Inconel 686 (UNS N06686) Seamless Pipe, High Performance Nickel Alloy, Excellent Resistance to Chloride & Mixed Acid for FGD, Petrochemical, Oil and Gas, Marine Service

ASTM B622 Inconel 686 Seamless Pipe

Inconel 686 (UNS N06686) is a high-performance nickel-chromium-molybdenum-tungsten alloy offering excellent resistance to corrosion, pitting, crevice corrosion, and stress corrosion cracking. It provides outstanding performance in aggressive acidic, chloride-containing, and highly corrosive environments, along with good mechanical properties and fabrication characteristics. Inconel 686 seamless pipes are widely used in chemical processing, petrochemical, oil and gas, marine engineering, flue gas desulfurization, waste treatment, and environmental protection industries.

Key Features and Advantages

• Excellent General Corrosion Resistance: Resists corrosion in oxidizing and reducing environments including mixed acids.

• Superior Resistance to Localized Corrosion: Great performance against pitting, crevice corrosion and chloride-induced SCC.

• Stable Corrosion Resistance After Welding: Low carbon design avoids harmful intergranular precipitation, no mandatory post-weld heat treatment.

• Good Weldability and Fabricability: Can be welded, bent and formed following standard nickel alloy working procedures.

• Reliable High-Temperature Corrosion Stability: Suitable for long-term service under elevated-temperature corrosive conditions.

Typical Applications

• Flue gas desulfurization scrubbers, ducts and waste gas treatment piping

• Chemical heat exchangers, reactors and piping for mixed acid, sulfuric and phosphoric acid

• Oil and gas sour service pipelines and high-chloride brine equipment

• Pulp and paper chlorine bleaching processing equipment

• Hazardous waste evaporators, seawater and marine corrosion piping systems

Technical Specifications

• Product Name: Inconel 686 Seamless Pipe

• Material Designation: UNS N06686

• Alloy Family: Nickel-Chromium-Molybdenum-Tungsten Corrosion Resistant Alloy

• Product Form: Seamless Tube / Pipe

• Reference Standard: ASTM B622, ASTM B829, NACE MR0175 (upon request)

• Outer Diameter: Custom sizes available

• Wall Thickness: Custom sizes available

• Length: Random lengths or fixed cut lengths as required

• Surface Condition: Pickled & bright annealed

• Inspection Documents: Material test certificates, PMI reports and NDT reports as agreed

Quality Assurance 

Products can be supplied according to agreed specifications, with chemical composition verification, mechanical testing, dimensional inspection, surface examination, PMI, NDT and material traceability where required. Material certificates and additional inspection documentation are available according to the purchase order and applicable product requirements.

Contact our sales team today for a competitive quote, technical datasheet, or to discuss your custom forging requirements.