High-yield pipeline steel grades — A694 & API 5L
High-yield carbon steels are micro-alloyed carbon–manganese steels made for high-pressure transmission pipelines. The number in the grade is the minimum yield strength in ksi: F52 and X52 mean 52 000 psi (360 MPa).
What high-yield carbon steel is
Flanges and fittings on a pipeline are matched to the line pipe: ASTM A694 forgings for flanges, MSS SP-75 WPHY fittings, and API 5L line pipe. Matching the yield strength lets the fitting be welded to the pipe without a thickness or strength mismatch.
- Carbon 0.26 % max with manganese up to 1.60 %
- Micro-alloyed with niobium, vanadium or titanium for strength
- Normalised or quenched and tempered
- Carbon-equivalent limits for field weldability
Key properties
| A694 F52 / API 5L X52 yield, min | 360 MPa |
|---|---|
| A694 F60 / X60 yield, min | 415 MPa |
| A694 F65 / X65 yield, min | 450 MPa |
| A694 F70 / X70 yield, min | 485 MPa |
| Typical test | Charpy at project temperature, hardness for sour service |
High-yield carbon steel grades compared
Chemistry and minimum room-temperature properties from the governing ASTM / ASME / API specifications. Open any grade for its full data sheet and PDF.
| Grade | Form | UNS | Cr% | Ni% | Mo% | C% | YieldMPa min | TensileMPa min |
|---|---|---|---|---|---|---|---|---|
| ASTM A694 F52 | High-yield forged flanges & fittings | K03014 | — | — | — | 0.30 max | 360 | 455 |
| ASTM A694 F60 | High-yield forged flanges & fittings | K03014 | — | — | — | 0.30 max | 415 | 515 |
| ASTM A694 F65 | High-yield forged flanges & fittings | K03014 | — | — | — | 0.30 max | 450 | 530 |
| ASTM A694 F70 | High-yield forged flanges & fittings | K03014 | — | — | — | 0.30 max | 485 | 565 |
| API 5L X52 PSL2 | Seamless line pipe | — | — | — | — | 0.24 max (N), 0.18 max (Q) | 360 | 460 |
| API 5L X60 PSL2 | Seamless line pipe | — | — | — | — | 0.24 max (N), 0.18 max (Q) | 415 | 520 |
| API 5L X65 PSL2 | Seamless line pipe | — | — | — | — | 0.18 max | 450 | 535 |
Reference information compiled from the published standard for convenience. It does not replace the current edition of the governing standard, which takes precedence. Verify critical dimensions and properties before design, purchase or fabrication. Teshi Engineers & Sales Promoters (P) Ltd accepts no liability for errors or omissions.
Specifications by product form
| Product form | Grades |
|---|---|
| High-yield forged flanges & fittings | ASTM A694 F52, ASTM A694 F60, ASTM A694 F65, ASTM A694 F70 |
| Seamless line pipe | API 5L X52 PSL2, API 5L X60 PSL2, API 5L X65 PSL2 |
Where high-yield carbon steel is used
- Oil and gas transmission pipelines
- Pig launchers and receivers
- Compressor and metering stations
- Offshore risers and subsea tie-ins
Welding and fabrication
Yield strength, not tensile, governs the match between flange and pipe. Specify the weld-end bore and thickness to suit the line pipe, and confirm carbon equivalent for field welding. Sour-service orders add HIC/SSC testing and hardness limits.
FAQ
High-yield carbon steel: common questions
What does F52 mean in ASTM A694?
F52 is the grade with a minimum yield strength of 52 ksi (360 MPa). It is the usual flange grade for X52 line pipe.
Which flange goes with API 5L X65 pipe?
An ASTM A694 F65 weld neck flange, with the bore and weld-end thickness machined to match the pipe.
Is A694 a pressure-vessel grade?
A694 covers forged flanges, fittings and valves for high-pressure transmission service; it is used under ASME B31.4 and B31.8 pipeline codes.
High-yield products from Teshi Group
ASTM A694 F42–F70 High-Yield Flanges
Grades, sizes and standards we supply
ViewMaterial productsCarbon Steel, Low-Temperature & High-Yield Pipeline Flanges
Grades, sizes and standards we supply
ViewOEM manufacturerIndustrial Flanges
ViewOEM manufacturerButt Weld Fittings
ViewStockist & supplierIndustrial Pipes
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