Stainless Steel 317L Pipe & Tube Supplier – ASTM A312 TP317L
ASC LLP supplies 317L stainless steel pipe and tube – seamless, welded and ERW – to ASTM A312 / ASME SA312 TP317L (UNS S31703, EN 1.4438). Our SS 317L pipes and tubes are used in chemical processing, pulp and paper, flue-gas desulphurisation and other corrosive service where 316L is not enough, and are supplied with mill test certificates and export packing.
What is 317L Stainless Steel?
317L is a low-carbon, molybdenum-bearing austenitic stainless steel. Compared with 316L it contains more chromium (18–20%), nickel (11–15%) and especially molybdenum (3–4% against 2–3%), which gives clearly better resistance to pitting, crevice corrosion and attack by sulphuric, acetic and other process acids. Its pitting resistance equivalent number (PREN) is roughly 30–34, against about 24 for 316L.
The “L” means low carbon (0.035% max in pipe). This prevents chromium-carbide precipitation during welding, so 317L stainless steel pipe keeps its intergranular corrosion resistance in the as-welded condition without post-weld heat treatment. Its standard-carbon sister grade is 317 stainless steel pipe (UNS S31700).
Key Properties of 317L Stainless Steel Pipe
- Better pitting and crevice resistance than 316L: higher molybdenum (3–4%) raises PREN to about 30–34.
- Acid resistance: good in sulphuric, acetic, formic and phosphoric acid media and in sulphur-bearing process streams.
- Weldability: low carbon prevents sensitisation, so welded joints resist intergranular corrosion.
- Strength: 515 MPa tensile and 205 MPa yield minimum, the same as 316L.
- Formability: fully austenitic and non-magnetic in the annealed condition; easy to bend and fabricate.
317 vs 317L vs 316L Stainless Steel
| Property | 316L (S31603) | 317 (S31700) | 317L (S31703) |
| Carbon, max | 0.035% | 0.08% | 0.035% |
| Chromium | 16 – 18% | 18 – 20% | 18 – 20% |
| Nickel | 10 – 14% | 11 – 15% | 11 – 15% |
| Molybdenum | 2 – 3% | 3 – 4% | 3 – 4% |
| PREN (approx.) | 24 | 30 – 34 | 30 – 34 |
| Weld sensitisation | Resistant | Can sensitise | Resistant |
| Best for | General corrosive service | Higher-temperature strength | Welded systems in aggressive media |
Summary: choose 317L over 316L pipe when chlorides, acids or sulphur compounds cause pitting in 316L. Choose 317L rather than 317 for welded piping.
317L Stainless Steel Pipe Size & Schedule Chart
| NPS | OD (in) | Sch 10S WT (in) | Sch 40S WT (in) | Sch 80S WT (in) |
| 1/8″ | 0.405 | 0.049 | 0.068 | 0.095 |
| 1/4″ | 0.540 | 0.065 | 0.088 | 0.119 |
| 1/2″ | 0.840 | 0.083 | 0.109 | 0.147 |
| 1″ | 1.315 | 0.109 | 0.133 | 0.179 |
| 2″ | 2.375 | 0.109 | 0.154 | 0.218 |
| 4″ | 4.500 | 0.120 | 0.237 | 0.337 |
| 6″ | 6.625 | 0.134 | 0.280 | 0.432 |
| 8″ | 8.625 | 0.148 | 0.322 | 0.500 |
Wall thicknesses per ASME B36.19M. Other sizes from 1/8″ to 24″ NB, schedules 5S to XXS, and tubes from 6 mm OD are available on request.
Mechanical Properties of 317L Stainless Steel Pipe
| Property | ASTM A312 TP317L |
| Tensile strength, min | 515 MPa (75 ksi) |
| Yield strength (0.2%), min | 205 MPa (30 ksi) |
| Elongation in 50 mm, min | 35% |
| Hardness (typical) | ≤ 217 HB / ≤ 95 HRB |
Specifications & Equivalent Grades of 317L Pipe
| Item | Details |
| Pipe standards | ASTM A312 / ASME SA312 (seamless & welded), ASTM A358 (EFW), ASTM A778 (unannealed welded) |
| Tube standards | ASTM A213, A269, A249 (seamless and welded tubes) |
| Grade | TP317L |
| UNS | S31703 |
| EN / Werkstoff Nr. | 1.4438 (X2CrNiMo18-15-4) |
| JIS | SUS317L (JIS G3459 pipe) |
| Types | Seamless, welded, ERW, EFW, U-tubes |
| Size range | 1/8″ – 24″ NB; tubes from 6 mm OD |
| Schedules | 5S, 10S, 40S, 80S, 160, XXS |
| Ends | Plain, bevelled, threaded |
| Test certificate | EN 10204 3.1; third-party inspection on request |
Physical Properties of 317L Stainless Steel
| Property | Value (approx.) |
| Density | 8.0 g/cm³ |
| Melting range | 1370 – 1400 °C |
| Modulus of elasticity | 193 – 200 GPa |
| Thermal conductivity (100 °C) | 16.3 W/m·K |
| Specific heat (0–100 °C) | 500 J/kg·K |
| Electrical resistivity | 0.79 µΩ·m |
| Magnetic | Non-magnetic (annealed) |
Chemical Composition of 317L Stainless Steel Pipe (ASTM A312, UNS S31703)
| Element | Composition (%) |
| Carbon (C) | 0.035 max |
| Manganese (Mn) | 2.00 max |
| Silicon (Si) | 1.00 max |
| Phosphorus (P) | 0.045 max |
| Sulphur (S) | 0.030 max |
| Chromium (Cr) | 18.0 – 20.0 |
| Nickel (Ni) | 11.0 – 15.0 |
| Molybdenum (Mo) | 3.0 – 4.0 |
| Iron (Fe) | Balance |
Limits for pipe per ASTM A312. Plate and sheet to ASTM A240 have slightly tighter carbon (0.030 max) and silicon (0.75 max) limits.
Applications of 317L Stainless Steel Pipes
| Industry | Applications |
| Chemical processing | Piping and heat exchangers handling acids and chloride-bearing process streams |
| Pulp & paper | Bleach plant piping and digester equipment |
| Power / FGD | Flue-gas desulphurisation scrubber and absorber piping |
| Petrochemical & refining | Condensers, sour-water and process piping |
| Pharmaceutical | Process piping requiring high corrosion resistance |
| Food & dyeing | Equipment handling brines, vinegar and dye liquors |
| Marine & desalination | Seawater-exposed piping (moderate chloride service) |
Why Buy 317L Stainless Steel Pipe from ASC LLP?
- Certified material: ASTM A312 / ASME SA312 TP317L with EN 10204 3.1 mill test certificates.
- Testing: hydrostatic or eddy-current testing, PMI and IGC (ASTM A262) on request; third-party inspection available.
- Full range: seamless, welded and ERW pipes, tubes, and matching 317L flanges, fittings and fasteners.
- Cut-to-length and export-ready: cut pieces and seaworthy packing for delivery worldwide.
RelatedProducts
Frequently Asked Questions – 317L Stainless Steel Pipe
What is 317L stainless steel pipe used for?
317L pipe is used in chemical processing, pulp and paper bleach plants, flue-gas desulphurisation, refinery and pharmaceutical piping – anywhere acids, chlorides or sulphur compounds would pit 316L.
What is the difference between 316L and 317L?
317L has more chromium, nickel and molybdenum than 316L (3–4% Mo against 2–3%), giving a higher PREN of about 30–34 against 24 and better resistance to pitting and acids. Both have the same minimum strength.
What is the difference between 317 and 317L?
317L has a maximum carbon content of 0.035% against 0.08% for 317. The lower carbon prevents sensitisation during welding, so 317L is preferred for welded pipe systems.
What is the equivalent of 317L stainless steel?
317L is equivalent to UNS S31703, EN 1.4438 (X2CrNiMo18-15-4) and JIS SUS317L. Pipe is covered by ASTM A312 / ASME SA312 grade TP317L.
Is 317L stainless steel magnetic?
No. 317L is austenitic and non-magnetic in the annealed condition, although cold working can make it slightly magnetic.
What is the PREN of 317L?
The pitting resistance equivalent number (PREN = %Cr + 3.3 × %Mo + 16 × %N) of 317L is typically about 30–34.
Global Reach
ASC LLP has a robust global presence, committed to delivering unparalleled service and quality to clients around the world. Our dedication to prompt delivery and exceptional customer care sets us apart in the industry. Major corporations across the USA, Europe, Asia, and other regions place their trust in our high-quality 317L stainless steel pipes and tubes. This widespread trust underscores our reputation for reliability and excellence. By consistently meeting and exceeding the expectations of our international clientele, we continue to solidify our position as a leader in the global steel market.
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.
