SUS304 Stainless Steel Welded Pipe: Overview and Applications SUS304 stainless steel welded pipe is a widely used austenitic stainless steel product known for its excellent corrosion resistance, durability, and versatility. Composed primarily of chromium (18–20%) and nickel (8–10.5%), along with small amounts of carbon, manganese, and silicon, SUS304 offers a balanced combination of mechanical properties and weldability, making it suitable for various industrial and commercial applications. Manufacturing Process SUS304 welded pipes are produced by forming stainless steel coils or sheets into a cylindrical shape and then welding the seam using high-frequency induction welding (HFIW), tungsten inert gas (TIG) welding, or laser welding. The welded area is often heat-treated or cold-worked to enhance strength and corrosion resistance. Post-weld processes like pickling, passivation, or polishing may be applied to improve surface finish and remove oxidation. Key Properties 1. Corrosion Resistance: SUS304 exhibits strong resistance to oxidation, acids, and alkalis, making it ideal for environments exposed to moisture or chemicals. Its chromium content forms a passive oxide layer that protects against rust. 2. High-Temperature Performance: With good thermal stability, SUS304 can withstand temperatures up to 870°C (1600°F) intermittently and 925°C (1697°F) under controlled conditions. 3. Mechanical Strength: It offers moderate tensile strength (≥520 MPa) and elongation (≥40%), ensuring durability under stress. 4. Hygienic & Aesthetic Qualities: Its smooth surface resists bacterial growth and is easy to clean, making it suitable for food processing, pharmaceuticals, and architectural applications. Applications - Industrial: Used in chemical processing, oil & gas, and power plants for piping systems, heat exchangers, and exhausts. - Food & Beverage: Preferred for dairy, brewing, and food handling equipment due to its non-reactive nature. - Architecture & Construction: Applied in handrails, structural supports, and decorative elements for its sleek appearance. - Automotive & Aerospace: Utilized in exhaust systems and fluid transport components. Advantages Over Seamless Pipes Welded pipes are more cost-effective for large-scale production while maintaining comparable performance in low-to-medium pressure applications. However, seamless pipes may be preferred for high-pressure or extreme conditions due to their uniform structure. Standards & Certifications SUS304 pipes comply with international standards such as ASTM A312, JIS G3459, and EN 10217-7, ensuring quality and consistency. In summary, SUS304 stainless steel welded pipes are a reliable, economical solution for industries requiring corrosion-resistant, high-strength, and aesthetically pleasing piping systems. Their adaptability across diverse sectors underscores their importance in modern engineering and manufacturing.