Hyundai Welding S-7018.W E7018-W1 Weathering Steel Electrode

Overview

The Hyundai Welding S-7018.W is a low hydrogen stick electrode for weathering steel, classified to AWS A5.5 / ASME SFA-5.5 E7018-W1, JIS Z 3214 DA5026G and EN ISO 2560-A E42 2 B 3 2. Its weld metal contains copper, nickel and chromium so that the joint develops corrosion behaviour compatible with the weathering steel around it, rather than becoming a preferentially corroding seam.

Hyundai Welding describes the product as suitable for offshore and onshore construction, with high resistance to corrosion caused by seawater or combinations of oil, gas and seawater. Seven Star LLC supplies the Hyundai Welding S-7018.W from Muscat to customers in Oman and the GCC, and the manufacturer datasheet is attached to this page.

Welding Weathering Steel

As general background, weathering steels are low-alloy structural steels with small additions of copper, chromium and nickel. Exposed to the atmosphere they form a dense, adherent oxide layer that slows further corrosion, which is why they are used unpainted on bridges, towers and some industrial structures. A weld made with a plain carbon steel filler would lack these elements and could corrode faster than the base metal, especially in single-pass or exposed cap layers.

A W1 class electrode such as the Hyundai Welding S-7018.W solves this by alloying the deposit. The datasheet gives a typical 0.36 % Cu, 0.23 % Ni and 0.24 % Cr, so the cap and fill passes share the corrosion character of the plate. Being a basic low hydrogen product, it also gives the crack resistance expected from an E7018 type electrode.

Hyundai Welding S-7018.W Technical Profile

Typical chemistry is 0.06 % C, 0.54 % Si, 0.65 % Mn, 0.014 % P, 0.006 % S, 0.36 % Cu, 0.23 % Ni and 0.24 % Cr. Typical mechanical values are 505 MPa (73 ksi) yield, 573 MPa (83 ksi) tensile, 26 % elongation and 100 J (74 ft·lbs) at -20 °C (0 °F). The Hyundai Welding S-7018.W runs on AC or DC+ in positions 1G, 2F, 3G and 4G.

Diameters are 2.6 mm and 3.2 mm in 350 mm length, 4.0 mm and 5.0 mm in 400 mm, and 6.0 mm in 450 mm. The 6.0 mm size is listed for flat and horizontal-fillet only. Rods are packed in 5 kg (11 lbs) packets, standard or vacuum, and 20 kg (44 lbs) cartons. Redrying is at 300 to 350 °C for 0.5 to 1 hour. No approval marks are printed on this datasheet.

Key Features

Features of the Hyundai Welding S-7018.W listed by the manufacturer include:

• Suitable for both offshore and onshore construction.
• High resistance to corrosion caused by seawater or by combinations of oil, gas and seawater.
• Copper, nickel and chromium in the all-weld metal.
• AWS A5.5 E7018-W1 classification for weathering steel.
• Typical toughness of 100 J at -20 °C.
• AC or DC+ polarity with all common plate positions.
• Diameters from 2.6 mm up to 6.0 mm.
• Low hydrogen basic coating with a 300 to 350 °C redrying requirement.

Applications in a Coastal Climate

The application area given on the datasheet is high tensile weathering steel. Around the Gulf of Oman and the Arabian Sea this covers steel structures exposed to salt-laden air, such as jetty and berth steelwork, structures at desalination intakes, marine terminals near Sohar and Duqm, and onshore facilities within reach of sea spray. The Hyundai Welding S-7018.W is selected where the designer has specified weathering steel and the weld must keep the same corrosion behaviour.

Seven Star LLC also supplies welding machines such as the ESAB Rebel EMP 285ic and the Lincoln Electric Power Wave S500, and submerged arc consumables such as the LongTeng EL8 SAW wire for heavy shop seams. Explore other stick electrodes in the welding electrodes category.

Selecting the Right Filler for Weathering Steel Joints

As general guidance, designers choose between three options for weathering steel joints: a matching alloyed filler such as the Hyundai Welding S-7018.W for every pass, a matching filler only for the exposed surface layers with carbon steel underneath, or carbon steel filler throughout where the joint will be painted or hidden. The choice depends on plate thickness, number of passes and whether the structure will be left unpainted. Multi-pass welds pick up some alloy from the base metal, while single-pass fillet welds rely almost entirely on the electrode chemistry.

Inspection is the same as for any low hydrogen structural weld: visual examination, then magnetic particle or ultrasonic testing as the specification demands. For exposed weathering steel the visual quality of the cap also matters, since spatter and undercut become visible as the protective oxide develops. The Hyundai Welding S-7018.W current ranges, from 60 A on 2.6 mm up to 300 A on 6.0 mm, give welders room to set a smooth, controlled arc for a clean finish.

Technical Specifications

Typical values below come from the Hyundai Welding S-7018.W datasheet.

Welding Parameters

Good Practice

General guidance for weathering steel is that every pass exposed to the atmosphere, especially the cap, should be made with a matching alloyed filler, while some procedures allow carbon steel filler for hidden inner passes in multi-pass joints. Follow the structural design specification. As with all basic electrodes, keep the Hyundai Welding S-7018.W dry, redry at 300 to 350 °C when required and use holding ovens on site.

In storage yards close to the sea, keep cartons off the ground and under cover, and return unused electrodes to a holding oven at the end of each shift rather than leaving them in open packets overnight, when humidity is highest.

Datasheet

The official Hyundai Welding S-7018.W datasheet is available for download from this page.

Call To Action

For pricing and availability of the Hyundai Welding S-7018.W, send Seven Star LLC your diameters, quantities and documentation requirements. We serve marine, structural and industrial customers across Oman and the GCC from Muscat with engineering support.