Deutsche Version: Formstücke aus 1.4571 (316Ti)
X6CrNiMoTi17-12-2 · Ti-Stabilised 316 · PRE ~24 · AD 2000-Merkblatt W0
Titanium-stabilised 316 stainless steel — the standard 316-family specification for German, Austrian, Italian, and Central European process piping. Same 18% Cr, 10% Ni, 2% Mo chemistry and PRE ~24 as 316L (1.4404), but sensitisation resistance is achieved through titanium stabilisation rather than low carbon. Specify 1.4571 when the project PID or piping class is written to German DIN or Italian UNI conventions.
Both grades achieve the same goal — a 316-family stainless steel that resists sensitisation in the weld heat-affected zone — by different means:
Limit carbon to C ≤ 0.030% — so little carbon is available that chromium carbide cannot form at sensitisation temperatures (450–850°C).
Add titanium (Ti ≥ 5×C, typically 0.40–0.70%) — titanium has stronger affinity for carbon than chromium, so TiC forms preferentially, leaving Cr free in solution.
Corrosion performance in process service: equivalent. Choice is dictated by the engineering company's home-country convention — not by any technical advantage of one approach over the other in normal service.
| System | Designation |
|---|---|
| EN Werkstoffnummer | 1.4571 |
| EN Grade Name | X6CrNiMoTi17-12-2 |
| DIN (old) | X6CrNiMoTi 17 12 2 |
| ASTM — no direct equivalent | Closest: A403 WP316L (different stabilisation method) |
| UK/US equivalent purpose | 1.4404 (316L) — functionally equivalent, different stabilisation |
| PRE | ~24 |
| AWS Filler (GTAW) | ER316L or ER316Ti (match to base metal stabilisation) |
| Element | 1.4571 (316Ti) | 1.4404 (316L) | Note |
|---|---|---|---|
| C | ≤0.080% | ≤0.030% | 316Ti uses higher C — Ti ties it up |
| Ti | 5×C min, ≤0.70% | None | The defining difference — stabiliser |
| Cr | 16.5–18.5% | 16.5–18.5% | Same |
| Ni | 10.5–13.5% | 10.0–13.0% | Essentially same |
| Mo | 2.0–2.5% | 2.0–2.5% | Same |
| PRE | ~24 | ~24 | Identical |
| W.Nr. | Grade | PRE | Key Feature | Market |
|---|---|---|---|---|
| 1.4401 | 316 | ~24 | Standard C (≤0.070%) | Non-welded / dual-cert |
| 1.4404 ★ | 316L | ~24 | Low C (≤0.030%) | UK / NL / Scandinavia / USA |
| 1.4571 ★ | 316Ti | ~24 | Ti-stabilised (≥5×C) | Germany / Austria / Italy / CE Europe |
| 1.4432 | 316L Hi-Mo | ~26 | Mo 2.5–3.0% | Upgraded chloride service |
| 1.4435 | 316L High-Ni | ~26 | Ni 12.5–15%; FN≤1 | Nuclear / Pharma / Fatigue |
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 |
EN 1.4571 (316Ti) and EN 1.4404 (316L) are both 316-family stainless steels with the same Cr, Ni and Mo content — and therefore essentially the same PRE (~24) and corrosion resistance. The difference is how sensitisation is prevented: 1.4404 uses a low carbon limit (C ≤ 0.030%) to prevent chromium carbide formation; 1.4571 uses titanium stabilisation (Ti typically 5×C to 0.70%) to tie up carbon. The choice between them is almost entirely a matter of engineering convention: German, Italian, Austrian, and Central European engineering companies specify 1.4571; UK, Netherlands, Scandinavian, and US companies specify 1.4404 (316L). For a given project, use whichever W.Nr. the customer's specification calls for.
Yes — 1.4571 and 1.4404 are metallurgically compatible. Both are 316-family austenitic stainless steel with equivalent mechanical properties and corrosion resistance. They can be welded together using ER316L filler without additional precautions. However, if the project specification mandates one specific W.Nr., mixing without approval constitutes a deviation — always check the piping class before substituting.
Titanium-stabilised 1.4571 is the established 316-family specification in Germany, Austria, Italy and Central Europe, and is often called up together with AD 2000-Merkblatt W0.
