Description
Global Standards & Grades
| Region |
Standard |
Grade |
| USA |
ASTM A312/A358 |
UNS S30403 |
| Europe |
EN 1.4306 |
X2CrNi18-10 |
| Japan |
JIS SUS304L |
- |
| China |
GB 022Cr19Ni10 |
- |
Chemical Composition (Weight %)
| Element |
Cr |
Ni |
C |
Mn |
Si |
P |
S |
Fe |
| Content |
18–20% |
8–12% |
≤0.03% |
≤2.0% |
≤0.75% |
≤0.045% |
≤0.03% |
Balance |
Core Advantages
Weldability Excellence:
No post-weld heat treatment required, minimizing downtime in fabrication.
Resists intergranular corrosion in welded joints (ASTM A262 Practice E compliant).
Corrosion Resistance:
Handles oxidizing acids (e.g., nitric acid ≤65%), freshwater, and sterilizing agents.
PREN (Pitting Resistance): 18–20—suitable for urban/industrial atmospheres.
Hygienic Compliance:
Electropolished (Ra ≤0.25 µm) or pickled finishes meet FDA 21 CFR 177.2600 and 3-A Sanitary Standards.
Sustainability:
75% recycled content, certified by ISO 14021 for eco-conscious projects.
Mechanical Properties
| Condition |
Tensile Strength |
Yield Strength |
Elongation |
Hardness (HB) |
| Annealed |
485–620 MPa |
170 MPa (min) |
40% (min) |
201 |
| Cold-Worked |
860–1.100 MPa |
690 MPa (min) |
15% (min) |
310 |
Industry Applications
Food & Beverage: Brewery fermentation tanks, dairy CIP systems, sauce transfer pipelines.
Pharmaceutical: API reactor tubing, purified water distribution loops, autoclave vents.
Chemical: Acetic acid storage, fertilizer production manifolds, solvent recovery systems.
Architecture: Handrails, curtain wall supports, art installations in indoor/low-salinity zones.
Energy: Hydronic heating circuits, geothermal preheat exchangers, biodiesel transfer lines.
Fabrication Tips
Welding: Use ER308L/ER309L filler wire with argon backing gas for root protection.
Bending: Minimum bend radius = 2x pipe OD (annealed) or 4x OD (cold-worked).
Cleaning: Avoid chloride-containing cleaners; opt for alkaline detergents (pH 7–11).
Frequently Asked Questions
Q1: Why choose 304L over standard 304 pipes?
A1: 304L’s ultra-low carbon prevents sensitization in welded zones, critical for ASME B31.3 process piping.
Q2: Can 304L withstand marine environments?
A2: Limited to short-term exposure. For coastal use, upgrade to 316L with 2–3% molybdenum.
Q3: What surface finishes are available?
A3: Options include pickled (mill finish), electropolished, brushed (No. 4), or PVD-coated for aesthetics.
Q4: Is 304L suitable for high-pressure steam lines?
A4: Yes, up to 425°C (ASME B31.1 Power Piping). For >500°C, consider stabilized grades like 321H.
Q5: How to maintain 304L pipes in acidic service?
A5: Schedule annual passivation with 20% nitric acid and inspect for pitting with PT/MT testing.
