Stainless Steel Pipes | High-Pressure 347H/904L Seamless Design

Stainless Steel Pipes | High-Pressure 347H/904L Seamless Design

Technical Specifications

Key Attributes

1. High-Pressure Performance

   • 347H: Stabilized with niobium to prevent carbide precipitation during welding, ideal for stainless steel pipe fittings near me in power plants and oil refineries. Withstands pressures up to 40 MPa in superheater systems.
   • 904L: High molybdenum (4–5%) and copper (1–2%) content ensures resistance to sulfuric and phosphoric acids, making it suitable for stainless steel pipe screens in chemical processing and marine environments.

2. Mechanical Strength

   • Tensile Strength: 347H achieves up to 750 MPa, outperforming standard 304/316L grades in high-temperature steam pipelines. 904L balances strength and ductility (45% elongation) for cold forming in complex stainless steel pipe vs copper plumbing retrofits.
   • Bend Strength: Both grades support cold bending up to 180° without cracking, critical for custom stainless steel pipe fittings near me installations.

3. Versatility

   • 347H: Used in boilers, heat exchangers, and stainless steel pipe screens for high-temperature filtration.
   • 904L: Ideal for seawater desalination, pharmaceutical reactors, and stainless steel pipe vs copper plumbing systems requiring non-reactive surfaces.

Weight Calculation

The weight of stainless steel pipes is calculated using:
Weight (kg/m)=1000(OD−WT)×WT×0.02466
Where:

• $OD$: Outer Diameter (mm)
• $WT$: Wall Thickness (mm)

Example: A stainless steel pipe vs copper plumbing retrofit using 347H (100 mm OD, 5 mm WT) weighs 11.69 kg/m, 40% lighter than copper alternatives.

Identification & Marking

• Laser Etching: ASTM/EN standards, heat number, and grade (e.g., "S34709" or "N08904").
• Color Coding: Optional bands for rapid identification in industrial inventory systems.

Why Do Stainless Steel Pipes Rust?

Despite their corrosion-resistant properties, rust can occur due to:

1. Chloride Exposure: Coastal environments or de-icing salts degrade passive oxide layers, particularly in welded stainless steel pipe fittings near me without post-weld pickling.
2. Intergranular Corrosion: Improper welding of 347H without niobium stabilization leads to chromium carbide formation at grain boundaries.
3. Surface Contamination: Iron particles from cutting tools or grease disrupt the protective layer, a critical consideration for stainless steel pipe screens in hygienic industries.
4. Galvanic Corrosion: Direct contact with copper in stainless steel pipe vs copper plumbing systems accelerates oxidation. Insulating gaskets or coatings mitigate this risk.

Applications

• 347H: Boiler tubes, radiant superheaters, and stainless steel pipe fittings near me in nuclear reactors.
• 904L: Sulfuric acid storage tanks, seawater desalination plants, and stainless steel pipe screens for pharmaceutical filtration.

Why Choose Our Stainless Steel Solutions?

1. ISO 9001-Certified Quality: Strict adherence to ASTM/EN standards, validated by SGS/TUV certifications.
2. Custom Fabrication: Tailored stainless steel pipe fittings near me and stainless steel pipe screens with precision-cut dimensions and surface finishes.
3. Global Inventory: 10,000+ tons of 347H/904L pipes in stock, ready for urgent stainless steel pipe vs copper plumbing projects.
4. Technical Expertise: 25+ years of metallurgical support, including welding guides and corrosion prevention strategies.
5. Sustainability: 100% recyclable materials with 50+ year lifespans, reducing lifecycle costs and environmental impact.