Types of Welding Electrodes Explained — A Buyer's Guide for NE India

Written by the counter team at Multi Trade Combines — 33 years supplying NE workshops.

We are an authorised ESAB dealer on AT Road, Guwahati — one of the leading welding consumables suppliers in Northeast India. This guide is based on what our customers actually ask when building their electrode stock for the first time, or troubleshooting weld quality issues in the field.

Electrode Classification at a Glance

E6013 — The Everyday Workshop Electrode

E6013 (AWS) / IS 815 equivalent is the general-purpose mild steel electrode found in every welding workshop across NE India. The ESAB OK 46.00 is the benchmark E6013-class electrode — here is why it is the default starting choice:

• Easy arc striking and re-striking: the rutile (titanium dioxide) coating produces an easy, stable arc that restarts reliably even in the field. Less experienced welders can produce acceptable beads quickly.
• Smooth, flat bead profile: the slag detaches cleanly, the bead is smooth and the appearance is good — important for visible structural joints and fabricated components where aesthetics matter alongside strength.
• All-position welding: the "1" in the classification means flat, horizontal, vertical and overhead — critical for site welders who weld in every conceivable position on structural frames.
• Works on AC: most small workshops and site generators run AC-output welding transformers. E6013 works on AC current without modification. E7018, by contrast, prefers DC+ and may be erratic on small AC machines.
• Forgiving of moderately dirty or oxidised surfaces: not ideal for heavily rusty or contaminated steel, but handles mill scale and light surface oxidation better than low-hydrogen electrodes.

E7018 — For Structural, Code and Thick-Section Work

E7018 is the structural welding electrode — the one your welding inspector or PWD project specification will often call out by name. Key applications in NE India's construction and infrastructure sector:

• Bridge and structural steel fabrication: NE India has seen extensive bridge construction on national highway projects across the Brahmaputra river and its tributaries. AWS D1.1 and IS 9595 structural steel welding requirements specify low-hydrogen electrodes — E7018 meets this requirement.
• Thick section welding (above 12 mm): thick sections accumulate hydrogen in the weld zone if a high-hydrogen electrode is used, causing delayed cracking (also called cold cracking or hydrogen cracking). E7018 with a baked electrode (oven dried at 300–350°C for 1–2 hours before use) eliminates this risk.
• Pressure vessels and piping: even in Assam's oil and gas industry, where pressure-containing welds require certified procedures and low-hydrogen filler metals. ESAB OK 48.00 and similar E7018 grades are specified in most relevant welding procedure specifications (WPS).
• Storage is critical: E7018 must be stored in a sealed, moisture-proof container and ideally in an electrode oven (50–80°C holding temperature). NE India's monsoon humidity can raise moisture content to damaging levels within hours of opening a box. We stock electrode ovens at our Guwahati counter — non-negotiable equipment if you are buying E7018 in quantity.

Stainless Steel Electrodes — E308L and E309L

For fabrication involving 304 or 316 stainless steel — food processing equipment, pharmaceutical vessels, dairy equipment, chemical piping — the correct electrode family is the austenitic stainless grades:

• E308L-16: for welding 304 stainless to 304 stainless. The "L" indicates low carbon content — essential to prevent carbide precipitation (sensitisation) in the heat-affected zone, which causes intergranular corrosion. ESAB OK 61.30 is the standard choice.
• E316L-16: for 316 stainless — the molybdenum-bearing grade with enhanced chloride corrosion resistance. Required for coastal or chemical environments and food processing where the slightly higher chloride resistance of 316 is specified.
• E309L-16: for joining stainless steel to mild steel — dissimilar metal joints. Common when stainless clad plates are welded to mild steel structures, or when stainless components are attached to mild steel frames. The buffer composition handles the differing metallurgies.
• Stainless welding tips: use DC+ current only for best results with stainless electrodes. Use a stainless steel wire brush (not a mild steel brush) to clean weld zones — mild steel contamination causes rust staining and can compromise corrosion resistance. Back-purge with argon gas for pipe welds when root corrosion resistance is critical.

MIG Wire — When Wire-Feed is the Better Choice

MIG welding wire (GMAW solid wire, ER70S-6) is the consumable for high-deposition rate production welding in a workshop setting:

• Higher deposition rate: continuous wire feed deposits weld metal faster than individual stick electrodes — a significant productivity advantage for high-volume fabrication. A MIG welder at 200A deposits roughly 4–5 kg of weld metal per hour; a skilled MMA welder at the same amperage deposits 1.5–2 kg/hour.
• Cleaner welds: GMAW leaves no slag, produces minimal spatter (with correct parameters) and gives a smooth bead that requires less inter-pass cleaning in multi-pass work.
• Less suited for site use: MIG requires a shielding gas supply and a wire-feed machine. Gas (CO2 or Ar/CO2 mix) gets blown away by wind above a light breeze — outdoor MIG welding on NE India's exposed construction sites is impractical without a windshield. Stick (MMA) welding is far more wind-tolerant on exposed sites.
• ER70S-6 grade: the standard mild steel MIG wire, with higher manganese and silicon content than ER70S-3 — providing better tolerance of mill scale and lightly oxidised surfaces and better deoxidation in the weld pool. This is the wire we stock at our counter.

Electrode Storage in NE India — The Monsoon Threat

Moisture in welding electrodes is the most common cause of weld quality problems in NE India's 5–6 month monsoon season. Here is how to manage electrode storage correctly:

• E6013 and general rutile electrodes: store in original sealed containers in a dry room. If opened, use within a week in humid conditions or re-dry at 150°C for 1 hour.
• E7018 and low-hydrogen grades: once opened, electrodes must be used within 4 hours in a humid environment or stored in a holding oven at 70–80°C. Do not leave open canisters overnight during monsoon — a full box can absorb enough moisture in one humid NE India night to compromise every electrode in it.
• Stainless steel electrodes: store in sealed packaging; re-dry at 200–250°C if exposed to humidity for more than a few hours. Moisture in stainless electrodes causes porosity and embrittlement in the weld deposit.
• MIG wire spools: seal with the plastic bag and wire-end clip every time you stop welding. A half-used spool left open in a humid workshop will surface-oxidise within a day — the rust particles contaminate the weld pool and cause porosity.

Related Products

• ESAB Welding Electrode
• MIG Welding Wire
• Welding Machines Catalogue
• ESAB Brand Page

Frequently Asked Questions