ASTM A312 TP 347H Seamless Pipes

ASTM A312 TP 347H Seamless Pipes

ASTM A312 TP 347H Seamless Pipes are high carbon, niobium (columbium) stabilized austenitic stainless steel pipes designed for superior high-temperature strength and resistance to intergranular corrosion. Manufactured without welded seams, these pipes provide excellent structural integrity for critical applications.

Grade 347H offers improved creep resistance and enhanced mechanical properties at elevated temperatures compared to standard 347 grade, making it ideal for heat-intensive industrial environments.

Specifications

Standard	ASTM A312 / ASME SA312
Grade	TP 347H
Manufacturing Process	Hot Rolled / Cold Drawn Seamless
Size Range	1/8" NB to 24" NB
Wall Thickness	Schedule 5S to Schedule XXS
Length	6 Meters Standard / Custom Length
Surface Finish	Annealed & Pickled, Polished, Bright Finish
End Type	Plain End, Beveled End, Threaded

Key Benefits

• Enhanced High-Temperature Strength: Improved creep resistance for elevated temperature service.
• Intergranular Corrosion Resistance: Niobium stabilization prevents carbide precipitation.
• Excellent Oxidation Resistance: Performs reliably in heat-exposed environments.
• Strong Mechanical Properties: Seamless construction ensures durability under pressure.
• Long Service Life: Suitable for continuous high-temperature operations.

Chemical Composition (Typical)

Element	347H (%)
Carbon	0.04 – 0.10
Chromium	17.0 – 19.0
Nickel	9.0 – 13.0
Niobium (Cb)	10 x C Min

Applications

• Heat Exchangers
• Boilers and Pressure Vessels
• Petrochemical Processing Units
• Oil & Gas Industry
• Power Generation Plants
• High-Temperature Piping Systems

Quality Testing

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

Conclusion

ASTM A312 TP 347H Seamless Pipes provide enhanced high-temperature strength and excellent resistance to intergranular corrosion. Their niobium-stabilized, high-carbon composition and seamless construction ensure reliable performance in demanding industrial piping systems.