Minimum pipe wall thickness from ASME B31.1: t = P·D / (2·(SE + PY)) + c, with corrosion allowance c.
Formula
$$ t = \frac{P \cdot D}{2 (S \cdot E + P \cdot Y)} + c $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $P$ | Design pressure | N/mm² (from bar) | design |
| $D$ | Outside diameter | mm | pipe spec |
| $S$ | Allowable stress | N/mm² | ASME B31 material table |
| $E$ | Weld-joint efficiency (seamless = 1) | - | ASME B31 |
| $Y$ | Temperature coefficient | - | ASME B31 table |
| $c$ | Corrosion allowance | mm | service |
Sources
- ASME B31.1 Power Piping.
- ASME B31.3 Process Piping.