Tank Shell Thickness Calculator

Estimate shell thickness using pressure and material limits. Compare corrosion allowance and efficiency effects quickly. Export results, study trends, and support practical construction decisions.

Enter Design Data

Design Pressure (MPa)

Liquid Density (kg/m³)

Liquid Height (m)

Tank Diameter (mm)

Allowable Stress (MPa)

Joint Efficiency (%)

Corrosion Allowance (mm)

Mill Tolerance (%)

Plate Increment (mm)

Shell Material Density (kg/m³)

Example Data Table

Parameter	Example Value	Unit
Design Pressure	0.60	MPa
Liquid Density	1000	kg/m³
Liquid Height	12	m
Tank Diameter	3000	mm
Allowable Stress	138	MPa
Joint Efficiency	85	%
Corrosion Allowance	1.5	mm
Mill Tolerance	12.5	%
Plate Increment	1.0	mm
Material Density	7850	kg/m³

Formula Used

Hydrostatic head pressure
P_head = (ρ × g × h) / 1,000,000

Total design pressure
P_total = P_design + P_head

Required shell thickness before corrosion allowance
t = (P_total × D) / (2 × S × E − 1.2 × P_total)

Required thickness with corrosion allowance
t_req = t + CA

Nominal thickness before plate rounding
t_nom = t_req / (1 − mill tolerance)

MAWP based on selected plate
MAWP = (2 × S × E × t_net) / (D + 1.2 × t_net)

Where P is pressure in MPa, D is diameter in mm, S is allowable stress in MPa, E is joint efficiency, and CA is corrosion allowance in mm.

How to Use This Calculator

Enter the tank design pressure in MPa.
Provide stored liquid density and liquid height for hydrostatic head.
Enter tank diameter, allowable stress, and weld joint efficiency.
Add corrosion allowance and mill tolerance values.
Set a plate increment for practical plate selection.
Click the calculate button to display results above the form.
Review the recommended thickness, MAWP, and trend graph.
Download the result as CSV or PDF for project records.

Frequently Asked Questions

1. What does this calculator estimate?

It estimates cylindrical tank shell thickness using pressure, hydrostatic head, allowable stress, joint efficiency, corrosion allowance, and mill tolerance.

2. Why is hydrostatic head included?

Stored liquid adds pressure at the shell. Taller liquid height and greater density increase the total pressure that the shell must resist.

3. What is joint efficiency?

Joint efficiency reflects weld quality and examination level. Lower efficiency reduces allowable capacity and usually increases required shell thickness.

4. Why add corrosion allowance?

Corrosion allowance reserves extra thickness for expected future material loss. It helps the shell remain safe through service life.

5. What does mill tolerance do?

Mill tolerance accounts for permitted plate thickness variation from production. The nominal thickness is increased so the minimum delivered plate still meets demand.

6. What is MAWP in this result?

MAWP is the maximum allowable working pressure supported by the recommended plate after efficiency, corrosion allowance, and mill tolerance effects are considered.

7. Can this replace code-based design checks?

No. It is a practical sizing tool. Final design must follow the applicable standard, project specification, and qualified engineering review.

8. Why is the recommended thickness rounded up?

Plate is usually purchased in standard increments. Rounding up gives a more buildable thickness for procurement and fabrication planning.