ASTM A358 EFW 321 Pipes

ASTM A358 EFW 321 Pipes

ASTM A358 EFW 321 Pipes are titanium-stabilized austenitic stainless steel pipes manufactured using the Electric Fusion Welding (EFW) process. The addition of titanium improves resistance to intergranular corrosion, especially after welding or exposure to elevated temperatures.

Grade 321 is particularly suitable for high-temperature applications where resistance to carbide precipitation is essential. These pipes are widely used in heat exchangers, boilers, and high-temperature industrial systems.

Specifications

Standard	ASTM A358 / ASME SA358
Grade	321
UNS Number	S32100
Manufacturing Process	Electric Fusion Welded (EFW)
Size Range	1/2" NB to 24" NB
Wall Thickness	Schedule 5S to Schedule 80S
Length	6 Meters Standard / Custom Length
Surface Finish	Annealed & Pickled, Polished, Matte Finish
End Type	Plain End, Beveled End, Threaded

Key Benefits

• Excellent High-Temperature Resistance: Performs well in continuous high-heat environments.
• Resistance to Intergranular Corrosion: Titanium stabilization prevents carbide precipitation.
• Reliable Welded Construction: EFW process ensures strong and consistent seam quality.
• Good Oxidation Resistance: Suitable for elevated temperature service conditions.
• Long Service Life: Durable performance in demanding industrial systems.

Chemical Composition (Typical)

Element	321 (%)
Carbon	0.08 Max
Chromium	17.0 – 19.0
Nickel	9.0 – 12.0
Titanium	5x(C+N) Min – 0.70 Max

Applications

• Heat Exchangers
• Boilers & Superheaters
• Oil & Gas Processing
• Power Generation Plants
• High-Temperature Chemical Equipment

Quality Testing

• Hydrostatic Testing
• Ultrasonic Testing (UT)
• Radiographic Testing (RT)
• PMI Testing
• Dimensional Inspection

Conclusion

ASTM A358 EFW 321 Pipes provide reliable high-temperature performance, excellent weld stability, and strong resistance to intergranular corrosion. Their titanium-stabilized composition makes them a preferred choice for demanding thermal and industrial applications.