Delivery Time:10 DAYS
Certification:ISO9001:2008
SS 1.4462 Welded Steel Tube ASTM A928 UNS S31803 Super Duplex Stainless Steel Pipe
Description:
Duplex & Super Duplex Welded Stainless Steel Pipe appeared in the marketplace due to the need to combat the shortcomings of austenitic and ferritic steels. It was found that a mixture of these two materials resulted in higher strength, reduced weight, good weldability and increased resistance to stress corrosion cracking.
Unlike similar steels, duplex also displays an improved resistance to localised corrosion, particularly pitting, crevice corrosion and stress corrosion cracking. Due to its ferritic qualities, duplex steel also shows very good resistance to stress corrosion cracking when compared to standard austenitics. In some cases, the strength of duplex steel can be up to double that of the most commonly used grades of stainless steel.
Another benefit of duplex steels is that because it has a lower nickel and molybdenum content than other austenitic stainless steels, it can prove to be a more cost effective option due to its lower alloy content.
These benefits clearly show why Duplex steels have become popular in applications such as pressure vessels, cooling pipes and storage tanks.
Duplex becomes brittle at extreme temperatures so its use is normally restricted to a maximum temperature of 300 degrees. Duplex also shows signs of embrittlement at –50 degrees.
Advantages:
1. Stronger than 300 series stainless steel which also brings weight advantages
2. High resistance to pitting, crevice corrosion and stress corrosion cracking
3. Higher heat conductivity and lower thermal expansion than austenitic steels
Applications:
1. Pipes for production and transportation of oil and gas
2. Structural and mechanical components
3. Heat exchangers
4. Cooling pipes
Specifications:
| Specifications (ASTM/ASME) Duplex Stainless Steel Pipe | ||||
| Alloy | UNS Designation | Material Specification |
Tubing Specification |
Pipe Specification |
| 2205 | S31803/S32205 | A 240/SA-240 | A 270 | A 790/SA-790 |
| A 789/SA-789 | A928/SA928 | |||
| Specifications (ASTM/ASME) Super Duplex Stainless Steel Pipe | ||||||
| Alloy | UNS Designation | Minimum Tensile Strength | Minimum Yield Strength 0.2% Offset |
Minimum Percent (%) Elongation in 2 inches (50.8 mm) |
||
| (psi) | (MPa) | (psi) | (MPa) | |||
| 2507 | S32750 | 116,000 | 800 | 80,000 | 550 | 15 |
Chemical Compositions:
| Chemical Composition (%) Duplex Stainless Steel Pipe | ||
| Alloy | 2205 | 2205 |
| UNS Designation | S31803 | S32205 |
| Carbon (C) max. | 0.030 | 0.030 |
| Manganese (Mn) max. | 2.00 | 2.00 |
| Phosphorus (P) max. | 0.030 | 0.030 |
| Sulfur (S) max. | 0.020 | 0.020 |
| Silicon (Si) max. | 1.00 | 1.00 |
| Chromium (Cr) | 21.0 - 23.0 | 22.0 - 23.0 |
| Nickel (Ni) | 4.5 - 6.5 | 4.5 - 6.5 |
| Molybdenum (Mo) | 2.5 - 3.5 | 3.0 - 3.5 |
| Nitrogen (N) | 0.08 - 0.20 | 0.14 - 0.20 |
| Iron (Fe) | Balance | Balance |
