Low alloy steel-09CrCuSb (ND steel) for corrosive Resistant seamless steel tube.

1.Standard
Q/TDGG0039-2004
GB 150.2-2011
Corrosion Resistant Steel S-TEN 1 Tube 

JIS STANDARD
S-TEN1　⇒　JIS　G　3106　SM400
S-TEN2　⇒　JIS　G　3106　SM490A
2.Purpose
It is widely used in power plants and refineries to make the economizer, air preheater, heat exchanger and evaporator to resist the corrosion of sulfur containing flue gas.

3.Equivalent 

ND steel Equivalent to Corten steel 

4.Advantages

Weathering steel has many advantages over mild steel for structures that are outside and exposed to the elements.
Environment – weathers to natural brown which blends with the surrounding environment.
Strength – increased strength allows for weight savings vs mild carbon steel.
Cost savings – saves the cost of initially painting or coating the steel and the subsequent maintenance cost over its lifetime. Costs less than mild steel that has been coated.
Protection – develops its own protective coating which slows the rate of corrosion
Appearance – weathering steel changes and improves with age giving it great curbside appeal.

Mechanical properties of ND steel (09CrCuSb)

Tensile strength (Mpa):390-550
Yield strength (Mpa):≥245
Elongation (%):≥25

Chemical composition of ND steel (09CrCuSb)
C: ≤0.10
Si:0.20-0.40
Mn:0.35-0.65
Cr:0.70-1.20
Cu:0.25-0.45
Sb:≤0.10
S:≤0.10
P:≤0.10