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Barlow's Formula — Minimum Wall Thickness
Minimum wall thickness for internal pressure, from Barlow / ASME B31.3.
How it works
- t = (P × D) ÷ (2 × S × E)
- Pressure in bar → divide by 10 for MPa
- Add corrosion + mill tolerance after
Worked example
P 50 bar, D 114.3 mm, S 138 MPa, E 1 → t ≈ 2.07 mm.
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Reference tool — always validate against project specs. Not a substitute for a qualified engineer.