Hyundai S-2594.16 E2594-16 Super Duplex Stainless Electrode

The Hyundai S-2594.16 is a covered stick electrode for shielded metal arc welding (SMAW) of super duplex stainless steels such as UNS S32750 and UNS S32760. It is classified to AWS A5.4 / ASME SFA-5.4 E2594-16 and EN ISO 3581-A E 25 9 4 N L, and its all-weld metal reaches a PREN of 41 according to the Hyundai Welding datasheet. With a service temperature of up to 250 °C, high resistance to pitting corrosion and embrittlement, and easy slag removal with a good bead appearance, it targets the seawater, offshore and desalination work that is common across Oman. Seven Star LLC supplies the Hyundai S-2594.16 and provides the official datasheet on this page.

What the Hyundai S-2594.16 Is Designed For

Super duplex stainless steel combines roughly equal amounts of ferrite and austenite with high chromium, molybdenum and nitrogen. The result is a material with about twice the yield strength of standard austenitic grades and outstanding resistance to chloride pitting and crevice corrosion. Firewater ring mains, seawater cooling systems, reverse osmosis high-pressure piping, subsea manifolds and offshore topside process lines are typical places where S32750 and S32760 are specified.

To keep those properties across a welded joint, the filler must deposit a weld metal that is at least as corrosion resistant as the base material. The Hyundai S-2594.16 does this with a typical deposit of 25.2% chromium, 9.5% nickel, 3.8% molybdenum and 0.23% nitrogen. The “-16” suffix indicates a rutile-type covering usable on AC or DC electrode positive, which gives a smooth, stable arc for manual welding in the shop or on site.

Key Features from the Datasheet

• AWS A5.4 E2594-16 super duplex stick electrode.
• PREN 41 in the all-weld metal.
• Service temperature up to 250 °C.
• High resistance to pitting corrosion and embrittlement.
• Easy to remove slag and good bead appearance.
• Polarity: AC or DC+.
• Welding positions listed: 1G (flat) and 2F (horizontal fillet).
• Redrying: 350 °C (662 °F) for 1 hour.

Typical All-Weld Metal Chemistry

Values are in weight percent and are typical, as published by Hyundai Welding. The low carbon level of 0.02% supports resistance to intergranular corrosion, while nitrogen stabilises the austenite phase and boosts pitting resistance.

Typical Mechanical Properties

Sizes and Recommended Current

Packaging is a 2.5 kg (5.5 lbs) PVC packet, packed four to a 10 kg (22 lbs) carton. Although the datasheet marks 1G and 2F as welding positions, it also prints vertical-up and overhead current ranges for most sizes; confirm positional use in your procedure qualification.

Applications in Oman and the GCC

Oman’s desalination plants, coastal power stations, LNG facilities and offshore assets all use super duplex piping in seawater and chloride-rich service. The Hyundai S-2594.16 is a candidate consumable for:

• Seawater intake, brine and high-pressure reverse osmosis piping in desalination plants.
• Firewater and deluge systems on offshore platforms and onshore terminals.
• Process piping, separators and heat exchanger components in oil and gas service.
• Repair welding of super duplex pumps, valves and fittings during maintenance shutdowns.
• Tie-ins and site welds where GTAW or orbital equipment is impractical.

General Notes on Welding Super Duplex

The following is general welding knowledge, not part of the Hyundai datasheet. Super duplex is sensitive to heat input and interpass temperature: too little heat can leave excessive ferrite, while too much, or a high interpass temperature, risks forming intermetallic phases such as sigma that reduce toughness and corrosion resistance. Project specifications such as NORSOK M-601 or client standards usually set limits on heat input, interpass temperature, ferrite content and corrosion testing (for example ASTM G48). Electrodes should be kept dry, redried as the manufacturer states (350 °C for 1 hour for the Hyundai S-2594.16) and held in a heated quiver on site. Clean, grind-free joint preparation and proper root shielding on the back side of the weld are also important for corrosion performance.

Base Materials and Joint Types

The datasheet names UNS S32750 and UNS S32760 as the application base materials for the Hyundai S-2594.16. As general practice, over-alloyed super duplex fillers of this type are also used by many fabricators on standard 22Cr duplex where higher weld metal corrosion resistance is required, but that choice should be confirmed by the project engineer and the qualified procedure. Typical joints include butt welds in pipe and fittings, socket and branch connections, and fillet welds on supports and structural attachments. For root passes in pipe, many procedures combine a GTAW root with the Hyundai S-2594.16 for fill and cap, balancing root quality with manual productivity. Each combination should be backed by procedure qualification, ferrite measurement and any corrosion testing the specification calls for, so the Hyundai S-2594.16 deposit is proven on the actual base material and thickness used.

Why Use the Hyundai S-2594.16

The combination of a PREN 41 deposit, 927 MPa typical tensile strength and a rutile covering that welds on either AC or DC+ makes the Hyundai S-2594.16 a versatile choice for super duplex fabrication and repair. AC capability can help where only basic transformer machines are available on site, while the five diameters from 2.0 to 5.0 mm cover root, fill and cap passes on a wide range of wall thicknesses.

Related Products on Our Site

Other welding products from Seven Star LLC include the Lincoln Electric SuperArc L-59 ER70S-6 Solid MIG Welding Wire, the LongTeng EL8 Carbon Steel Submerged Arc Welding Wire and the Lincoln Electric Power Wave S500. See all stick electrodes in our Welding Electrodes category.

Request a Quotation

To order the Hyundai S-2594.16, send Seven Star LLC the diameters and quantities you need, along with any project specification, certificate or testing requirements. Our Muscat team will confirm the details, share the manufacturer datasheet attached here, and coordinate delivery to your workshop, plant or offshore supply base in Oman and the wider GCC.