SS 317 / 317L Buttweld Fittings are made to ASTM A403 / ASME SA403 WP317, WP317L for acid, pulp and FGD service. Elbows, tees, reducers and caps are dimensioned to ASME B16.9 and bevelled for welding into SS 317 / 317L pipe.
Raaj Fittings manufactures SS 317 / 317L buttweld fittings in-house at our two plants in India, seamless and welded, from ½" upwards, and exports them to EPC contractors, fabricators and stockists across the Middle East, Europe and the Americas, with full traceability and EN 10204 certificates.
| Material specification | ASTM A403 / ASME SA403 WP317, WP317L |
|---|---|
| Construction | Seamless and welded |
| Dimensional standards | ASME B16.9, MSS SP-43; bevelled ends to ASME B16.25 |
| Size range | ½" to 48" NPS; larger sizes to order |
| Wall thickness | SCH 5S, 10S, 40S, 80S and heavier walls to order |
| Certification | EN 10204 3.1 mill test certificate as standard; EN 10204 3.2 on request |
SS 317 and 317L raise the molybdenum of 316 to 3–4% and the chromium and nickel slightly, giving clearly better resistance to pitting and to sulphuric and other reducing acids, while 317L keeps the low carbon needed for welded construction.
| Element, % | 317 | 317L |
|---|---|---|
| Carbon (C) | 0.08 max | 0.030 max |
| Manganese (Mn) | 2.00 max | 2.00 max |
| Phosphorus (P) | 0.045 max | 0.045 max |
| Sulphur (S) | 0.030 max | 0.030 max |
| Silicon (Si) | 1.00 max | 1.00 max |
| Chromium (Cr) | 18.0 – 20.0 | 18.0 – 20.0 |
| Nickel (Ni) | 11.0 – 15.0 | 11.0 – 15.0 |
| Molybdenum (Mo) | 3.0 – 4.0 | 3.0 – 4.0 |
| Property | 317 | 317L |
|---|---|---|
| Tensile strength, min. | 515 MPa (75 ksi) | 485 MPa (70 ksi) |
| Yield strength (0.2%), min. | 205 MPa (30 ksi) | 170 MPa (25 ksi) |
| UNS | Werkstoff Nr. | EN / DIN | Other |
|---|---|---|---|
| S31700 / S31703 | 1.4438 (317L) | X2CrNiMo18-15-4 (317L) | SUS 317 / SUS 317L |
SS 317 / 317L fittings are hot-formed seamless from pipe or made from plate and welded pipe, then solution annealed so that formed and welded areas regain full corrosion resistance. Welded fittings can be ordered with fully radiographed (WX) or ultrasonically tested (WU) seams.
Every heat is PMI-verified and its chemistry and mechanical properties are confirmed against the material specification before the buttweld fittings are released. Each piece is marked with grade, size, rating and heat number for traceability to its EN 10204 3.1 mill test certificate. EN 10204 3.2 certification and inspection by the buyer's nominated third-party agency are available on request, as are PED 2014/68/EU compliance for European projects and IBR certification for Indian boiler applications.
317L has 3–4% molybdenum against 2–3% in 316L, so it resists pitting and acid attack better. It is used where 316L shows corrosion but a nickel alloy would be more than needed.
Yes. Its 0.030% carbon prevents sensitisation, and it is normally welded with a filler of equal or higher molybdenum, such as 317L or a higher-alloyed filler.
Yes. Smaller sizes are normally seamless and larger sizes welded, with weld examination as the specification and your order require. Tell us the size, schedule and any construction requirement.
Every order is supplied with EN 10204 3.1 mill test certificates showing heat chemistry and mechanical properties to ASTM A403 WP317, WP317L. EN 10204 3.2 certification and inspection by your nominated third-party agency are available on request.