Filler Wires
Filler wire is the consumable fed into a MIG/MAG or TIG weld, solid spooled wire for MIG/MAG and straight-length rod for TIG, and both have to match the base metal's chemistry, not just its general grade. NLS sources carbon steel MIG wire to AWS A5.18, low-alloy wire to AWS A5.28, and TIG filler rod to ISO 636.
Filler wire and filler rod do the same job as a stick electrode, adding metal to the joint, but in a different physical format that changes how the process runs. MIG/MAG wire comes wound on a spool and gets pushed continuously through the torch by a wire feed unit, so its diameter, copper coating, and how cleanly it feeds off the spool all affect arc stability as much as its chemistry does. TIG filler rod is a straight, cut-to-length rod fed into the weld pool by hand, so it doesn't need a feed mechanism, but its surface has to stay clean, since any oil or oxide picked up before use ends up straight in the weld.
NLS sources solid carbon steel MIG wire to AWS A5.18, the ER70S-6 grade and similar being the common structural fabrication choice, copper-coated for feedability and corrosion resistance in storage. Low-alloy wire and rod under AWS A5.28 covers higher-strength and low-temperature applications where a plain carbon steel filler wouldn't meet the joint's mechanical requirement, common on pressure equipment and structural steel graded above the basic carbon range. TIG filler rod is sourced to ISO 636, covering non-alloy and fine-grain steel rod in standard 1000mm lengths and multiple diameters, matched to the tungsten electrode size and joint thickness being welded.
On Saudi fabrication work, MIG wire in the ER70S-6 class covers most structural steel and general shop welding, while low-alloy A5.28 wire gets specified where a project's steel grade or service temperature pushes past what standard carbon steel filler can deliver. TIG rod sees the heaviest use on stainless piping, precision equipment fabrication, and any thin-material or root-pass work where an inspector will check the weld closely, since TIG generally produces the cleanest, most controllable weld of the common processes.
NLS quotes filler wire and rod against the AWS or ISO classification a project's WPS calls for, diameter, and quantity by spool weight or rod count, and returns a priced quote in USD. Standard ER70S-6 MIG wire in common diameters typically sources faster than low-alloy A5.28 wire or less common TIG rod diameters, which more often run on a manufacturer-confirmed lead time.
Specifications
- ✓MIG/MAG wire: AWS A5.18 carbon steel (ER70S-6 and similar), copper-coated spooled wire
- ✓Low-alloy wire and rod: AWS A5.28, for higher-strength and low-temperature service applications
- ✓TIG filler rod: ISO 636 classification, standard 1000mm cut lengths
- ✓Diameter range: 0.8mm to 1.6mm for MIG wire, 1.6mm to 4.0mm for TIG rod
- ✓Packaging: MIG wire on 5kg to 15kg spools, TIG rod in tubes by diameter
- ✓Selection basis: base metal chemistry and WPS classification, not general grade alone
Frequently Asked Questions
What's the difference between MIG wire and TIG filler rod?+
MIG wire is a continuous spooled wire fed automatically through the torch by a wire feed unit, sized and copper-coated for smooth, uninterrupted feeding. TIG filler rod is a straight, cut-length rod fed into the weld pool by hand, used with a separate tungsten electrode that strikes the arc. They're not interchangeable between processes even at the same nominal grade.
When does a project need AWS A5.28 low-alloy filler wire instead of standard A5.18?+
A5.28 applies when the base metal's grade or the joint's service condition, higher strength steel or low-temperature service, exceeds what a standard carbon steel A5.18 filler can deliver in the deposited weld. The WPS and base metal certificate determine which classification a joint requires; it's not a discretionary upgrade.
Does NLS supply TIG filler rod for stainless steel?+
Yes. NLS sources TIG filler rod matched to stainless base metal in addition to the carbon steel and low-alloy range, quoted against the base metal grade and the WPS classification a project's welding procedure specifies.