ASTM A182 F317L Forgings, UNS S31703 / EN 1.4438
Forged rings, seamless rolled rings, flanges, round bars, shafts, discs, sleeves, bushings, tube sheets and valve bodies
Technical data maintained by Jiangyin Jiangnan Metal Co., Ltd., reviewed 29 September 2026
ASTM A182 Grade F317L is the forging grade of 317L molybdenum-bearing austenitic stainless steel, UNS S31703, nominally 19 % Cr, 13 % Ni and 3.5 % Mo, with carbon held to 0.030 % max. The 3 to 4 % molybdenum improves resistance to general corrosion and to pitting and crevice attack compared with Type 304, while the low carbon limits sensitisation in the weld heat-affected zone.
ASTM A182/A182M requires F317L to be solution treated and quenched from 1900 °F [1040 °C] minimum in a liquid medium, cooled below 500 °F [260 °C], and to meet 485 MPa tensile, 170 MPa yield, 30 % elongation and 50 % reduction of area as minimums. Jiangyin Jiangnan Metal Co., Ltd., an open-die forging factory in Jiangyin, Jiangsu, China, supplies F317L forgings to drawing with EN 10204 3.1 or 3.2 certification and EN 10228-4 ultrasonic examination.
- Grade symbol
- ASTM A182 F317L
- UNS
- S31703
- EN number
- 1.4438 (X2CrNiMo18-15-4)
- Structure
- Austenitic, non-hardenable
- Nominal alloy
- 19 Cr, 13 Ni, 3.5 Mo
- Density
- 8.0 g/cm³
- A182 weight limit
- 10 000 lb [4540 kg]
- Above that limit
- ASTM A965/A965M
Chemical composition of A182 F317L
The table reproduces the chemical requirements of ASTM A182/A182M for Grade F317L. A chemical heat analysis is made for every heat and must conform to the specification table. The purchaser may additionally call for a product analysis.
| Grade | C | Mn | P | S | Si | Ni | Cr | Mo | Fe |
|---|---|---|---|---|---|---|---|---|---|
| F317L | 0.030 max | 2.00 max | 0.045 max | 0.030 max | 1.00 max | 11.0-15.0 | 18.0-20.0 | 3.0-4.0 | Balance |
Nitrogen is not a specified element for F317L in the A182 chemical table. Mill datasheets for 317L plate and bar often quote N 0.10 % max and Si 0.75 % max, which are product-form values rather than A182 forging limits. A182 also prohibits free-machining additions such as lead or selenium.
Mechanical properties
These are the values a purchaser can enforce on an A182 F317L forging. One tension test is made for each heat of austenitic material, and the test blank is heat treated together with the finished forging.
| Property | Requirement |
|---|---|
| Tensile strength, min | 70 ksi [485 MPa] |
| Yield strength, 0.2 % offset, min | 25 ksi [170 MPa] |
| Elongation in 2 in. [50 mm] or 4D, min | 30 % |
| Reduction of area, min | 50 % |
Typical published values for annealed 317L, indicative rather than specified, give roughly 595 MPa tensile, 260 MPa yield, about 55 % elongation, 85 HRB hardness, modulus of elasticity near 200 GPa and Poisson's ratio of 0.27 to 0.30. Datasheets written against ASTM A240 or ASME SA-240 plate quote minimums of 515 MPa tensile, 205 MPa yield and 40 % elongation with a 95 HRB hardness limit. Those are useful for comparison but are not the acceptance criteria for a forging ordered to A182.
Heat treatment and hot working
After hot working, A182 forgings are cooled below 1000 °F [538 °C] before heat treatment begins. Grade F317L is then solution treated and quenched, with a solutioning temperature of 1900 °F [1040 °C] minimum, a liquid cooling medium, and quenching to below 500 °F [260 °C]. Tempering is not applicable to this grade. A182 also permits an alternative route for austenitic grades, namely individual rapid quenching straight from the forging operation, provided the forging temperature has not dropped below the specified minimum solution annealing temperature. Where that route is used, the test blank is forged and quenched under the same conditions as the parts it represents.
For hot working, 317L is heated to roughly 1149 to 1260 °C (2100 to 2300 °F) and should not be worked below about 927 °C (1700 °F), with a post-work anneal to restore corrosion resistance. The grade is fully austenitic and does not respond to hardening heat treatment. Strength can only be raised by cold work, which is generally avoided in pressure-part forgings.
Melting practice
ASTM A182 requires stainless steels to be melted by electric furnace, optionally with separate degassing and refining, by vacuum furnace, or by either followed by vacuum or electroslag consumable remelting. Sufficient discard is taken to ensure freedom from injurious piping and undue segregation. Our F317L is produced from EAF plus VOD refined heats, with ESR available where the application or the customer specification calls for remelted material.
Equivalent designations
| System | Designation |
|---|---|
| ASTM / ASME forging | A182 F317L, SA-182 F317L |
| UNS | S31703 |
| AISI / SAE | 317L, 30317L |
| EN (Germany) | 1.4438, X2CrNiMo18-15-4 |
| Sweden | SS 2367 |
| AFNOR (France) | Z3 CND 19.15 |
| Other product forms | ASTM A240 plate, A312 pipe, A213 and A249 tube, A276 and A479 bar, A403 fittings |
F317L forged product forms
Jiangyin Jiangnan Metal Co., Ltd. produces F317L by open-die forging, upsetting and ring rolling, finished to drawing or to dimensional standards such as ASME B16.5 and B16.47 for flanges. Regular F317L items include forged and seamless rolled rings, weld-neck, slip-on and blind flanges, round bars and stepped shafts, discs and blanks, sleeves, bushings, hollow forged tubes, tube sheets, nozzles, spindles, gear blanks, crankshafts, rolls, manifolds, and valve components such as bodies, bonnets, stems, seat rings and valve blocks for ball, gate, globe, check and plug valves.
Two rules in A182 govern what may legitimately be supplied. Flanges of any type, elbows, return bends, tees and header tees shall not be machined directly from bar stock. Cylindrically shaped austenitic stainless parts may be machined from forged or rolled solution-annealed bar without additional hot working. We quote accordingly and state the manufacturing route on the certificate.
Because A182 caps product weight at 10 000 lb [4540 kg], heavier single-piece F317L forgings are offered under ASTM A965/A965M, the austenitic forging specification for pressure and high-temperature parts.
Testing, examination and certification
Every F317L order is supplied with a mill certificate to EN 10204 type 3.1, issued by our own authorised inspection representative, or to type 3.2, which adds countersignature and verification by an independent third party such as SGS, BV, TUV or Lloyd's. Ultrasonic examination of austenitic F317L is carried out to EN 10228-4, the part of that series written for austenitic and austenitic-ferritic stainless steel forgings, or to ASTM A388/A388M where an American practice is specified. EN 10228-3 and SEP 1921, which suppliers frequently quote for stainless, are written for ferritic and martensitic forgings and are not appropriate acceptance standards for this grade.
Further examination is available on request: liquid penetrant to ASTM E165, macroetch to ASTM E340, grain size to ASTM E112, and intergranular corrosion testing to ASTM A262. The A182 supplementary requirements call for austenitic stainless steels to pass intergranular corrosion testing in accordance with Practice E of A262, and Practice B or ASTM G28 A can be added for severe service. Positive material identification, impact testing and hardness surveys are quoted as options.
Machining and welding
317L work-hardens readily, so machining calls for low speeds with constant, uninterrupted feeds, rigid setups and sharp tooling. The grade is tougher than Type 304 and produces a long stringy chip, so chip breakers are recommended. Welding can be done by most conventional fusion and resistance processes using AWS E317L or ER317L filler. Oxyacetylene welding should be avoided. Annealing after fabrication is recommended following shearing, stamping, heading or drawing, to relieve internal stresses and restore corrosion resistance.
Where F317L forgings are used
The molybdenum content puts F317L into service wherever 316L is marginal. Typical applications include pulp and paper digesters, bleach plants and paper mill equipment, flue-gas desulphurisation stack liners and scrubbers, condensers in fossil-fuelled and nuclear power stations, petroleum refining and catalytic recovery systems, recuperators and thermal oxidisers in waste treatment, chemical, petrochemical and pharmaceutical process equipment, slurry tanks, storage tanks and valves, and offshore and onshore oil and gas hardware including subsea and deepwater production components, air compressors, power generators and nitrogen generators. Food, marine and architectural work draws on the same grade.
Frequently asked questions
Is F317L the same as 317L plate?
Chemically they are the same alloy, UNS S31703, but the acceptance requirements differ. F317L is the ASTM A182 forging grade for pressure parts, while 317L plate is ordered to ASTM A240 with different minimum mechanical properties. Quoting A240 values on a forging order is a common documentation error.
How does F317L compare with F316L?
Both are low-carbon molybdenum-bearing austenitic grades, but F317L carries 3.0 to 4.0 % Mo against roughly 2 to 3 % for 316L, with higher nickel at 11.0 to 15.0 %. That raises resistance to pitting and crevice corrosion in chloride and sulphur-bearing media, which is why it is chosen for bleach plants and FGD service.
What is the minimum order quantity?
We forge to order from single prototype pieces upward, since open-die forging does not require dies. Send a drawing or the rough dimensions, the standard to be met and the certification type needed, and we will quote weight, lead time and price.
Do you supply other 317 variants?
Yes. Alongside F317L we forge F317, F317LN, F316L, F321, F347, the duplex grades F51, F53, F55, F60 and F61, the super austenitic grades F44 and 904L, and nickel alloys such as Inconel 625 and 718 and Hastelloy C-276.
Request an A182 F317L quotation
Send the drawing, dimensions or finished weight, the applicable standard, and your NDT and certification requirements. Price depends on grade, finished weight and the certification called for, so every enquiry is quoted individually. Quotations are normally returned within one working day.
Company Jiangyin Jiangnan Metal Co., Ltd., Open-Die Forging Factory
Address No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
Phone +86-189-2135-9659
E-mail sales@steelforgepieces.com
How to cite this page: "ASTM A182 F317L Forgings, UNS S31703 / EN 1.4438", technical datasheet, Jiangyin Jiangnan Metal Co., Ltd., Jiangyin, Jiangsu, China, reviewed 29 September 2026. Requirements quoted from ASTM A182/A182M, equivalents from EN 10088, examination per EN 10228-4 and ASTM A388/A388M, certification per EN 10204.