Calculators
Tank Sizing & Inspection
Storage tank capacity (gross, max fill, net usable), product weight, hydrostatic head at max fill, and API 653 minimum shell thickness for a specific shell course using the 1-foot method. For vertical cylindrical atmospheric tanks per API 650 / API 653.
Method: Capacity by cross-sectional area (π/4 · D2) × fill height, converted using 7.48052 gal/ft3 and 42 gal/bbl. Hydrostatic head at max fill (psig) = H · SG · 0.433. API 653 1-foot method minimum thickness: tmin = 2.6 · D · (H − 1) · G / (S · E) + CA, where H is the design liquid level above the course under review, D is tank diameter in ft, S is allowable stress and E is joint efficiency. References: API Std 650 (New Tank Construction); API Std 653 §4.3 (In-Service Shell Inspection).
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