ASTM A336 F22 Alloy Fittings – Class 1 & Class 3 Supplier
What are ASTM A336 F22 fittings?
They are pipe fittings and pressure parts forged to ASTM A336 / ASME SA336 Grade F22 – a 2¼Cr-1Mo alloy steel (Cr 2.00–2.50%, Mo 0.90–1.10%) made for boilers, pressure vessels and high-temperature service. A336 F22 comes in two strength levels: Class 1 (415–585 MPa tensile) and Class 3 (515–690 MPa tensile).
A336 is a specification for forgings, so A336 F22 fittings are usually heavy-wall or custom forged parts – tees, reducers, nozzles, hubs and large-bore fittings machined from forgings. Standard socket-weld and threaded fittings are normally ordered to ASTM A182 F22, and butt-weld fittings to ASTM A234 WP22.
ASTM A336 F22 – Quick Facts
- Material: 2¼Cr-1Mo alloy steel, ASTM A336 / ASME SA336 Grade F22, Class 1 or Class 3
- Heat treatment: annealed, or normalized and tempered
- Service: steam, hydrogen and high-temperature process lines, commonly up to about 595 °C (1100 °F)
- Product forms: forged tees, crosses, reducers, elbows, nozzles, hubs, rings and discs
- Certificate: EN 10204 3.1; third-party inspection on request
ASC LLP, Mumbai, supplies A336 F22 forged fittings to drawing, along with matching A335 P22 pipes and other alloy steel fittings.
ASTM A336 F22 Chemical Composition
| Element | Composition (wt %) |
| Carbon (C) | 0.05 – 0.15 |
| Manganese (Mn) | 0.30 – 0.60 |
| Phosphorus (P) | 0.025 max |
| Sulphur (S) | 0.025 max |
| Silicon (Si) | 0.50 max |
| Chromium (Cr) | 2.00 – 2.50 |
| Molybdenum (Mo) | 0.90 – 1.10 |
Values are heat analysis and are the same for Class 1 and Class 3. Chromium gives oxidation and hydrogen-attack resistance at temperature; molybdenum gives creep strength.
A336 F22 Class 1 vs Class 3 – Mechanical Properties
| Property | F22 Class 1 | F22 Class 3 |
| Tensile strength | 415 – 585 MPa (60 – 85 ksi) | 515 – 690 MPa (75 – 100 ksi) |
| Yield strength, min | 205 MPa (30 ksi) | 310 MPa (45 ksi) |
| Elongation in 50 mm, min | 20% | 19% |
| Reduction of area, min | 45% | 40% |
| Heat treatment | Annealed, or normalized and tempered (min 675 °C / 1250 °F) | Normalized and tempered |
Which class to choose? Class 1 is the softer, more ductile condition used where design stresses are lower. Class 3 has higher strength and allows thinner walls at the same pressure – check that the design code (ASME Section VIII or B31.3) uses the matching allowable stress.
ASTM A336 F22 vs A182 F22 vs A234 WP22
| Specification | Covers | Typical F22 products |
| ASTM A336 F22 | Alloy steel forgings for boilers, pressure vessels and high-temperature parts | Custom and heavy-wall forged fittings, nozzles, hubs, rings, discs |
| ASTM A182 F22 | Forged piping components – flanges, fittings, valves | Socket-weld and threaded fittings (ASME B16.11), flanges (B16.5) |
| ASTM A234 WP22 | Wrought butt-weld fittings | Elbows, tees, reducers, caps to ASME B16.9 |
| ASTM A335 P22 | Seamless ferritic alloy pipe | Pipe in the same 2¼Cr-1Mo chemistry |
All four share the 2¼Cr-1Mo family chemistry, so they weld together in one P22 piping system. The specification on the order depends on the product form and the project data sheet.
ASTM A336 F22 Fittings Specifications
| Item | Details |
| Product | ASTM A336 F22 alloy steel forged fittings |
| Material standard | ASTM A336 / ASME SA336, Grade F22, Class 1 or Class 3 |
| Dimensional standards | Customer drawing; ASME B16.9 / B16.11 / B16.5 profiles where specified |
| Size range | ½” to large-bore; heavy-wall and non-standard sizes to drawing |
| Wall / schedule | SCH 40, SCH 80, SCH 160, XXS and custom wall to drawing |
| Ends | Butt-weld (bevelled), socket weld, threaded, flanged |
| Testing | Chemical, tensile, hardness, ultrasonic (UT), PMI, dimensional |
| Certificate | EN 10204 3.1; third-party inspection (TPI) on request |
Types of A336 F22 Forged Fittings
| Fitting type | Notes |
| Forged tees & crosses | Equal and reducing; heavy-wall headers |
| Forged reducers | Concentric and eccentric, machined from forgings |
| Forged elbows | 45° and 90°, large-bore and heavy-wall |
| Nozzles & set-on/set-in forgings | For vessels, headers and drums |
| Hubs, blind ends & caps | Machined to drawing |
| Rings, discs & tube sheets | Forged blanks for further machining |
Welding & Equivalent Grades
| Item | Details |
| ASME P-Number | P-No. 5A |
| Typical filler metal | ER90S-B3 (TIG/MIG), E9018-B3 (stick) |
| Preheat | Normally 150 °C (300 °F) minimum per ASME B31.3 |
| Post-weld heat treatment | Typically 705 – 760 °C (1300 – 1400 °F), per the governing code |
| European equivalent | EN 10222-2 11CrMo9-10 (1.7383) |
| Matching grades | A182 F22, A234 WP22, A335 P22, A213 T22 |
Always follow the qualified WPS and the governing code (ASME B31.1, B31.3 or Section VIII) for preheat and PWHT – 2¼Cr-1Mo must not be left in the as-welded condition for pressure service.
Physical Properties of F22 (2¼Cr-1Mo)
| Property | Value (approx.) |
| Density | 7.83 g/cm³ |
| Modulus of elasticity | ≈ 205 GPa at 20 °C |
| Thermal conductivity | ≈ 36 W/m·K at 20 °C |
| Coefficient of thermal expansion | ≈ 12.5 µm/m·°C (20 – 200 °C) |
| Specific heat | ≈ 470 J/kg·K |
Applications of ASTM A336 F22 Fittings
| Industry | Typical uses |
| Power generation | Main steam and hot reheat headers, boiler drum nozzles, superheater fittings |
| Refining | Hydrotreater and hydrocracker piping and reactor nozzles (hydrogen service) |
| Petrochemical | High-temperature process lines, furnace headers, heat-exchanger channels |
| Pressure vessels | Shell and head nozzles, flanged connections, tube sheets |
| Oil & gas processing | High-pressure, high-temperature process piping |
F22 is chosen for heat, pressure and hydrogen – not for wet corrosion. For seawater or acid service a stainless or nickel alloy is the right choice.
ASTM A336 F22 Fittings Supplier & Exporter
ASC LLP supplies A336 F22 Class 1 and Class 3 forged fittings to EPC contractors, boiler makers and refinery projects, with mill test certificates and full heat traceability. We also stock the related grades: A336 F11, A336 F91, A182 F22 flanges and A213 T22 tubes.
Why Buy A336 F22 Fittings from ASC LLP?
- Correct class: Class 1 or Class 3 supplied exactly as ordered, with tensile results on the certificate.
- Testing: chemical, tensile, hardness, UT and PMI; third-party inspection on request.
- Custom forgings: heavy-wall and non-standard fittings machined to your drawing.
- Complete P22 package: pipe, fittings, flanges and tubes in one order.
- Export packing and regular shipments to the Middle East, Europe, USA and Asia.
Send the fitting type, size, wall, class and quantity to sales@amardeepsteel.com or call 022-67439130.
Frequently Asked Questions – ASTM A336 F22 Fittings
What is ASTM A336 F22?
ASTM A336 Grade F22 is a 2¼Cr-1Mo alloy steel forging grade for boilers, pressure vessels and high-temperature parts. It contains 2.00–2.50% chromium and 0.90–1.10% molybdenum and is supplied as Class 1 or Class 3.
What is the difference between A336 F22 Class 1 and Class 3?
Class 1 requires 415–585 MPa tensile and 205 MPa minimum yield. Class 3 is stronger, requiring 515–690 MPa tensile and 310 MPa minimum yield. The chemistry is the same; the difference comes from heat treatment.
What is the difference between ASTM A336 F22 and A182 F22?
Both are forged 2¼Cr-1Mo steel. A182 covers standard forged piping components such as flanges, socket-weld fittings and valves, while A336 covers forgings for boilers, pressure vessels and high-temperature parts – typically larger, heavy-wall or custom forged pieces.
What is the maximum temperature for F22?
2¼Cr-1Mo steel is commonly used up to about 595 °C (1100 °F). The allowable stress at temperature is taken from the governing code, such as ASME B31.1, B31.3 or Section II Part D.
Does A336 F22 need PWHT after welding?
Yes. F22 is ASME P-No. 5A and normally needs preheat (about 150 °C minimum) and post-weld heat treatment, typically 705–760 °C, as required by the governing code and the WPS.
What is the European equivalent of F22?
The nearest European equivalent is EN 10222-2 11CrMo9-10 (material number 1.7383). Check chemistry and mechanical requirements before substituting.
Global Reach
ASC LLP supplies alloy steel pipes, fittings and forgings to power, refinery and petrochemical projects worldwide, with prompt delivery and full documentation. Buyers in the USA, Europe, the Middle East and Asia rely on our ASTM A336 F22 alloy fittings for certified material and traceability.
Countries We Export To
UNITED STATES, EUROPE, UK, UAE, SAUDI ARABIA, OMAN, KUWAIT, JORDAN, QATAR, INDONESIA, MALAYSIA, BRAZIL, SPAIN, ITALY, FRANCE, GERMANY, BAHRAIN, SRI LANKA, AZERBAIJAN, AUSTRALIA, AUSTRIA, PHILIPPINES, TURKEY, RUSSIA, IRAN, IRAQ, CANADA, KOREA, JAPAN, YEMEN, FINLAND, ZIMBABWE, HUNGARY, PORTUGAL, VIETNAM, MOROCCO, THAILAND, SOUTH AFRICA, MEXICO, SINGAPORE, GREECE, KUWAIT, POLAND, NEW ZEALAND, SWEDEN, SWITZERLAND, BELGIUM, BHUTAN, BANGLADESH, TAIWAN, ROMANIA, CAMBODIA, KAZAKHSTAN, AFGHANISTAN.
