Description
Global Standards & Grades
| Region |
Standard |
Grade |
| USA |
ASTM A312/ASME SA-312 |
UNS S31600 |
| Europe |
EN 1.4401 |
X5CrNiMo17-12-2 |
| Japan |
JIS G3459 |
SUS316 TB |
| China |
GB/T 14976 |
06Cr17Ni12Mo2 |
Chemical Composition (Weight %)
| Cr |
Ni |
Mo |
C |
Mn |
Si |
P |
S |
| 16–18% |
10–14% |
2–3% |
≤0.08% |
≤2.0% |
≤0.75% |
≤0.045% |
≤0.03% |
Key Differentiators
Chloride Domination:
Resists pitting/crevice corrosion in seawater (Cl⁻ ≤20.000 ppm) and brine solutions up to 60°C.
Passivates rapidly after mechanical damage, unlike conventional alloys.
Bio-Industry Edge:
Electropolished (Ra ≤0.2 µm) variants meet FDA 21 CFR 177.1520 for pharmaceutical/biotech fluid transfer.
Cryogenic Toughness:
Maintains impact strength down to -196°C (-320°F), ideal for LNG terminal piping.
Stress Corrosion Immunity:
Withstands SCC in chloride-rich, high-tensile stress environments (NACE TM0177 Method A compliant).
Mechanical Properties
| Condition |
Tensile Strength |
Yield Strength |
Elongation |
Hardness (HRB) |
| Hot-Finished |
515–690 MPa |
205 MPa (min) |
40% (min) |
85–95 |
| Cold-Worked |
760–1.030 MPa |
550 MPa (min) |
15% (min) |
≤95 |
Critical Applications
Marine: Subsea risers, ballast water systems, offshore rig cooling loops.
Chemical: Sulfuric acid (≤20%) distribution, chlorine dioxide reactor coils.
Medical: Sterile CIP/SIP piping, vaccine production bioreactor liners.
Energy: Geothermal brine extraction, flue gas desulfurization (FGD) scrubbers.
Food: Ultra-clean dairy processing, high-pressure homogenizer lines.
Quality Assurance Protocols
Material Verification:
PMI (Positive Material Identification) via XRF to confirm Mo content ≥2.05%.
Surface Integrity:
Ferroxyl testing per ASTM A967 to validate passivation quality.
Performance Testing:
Huey test (ASTM A262 Practice C) for intergranular corrosion resistance.
Frequently Asked Questions
Q1: Why choose 316 over 316L for welded systems?
A1: 316L (≤0.03% C) prevents carbide precipitation in weld zones. Use 316 only for thin-walled, non-welded high-strength applications.
Q2: Is it suitable for urea production environments?
A2: No—upgrade to 316L mod (UNS S31603) with low carbon and nitrogen for urea-grade compliance.
Q3: What’s the maximum continuous service temperature?
A3: 870°C (1.598°F) in oxidizing atmospheres; limit to 540°C (1.004°F) in sulfidic conditions.
Q4: How to prevent galvanic corrosion when paired with carbon steel?
A4: Insulate joints with dielectric unions and apply zinc-rich primers on carbon steel surfaces.
Q5: Acceptable cleaning methods for biofouling prevention?
A5: CIP cycles with 1–2% nitric acid or enzymatic cleaners (pH 2–3) at 60–80°C.
