other Options Are Wrong:

• Bracket, lug, legs with baseplate: used for smaller vertical vessels.
• Skirt: the most common for tall/heavy vertical vessels; resists wind/seismic moments.

Common Pitfalls:
Assuming a single universal support; ignoring overturning moments from wind or seismic that often dictate the need for a skirt.

Final Answer:
Saddle support