ASME SB464 / ASTM B464 Alloy 20 Pipe Welded UNS N08020 Alloy Pipe for Oil and Gas Industry
ASTM B464 Alloy 20 Welded Pipe Welded UNS N08020 Alloy Pipe Solution Annealed
ASTM B464 Alloy 20 Pipe Welded UNS N08020 Alloy Pipe Solution Annealed Pipe means a welded pipe made from Alloy 20 / UNS N08020 according to ASTM B464/B464M, supplied in the solution-annealed condition. It is an austenitic nickel-iron-chromium-molybdenum-copper alloy pipe with a longitudinal weld seam, heat-treated after welding to restore corrosion resistance and ductility.
Key characteristics of Alloy 20 pipe
-
Excellent resistance to sulfuric acid
-
Good resistance to phosphoric acid, nitric acid, and organic acids
-
Resistant to chloride stress corrosion cracking
-
Good pitting and crevice corrosion resistance
-
Austenitic structure — non-magnetic in the annealed condition
-
Good formability and weldability
-
Suitable for moderate-to-high temperature corrosive service
Equivalent Grade of ASTM B464 Alloy 20 Pipe Welded UNS N08020 Alloy Pipe
| STANDARD | UNS | WERKSTOFF NR. | AFNOR | EN |
| Alloy 20 | N08020 | 2.4660 | Z2NCUD31-20AZ | NiCr20CuMo |
Chemical Properties % of ASTM B464 Alloy 20 Welded Pipe Welded UNS N08020 Alloy Pipe
| Element | Ni | Cr | Fe | Mo | Cu | N | C | Mn | Si | S | P | Nb |
|
UNS N08020 (Alloy 20) |
32.0 - 38.0 | 19.0 - 21.0 | Balance | 2.0 - 3.0 | 3.0 - 4.0 | 0.045 | 0.07 | 2.0 | 1.0 | 0.035 | 0.045 |
0.035 |
Mechanical Properties of ASTM B464 Alloy 20 Pipe Welded UNS N08020 Alloy Pipe (Solution-Annealed Condition)
| Grade |
Tensile Strength, min (MPa) |
Yield Strength (0.2% offset), min (MPa) | Elongation in 2 in. (50 mm), min (%) | Hardness, max (HB) |
|---|---|---|---|---|
| UNS N08020 (Alloy 20) | 550 | 240 | 30 | 217 |
For UNS N08020 / Alloy 20 welded pipe, solution annealing is usually performed at:
-
1725–1850°F / 940–1010°C
-
Followed by rapid quench, usually water quenching.
Purpose:
-
Dissolves carbides and other precipitates.
-
Homogenizes the weld and heat-affected zone.
-
Restores ductility and toughness.
-
Maximizes corrosion resistance.
-
Relieves residual stresses from forming and welding.
Application
-
Chemical processing plants
-
Oil and Gas Industry
-
Sulfuric acid and phosphoric acid production
-
Fertilizer production
-
Pickling lines
-
Heat exchangers and condensers
-
Petrochemical piping
-
Pulp and paper processing
-
Food processing
-
Pollution control equipment
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.