Steel A182 F11 Cl.1
ASTM A182 F11 Cl.1 · UNS K11597
ASTM A182 F11 Cl.1 is the lower-tensile class of the 1.25Cr-0.5Mo creep-resisting low-alloy forging steel, sharing chemistry with A335 P11 piping (UNS K11597).
Reference datasheet — A182 F11 Cl.1 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the ANN condition
A182 F11 Cl.1 tempers and conditions
A182 F11 Cl.1 is supplied in 4 conditions, soft to hard. ANN is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefault Annealed | Standard supply condition for F11 Cl.1 forgings, flanges and fittings where maximum weldability/softness (≤121 HB) is wanted and only the 415 MPa strength class is required. | 275 | 480 | 30 | 115 HB | — |
A335 P11 pipe | Choose when the same 1.25Cr-0.5Mo chemistry is bought as seamless high-temperature piping rather than forgings. | 290 | 490 | 30 | 145 HB | 7.8 % IACS |
Class 2 | Pick when the piping class calls for the 485 MPa / 275 MPa strength grade of F11 (most common F11 class in refinery valves and fittings). | 380 | 550 | 25 | 170 HB | — |
Class 3 | Used where 515 MPa / 310 MPa minimums are specified for heavy-wall F11 forgings; hardness still capped at 207 HB for wet-H2S service. | 415 | 580 | 24 | 180 HB | — |
What is A182 F11 Cl.1?
ASTM A182 F11 Cl.1 is the lower-tensile class of the 1.25Cr-0.5Mo creep-resisting low-alloy forging steel, sharing chemistry with A335 P11 piping (UNS K11597). It is specified for flanges, valve bodies and fittings in power and refinery piping, typically supplied annealed at 275 MPa yield, 480 MPa tensile, 30 % elongation and about 115 HB, with service to 580 °C. It has no inherent corrosion resistance and requires preheat and PWHT when welded (weldability score 55); machinability is moderate at 58. Where higher strength is needed at the same chemistry, use F11 Cl.2. A182 F11 Cl.1 has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 87% of steel grades. It melts at 1,450°C (2,642 °F). A182 F11 Cl.1 has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 91% of steel grades. Elongation at break is 30% and the elastic modulus is 205 GPa (29.7 Msi).
What is A182 F11 Cl.1 used for?
- High-temperature flanges
- Valve bodies
- Refinery piping fittings
Advantages
- High service temperature — 580°C (1,076 °F), better than 97% of steel grades
- Tough — resists crack growth — 150 MPa·√m (136.5 ksi·√in), better than 96% of steel grades
- Ductile — tolerates forming and impact — 30%, better than 93% of steel grades
Limitations
- Low strength — 275 MPa (39.9 ksi), worse than 91% of steel grades
A182 F11 Cl.1 properties
Typical room-temperature values for A182 F11 Cl.1-ANN; bars are the position among steel grades.
Physical3
A182 F11 Cl.1 has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 87% of steel grades. It melts at 1,450°C (2,642 °F).
Mechanical16
A182 F11 Cl.1 has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 91% of steel grades. Elongation at break is 30% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
A182 F11 Cl.1 is rated for continuous service to 580°C (1,076 °F). It conducts heat at 38 W/m·K (22 BTU/hr·ft·°F), worse than 69% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
A182 F11 Cl.1 conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (20/100), better than 87% of steel grades.
Sustainability4
Producing a kilogram of A182 F11 Cl.1 takes about 31 MJ of energy and emits 2.2 kg of CO₂ — more than 64% of steel grades. Typical recycled content is 30%.
Manufacturability7
A182 F11 Cl.1's machinability is good (58/100, better than 75% of steel grades); weldability good (55/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. A182 F11 Cl.1 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with A182 F11 Cl.1
Is A182 F11 Cl.1 easy to machine?
Annealed Cl.1 machines readily at ~60 % of AISI 1212 with carbide or HSS tooling; low hardness gives gummy chips, so use positive rake, ample coolant and higher feeds.
Can A182 F11 Cl.1 be welded?
P-No.4 material: weld with matching E/ER 80S-B2 (or B2L) consumables, preheat 150–250 °C, interpass ≤315 °C and PWHT 700–760 °C to restore toughness and avoid hard HAZ.
Can A182 F11 Cl.1 be formed, bent or molded?
Hot forge at 1050–1200 °C, finish above 900 °C, then full anneal (~900 °C, furnace cool) for Cl.1; cold bending is possible but limited by 1.25Cr-0.5Mo work hardening.
A182 F11 Cl.1 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 |
|---|---|---|
| C | 0.05 – 0.15 | 0.12 |
| Mn | 0.3 – 0.6 | 0.45 |
| Si | 0.5 – 1 | 0.7 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Cr | 1 – 1.5 | 1.25 |
| Mo | 0.44 – 0.65 | 0.55 |
| Fe | balance | — |
What surface finishes work on A182 F11 Cl.1?
No anodizing; protect with shop primer, phosphating or aluminized/painted systems for atmospheric service, and use high-temperature coatings or insulation under hot piping to limit CUI.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel A182 F11 Cl.1 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- K11597
- ASTM
- A335 P11
How much does A182 F11 Cl.1 cost?
A182 F11 Cl.1 is a standard-cost steel ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
A182 F11 Cl.1 — frequently asked
What is A182 F11 Cl.1 used for?
A182 F11 Cl.1 is typically used for high-temperature flanges, valve bodies and refinery piping fittings. In short: softest 1.25Cr-0.5Mo forging class; creep service to 580 °C; easier machining than Cl.2.
What is the yield strength of A182 F11 Cl.1?
A182 F11 Cl.1 has a typical yield strength of 275 MPa (39.9 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 91% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is A182 F11 Cl.1 easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Annealed Cl.1 machines readily at ~60 % of AISI 1212 with carbide or HSS tooling; low hardness gives gummy chips, so use positive rake, ample coolant and higher feeds.
Can A182 F11 Cl.1 be welded?
Yes — weldability is rated good (55/100). P-No.4 material: weld with matching E/ER 80S-B2 (or B2L) consumables, preheat 150–250 °C, interpass ≤315 °C and PWHT 700–760 °C to restore toughness and avoid hard HAZ.
What surface finishes work on A182 F11 Cl.1?
No anodizing; protect with shop primer, phosphating or aluminized/painted systems for atmospheric service, and use high-temperature coatings or insulation under hot piping to limit CUI.
Can A182 F11 Cl.1 be formed, bent or molded?
Hot forge at 1050–1200 °C, finish above 900 °C, then full anneal (~900 °C, furnace cool) for Cl.1; cold bending is possible but limited by 1.25Cr-0.5Mo work hardening.
What is the maximum service temperature of A182 F11 Cl.1?
A182 F11 Cl.1 is rated for continuous use to about 580°C (1,076 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A182 F11 Cl.1-ANN and A182 F11 Cl.1 NT-CL3?
ANN is the default condition — standard supply condition for F11 Cl.1 forgings, flanges and fittings where maximum weldability/softness (≤121 HB) is wanted and only the 415 MPa strength class is required. NT-CL3: used where 515 MPa / 310 MPa minimums are specified for heavy-wall F11 forgings; hardness still capped at 207 HB for wet-H2S service. Yield strength is 275 MPa in ANN versus 415 MPa in NT-CL3.
How much does A182 F11 Cl.1 cost?
A182 F11 Cl.1 is a standard-cost steel ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A182/A182M — Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Fittings, Valves and Parts for High-Temperature Service — ASTM International (2023)
- ASTM A335/A335M — Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service (P11) — ASTM International (2023)
- ASME BPVC Section II Part D — Materials, Properties (Metric) — ASME (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- API RP 941 — Steels for Hydrogen Service at Elevated Temperatures — API (2016)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.