API 5L X60 Pipe Calculator
ASME B31.8 — design pressure, minimum wall thickness and MAOP. SMYS is locked to the grade value.
API 5L X60 provides a minimum yield of 415 MPa (60 ksi) in seamless and LSAW forms. It is used for onshore and offshore transmission pipelines requiring higher design pressure than X52 allows.
When to use this calculator: Determine MAOP or required wall thickness for onshore and offshore X60 transmission lines using ASME B31.8 location class factors.
Example (API 5L X60)
| OD (mm) | Wall (mm) | Result |
|---|---|---|
| 406.4 | 9.53 | 14.0 MPa | 140 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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