EN 10253-4 Type B buttweld pipe fittings in 1.4307 — the European designation for 304L stainless steel (X2CrNi18-9, S30403). General-purpose austenitic stainless steel without molybdenum. The standard cryogenic-service stainless steel — maintains full ductility at −196°C due to its FCC crystal structure.
| Element | Min | Max | Function |
|---|---|---|---|
| C (Carbon) | — | 0.030% | Low C prevents sensitisation in welded service |
| Cr (Chromium) | 17.5% | 19.5% | Passive oxide film — primary corrosion protection |
| Ni (Nickel) | 8.0% | 10.5% | Austenite stabiliser; SCC resistance |
| Mo (Molybdenum) | — | — | None — 304L has no Mo (vs 316L) |
| N (Nitrogen) | — | 0.11% | Mild PRE enhancement |
| Mn | — | 2.0% | — |
| Si | — | 1.0% | — |
| Property | 1.4307 (304L) | 1.4404 (316L) |
|---|---|---|
| Mo content | None | 2.0–2.5% |
| PRE | ~18 | ~24 |
| Cryogenic suitability | Excellent (−196°C) | Excellent (−196°C) |
| Chloride resistance | Low — not for seawater | Moderate — mild chloride |
| Cost | Lower (no Mo) | Higher |
| Use for LNG piping | Yes — preferred | Yes — if chloride present |
| Use for food/pharma utility | Yes | Yes (higher cost for same result) |
LNG transfer piping, liquid nitrogen, liquid argon, LOX service. Impact-tested at −196°C. FCC austenitic structure — no ductile-to-brittle transition.
Brewing, dairy, beverage processing, water treatment. No Mo — cost-optimal where chloride resistance is not required.
Plant utility water, non-chloride process, instrument air, nitrogen purge lines, clean condensate. Standard choice for non-aggressive service.
Non-product-contact cooling water, secondary utility. Use 1.4435 (≤1 FN) for WFI contact — 1.4307 for utility loops only.
| W.Nr. | 1.4307 |
| EN Name | X2CrNi18-9 |
| ASTM UNS | S30403 |
| ASTM Grade | A403 WP304L |
| Common Name | 304L |
Filler: ER308L (AWS A5.9). Low-carbon filler matches base metal carbon control — no PWHT required for austenitic stainless. Solution anneal if sensitisation risk in heat-affected zone for critical service.
90° Elbows (LR/SR) · 45° Elbows · Equal Tees · Reducing Tees · Concentric Reducers · Eccentric Reducers · Pipe Caps · Stub Ends per EN 10253-4 Type B
DN15–DN600 and larger. Outside diameters follow the EN 10220 / EN ISO 1127 pipe series; wall thickness is matched to your connecting pipe.
| Size | OD (mm) |
|---|---|
| DN 15 | 21.3 |
| DN 20 | 26.9 |
| DN 25 | 33.7 |
| DN 32 | 42.4 |
| DN 40 | 48.3 |
| DN 50 | 60.3 |
| DN 65 | 76.1 |
| DN 80 | 88.9 |
| DN 100 | 114.3 |
| DN 125 | 139.7 |
| DN 150 | 168.3 |
| DN 200 | 219.1 |
| DN 250 | 273.0 |
| DN 300 | 323.9 |
| DN 350 | 355.6 |
| DN 400 | 406.4 |
| DN 450 | 457.0 |
| DN 500 | 508.0 |
| DN 600 | 610.0 |
Both 1.4307 and 1.4306 are low-carbon 304L grades. 1.4307 (X2CrNi18-9) is the current designation per EN 10088-4 and the preferred grade for fittings — C ≤0.030%, N ≤0.11%, Cr 17.5–19.5%, Ni 8.0–10.5%. 1.4306 (X2CrNi19-11) has slightly higher Ni (10.0–12.0%) and Cr (18.0–20.0%) but similar corrosion resistance. For EN 10253-4 fittings, 1.4307 is the standard 304L designation.
Yes — 1.4307 (304L) is the standard material for LNG piping. Its FCC (face-centred cubic) austenitic crystal structure maintains full ductility at cryogenic temperatures. Charpy V-notch impact energy at −196°C typically exceeds 100J for solution-annealed 304L. The grade is routinely impact-tested at −196°C per EN 10253-4 requirements for cryogenic service. No special cryogenic grade is needed — standard 1.4307 with impact test documentation is correct.
X2CrNi18-9 (UNS S30403), the European designation for 304L.
Supplying an Indian boiler or ASME B16.9 project? The equivalent grade is listed on our group site ibrfittings.com: ASTM A403 WP304L fittings.
