ASTM B668 UNS N08028 Pipe Manufacturer
We are a leading manufacturer, supplier, and exporter of ASTM B668 UNS N08028 pipes, delivering high-quality nickel-iron-chromium-molybdenum-copper alloy pipes to industries worldwide. Alloy UNS N08028, also known as Alloy 28, is a corrosion-resistant austenitic alloy designed to withstand strong acids, seawater environments, and aggressive chemical media. Our ASTM B668 pipes are manufactured with strict quality control and tested to meet international standards.
ASTM B668 UNS N08028 Tube Specification
Standard: ASTM B668 / ASME SB668
Material Grade: UNS N08028
Trade Name: Alloy 28 (often called “Sanicro 28”)
Product Form: Seamless / Welded Tubes
ASTM B668 standard Specification for UNS N08028 and N08029 Seamless Pipe and Tube
This specification covers the standard requirements for UNS N08028 seamless cold-finished or hot-finished pipe and tube intended for general corrosive services. The pipe and tube shall be furnished in the solution-annealed condition and heat treated at a certain range of temperature by subsequent quenching in water or rapidly cooling by other means. Chemical and product analysis shall be conducted on each lot of material as described in a referenced ASTM document and shall conform to the required chemical composition for carbon, silicon, manganese, phosphorus, sulfur, chromium, nickel, molybdenum, copper, and iron. The material shall also be subjected to tension test, flaring test, and hydrostatic or nondestructive test to determine its mechanical properties which shall be in conformity with the tensile strength, yield strength, and elongation requirements.
Chemical Composition (% as per ASTM B668)
| Element | Content (%) |
|---|---|
| Nickel (Ni) | 30.0 – 34.0 |
| Chromium (Cr) | 26.0 – 28.0 |
| Molybdenum (Mo) | 3.0 – 4.0 |
| Copper (Cu) | 0.6 – 1.4 |
| Iron (Fe) | Balance |
| Carbon (C) | ≤ 0.020 |
| Manganese (Mn) | ≤ 2.0 |
| Silicon (Si) | ≤ 1.0 |
| Sulfur (S) | ≤ 0.030 |
| Phosphorus (P) | ≤ 0.030 |
📌 Nickel + Molybdenum + Copper → high resistance to reducing media (sulfuric acid).
📌 Chromium + Molybdenum → strong resistance to oxidizing agents and pitting/crevice corrosion.
2. Mechanical Properties (Room Temperature, per ASTM B668)
| Property | Requirement |
|---|---|
| Tensile Strength (min) | 550 MPa (80 ksi) |
| Yield Strength, 0.2% offset (min) | 240 MPa (35 ksi) |
| Elongation (min) | 35 % |
3. Dimensions & Manufacturing
- Type: Seamless & Welded tubes
- OD Range: 6 mm – 219 mm (1/4” – 8”)
- Wall Thickness: 0.7 mm – 12.7 mm (SCH 5 to SCH 40 & heavier)
- Length: Straight lengths up to 12 m, U-bent tubes available
- Finish: Bright annealed (BA), solution annealed & pickled, polished
4. Heat Treatment
- Solution Annealed at approx. 1100 – 1150 °C (2010 – 2100 °F), followed by rapid cooling.
- Ensures corrosion resistance and mechanical strength.
5. Corrosion Resistance
- Excellent resistance to sulfuric acid, phosphoric acid, and organic acids.
- High resistance to chloride-induced pitting and crevice corrosion.
- Resistant to stress corrosion cracking in chloride-bearing environments.
- Often used as a cost-effective alternative to higher alloys (Alloy 625, C-276).
6. Applications
- Chemical & petrochemical processing (sulfuric acid, phosphoric acid plants)
- Oil & gas industry (tubing in sour service environments)
- Desalination plants & seawater handling systems
- Heat exchangers, condensers, evaporators
- Pollution control & flue gas cleaning systems
We offer high-quality N08028 seamless pipes, perfect for a wide range of industrial applications. Our seamless pipes are made from N08028 alloy, which is known for its excellent corrosion resistance and high strength, These seamless pipes are manufactured using advanced technology and strict quality control processes to ensure superior durability and performance. They are capable of withstanding extreme temperatures and harsh environments, making them ideal for use in chemical processing, petrochemical, and power generation industries, With a smooth and uniform surface finish, our N08028 seamless pipes are easy to install and require minimal maintenance, saving you time and money in the long run. With a wide range of sizes and specifications available
