{"product_id":"lincoln-innershield-ns-3m-fcaw-s-welding-wire","title":"Lincoln E70T-4 (Innershield NS-3M FCAW-S Welding Wire)","description":"\u003c!-- Wire Lane E | lincoln-innershield-ns-3m-fcaw-s-welding-wire | 2026-06-16 --\u003e\n\u003ch2\u003eLincoln Innershield NS-3M — Ultra-High Deposition Self-Shielded FCAW Wire\u003c\/h2\u003e\n\u003cp\u003eLincoln Electric Innershield® NS-3M is a self-shielded, flux-cored arc welding wire engineered for the \u003cstrong\u003ehighest available deposition rates\u003c\/strong\u003e among all Innershield electrodes. Classified per \u003cstrong\u003eAWS A5.20 \/ A5.36: E70T-4 \/ E70T4-AZ-CS3\u003c\/strong\u003e, NS-3M is designed specifically for single or multiple-pass welding on carbon steel in applications without impact strength requirements. Its E70T-4 chemistry delivers melt-off rates up to 14.8 lb\/hr at 240 in\/min on 5\/64 in diameter, making it the productivity leader for high-speed flat and horizontal production welding. NS-3M also provides exceptional resistance to hydrogen cracking and porosity on steel containing sulfur or other surface contaminants — a significant advantage when welding structural steel that has not been ideally prepared.\u003c\/p\u003e\n\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n\u003cth\u003eParameter\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eAWS Classification\u003c\/td\u003e\n\u003ctd\u003eE70T-4 \/ E70T4-AZ-CS3 (AWS A5.20 \/ A5.36)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eCWB Classification\u003c\/td\u003e\n\u003ctd\u003eCSA W48 E490T4-AZ-CS3-H16\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eISO Classification\u003c\/td\u003e\n\u003ctd\u003eISO 17632-A: T 38 Z V N 3\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eAvailable Diameters\u003c\/td\u003e\n\u003ctd\u003e5\/64 in (2.0 mm), 0.120 in (3.0 mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eShielding Gas\u003c\/td\u003e\n\u003ctd\u003eNone — self-shielded (FCAW-S)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePolarity\u003c\/td\u003e\n\u003ctd\u003eDCEP (DC electrode positive)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eWelding Position\u003c\/td\u003e\n\u003ctd\u003eFlat (1G \/ 1F) and Horizontal (2G \/ 2F)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eTensile Strength (required AWS E70T-4)\u003c\/td\u003e\n\u003ctd\u003e480–660 MPa (70–95 ksi)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eYield Strength (typical)\u003c\/td\u003e\n\u003ctd\u003e410 MPa (59 ksi) as-welded\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eTensile Strength (typical)\u003c\/td\u003e\n\u003ctd\u003e570–640 MPa (82–93 ksi) as-welded\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eElongation (typical)\u003c\/td\u003e\n\u003ctd\u003e23 % in 2 in\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eElectrode Stick-Out (CTWD)\u003c\/td\u003e\n\u003ctd\u003e54 mm (2-1\/4 in) typical\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDeposition Rate (5\/64 at 200 in\/min)\u003c\/td\u003e\n\u003ctd\u003e4.6 kg\/hr (10.1 lb\/hr)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDeposition Rate (5\/64 at 240 in\/min)\u003c\/td\u003e\n\u003ctd\u003e5.5 kg\/hr (12.1 lb\/hr)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eApplications and Industries\u003c\/h2\u003e\n\u003cp\u003eNS-3M's E70T-4 rating per \u003ca href=\"https:\/\/www.aws.org\/standards\/detail\/AWS-A5-20-2005\" rel=\"nofollow\"\u003eAWS A5.20\u003c\/a\u003e designates a self-shielded electrode with no specified impact toughness requirements, intended for maximum deposition productivity. Its unique tolerance for sulfur-contaminated steel makes it especially valuable in:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSteel service center processing lines\u003c\/strong\u003e — automated welding of hot-rolled structural shapes where mill scale and sulfur content vary\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHigh-production fabrication shops\u003c\/strong\u003e — continuous fillet welds on beams, girders, and built-up sections where throughput is the primary driver\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eConstruction site welding\u003c\/strong\u003e — no gas cylinder logistics; tolerates field conditions including light contamination on joint surfaces\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShipbuilding and barge fabrication\u003c\/strong\u003e — flat and horizontal fillet welds on large structural panels in open environments\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRailroad car and heavy transport manufacturing\u003c\/strong\u003e — floor pans, cross-members, and bracket attachments on thick-section carbon steel\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eProcess Technology and Selection Guide\u003c\/h2\u003e\n\u003cp\u003eNS-3M uses DCEP polarity — unlike NR-311 which uses DCEN — and achieves its extraordinary deposition rates through a highly efficient open-arc flux system. The aluminum-bearing flux chemistry (typical Al content 1.3–1.5 %) provides robust deaeration of the weld pool, preventing the porosity and cracking that would occur when welding steel containing elevated sulfur (S \u0026gt; 0.05 %) or other contaminants. This makes NS-3M the preferred choice in applications where steel quality or surface preparation is variable.\u003c\/p\u003e\n\u003cp\u003eAt 5\/64 in diameter with a 2-1\/4 in CTWD, NS-3M supports wire feed speeds from 200 to 240 in\/min at 280–315 amps. These currents produce deposition rates of 10–12 lb\/hr at 82–83 % efficiency — matching or exceeding many gas-shielded FCAW-G wires while requiring no shielding gas infrastructure. Per \u003ca href=\"https:\/\/www.lincolnelectric.com\/en-us\/products\/consumables\/Pages\/innershield-ns-3m.aspx\" rel=\"nofollow\"\u003eLincoln Electric product data\u003c\/a\u003e, NS-3M is recommended for single or multiple-pass welding on carbon and some low-alloy steels in applications without impact strength requirements.\u003c\/p\u003e\n\n\u003ch2\u003ePolarity and Parameter Table\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n\u003cth\u003eDiameter\u003c\/th\u003e\n\u003cth\u003ePolarity\u003c\/th\u003e\n\u003cth\u003eCTWD\u003c\/th\u003e\n\u003cth\u003eWFS (in\/min)\u003c\/th\u003e\n\u003cth\u003eVoltage (V)\u003c\/th\u003e\n\u003cth\u003eCurrent (A)\u003c\/th\u003e\n\u003cth\u003eDeposition (lb\/hr)\u003c\/th\u003e\n\u003cth\u003eEfficiency (%)\u003c\/th\u003e\n\u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e5\/64 in (2.0 mm)\u003c\/td\u003e\n\u003ctd\u003eDCEP\u003c\/td\u003e\n\u003ctd\u003e2-1\/4 in (54 mm)\u003c\/td\u003e\n\u003ctd\u003e200\u003c\/td\u003e\n\u003ctd\u003e29–31\u003c\/td\u003e\n\u003ctd\u003e280\u003c\/td\u003e\n\u003ctd\u003e10.1\u003c\/td\u003e\n\u003ctd\u003e83\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e5\/64 in (2.0 mm)\u003c\/td\u003e\n\u003ctd\u003eDCEP\u003c\/td\u003e\n\u003ctd\u003e2-1\/4 in (54 mm)\u003c\/td\u003e\n\u003ctd\u003e240\u003c\/td\u003e\n\u003ctd\u003e30–32\u003c\/td\u003e\n\u003ctd\u003e315\u003c\/td\u003e\n\u003ctd\u003e12.1\u003c\/td\u003e\n\u003ctd\u003e82\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cdiv itemscope itemtype=\"https:\/\/schema.org\/FAQPage\"\u003e\n  \u003cdiv itemscope itemprop=\"mainEntity\" itemtype=\"https:\/\/schema.org\/Question\"\u003e\n    \u003ch3 itemprop=\"name\"\u003eWhat AWS classification is Lincoln Innershield NS-3M?\u003c\/h3\u003e\n    \u003cdiv itemscope itemprop=\"acceptedAnswer\" itemtype=\"https:\/\/schema.org\/Answer\"\u003e\n      \u003cp itemprop=\"text\"\u003eNS-3M is classified as \u003cstrong\u003eE70T-4 per AWS A5.20\u003c\/strong\u003e and \u003cstrong\u003eE70T4-AZ-CS3 per AWS A5.36\u003c\/strong\u003e. The T-4 designation is a self-shielded electrode engineered for maximum deposition in flat and horizontal positions, with no specified Charpy V-Notch impact toughness requirement.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \u003cdiv itemscope itemprop=\"mainEntity\" itemtype=\"https:\/\/schema.org\/Question\"\u003e\n    \u003ch3 itemprop=\"name\"\u003eWhat polarity does NS-3M use — DCEP or DCEN?\u003c\/h3\u003e\n    \u003cdiv itemscope itemprop=\"acceptedAnswer\" itemtype=\"https:\/\/schema.org\/Answer\"\u003e\n      \u003cp itemprop=\"text\"\u003eNS-3M uses \u003cstrong\u003eDCEP (DC Electrode Positive)\u003c\/strong\u003e — also called reverse polarity. This is notably different from NR-311 (which uses DCEN). Connect the gun lead to the positive terminal and work clamp to the negative terminal. Verify polarity before running any Innershield electrode, as incorrect polarity causes an unstable arc and defective welds.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \u003cdiv itemscope itemprop=\"mainEntity\" itemtype=\"https:\/\/schema.org\/Question\"\u003e\n    \u003ch3 itemprop=\"name\"\u003eHow is NS-3M different from NR-311?\u003c\/h3\u003e\n    \u003cdiv itemscope itemprop=\"acceptedAnswer\" itemtype=\"https:\/\/schema.org\/Answer\"\u003e\n      \u003cp itemprop=\"text\"\u003eBoth are high-deposition, flat\/horizontal, self-shielded FCAW-S wires, but they differ in polarity and chemistry. \u003cstrong\u003eNR-311 uses DCEN\u003c\/strong\u003e and carries an E70T-7 classification. \u003cstrong\u003eNS-3M uses DCEP\u003c\/strong\u003e and carries an E70T-4 classification. NS-3M delivers slightly higher deposition rates and superior resistance to porosity on sulfur-contaminated steel due to its higher aluminum content. Neither wire has specified CVN impact toughness. Always verify polarity on your machine before switching between these two products.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \u003cdiv itemscope itemprop=\"mainEntity\" itemtype=\"https:\/\/schema.org\/Question\"\u003e\n    \u003ch3 itemprop=\"name\"\u003eCan NS-3M be used for multi-pass welding?\u003c\/h3\u003e\n    \u003cdiv itemscope itemprop=\"acceptedAnswer\" itemtype=\"https:\/\/schema.org\/Answer\"\u003e\n      \u003cp itemprop=\"text\"\u003eYes — NS-3M is suitable for both single and multiple-pass welding on carbon steel. It is recommended for welding 1\/8 in (3.2 mm) and thicker material. Inter-pass temperature should be managed according to the applicable code (typically 450–500 °F maximum for carbon steel without special requirements). Do not use NS-3M where CVN impact toughness properties are specified.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \u003cdiv itemscope itemprop=\"mainEntity\" itemtype=\"https:\/\/schema.org\/Question\"\u003e\n    \u003ch3 itemprop=\"name\"\u003eWhy does NS-3M resist porosity on sulfur-bearing steel?\u003c\/h3\u003e\n    \u003cdiv itemscope itemprop=\"acceptedAnswer\" itemtype=\"https:\/\/schema.org\/Answer\"\u003e\n      \u003cp itemprop=\"text\"\u003eNS-3M's flux core contains elevated aluminum (1.3–1.5 % typical in the weld deposit), which acts as a powerful deoxidizer and desulfurizer. Aluminum reacts preferentially with oxygen and sulfur in the weld pool, preventing the formation of gas pockets (porosity) that would otherwise occur when welding steels with high S content or surface contamination. This is why Lincoln Electric recommends NS-3M specifically for steel containing sulfur or contaminants.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cp\u003eBrowse the full \u003ca href=\"\/collections\/welding-wire\"\u003ewelding wire collection\u003c\/a\u003e or compare to \u003ca href=\"\/products\/lincoln-innershield-nr-311-fcaw-s-welding-wire\"\u003eInnershield NR-311 (E70T-7, DCEN)\u003c\/a\u003e for standard high-deposition flat\/horizontal work, or \u003ca href=\"\/products\/lincoln-outershield-71-elite-fcaw-g-welding-wire\"\u003eOutershield 71 Elite\u003c\/a\u003e when a gas-shielded FCAW-G option is preferred.\u003c\/p\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What AWS classification is Lincoln Innershield NS-3M?\",\n      \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"NS-3M is classified as E70T-4 per AWS A5.20 and E70T4-AZ-CS3 per AWS A5.36. The T-4 designation is a self-shielded electrode for maximum deposition in flat and horizontal positions, with no specified CVN impact toughness requirement.\"}\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What polarity does NS-3M use?\",\n      \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"NS-3M uses DCEP (DC Electrode Positive), also called reverse polarity. This is different from NR-311 which uses DCEN. Verify polarity before running any Innershield electrode.\"}\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How is NS-3M different from NR-311?\",\n      \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Both are high-deposition, flat\/horizontal, self-shielded FCAW-S wires. NR-311 uses DCEN (E70T-7); NS-3M uses DCEP (E70T-4). NS-3M delivers higher deposition rates and superior resistance to porosity on sulfur-contaminated steel due to its higher aluminum content.\"}\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can NS-3M be used for multi-pass welding?\",\n      \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Yes — NS-3M is suitable for both single and multiple-pass welding on carbon steel 1\/8 in and thicker. Do not use where CVN impact toughness properties are specified.\"}\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Why does NS-3M resist porosity on sulfur-bearing steel?\",\n      \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"NS-3M's flux core contains elevated aluminum (1.3-1.5% typical), which acts as a powerful deoxidizer and desulfurizer, preventing porosity when welding steels with high sulfur content or surface contamination.\"}\n    }\n  ]\n}\n\u003c\/script\u003e\n","brand":"Lincoln Electric","offers":[{"title":"5\/64 in · 50 lb Coil","offer_id":43638054518935,"sku":"ED012740","price":366.55,"currency_code":"USD","in_stock":true},{"title":"5\/64 in · (4) 14 lb Coil","offer_id":43638054224023,"sku":"ED012739","price":467.27,"currency_code":"USD","in_stock":true},{"title":"3\/32 in · 50 lb Coil","offer_id":43638053535895,"sku":"ED012736","price":350.91,"currency_code":"USD","in_stock":true},{"title":"3\/32 in · 600 lb Speed-Feed Drum","offer_id":43638053044375,"sku":"ED012735","price":4586.23,"currency_code":"USD","in_stock":true},{"title":"0.120 in · 50 lb Coil","offer_id":43638052421783,"sku":"ED012732","price":350.91,"currency_code":"USD","in_stock":true},{"title":"0.120 in · 600 lb Speed-Feed Drum","offer_id":43638052126871,"sku":"ED012731","price":4201.81,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0628\/7140\/4695\/files\/lincoln-ed012731-innershield-ns-3m-flux-cored-fcaw-s-welding-wire-0-120-in-600-lb-speed-feed-drum-lincoln-electric.jpg?v=1766432812","url":"https:\/\/weldingmart.com\/products\/lincoln-innershield-ns-3m-fcaw-s-welding-wire","provider":"WeldingMart.com","version":"1.0","type":"link"}