Duplex Stainless Steel Pipe

Duplex stainless steel pipe always applied in harsh environment, like low temperature, high temperature and corrosion situation, due to their special properties, high strength and excellent corrosion resistance are duplex steel key advantages.

Duplex stainless steel pipe has many advantages compared with other stainless steels pipe, so they are used more and more wide for many industries, our duplex stainless steel pipe specifications include ASTM A789 and A790 for general service, both seamless and welded type, duplex 2205 stainless steel is the most used grade.

Duplex Stainless Steel

Duplex Stainless Steels are characterized by Austenitic stainless steels and Ferritic stainless steels, high chromium (18–30%) and molybdenum (up to 5%) and lower nickel contents (3% – 10%) than Austenitic stainless steels, there are Lean Duplex, Standard Duplex, Super Duplex, Hyper Duplex.

Common Duplex Stainless Steel Grades

  • S32101
  • S32202
  • S32304
  • S31803
  • S32205
  • S32750
  • S32760
  • S32707
  • S33207

Duplex stainless steel have Austenitic and Ferritic stainless steel microstructure, and possess properties in two groups stainless steel, however, there are different.

Corrosion Resistance

Duplex stainless steel are extremely corrosion resistant, including intergranular corrosion and stress corrosion cracking.

Heat Resistance

Duplex steel grades have a good performance in high temperature, and can be used down to at least -50°C low temperature, better ductility than the ferritic and martensitic grades.

Heat Treatment

Solution temperature is around 1100°C, and rapid cooling.

Duplex Stainless Steel Pipe Applications

Due to duplex stainless steel excellent corrosion resistance and high strength, duplex stainless steel pipe and tube are applied in harsh environments, even in chloride and sulphide environments.

Duplex stainless steel pipe are typically used in:

  • Chemical processing, transport and storage
  • Oil and gas exploration and offshore rigs
  • Oil and gas refining
  • Marine environments
  • Pollution control equipment
  • Pulp & paper manufacturing
  • Chemical process plant
duplex stainless steel pipe

Duplex Stainless Steels Chemical Composition

Designation Chemical composition % by mass max
UNS No AISI C Si Mn P S Cr Mo Ni Others
S32101 LDX 2101 0.040 1.00 4.0/6.0 0.040 0.030 21.0/22.0 0.10/0.80 1.35/1.70 N 0.20/0.25; Cu 0.10/0.80
S32202 DX 2202 0.030 1.00 2.00 0.040 0.010 21.5/24.0 0.45 1.00/2.80 N 0.18.0.26
S32205 2205 0.030 1.00 2.00 0.030 0.020 22.0/23.0 3.0/3.5 4.5/6.5 N 0.14/0.20
S32304 2304 0.030 1.00 2.50 0.040 0.030 21.5/24.5 0.05/0.60 3.0/5.5 N 0.05/0.20; Cu 0.05/0.60
S32404 Uranus 50 0.04 1.0 2.0 0.030 0.010 20.5/22.5 2.0/3.0 5.5/8.5 N 0.20; Cu 1.0/2.0
S32520 Uranus 52N+ 0.030 0.80 1.50 0.035 0.020 24.0/26.0 3.0/4.0 5.5/8.0 N 0.20/0.35; Cu 0.50/2.00
S32550 Ferralium 255 0.04 1.00 1.50 0.040 0.030 24.0/27.0 2.9/3.9 4.5/6.5 N 0.10/0.25; Cu 1.50/2.50
S32750 2507 0.030 0.80 1.20 0.035 0.020 24.0/26.0 3.0/5.0 6.0/8.0 N 0.24/0.32; Cu 0.50
S32760 Zeron 100 0.030 1.00 1.00 0.030 0.010 24.0/26.0 3.0/4.0 6.0/8.0 N 0.20/0.30; Cu 0.5/1.00; W 0.50/1.00