ASTM A312 TP 347 ERW Pipes

ASTM A312 TP 347 ERW Pipes

ASTM A312 TP 347 ERW Pipes are niobium (columbium) stabilized austenitic stainless steel welded pipes designed for high-temperature service and resistance to intergranular corrosion. The addition of niobium stabilizes the structure and prevents carbide precipitation during welding and high-temperature exposure.

These pipes are widely used in petrochemical plants, power generation facilities, refineries, heat exchangers, and high-pressure systems where long-term thermal stability and corrosion resistance are essential.

Specifications

Standard	ASTM A312 / ASME SA312
Grade	TP 347
Manufacturing Process	Electric Resistance Welded (ERW)
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

• Niobium Stabilized: Prevents intergranular corrosion after welding.
• Excellent High-Temperature Strength: Suitable for elevated temperature applications.
• Improved Creep Resistance: Performs well in long-term thermal exposure.
• Superior Oxidation Resistance: Maintains performance in high-heat environments.
• Reliable Weldability: No need for post-weld heat treatment in most cases.

Chemical Composition (Typical)

Element	347 (%)
Carbon	0.08 Max
Chromium	17.0 – 19.0
Nickel	9.0 – 13.0
Niobium (Columbium)	10 x C Min – 1.0 Max

Applications

• Petrochemical Processing
• Power Generation Plants
• Heat Exchangers
• Boilers & Superheaters
• Refinery Equipment

Quality Testing

• Hydrostatic Testing
• Ultrasonic Testing (UT)
• Eddy Current Testing
• PMI Testing
• Dimensional Inspection

Conclusion

ASTM A312 TP 347 ERW Pipes offer excellent resistance to intergranular corrosion, superior high-temperature performance, and long-term structural stability, making them a dependable choice for demanding industrial applications.