Description
Global Standards & Grades
| Region |
Standard |
Grade |
| USA |
ASTM A312/ASME SA-312 |
UNS S30400 |
| Europe |
EN 10216-5 |
1.4301 |
| Japan |
JIS G3459 |
SUS304 TB |
| China |
GB/T 14976 |
06Cr19Ni10 |
Chemical Composition (Weight %)
| Cr |
Ni |
C |
Mn |
Si |
P |
S |
Fe |
| 18–20% |
8–10.5% |
≤0.08% |
≤2.0% |
≤0.75% |
≤0.045% |
≤0.03% |
Balance |
Key Differentiators
Seamless Superiority:
Zero weak points from welding, ensuring 100% NDT (non-destructive testing) compliance per ASTM E213.
Withstands internal pressures up to 35 MPa (Schedule 160 pipes).
Thermal Stability:
Operates continuously at 600°C (1.112°F) with minimal scaling; intermittent use up to 870°C.
Corrosion Resistance:
PREN (Pitting Resistance) of 18–20; handles chlorides ≤100 ppm and sulfuric acid ≤10% concentration.
Surface Quality:
ID/OD finishes: Pickled (Ra ≤3.2 µm), polished (Ra ≤0.8 µm), or sandblasted for enhanced adhesion.
Mechanical Properties
| Condition |
Tensile Strength |
Yield Strength |
Elongation |
Hardness (HRB) |
| Hot-Finished |
515–720 MPa |
205 MPa (min) |
40% (min) |
85–95 |
| Cold-Drawn |
860–1.100 MPa |
550 MPa (min) |
12% (min) |
≤95 |
Industry Applications
Oil & Gas: Subsea umbilicals, hydraulic fracturing manifolds, LNG heat exchangers.
Power Generation: Superheated steam lines, nuclear reactor auxiliary cooling systems.
Chemical Processing: High-pressure acid leaching (HPAL) autoclaves, ammonia synthesis loops.
Aerospace: Hydraulic fluid conduits, fuel injection lines, cryogenic storage.
Pharma: Sterile API transfer lines, clean steam distribution, CIP/SIP-compatible networks.
Fabrication & Testing
Production Methods:
Hot extrusion: For large diameters (OD 100–600 mm).
Cold drawing: Precision sizing for OD 6–120 mm with ±0.1 mm tolerance.
Quality Assurance:
100% ultrasonic testing (UT) for wall integrity.
Hydrostatic testing at 1.5x design pressure (ASME B31.3 compliant).
Frequently Asked Questions
Q1: Why choose seamless over welded 304 pipes?
A1: Seamless pipes eliminate weld defects, offering superior fatigue resistance for cyclic pressure/vibration environments (e.g., ASME B31.1 Power Piping).
Q2: Can seamless 304 pipes handle sour service (H₂S environments)?
A2: Limited to mild sour conditions (NACE MR0175 Group I). For severe H₂S, specify 316L or duplex 2205.
Q3: What end finishes are available?
A3: Options include plain, beveled (ASME B16.25), threaded (NPT, BSP), or grooved (Victaulic-style).
Q4: How to prevent intergranular corrosion in sensitized zones?
A4: Post-fabrication solution annealing at 1.040–1.120°C followed by rapid quenching.
