Super Duplex Tube Fittings Manufacturer
2507 (S32750) and 32760 (S32760).
For seawater, offshore, and sour gas applications.
- PREN > 40, exceptional resistance to pitting and crevice corrosion
- Yield strength 550-640 MPa, 2.5x stronger than 316 stainless steel
- Same 1-1/4 turn installation as standard fittings, no retraining needed
Why Choose NPTLOK Super Duplex Tube Fittings？
NPTLOK manufactures super duplex tube fittings in grades 2507 (UNS S32750) and 32760 (UNS S32760), suitable for instrumentation systems operating in seawater, offshore, chemical processing, and sulfur-containing gas environments.
We offer reliable double-ferrule fittings with full material traceability, flexible manufacturing capabilities, and consistent supply to help you build safe and reliable piping systems.
Connect two Super Duplex tubes end to end.Most common fitting for Super Duplex systems.
Sizes 1/8“ to 1”.
Connect Super Duplex tube to male thread. NPT, BSP, or metric.
For connecting to threaded ports.
Connect Super Duplex tube to female thread.
Same thread options.
90° bend,both ends connect to the Super Duplex tube.
For tight spaces where a straight union will not fit.
90° bend, Super Duplex tube to male thread.
Change direction and connect to a threaded port.
90° bend, Super Duplex tube to female thread.
Same thread options.
Why NPTLOK Super Duplex Tube Fittings？
Suitable for H₂S-containing environments.
Prevents galling and seizing. Smooth tightening and loosening
Also guaranteed to fit with 1-1/4 turns as normal using standard tools.
MTC 3.1 certificate with every batch.
Double Ferrule Design Ensures Reliable Sealing
NPTLOK Super Duplex Tube Fittings feature a mature double ferrule sealing structure, in which the front and rear ferrules work in concert to create a stable mechanical grip and seal on the surface of the tubing. This design effectively reduces the impact of vibration, pressure, and temperature on connection reliability, ensures long-term, leak-free operation of instrumentation piping systems, and makes it suitable for applications such as oil and gas, offshore platforms, and chemical processing.
Same Installation as 316, No Process Change
Super Duplex tube fittings use the same gaugeability and 1-1/4 turn installation rule as standard 316 stainless steel fittings.No new tools. No new training. No change in installation procedures. Field crews can install them the same way they always have.
Full Traceability for Project Compliance
Material traceability is a critical requirement for ensuring the safe operation of equipment and compliance with project specifications. Every batch of NPTLOK super duplex stainless steel tube fittings can be traced back to the raw material furnace number, and provides Material Test Certificate (MTC), containing data on chemical composition and mechanical properties. Complete quality records help you complete project acceptance, quality audits, and long-term maintenance management.
Your Reliable Super Duplex Tube Fittings Supplier
We manufacture Super Duplex tube fittings in 2507 (S32750) and 32760 (S32760). Full range of types. Sizes from 1/8“ to 1”. Full traceability. MTC with every batch.
What you get:
Applications of Super Duplex Fittings
Used in instrumentation tubing systems handling acids, alkalis, and chloride-containing chemicals. Super duplex offers stability in environments with high chlorides and high pressure.
For seawater desalination, reverse osmosis, and industrial water treatment systems. Performs reliably in high-salinity and chloride-rich environments.
For platforms, subsea equipment, and marine vessels. Super Duplex provides reliable corrosion resistance in seawater and other high-chloride environments.
Used in oil and gas extraction, natural gas processing, and refining and petrochemical facilities.Super duplex tube fittings provide reliable leak-tight connections under high-pressure conditions and in environments containing H₂S, CO₂, and other corrosive media.
Both are high-alloy super duplex grades. Due to the addition of copper and tungsten, S32760 (32760) exhibits better corrosion resistance than S32750(2507) in certain highly corrosive environments.
| Dimension | Edelstahl 316 | Super Duplex (2507) |
| Yield strength | ~220 MPa | ~550-640 MPa |
| Tensile strength | ~485 MPa | ~795 MPa |
| PREN value | ~25 | > 40 |
| Cost | Lower | Higher (but less than 2x) |
| Magnetic | Non-magnetic | Slightly magnetic |
The PREN value of 2205 is approximately 35, while that of Super Duplex is greater than 40. The higher PREN value gives Super Duplex superior resistance to pitting and crevice corrosion. Besides, Super Duplex has higher strength and corrosion resistance, making it suitable for more severe environments, such as seawater, offshore platforms, sulfur-containing gases, and high-chloride environments.
PREN (Pitting Resistance Equivalent Number) measures resistance to pitting corrosion. Super Duplex has PREN > 40, compared to 316 at ~25. Higher PREN means better resistance to pitting and crevice corrosion in chloride environments like seawater.
Yes. Our Super Duplex Tube Fittings have the very same dimensions as 316 fittings, and therefore fit into the very same tube stock as well as using the very same thread standards. That means that you can easily replace the failing 316 fittings with matching Super Duplex fittings without having to retrain to install them.
