Inconel 625 tube fittings are compression fittings machined from Alloy 625 (UNS N06625) bar for instrument, control and injection tubing in the harshest environments: subsea control systems, sour gas wells and processing plants, hot seawater and acid service. Alloy 625 tubing and fittings resist the chloride pitting, crevice corrosion and stress corrosion cracking that limit 316 and duplex, and keep high strength over a wide temperature range.
Raaj Fittings makes Alloy 625 double ferrule and single ferrule fittings, with unions, connectors, elbows, tees, bulkheads and adapters, at our two plants in India, in metric and imperial tube sizes, for instrumentation and subsea contractors in the Middle East, Europe and the Americas.
| Material | Alloy 625, UNS N06625 (bar to ASTM B446) |
|---|---|
| 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, reducers 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; EN 10204 3.2 on request |
| Element, % | UNS N06625 |
|---|---|
| Nickel (Ni) | 58.0 min |
| Chromium (Cr) | 20.0 – 23.0 |
| Molybdenum (Mo) | 8.0 – 10.0 |
| Niobium + tantalum (Nb + Ta) | 3.15 – 4.15 |
| Iron (Fe) | 5.0 max |
| Carbon (C) | 0.10 max |
| Manganese (Mn) | 0.50 max |
| Silicon (Si) | 0.50 max |
| Phosphorus (P) | 0.015 max |
| Sulphur (S) | 0.015 max |
| Aluminium (Al) | 0.40 max |
| Titanium (Ti) | 0.40 max |
| Cobalt (Co) | 1.0 max |
| Grade | UNS | Werkstoff Nr. | EN / DIN designation | Common names |
|---|---|---|---|---|
| Alloy 625 | N06625 | 2.4856 | NiCr22Mo9Nb | Inconel® 625 |
For less severe offshore service, duplex 2205, super duplex 2507 or Monel 400 tube fittings may be more economical.
Alloy 625 bar 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.
Mainly in subsea control systems, sour gas instrumentation, chemical injection lines and hot seawater or acid service, where 316 and duplex tube fittings would corrode.
No. Fittings and tubing should be the same alloy so the ferrules grip correctly and no part of the joint becomes the weak point for corrosion.
Yes, in imperial sizes from ⅛" to 1" OD and metric sizes from 3 to 25 mm OD, with NPT, BSPT or BSPP threaded ends.
Yes. Alloy 625 is widely used for sour service and can be supplied to NACE MR0175 / ISO 15156 when specified.