Products Description
The 09CrCuSb tube, also known as ND alloy steel pipe, is a low-alloy corrosion-resistant steel widely utilized in air preheaters, economizers, heat exchangers, and evaporators operating in high-sulfur flue gas environments.
It effectively resists sulfuric acid dew point corrosion and acid condensation corrosion in power plants, refineries, and petrochemical industries.
This ND low-alloy structural steel was developed specifically for environments exposed to sulfuric acid dew point conditions. It is produced using ultra-high-power electric furnace smelting, followed by ladle refining and vacuum degassing, ensuring high purity and stable composition.
During service, the alloy forms a compact passivation layer enriched with chromium (Cr), copper (Cu), antimony (Sb), and titanium (Ti). This dense protective film significantly enhances corrosion resistance and ensures long-term durability.
Compared to conventional steels such as carbon steel, Corten steel, or CR1A, ND steel demonstrates superior corrosion resistance, mechanical strength, and oxidation resistance, making it a preferred material for acidic and flue gas systems.
Key Features
Excellent resistance to sulfuric acid dew point corrosion (below 200°C).
Superior mechanical performance compared to carbon steel and Corten steel.
Stable protective oxide layer due to Cr–Cu–Sb synergy.
Good weldability without the need for preheating or post-weld heat treatment.
Long service life and cost-effective alternative to stainless steel in flue gas systems.
Chemical Composition (Typical Values)
| Grade | C (%) | Si (%) | Mn (%) | Cr (%) | Cu (%) | Sb (%) | P (%) | S (%) |
|---|---|---|---|---|---|---|---|---|
| 09CrCuSb (ND Steel) | ≤0.10 | 0.20–0.40 | 0.35–0.65 | 0.70–1.20 | 0.25–0.45 | ≤0.10 | ≤0.10 | ≤0.03 |
According to GB150.2-2011 Appendix A.3.5:
| Grade | C (%) | Si (%) | Mn (%) | Cr (%) | Cu (%) | Sb (%) | P (%) | S (%) |
|---|---|---|---|---|---|---|---|---|
| 09CrCuSb (ND Steel) | ≤0.12 | 0.20–0.40 | 0.35–0.65 | 0.70–1.10 | 0.25–0.45 | 0.04–0.10 | ≤0.030 | ≤0.020 |
Mechanical Properties
| Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) |
|---|---|---|---|
| 09CrCuSb (ND Steel) | 390–550 | ≥245 | ≥25 |
