What is the difference between SA 240 304 and 304l?

What is the Difference Between SA 240 304 and 304L Stainless Steel?

Introduction to SA 240 304 and 304L

SA 240 304 and 304L are both grades of austenitic stainless steel under the ASME SA240 specification for chromium-nickel stainless steel plates, sheets, and strips used in pressure vessels and general applications. These materials are widely used in industries like chemical processing, food production, and construction due to their corrosion resistance and strength. The primary difference lies in their carbon content, which affects weldability and susceptibility to intergranular corrosion.

SA 240 304 is the standard grade, while 304L is the low-carbon variant designed for better performance in welded structures. Gangsteel, a leading manufacturer and exporter in China, supplies both grades compliant with ASME SA240. As experts in ASME SA240 stainless steel plates, Gangsteel offers customized solutions for global clients. This article explains the key differences between SA 240 304 and 304L, including composition, properties, and applications.

Chemical Composition Differences

The main distinction between SA 240 304 and 304L is the carbon content. Lower carbon in 304L prevents carbide precipitation during welding, reducing the risk of corrosion. The table below compares their compositions as per ASME SA240:

Gangsteel ensures low impurities in both for enhanced performance.

Mechanical Properties Comparison

SA 240 304 has slightly higher strength due to its carbon content, while 304L prioritizes weldability. The table below summarizes properties as per ASME SA240:

These make 304 suitable for higher-strength needs, 304L for corrosion-sensitive welds.

Corrosion Resistance: SA 240 304 vs 304L

Both have good general corrosion resistance (PREN ~19), but SA 240 304L is superior in welded areas, resisting intergranular corrosion per ASTM A262. SA 240 304 may experience corrosion in HAZ without annealing.

Weldability and Formability

SA 240 304L is better for welding due to low carbon, avoiding sensitization without annealing. SA 240 304 may require annealing after welding. Formability is excellent for both.

Applications of SA 240 304 and 304L

The table below highlights applications:

Gangsteel’s ASME SA 213/SA 213M stainless pipes pair with both.

Comparing SA 240 304 and 304L with Other Grades

SA 240 304/304L vs 316: Both for general use, but 316 has molybdenum for chloride resistance.

SA 240 304/304L vs 201: 304/304L has higher nickel for better corrosion, 201 is cheaper.

SA 240 304/304L vs 430: 304/304L is non-magnetic with better formability, 430 is magnetic and cheaper for mild use.

Gangsteel’s nickel alloy steel plates offer advanced options.

Why Choose Gangsteel for SA 240 304 and 304L?

Gangsteel provides both with:

• Quality Assurance: Compliant with ASME SA240 and ASTM A240.
• Customization: Various sizes and finishes.
• Export Excellence: Worldwide delivery.
• Variety: Including SA240 Gr 347 and SA240 Gr 201L.

Conclusion

SA 240 304 and 304L provide strength and corrosion resistance for various applications, with 304L better for welding. Supported by equivalents like EN 1.4301. Gangsteel’s solutions in China, including SA240 Gr 316L and SA240 Gr 904L, ensure quality. Contact Gangsteel for UNS stainless steel plates to meet your needs.