Alloy 20 Flanges

Alloy 20 Flanges for reliable pipe-to-pipe and pipe-to-equipment joints, available on MetalMitra in all standard face types and pressure classes to ASTM B 564 / ASME SB 564, with mill-certified traceability on every lot.

Alloy 20 Flanges are forged or machined components used to connect pipes, valves, pumps and equipment, allowing easy assembly, inspection and maintenance of piping systems.

Alloy 20 (UNS N08020) was developed specifically to stand up to sulphuric acid. Alloy 20 (UNS N08020) is a niobium-stabilized nickel-iron-chromium alloy with copper and molybdenum, developed for excellent resistance to sulphuric acid and other aggressive chemical environments.

Product range

• Weld Neck Flanges — Butt-welded flanges for high-pressure and high-temperature service.
• Slip On Flanges — Slip over the pipe for easy alignment and welding.
• Blind Flanges — Solid flanges used to close pipe ends and openings.
• Socket Weld & Threaded Flanges — Compact connections for smaller bore piping.
• Lap Joint Flanges — Used with stub ends for easy alignment.
• Spectacle & RTJ Flanges — Positive isolation and high-pressure sealing.

Why engineers choose it

• Sulphuric Acid Resistance — Developed specifically for sulphuric acid service.
• Stress Corrosion Resistance — Good resistance to chloride stress corrosion cracking.
• Niobium Stabilized — Reduced risk of carbide precipitation during welding.
• Good Fabricability — Forms, machines and welds without fuss.

Where it is used

• Chemical Processing
• Sulphuric Acid Plants
• Pharmaceutical
• Petrochemical
• Pickling Equipment
• Food Processing
• Synthetic Fibre Plants
• Heat Exchangers
• Process Piping
• Storage Tanks
• Fabrication
• General Engineering

Inspection & paperwork

Suppliers on MetalMitra back Alloy 20 Flanges with the checks and paperwork your QA team expects.

• Dimensional inspection
• Visual and surface inspection
• Grade verification against the order
• Chemical composition verification
• Mechanical testing as applicable
• Flange face and bolt-hole inspection
• Non-destructive testing as applicable
• EN 10204 3.1 Mill Test Certificate
• Third-party inspection (TPI) on request

The MetalMitra advantage

• Checked sellers only — Every supplier profile is screened by MetalMitra before it goes live.
• Faster sourcing — Post one requirement and receive competitive offers without chasing calls.
• Paperwork sorted — MTC 3.1, test reports and TPI arranged as your project demands.
• Global logistics — Seaworthy packing and dispatch to project sites across the world.

Get a quote

Tell us the specification, quantity and destination you need for Alloy 20 Flanges. MetalMitra connects you with suppliers who can deliver.

Technical note: Figures shown are indicative. Final acceptance should be based on the applicable standard, approved drawings and the MTC supplied with the material.