1. Product Overview
TP304LN stainless steel seamless pipe is a low-carbon (≤0.03%)
variant of the classic TP304L alloy, with the addition of nitrogen
to enhance mechanical strength and corrosion resistance. This
seamless pipe eliminates welded joints, ensuring uniform structure,
high pressure resistance, and reliability—making it ideal for
demanding industrial and commercial applications. All pipes listed
here feature a fixed length of 6m, with nominal diameters (DN) of
DN80, DN100, DN150, and DN200, meeting global standards for
dimensional accuracy and performance.
2. Key Specifications
The following table details the critical dimensional and material
specifications of the TP304LN seamless pipes:
| Parameter | Specification (DN80) | Specification (DN100) | Specification (DN150) | Specification (DN200) |
|---|
| Nominal Diameter (DN) | DN80 | DN100 | DN150 | DN200 |
| Outside Diameter (OD) | 88.9 mm | 114.3 mm | 168.3 mm | 219.1 mm |
| Standard Wall Thickness | 4.05 mm (Sch 40) / 6.35 mm (Sch 80) | 4.57 mm (Sch 40) / 7.11 mm (Sch 80) | 5.59 mm (Sch 40) / 8.74 mm (Sch 80) | 6.35 mm (Sch 40) / 10.31 mm (Sch 80) |
| Length | 6m (fixed, ±5mm tolerance) | 6m (fixed, ±5mm tolerance) | 6m (fixed, ±5mm tolerance) | 6m (fixed, ±5mm tolerance) |
| Material Grade | TP304LN (AISI 304LN / UNS S30453) | TP304LN (AISI 304LN / UNS S30453) | TP304LN (AISI 304LN / UNS S30453) | TP304LN (AISI 304LN / UNS S30453) |
| Surface Finish | Annealed & Pickled (AP) / Bright Annealed (BA) | Annealed & Pickled (AP) / Bright Annealed (BA) | Annealed & Pickled (AP) / Bright Annealed (BA) | Annealed & Pickled (AP) / Bright Annealed (BA) |
3. Chemical Composition (ASTM A312/A312M Standard)
TP304LN’s corrosion resistance and mechanical properties are
determined by its strict chemical composition, as follows (all
values are in weight percentage, wt%):
| Element | Minimum Content | Maximum Content | Role |
|---|
| Chromium (Cr) | 18.00% | 20.00% | Enhances oxidation and general corrosion resistance |
| Nickel (Ni) | 8.00% | 12.00% | Improves ductility and resistance to chloride-induced stress
corrosion |
| Carbon (C) | — | 0.03% | Low carbon content prevents carbide precipitation (critical for
weldability) |
| Nitrogen (N) | 0.10% | 0.16% | Boosts tensile strength and hardness without sacrificing ductility |
| Manganese (Mn) | — | 2.00% | Aids in steel melting and improves workability |
| Silicon (Si) | — | 1.00% | Enhances high-temperature oxidation resistance |
| Phosphorus (P) | — | 0.045% | Controlled to avoid brittleness |
| Sulfur (S) | — | 0.030% | Minimized to prevent corrosion and brittleness |
4. Mechanical Properties
TP304LN seamless pipes exhibit excellent strength, ductility, and
toughness, compliant with ASTM A312/A312M and ASME B36.19
standards:
| Property | Test Standard | Minimum Value |
|---|
| Tensile Strength (UTS) | ASTM A370 | 515 MPa (75 ksi) |
| Yield Strength (0.2% offset) | ASTM A370 | 205 MPa (30 ksi) |
| Elongation (in 50mm) | ASTM A370 | 35% |
| Hardness (Brinell) | ASTM E10 | ≤217 HB |
| Impact Toughness (Charpy V-notch) | ASTM A370 | ≥27 J at -196°C (-321°F) |
5. Core Performance Advantages
- Superior Corrosion Resistance: The Cr-Ni-N alloy system resists
general corrosion, pitting, and crevice corrosion in harsh
environments (e.g., seawater, acidic/alkaline solutions). Low
carbon content eliminates "sensitization" (carbide precipitation)
during welding, ensuring post-weld corrosion resistance.
- High Mechanical Strength: Nitrogen addition increases tensile
strength by ~15-20% compared to TP304L, allowing thinner walls for
weight/cost savings while maintaining pressure resistance.
- Excellent Ductility & Weldability: Low carbon and high nickel
content enable easy forming (bending, flanging) and welding via
TIG, MIG, or SMAW processes—no post-weld heat treatment required
for most applications.
- High-Temperature Stability: Withstands continuous service
temperatures up to 870°C (1600°F) and intermittent use up to 925°C
(1700°F) without significant oxidation or strength loss.
- Hygienic & Non-Toxic: Smooth surface finish (AP/BA) prevents
bacterial growth, meeting food-grade and pharmaceutical standards
(FDA-compliant).
6. Compliance with International Standards
All TP304LN seamless pipes adhere to globally recognized standards
for quality and safety:
- Material & Manufacturing: ASTM A312/A312M (USA), ASME B36.19M
(Stainless Steel Pipe), EN 10216-5 (European), JIS G3459 (Japan).
- Dimensional Tolerance: EN 10216-5 Class 2 (for OD and wall
thickness); ASME B36.19M for length and straightness.
- Non-Destructive Testing (NDT): 100% Ultrasonic Testing (UT) for
internal/external defects (per ASTM A578 Level A); Hydrostatic
Testing (per ASTM A312) at 3.45 MPa (500 psi) to ensure leak
tightness.
- Certifications: ISO 9001 (Quality Management), ISO 14001
(Environmental Management), PED 2014/68/EU (Pressure Equipment
Directive) for pressure applications.
7. Typical Applications
TP304LN seamless pipes are widely used across industries due to
their balanced performance:
- Oil & Gas: Offshore pipelines, wellhead equipment, and subsea
manifolds (resists seawater corrosion).
- Chemical & Petrochemical: Reactors, process pipelines, and storage
tanks (handles acids, alkalis, and organic solvents).
- Water Treatment: Desalination plants, wastewater treatment systems,
and potable water pipelines (resists chloride pitting).
- Food & Beverage: Dairy processing, brewing, and beverage conveyance
(hygienic, easy to clean).
- Pharmaceuticals: Pharmaceutical manufacturing equipment and sterile
fluid transfer (meets FDA/USP standards).
- Power Generation: Boiler feedwater lines, heat exchangers, and
turbine systems (high-temperature and pressure resistance).
- Construction: Architectural handrails, structural supports, and
decorative elements (aesthetic and weather-resistant).
8. Export Packaging & Shipping
To ensure product integrity during international transportation,
the pipes are packaged as follows:
- Inner Protection: Each pipe is wrapped in PE film to prevent
scratches, moisture, and contamination. For bright annealed (BA)
pipes, additional VCI (Volatile Corrosion Inhibitor) paper is used
to avoid rust.
- Bundling: Pipes are bundled into compact packs (10-15 pieces per
bundle, depending on DN) using galvanized steel straps (width:
32mm, thickness: 1.2mm) to prevent shifting.
- Palletization: Bundles are placed on wooden pallets (heat-treated,
ISPM 15-certified) to comply with international phytosanitary
requirements (avoids pest infestation).
- Outer Cover: Each pallet is covered with a heavy-duty PP woven bag
or waterproof tarpaulin to protect against rain, dust, and UV
radiation.
- Labeling: Clear labels are affixed to each bundle/pallet,
including: Product Name (TP304LN Seamless Pipe), DN/OD/Wall
Thickness/Length, Material Certificate No., Heat No., Quantity,
Weight, and Destination Port.
- Shipping: Compatible with container shipping (20ft/40ft containers)
or bulk cargo. Loading capacity: ~20-25 tons per 40ft container
(varies by DN and wall thickness).
9. Quality Assurance
Every batch of TP304LN seamless pipes undergoes strict quality
control:
- Incoming material inspection (chemical composition testing via /
Spectroscopy).
- Hot rolling and cold drawing process monitoring (dimensional
accuracy checks).
- Annealing and pickling process control (microstructure analysis via
metallography).
- 100% UT and hydrostatic testing.
- Final inspection (surface finish, straightness, and dimensional
verification).
- Material Certificate: Each shipment includes a MTC (Material Test
Certificate) per EN 10204 3.1/B, providing full traceability of
chemical composition, mechanical properties, and NDT results.
ASTM A312 309S SS Pipe DIN 1.4833 Seamless Stainless Steel Round Pipe
