Steel X60MS
Grade
ASTM API 5L X60 · GB L415
Specify for wet H₂S (sour) gas/oil lines: very low S, Ca inclusion shape control, HIC/SSC tested, hardness capped for NACE MR0175 compliance.
Values for the X60MS condition
Other X60 tempers and conditions
X60 is listed in 7 conditions; see the grade overview at X60.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
PSL2 sour service, normalized | Normalized sour-service option, typically for seamless sour gathering lines where TMCP plate route is not available. | 455 | 555 | 28 | 178 HB | 9.5 % IACS |
PSL2, normalized / normalizing-rolled | Pick for seamless or heavier-wall pipe where uniform fine-grained ferrite-pearlite and good weldability are needed without TMCP capability. | 460 | 560 | 28 | 175 HB | — |
X60MSThis page PSL2 sour service, thermomechanically rolled | Specify for wet H₂S (sour) gas/oil lines: very low S, Ca inclusion shape control, HIC/SSC tested, hardness capped for NACE MR0175 compliance. | 460 | 555 | 31 | 172 HB | 9.5 % IACS |
X60MDefault PSL2, thermomechanically rolled / TMCP | Default choice for modern welded (LSAW/HSAW/ERW) transmission pipe: lowest carbon equivalent, best low-temperature toughness and field weldability. | 465 | 560 | 30 | 172 HB | — |
API 5L X60 PSL1 | Lowest-cost X60 for non-critical gathering/water/structural lines where no upper strength cap, CVN or carbon-equivalent limit is required. | 470 | 565 | 26 | 180 HB | 9.5 % IACS |
PSL2 sour service, quenched and tempered | Heavy-wall sour-service pipe, bends and fittings requiring both HIC/SSC resistance and uniform through-wall properties. | 475 | 565 | 27 | 188 HB | 9 % IACS |
PSL2, quenched and tempered | Used mainly for heavy-wall seamless pipe, induction bends and fittings where through-thickness strength and toughness must be restored after hot forming. | 480 | 570 | 27 | 185 HB | — |
What is X60MS?
X60MS is X60 in the X60MS grade — specify for wet H₂S (sour) gas/oil lines: very low S, Ca inclusion shape control, HIC/SSC tested, hardness capped for NACE MR0175 compliance. X60MS has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 555 MPa (80.5 ksi) — stronger than 55% of steel grades. Elongation at break is 31% and the elastic modulus is 207 GPa (30 Msi). X60MS has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,490°C (2,714 °F). X60M is the default condition FabDigit quotes; X60MS is available on request or by drawing note.
Advantages
- Tough — resists crack growth — 185 MPa·√m (168.4 ksi·√in), better than 99% of steel grades
- Ductile — tolerates forming and impact — 31%, better than 94% of steel grades
- Forms and bends easily — 76/100, better than 91% of steel grades
- Readily welded — 90/100, better than 90% of steel grades
- Conducts heat well — 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades
Limitations
- Hard to polish — 40/100, worse than 96% of steel grades
X60MS properties
Typical room-temperature values for X60MS; 23 are specific to this condition. Other listed values are X60 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
X60MS has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,490°C (2,714 °F).
Mechanical16
X60MS has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 555 MPa (80.5 ksi) — stronger than 55% of steel grades. Elongation at break is 31% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
X60MS is rated for continuous service to 350°C (662 °F). It conducts heat at 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
X60MS conducts electricity at 9.5 % IACS, better than 75% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (18/100), better than 83% of steel grades.
Sustainability4
Producing a kilogram of X60MS takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability6
X60MS's machinability is good (56/100, better than 71% of steel grades); weldability excellent (90/100); formability very good (76/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with X60MS
Is X60 easy to machine?
Machines like a low-carbon micro-alloyed steel (~55–60 % of AISI 1212); use rigid setups and positive-rake carbide, expect stringy chips due to low sulfur in sour grades.
Can X60 be welded?
Excellent weldability with low CE/Pcm — SAW, GMAW/FCAW and cellulosic SMAW root passes; usually no preheat below ~25 mm wall, keep heat input moderate on TMCP material to avoid HAZ softening.
Can X60 be formed, bent or molded?
Cold formed into pipe by UOE/JCO/spiral and roll-bent readily; allow for springback and Bauschinger yield loss after cold expansion, hot-bent sections should be re-normalized or Q&T.
What surface finishes work on X60?
Bare steel requires protection: shot-blast then FBE/3LPE/3LPP external coating, internal flow coating or liquid epoxy, plus cathodic protection when buried or submerged.
X60 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CPSL2 M/Q grades ≤0.12; PSL1 seamless up to 0.28 | ≤ 0.12 | 0.07 |
| Si | ≤ 0.45 | 0.25 |
| MnPSL1 ≤1.40 | ≤ 1.65 | 1.45 |
| Psour grades ≤0.020 | ≤ 0.03 | 0.01 |
| Ssour (MS/NS/QS) ≤0.003 | ≤ 0.02 | 0 |
| NbNb+V+Ti ≤0.15 total | ≤ 0.05 | 0.04 |
| V | ≤ 0.1 | 0.03 |
| Ti | ≤ 0.04 | 0.02 |
| Cu | ≤ 0.5 | 0.15 |
| Ni | ≤ 0.5 | 0.15 |
| Cr | ≤ 0.5 | 0.1 |
| Mo | ≤ 0.5 | 0.05 |
| BM/Q grades only | ≤ 0 | 3×10⁻⁴ |
| Algrain refining / killed steel | ≤ 0.06 | 0.04 |
| N | ≤ 0.01 | 0.01 |
| Fe | balance | — |
X60MS — frequently asked
What is X60MS used for?
X60MS is typically used for cross-country pipelines, gas transmission and offshore pipe. In short: thinner wall than X52; sour-service variants available; weldable at 465 MPa yield.
What is the yield strength of X60MS?
X60MS has a typical yield strength of 460 MPa (66.7 ksi) and a tensile strength of 555 MPa (80.5 ksi) — stronger than 55% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is X60MS easy to machine?
Reasonably — machinability is rated good (56/100, better than 71% of steel grades). Machines like a low-carbon micro-alloyed steel (~55–60 % of AISI 1212); use rigid setups and positive-rake carbide, expect stringy chips due to low sulfur in sour grades.
Can X60MS be welded?
Yes — weldability is rated excellent (90/100). Excellent weldability with low CE/Pcm — SAW, GMAW/FCAW and cellulosic SMAW root passes; usually no preheat below ~25 mm wall, keep heat input moderate on TMCP material to avoid HAZ softening.
What surface finishes work on X60MS?
Bare steel requires protection: shot-blast then FBE/3LPE/3LPP external coating, internal flow coating or liquid epoxy, plus cathodic protection when buried or submerged.
Can X60MS be formed, bent or molded?
Cold formed into pipe by UOE/JCO/spiral and roll-bent readily; allow for springback and Bauschinger yield loss after cold expansion, hot-bent sections should be re-normalized or Q&T.
What is the maximum service temperature of X60MS?
X60MS is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between X60M and X60Q?
X60M is the default condition — default choice for modern welded (LSAW/HSAW/ERW) transmission pipe: lowest carbon equivalent, best low-temperature toughness and field weldability. X60Q: used mainly for heavy-wall seamless pipe, induction bends and fittings where through-thickness strength and toughness must be restored after hot forming. Yield strength is 465 MPa in X60M versus 480 MPa in X60Q.
Sources
- API Spec 5L, Line Pipe (46th ed.) — American Petroleum Institute (2018)
- ISO 3183 Petroleum and natural gas industries — Steel pipe for pipeline transportation systems — ISO (2019)
- ANSI/NACE MR0175 / ISO 15156 — Materials for use in H2S-containing environments — NACE/ISO (2020)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels and High-Performance Alloys (HSLA steels) — ASM International (1990)
- Line pipe steel plate/coil datasheets (Baosteel, ArcelorMittal, Dillinger) — various mills (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.