LongTeng ER70S-6 Copper Free Solid MIG Welding Wire

LongTeng ER70S-6 Copper Free overview

LongTeng ER70S-6 Copper Free is listed as its own entry on page 6 of the manufacturer’s catalogue, directly below the standard copper-coated ER70S-6. The datasheet gives the AWS class as A5.18 ER70S-6 and describes it for welding low-carbon steel and all kinds of 500 MPa structural steel parts. The distinguishing feature is in the name: it is the copper free version of the grade.

General class information: a copper free wire is supplied without the thin copper plating that is applied to conventional MIG wire, and it is usually chosen where users want to avoid copper flaking in feed systems or copper pickup in the weld area. The catalogue does not explain the finish in detail, so ask for the manufacturer’s description if a customer specification depends on it. Seven Star LLC supplies it from Muscat for customers in Oman and the GCC.

Data printed for the copper free wire

The table repeats the figures on the datasheet as typical values listed by the manufacturer. We have deliberately left the carbon value out: the figure printed for carbon on this page is far below the neighbouring ER70S-6 line and does not look consistent with the grade, so we prefer to leave it out rather than risk a misleading figure.

Printed chemical composition for the other elements, weight percent:

Chemistry and mechanical comparison

Manganese of 1.54 percent and silicon of 0.88 percent keep this grade in the same deoxidiser class as the standard ER70S-6. Sulphur is 0.011 and phosphorus 0.012 percent, both marginally lower than the copper-coated version, and chromium, nickel, molybdenum and vanadium stay at trace level. The 0.15 percent copper figure is the residual copper analysis of the base wire.

The mechanical line is identical to the copper-coated entry: 555 MPa tensile, 450 MPa yield, 29 percent elongation and 77, 95 and 83 joules at minus 40 degrees Celsius. Identical values on two chemistries are plausible for the same class, but they should be checked against the certificate of each shipment.

Choosing between coated and copper free

General class information, not a LongTeng claim: bare or copper free wire can run cleaner through long conduits and robotic feeders because there is no coating to abrade, and contact tip deposits can be lower. Copper-coated wire on the other hand has long been the standard in manual welding. The right choice depends on the feeding system, the customer specification and the welding procedure.

If you are replacing one with the other on a qualified procedure, requalification or at least a documented check is usually required, because feeding behaviour and arc stability can differ even when the classification is the same.

Gas flow and current

The catalogue gives the same two reference gases as the coated grade, 100 percent CO₂ and 80 percent argon with 20 percent CO₂, and the same four diameters:

Applications

For LongTeng ER70S-6 Copper Free the manufacturer’s text mentions low-carbon steel and all kinds of 500 MPa structural steel parts. Possible fits include robotic cells for brackets and chassis parts, automated production lines, steel frame fabrication and the long continuous runs where feeding reliability matters, always according to your own welding procedure.

Contractors who run mechanised stations alongside manual machines such as the Lincoln Electric Power Wave S500 may keep both variants and assign them by process. Related solid wire grades are listed in our solid welding wire category.

Packaging and ordering

The manufacturer’s package reference lists GMAW spools to EN ISO 544 in several formats: BS300 (steel, 15 kg), D270 (plastic, 15 kg), D300 (plastic, 15 kg), D200 (plastic, 5 kg) and D100 (plastic, 1 kg), each in corrugated cardboard outer packing. These are the manufacturer’s reference packages, not a statement of what is on our shelves; confirm the spool format and quantity you need when you send the enquiry.

Contact Seven Star LLC with your required diameter, spool format and quantity of LongTeng ER70S-6 Copper Free, and the end-use code or procedure. We will confirm availability and send the datasheet extract. No third-party approval is claimed here for this grade; ask for the lot certificate when your project needs documentary proof.

Storage and feeding notes

General guidance, not a manufacturer instruction: copper free wire should be kept as carefully as any bare-surface steel wire, because a surface without plating can pick up moisture and form light rust sooner than a plated surface in damp air. Keep spools sealed, stored dry and off the floor, and open them only when they are about to be used.

Feeding hardware should be matched to the wire. Check drive rolls, liners and contact tips when you move to LongTeng ER70S-6 Copper Free from a plated wire, and record the settings that give a stable arc. This small test avoids blaming the wire for feeding problems that are really hardware problems.

Documentation for LongTeng ER70S-6 Copper Free

Request the batch test certificate when ordering LongTeng ER70S-6 Copper Free, especially for the carbon content that is not reproduced on this page. The datasheet extract downloadable from this product page shows exactly what the manufacturer printed, so you can compare it with the certificate. Seven Star LLC will forward any technical question about the finish or the chemistry to the manufacturer and will report back what we receive.

Where LongTeng ER70S-6 Copper Free sits in the range

On the datasheet page, LongTeng ER70S-6 Copper Free follows the standard ER70S-6 wire and shares its AWS class, gas options and diameters. The practical differences are the surface finish and the printed chemistry. Buyers who need a plated wire for manual work can choose the standard entry, while buyers who want to evaluate LongTeng ER70S-6 Copper Free for mechanised welding can request a trial spool quantity, subject to availability, and compare feeding behaviour and tip life on their own equipment.

Seven Star LLC works with fabricators, EPC contractors and maintenance teams in Muscat, Sohar and Salalah, and handles enquiries for LongTeng ER70S-6 Copper Free together with matching shielding gas and feeding accessories where the customer asks for them. Engineering questions about the wire, the datasheet extract or your procedure can be raised in the same enquiry, and we will respond with what the manufacturer documents confirm.

For piping packages that also use grooved joints, such as the Victaulic Style 107N QuickVic Rigid Coupling, we can handle the wire and the couplings in one reply.

In short, LongTeng ER70S-6 Copper Free is offered for buyers who want the ER70S-6 class in an uncoated finish, with the datasheet extract and the lot certificate as their reference documents.