Plate, Pipe, Tube & Bar | ASTM A240 / A312 / A479
Niobium-stabilized stainless steel for high-temperature, high-pressure applications. Available globally from China, Europe, and UAE.
Updated: July 2025
Product Form Minimum Order
** Trial orders available for EPC and industrial users – subject to lead time & surcharge.
Includes Free Pre-Shipment Third-Party Inspection (PMI, Dimensional, Visual, Photos) by SGS / TÜV
We don’t just sell certified material. We re-certify it ourselves and then have an independent expert verify it. This is our definition of uncompromising integrity.
Forms: Plate / Seamless Pipe / Welded Pipe / Round Bar / Tube
Standards: ASTM A240, A312, A479
UNS: S34700
W.Nr.: 1.4550
It’s ideal for high-temperature applications like heat exchangers, refinery piping, and exhaust systems where resistance to intergranular corrosion is essential.
Unlike 304/316, 347 is stabilized with niobium to prevent carbide precipitation during welding or thermal cycling — making it superior in high-temperature welded structures.
Yes. Thanks to niobium stabilization, 347 can be welded with minimal risk of intergranular corrosion. No post-weld heat treatment is usually needed.
Yes, when supplied in accordance with ASTM and ASME specs, 347 is approved for pressure vessels operating at elevated temperatures.
347H has higher carbon content, improving its strength at elevated temperatures. Use 347H in sustained high-temp pressure systems; 347 for general HT service.
• EN 10204 3.1 MTC
• TPI Accepted: SGS, BV, TUV
• ASME Boiler Code available on request
** Full traceability & documentation for EPC / refinery / pressure service
Stainless Steel 347 – Stable Performance at High Temperatures
Niobium-stabilized stainless for excellent intergranular corrosion resistance and high-temperature strength. Preferred in refinery and thermal systems.
• For elevated temperature & pressure vessels
• Niobium-stabilized for carbide control during welding
• For high-temp pipelines and refinery systems
• Requires hydrotest & NDT
• Used in heat exchangers, bolting, and structural parts
• Supplied annealed – hot or cold finished
