API 5L X52 Pipe Calculator
ASME B31.8 — design pressure, minimum wall thickness and MAOP. SMYS is locked to the grade value.
API 5L X52 has a minimum yield of 360 MPa (52 ksi) and is available in seamless, ERW, and LSAW forms to API 5L PSL1 and PSL2. It is widely used for onshore transmission pipelines at moderate design pressures.
When to use this calculator: Calculate minimum wall or design pressure for onshore transmission pipelines and compare PSL1 versus PSL2 design requirements.
Example (API 5L X52)
| OD (mm) | Wall (mm) | Result |
|---|---|---|
| 323.9 | 9.53 | 15.3 MPa | 153 bar design pressure (F=0.72) |
Results are reference values — verify against API TR 5C3 (OCTG) or ASME B31.8 (line pipe) before use in final design.
Design Pressure
P = (2 × t × SMYS × F × E × T) / OD | ASME B31.8 §841.11
E = 1.0 (seamless / full-NDE ERW / LSAW), T = 1.0 (≤120 °C). Adjust per B31.8 Tables 841.115A/B for temperature derating or reduced joint efficiency.
Minimum Wall Thickness
t = (P × OD) / (2 × SMYS × F × E × T) | Rearranged ASME B31.8
Maximum Allowable Operating Pressure (MAOP)
MAOP = (2 × t_actual × SMYS × F × E × T) / OD
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