Introduction to 304 stainless steel welded pipe

304 stainless steel welded pipe, commonly referred to as 304 welded pipe, is manufactured using premium-grade 304 stainless steel—a versatile and widely used stainless steel alloy known for its superior corrosion resistance compared to 200 series materials. With its high chromium and nickel content, 304 stainless steel forms a dense and stable oxide film on its surface, providing enhanced resistance to rust and corrosion.

Appearance & Structure of 304 Stainless Steel Welded Pipe

304 stainless steel welded pipes feature a smooth surface, uniform wall thickness, and high structural integrity. They are available in a wide range of diameters—from as small as 6mm up to 630mm, with custom options extending to a maximum of 1800mm. The wall thickness is also customizable, typically ranging between 1.2mm and 30mm, depending on specific application needs. These pipes are known for their precision, bright internal and external finish, and consistent dimensions, making them ideal for demanding industrial systems.

Key Performance Features of 304 Stainless Steel Welded Pipe

Excellent Corrosion Resistance
304 welded pipe offers outstanding resistance to oxidation and intergranular corrosion. It performs well in environments containing nitric acid (≤65% concentration below boiling point), alkalis, and a wide range of organic and inorganic chemicals.

High Temperature Tolerance
These pipes are capable of withstanding temperatures between 1000°C and 1200°C, making them suitable for high-temperature industrial applications.

High Mechanical Strength
With a minimum yield strength of 205 N/mm² and tensile strength of ≥520 N/mm², 304 welded pipe can resist high pressure and mechanical impacts.

Ease of Fabrication and Welding
304 stainless steel is known for its excellent formability and weldability. It supports multiple welding techniques, including manual arc welding, automated welding, and laser welding, making it adaptable to complex piping layouts.

Production Process of 304 Stainless Steel Welded Pipe

The manufacturing of 304 stainless steel welded pipes involves several key stages:

Pickling
Raw 304 stainless steel is pickled to remove surface oxides and contaminants, ensuring better weld quality.

Passivation
The material undergoes passivation treatment to create a protective oxide layer that boosts corrosion resistance.

Welding
The cleaned and passivated stainless steel is welded to form the pipe structure.

Cutting
The welded pipes are cut to the required lengths based on customer specifications.

Heat Treatment
Post-welding heat treatment is performed to relieve internal stresses and improve mechanical properties.

Straightening & Finishing
The pipes are corrected for roundness and straightness to meet strict dimensional tolerances.

Applications of 304 Stainless Steel Welded Pipe

Due to its durability, hygiene, and resistance to corrosion and temperature, 304 stainless steel welded pipe is used across a wide range of industries:

Petrochemical Industry – For conveying corrosive fluids such as acids, alkalis, and salts.

Food Processing – Ideal for sanitary pipeline systems due to its clean surface and corrosion resistance.

Building Plumbing – Commonly used in water supply and drainage systems.

Machinery Manufacturing – Suitable for structural components and mechanical parts.

Other Sectors – Also applied in electricity, metallurgy, HVAC, gas supply, water treatment, and the manufacture of vehicles like ships, aircraft, and automobiles.

Maintenance & Care of 304 Stainless Steel Welded Pipe

To ensure optimal performance and longevity of 304 stainless steel welded pipes, regular maintenance is recommended:

Routine Inspection – Check for signs of surface damage, rust, or weld defects.

Cleaning – Periodically clean internal and external surfaces to remove oil, dust, or chemical residues.

Optional Anti-Corrosion Treatment – For harsher environments, protective coatings can be applied to further enhance corrosion resistance.

Conclusion

304 stainless steel welded pipe stands out for its excellent corrosion resistance, high strength, and versatility across industries. With proper selection, installation, and maintenance, it ensures reliable, long-term service in even the most demanding environments.