1. Austenitic Stainless Steel
304/304L: Contains 18% chromium and 8% nickel, offering good general corrosion resistance. Widely used in food processing, architectural applications, and standard industrial piping.
304 Stainless Steel Pipe 304L stainless steel pipe316/316L: Enhanced with 2-3% molybdenum for superior chloride resistance, ideal for chemical plants, marine environments, and medical equipment.
316 Stainless Steel Tubing 316L Stainless steel pipe 316Ti Stainless steel pipe2. Martensitic Stainless Steel
410s: Features 11-13% chromium with low carbon content, balancing corrosion resistance and mechanical strength. Commonly used in structural components and high-temperature pipelines.
3. Duplex Stainless Steel
Duplex Stainless Steel PipeDuplex steels combine ferritic and austenitic phases (each ~30-50%), delivering high strength and corrosion resistance for harsh environments.
Key Characteristics
Chemistry: 18-28% chromium, 3-10% nickel, often with molybdenum (Mo) and nitrogen (N).
Mechanical Properties: Yield strength exceeds 485 MPa, far surpassing standard austenitic grades.
Corrosion Resistance: Excellent resistance to chloride stress corrosion, pitting, and crevice corrosion. PREN (Pitting Resistance Equivalent Number) ranges from 24 to >45.
Subcategories & Grades
Lean Duplex (PREN 24-25): UNS S32304. Cost-effective alternative to 304/316 for mild corrosive conditions.
Duplex 2304 PipeStandard Duplex (PREN 32-33): UNS S31803 (2205). Balances corrosion resistance (between 316L and high-molybdenum austenitic steels) and strength. Used in chemical processing and marine infrastructure.
Duplex 2205 pipeSuper Duplex (PREN 38-39): UNS S32550. Suitable for acidic environments with higher corrosion resistance than 22% Cr duplex grades.
Hyper Duplex (PREN >40): UNS S32750. Designed for extreme conditions (e.g., high chloride, elevated temperatures), common in oil and gas pipelines.
Super Duplex Pipe UNS S32750Applications
Chemical Industry: Acid-resistant equipment (e.g., for sulfuric acid handling).
Marine Engineering: Seawater desalination pipes, offshore platforms.
Energy Sector: Super duplex grades (e.g., S32750) for high-pressure oil/gas pipelines.
Material Selection Guidelines
Corrosion Exposure: Choose duplex grades (PREN ≥32) for chloride-rich or acidic environments.
Mechanical Demands: Opt for duplex or martensitic steels in high-stress applications (e.g., pressure vessels).
Stainless Steel Pipe SupplierCost Considerations: Duplex steels cost 2-3x more than austenitic grades (e.g., 2205 at
3,500/tonvs.304 at 1,100+/ton)
Stainless Steel Pipe Manufacturer
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