Inconel 690 Manufacturer & Supplier | Export Worldwide

（Reliable Inconel 690 manufacturer from China. Full range of products, strict quality control, global shipping and OEM service.0

In Pressurized Water Reactor (PWR) nuclear power plants, nitric acid concentration units, and high-temperature alkaline evaporation systems, material reliability is non-negotiable. Inconel 690 (UNS N06690 / W.Nr. 2.4642)​ is a high-chromium (27–31%), austenitic, solid-solution strengthened nickel-iron-chromium alloy developed specifically to replace Alloy 600 in steam generator (SG) applications due to its inherent immunity to Primary Water Stress Corrosion Cracking (PWSCC) and superior resistance to caustic and oxidizing acid environments. Shanghai COCESS Special Alloys Co., Ltd​ operates as a direct manufacturer-source and global exporter of Inconel 690 plate, sheet, strip, round bar, forged billet, seamless tube, and welded pipe, fully compliant with ASTM B168, B166, B167, and ASME SB codes, with nuclear-grade melt control options and complete EN 10204 3.1 / 3.2 certification.

Chemical Composition & Metallurgical Advantage

The defining characteristic of UNS N06690 is its ~30% Chromium content, which promotes a tenacious, self-healing Cr₂O₃ passive film in high-temperature deaerated water and oxidizing acids. Unlike precipitation-hardenable alloys (e.g., Inconel 718), Inconel 690 is supplied in the solution-annealed condition​ (1040–1150°C rapid quench) and requires no aging.

Typical Chemistry (wt%, per ASTM B168 / ASME SB168):

• Nickel (Ni):​ 58.0 – 63.0 % (Balance / Matrix)

• Chromium (Cr):​ 27.0 – 31.0 % (Key: Forms robust Cr₂O₃ scale; eliminates PWSCC susceptibility)

• Iron (Fe):​ 7.0 – 11.0 % (Austenite stabilizer)

• Carbon (C):​ ≤ 0.05 % (Nuclear grade preferably ≤ 0.02 % to avoid sensitization)

• Manganese (Mn):​ ≤ 0.50 %

• Silicon (Si):​ ≤ 0.50 %

• Sulfur (S):​ ≤ 0.015 % (Premium nuclear grade ≤ 0.005 %)

• Copper (Cu):​ ≤ 0.50 %

• Cobalt (Co):​ ≤ 1.00 % (Often restricted to ≤ 0.05–0.10 % for PWR activated corrosion product control)

Mechanical Properties (Solution Annealed Condition)

• Tensile Strength (Rm):​ ≥ 620 MPa (90 ksi); typical 690–760 MPa

• Yield Strength (Rp0.2):​ ≥ 275 MPa (40 ksi); typical 300–345 MPa

• Elongation (A5):​ ≥ 35 % (typical 40–48 % — excellent for U-bending & tube expansion)

• Hardness:​ ≤ 100 HRB (≤ 220 HB)

• Density:​ 8.19 g/cm³ (0.296 lb/in³)

• Melting Range:​ 1349 – 1446 °C (2460 – 2635 °F)

• Service Temp (Structural / Corrosive):​ Continuous use from cryogenic to ~650°C load-bearing; oxidation-resistant to ~1150°C in static air.

Product Range & Export Forms

Shanghai COCESS maintains export-ready inventory and production capacity for the following Inconel 690 product forms:

• Condition:​ Solution annealed, descaled (pickled) or bright annealed (BA) for tube/sheet.

• Lengths:​ Standard 3–6 m random or fixed; coiled tubing available on request.

Quality Assurance & Nuclear-Grade Controls

Every export lot from Shanghai COCESS Special Alloys Co., Ltd​ is shipped with:

• EN 10204 3.1 Mill Test Report:​ Heat analysis, mechanical test results, grain size report, and heat treatment record. EN 10204 3.2 available upon request.

• NDE Options:

  • Plate: UT per ASTM A388 / SEB 682 / GB/T 4162 Class A or B

  • Tube: 100% Eddy Current Testing (ET per ASTM E426) + optional UT + hydrostatic/pneumatic test

  • Bar/Forgings: MT / PT as specified

• Elemental Controls for Nuclear Service:​ Low Cobalt (Co ≤ 0.05–0.10 %), Low Sulfur (≤ 0.005 %), low gas content (O/N/H) upon request; VIM+ESR melt route available for aerospace/nuclear critical parts.

• Dimensional Inspection:​ OD, WT, flatness, camber, and surface finish verified per order requirement.

• Third-Party Witness:​ SGS, TÜV, DNV, BV, ABS available.

OEM & Value-Added Services

To support international fabricators and EPC contractors, we provide:

• Precision Cutting:​ Plate water-jet / plasma profiling (CAD-based), bar saw cut-to-length, tube cut & chamfer.

• Pre-Machining:​ Rough turning of bar/forging O.D./I.D., face & drill center hole, tube end preparation.

• Heat Treatment:​ In-house solution annealing with full temperature-time chart documentation.

• Surface Finishing:​ Pickling, passivation, glass bead blasting.

• Packaging:​ Seaworthy export crating with interleaving paper/VCI protection; wooden skids for plate; coil eye-to-sky or eye-to-wall as required.

Typical Global Applications

• Nuclear Power (PWR):​ Steam Generator (SG) U-tubes, tube sheets, primary/secondary side piping cladding strip, nuclear auxiliary system fasteners.

• Chemical Processing:​ Nitric acid plants (concentration columns, absorption towers), mixed HNO₃/HF acid service, oxidizing waste heat recovery.

• Alkali Industry:​ High-temperature caustic (NaOH/KOH) evaporators, condensers, and transfer lines (resistant to caustic SCC).

• Flue Gas Desulfurization (FGD) & Waste Incineration:​ Components exposed to Cl⁻-containing acidic condensates where 300-series SS fails.

For Inconel 690 plate, tube (including SG U-tube stock), bar, or forged products — including current stock sizes, sample MTR, nuclear technical questionnaire response, or a formal quotation — please contact Shanghai COCESS Special Alloys Co., Ltd. Our technical and logistics team understands the additional documentation, elemental restrictions, and NDT rigor required for nuclear power and high-reliability energy equipment supply chains worldwide.

Website: https://en.cocessalloys.com
Email: sales@cocessalloys.com