Super Duplex 2507 Tube Fittings are made to Super duplex 2507, UNS S32750 for seawater and offshore service. Double and single ferrule compression fittings connect Super Duplex 2507 instrument and control tubing.
Raaj Fittings machines Super Duplex 2507 tube fittings in-house at our two plants in India, in metric and imperial tube sizes, and exports them to EPC contractors, fabricators and stockists across the Middle East, Europe and the Americas, with full traceability and EN 10204 certificates.
| Material specification | Super duplex 2507, UNS S32750 |
|---|---|
| Tube OD | Metric 3 to 25 mm; imperial ⅛" to 1" |
| Fitting types | Double ferrule and single ferrule compression fittings; unions, connectors, elbows, tees, bulkheads and adapters |
| End connections | Compression tube ends; NPT (ASME B1.20.1), BSPT and BSPP (BS 21 / ISO 7-1) threads |
| Certification | EN 10204 3.1 mill test certificate as standard; EN 10204 3.2 on request |
Super duplex 2507 (UNS S32750) contains about 25% chromium, 7% nickel, 4% molybdenum and 0.3% nitrogen, giving a pitting resistance equivalent number (PREN) of at least 40. It handles warm seawater and high-chloride brines that are beyond duplex 2205, with a minimum yield strength above 550 MPa.
| Element, % | S32750 |
|---|---|
| Carbon (C) | 0.030 max |
| Manganese (Mn) | 1.20 max |
| Phosphorus (P) | 0.035 max |
| Sulphur (S) | 0.020 max |
| Silicon (Si) | 0.80 max |
| Chromium (Cr) | 24.0 – 26.0 |
| Nickel (Ni) | 6.0 – 8.0 |
| Molybdenum (Mo) | 3.0 – 5.0 |
| Nitrogen (N) | 0.24 – 0.32 |
| Copper (Cu) | 0.50 max |
| Property | Super Duplex 2507 |
|---|---|
| Tensile strength, min. | 800 MPa (116 ksi) |
| Yield strength (0.2%), min. | 550 MPa (80 ksi) |
| Elongation, min. | 15% |
| Hardness, max. | 310 HBW |
| UNS | Werkstoff Nr. | EN / DIN | Other |
|---|---|---|---|
| S32750 | 1.4410 | X2CrNiMoN25-7-4 | ASTM A182 F53 |
Super duplex tube fittings are used with super duplex instrument tubing where even duplex 2205 is marginal, such as hot, salt-laden offshore atmospheres and subsea controls. Fittings and tubing must be the same material.
Bar stock is PMI-verified and traceable by heat number; bodies, nuts and ferrules are dimensionally inspected and threads gauge-checked. Every order is supplied with EN 10204 3.1 certificates, with EN 10204 3.2 certification and third-party inspection by the buyer's nominated agency on request.
2507 has more chromium, molybdenum and nitrogen, giving a PREN of at least 40 against about 35 for 2205, and a higher yield strength. It is chosen for warmer seawater and higher chloride levels.
Ferrite content (often 35–65%), Charpy impact tests at low temperature, ASTM A923 for intermetallic phases and ASTM G48 pitting tests are typical, together with hardness checks.
They should be used with Super Duplex 2507 tubing. Matching the materials ensures the ferrules grip correctly and that no part of the joint becomes the weak point for corrosion.
Every order is supplied with EN 10204 3.1 mill test certificates showing heat chemistry and mechanical properties to Super duplex 2507, UNS S32750. EN 10204 3.2 certification and inspection by your nominated third-party agency are available on request.