ASTM B444 Nickel Alloy 625 Seamless Pipe | ASTM B444 | UNS N06625 | Inconel 625

Shaanxi Shangyou Stainless Steel Co., Ltd. supplies Nickel Alloy 625, also known as Inconel 625, identified as UNS N06625 and Werkstoff 2.4856, in seamless pipe and tube form according to ASTM B444 / ASME SB-444 . Our seamless pipe products meet the general requirements covered by ASTM B829 and are available in both Grade 1 (annealed) and Grade 2 (solution annealed) heat-treated conditions .

Nickel Alloy 625 is a nickel-chromium-molybdenum alloy with an addition of niobium (3.15-4.15%) that provides high strength without the need for a strengthening heat treatment . The alloy resists a wide range of severely corrosive environments and is especially resistant to pitting and crevice corrosion, with high strength and toughness from cryogenic temperatures to 1,800°F (982°C) . Typical applications include chemical processing, aerospace, marine engineering, pollution control equipment, and nuclear reactors .

Composition per ASTM B444 requirements.

Actual properties depend on product form, dimensions, and heat-treatment condition.

Grade 1 (Annealed)

Material is normally employed in service temperatures up to 1,100°F (593°C) . The annealed condition provides excellent corrosion resistance and ductility while maintaining high strength.

Grade 2 (Solution Annealed)

Material is normally employed in service temperatures above 1,100°F (593°C) when resistance to creep and rupture is required . The solution annealed condition is recommended for high-temperature applications where creep performance is critical.

Caution on Brittleness: Hot-working or reannealing may change properties significantly, depending on working history and temperatures .

Alloy 625 seamless pipe offers outstanding resistance to a wide range of corrosive environments, making it ideal for marine, chemical, and oil and gas applications .

Key Corrosion Characteristics:

• Excellent resistance to pitting and crevice corrosion
• Resistance to chloride stress corrosion cracking
• Excellent resistance to seawater and salt solutions
• Good resistance to mineral acids: phosphoric, sulfuric, hydrochloric acid, and mixtures
• Resistance to alkalis and organic acids
• Good oxidation resistance up to 982°C
• Non-magnetic austenitic structure
• NACE MR0175 / ISO 15156 compliant for sour-service applications when properly processed

Selection Considerations:

• For applications above 593°C, Grade 2 (solution annealed) is recommended
• Suitable for subsea and offshore oil and gas applications
• Excellent for high-pressure equipment such as pumps and valves
• Final selection must consider the specific medium, concentration, temperature, and pressure conditions

• Chemical Processing: Reactors, heat exchangers, piping for aggressive acid environments
• Offshore and Marine: Seawater piping systems, marine components, desalination equipment
• Oil and Gas: High-pressure piping, subsea production systems, risers, cladding
• Aerospace: Turbine components, engine parts
• Environmental Technology: Flue gas desulfurization, waste incineration systems
• Nuclear: Reactor components, radioactive waste treatment

Available quality-control services include:

• Heat-number traceability
• Chemical composition verification
• Tensile, yield and elongation testing
• Hardness inspection
• Dimensional and surface inspection
• Positive Material Identification (PMI)
• Hydrostatic testing
• Nondestructive electric testing
• Heat-treatment records
• EN 10204 3.1 material certificate

For an accurate quotation, please provide:

Alloy Grade · Standard · Product Form · OD · Wall Thickness / Schedule · Length · Grade (1 or 2) · Quantity · Inspection Requirement · Application · Working Temperature · Destination Port

For corrosive or high-temperature environments, also provide:

Chemical Medium · Concentration · Temperature · Pressure · Oxidizing or Reducing Conditions

• Request ASTM B444 Alloy 625 Pipe Quote
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ASTM B444 Alloy 625 seamless pipe is a nickel-chromium-molybdenum-niobium alloy pipe (UNS N06625) with high strength, excellent pitting and crevice corrosion resistance, and toughness from cryogenic to 982°C .

The UNS designation is N06625; the European Werkstoff number is 2.4856; the EN material symbol is NiCr22Mo9Nb.

Grade 1 is annealed and used for service temperatures up to 593°C. Grade 2 is solution annealed and used for service above 593°C where creep and rupture resistance are required .

Stock sizes range from 1/2" to 4" OD with Schedule 10 through Schedule 80 wall thickness, with custom sizes available up to 40" OD .

No. Alloy 625 is not age-hardenable. High strength is achieved through solid solution strengthening. The material is supplied in either annealed (Grade 1) or solution annealed (Grade 2) condition .

It resists pitting, crevice corrosion, chloride stress corrosion cracking, seawater, mineral acids (phosphoric, sulfuric, hydrochloric), alkalis, organic acids, and oxidation up to 982°C .

Yes. Alloy 625 is highly suitable for seawater piping, offshore platforms, subsea equipment, and marine components due to its excellent corrosion resistance in marine environments .

Yes. Alloy 625 is approved for sour-service applications per NACE MR0175 / ISO 15156 when properly processed and certified .

Yes. Alloy 625 exhibits excellent weldability with good resistance to intergranular attack. Welding should be performed using qualified welding procedures.

Please provide the standard (ASTM B444), product form (seamless pipe), OD/wall thickness or schedule, Grade (1 or 2), quantity, inspection requirements, application, working temperature and destination port. For corrosive service, also specify the chemical medium and concentration.