API 5L X52
API 5L X52 material
Key Engineering Metrics
Instant specifications summary for API 5L X52
General Specifications & Standard Data
API 5LMinimum Design Metal Temperature rules for impact testing exemption under ASME B31.3 paragraph 323.2.2.
Mechanical Properties
Room Temp (20°C / 68°F)Allowable Stress Data (ASME B31.3 Table A-1)
asme-b31-3Allowable Stress vs Temperature
ASME B31.3 / BPVC Section II Part D Reference Curve
| Temperature (°C) | Allowable Stress (MPa) | % of Room Temp Rating |
|---|---|---|
| 38 | 137.9 | 100% |
| 93 | 137.9 | 100% |
| 149 | 137.9 | 100% |
| 204 | 137.9 | 100% |
| 260 | 137.9 | 100% |
| 316 | 135.0 | 98% |
| 343 | 131.0 | 95% |
| 371 | 125.0 | 91% |
| 399 | 117.0 | 85% |
| 427 | 105.0 | 76% |
🛡️ ASME B16.5 Flange P-T Ratings & Calculator
Material Group 1.1 (Carbon and low-alloy steel materials)
| Temp (°C) | Class 150 | Class 300 | Class 400 | Class 600 | Class 900 | Class 1500 | Class 2500 |
|---|---|---|---|---|---|---|---|
| -29 to 38 | 19.6 | 51.1 | 68.1 | 102.1 | 153.2 | 255.3 | 425.5 |
| 50 | 19.2 | 50.1 | 66.8 | 100.2 | 150.4 | 250.6 | 417.7 |
| 100 | 17.7 | 46.6 | 62.1 | 93.2 | 139.8 | 233 | 388.3 |
| 150 | 15.8 | 45.1 | 60.1 | 90.2 | 135.2 | 225.4 | 375.6 |
| 200 | 13.8 | 43.8 | 58.4 | 87.6 | 131.4 | 219 | 365 |
| 250 | 12.1 | 41.9 | 55.9 | 83.9 | 125.8 | 209.7 | 349.5 |
| 300 | 10.2 | 39.8 | 53.1 | 79.6 | 119.5 | 199.1 | 331.8 |
| 325 | 9.3 | 38.7 | 51.6 | 77.4 | 116.1 | 193.6 | 322.6 |
| 350 | 8.4 | 37.6 | 50.1 | 75.1 | 112.7 | 187.8 | 313 |
| 375 | 7.4 | 36.4 | 48.5 | 72.7 | 109.1 | 181.8 | 303.1 |
| 400 | 6.5 | 34.7 | 46.3 | 69.4 | 104.2 | 173.6 | 289.3 |
| 425 | 5.5 | 28.8 | 38.4 | 57.5 | 86.3 | 143.8 | 239.7 |
| 450 | 4.6 | 23 | 30.7 | 46 | 69 | 115 | 191.7 |
| 475 | 3.7 | 17.4 | 23.2 | 34.9 | 52.3 | 87.2 | 145.3 |
| 500 | 2.8 | 11.8 | 15.7 | 23.5 | 35.3 | 58.8 | 97.9 |
| 538 | 1.4 | 5.9 | 7.9 | 11.8 | 17.7 | 29.5 | 49.2 |
Working pressures are in gauge (bar). Values interpolated linearly for intermediate temperatures per ASME B16.5 para. 2.3.
Chemical Composition (% Weight)
Heat & Product Analysis🛡️ Service Compatibility
Primary material for high-pressure oil & gas transmission pipelines up to 232°C (450°F).
Standard for refined products, natural gas transmission, and NGL trunklines.
Requires NACE MR0175 / ISO 15156 Annex A compliance, controlled hardness ≤22 HRC, and HIC/SSC testing.
Suitable for steam up to 400°C. High yield strength allows thinner wall thickness.
PSL2 grade requires impact testing at -20°C or -40°C. Verify CVN toughness requirement.
Requires FBE coating, 3LPE/3LPP lining, or cathodic protection for subsea/marine service.
🔥 Welding & Heat Treatment
10°C min; 100°C (212°F) preheat recommended for t > 19mm or high restraint to prevent hydrogen-assisted cold cracking per API 1104 / ASME B31.8.
Not required for standard pipeline girth welds (t ≤ 19mm) unless specified for severe sour service (H2S hardness ≤22 HRC per NACE MR0175).
Mandatory Charpy V-notch impact testing for PSL2 pipe at -20°C or -40°C per API Spec 5L.
Material property data provided is for preliminary engineering reference. Always verify properties against the latest ASME BPVC Section II, ASTM material specification, and Material Test Report (MTR/MTC).