Engineering calculation suite

Storage Tank Minimum Thickness Calculator

API 650 Atmospheric Storage • API 620 Low-Pressure • ASTM reference framework

Project information

Tank tag / numberDescriptionProjectLocation

Tank code

Design conditions

Unit systemDesign pressure(0 for API 650; psig or MPa for API 620)Tank diameter(ft or m)Design liquid level(in or mm)Specific gravity(of stored liquid)Design temperature(°F or °C)Corrosion allowance(in or mm)

Material & joint

Material specificationAllowable stress S(psi or MPa)Joint efficiency E

Calculation report

T-301

Atmospheric storage tank

Required shell thickness

3.061 in

Net shell thickness

2.936 in

One-foot / pressure basis

2.936 in

Design liquid height

480 in

Governing case: API 650 one-foot method (course 1). Corrosion allowance of 0.125 in included.

Detailed results

Course 1 design basis: 2.936 in

Net required (governing): 2.936 in

Total required (incl. CA): 3.061 in

Design liquid level: 480 in

Standards basis

API 650Welded Tanks for Oil Storage — shell thickness (one-foot method)

API 620Design & Construction of Large, Welded, Low-Pressure Storage Tanks

API 653Tank Inspection, Repair, Alteration, and Reconstruction (in-service)

API 650 Section 5.6Shell design — one-foot method course thickness

API 620 Section 5.10Shell design — internal pressure + hydrostatic

AWWA D100Welded Carbon Steel Tanks for Water Storage (reference)

ASME BPVC II-DAllowable stress values for plate materials

ASTM A516 / ASME SA-516Carbon-steel pressure-vessel plate reference

ASTM A240 / ASME SA-240Stainless-steel plate reference

API 650 Table 5.2Allowable stress for shell plate materials

AI Engineering Advisor

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