LongTeng EM12 Carbon Steel Submerged Arc Welding Wire

LongTeng EM12 at a Glance

The manufacturer’s catalogue gives LongTeng EM12 its own entry among the submerged arc wires, with the conformance line AWS A5.17 EM12 and a reference to the sintered flux SJ101. It is a bare, copper-coated steel wire sold on coils and in drums, and the printed diameters are 2.5, 3.2, 4.0 and 5.0 mm. According to the listing, the wire serves high speed welding of steel plate in the 420 MPa tensile class and filling welding in multi-pass grooves.

Seven Star LLC supplies LongTeng consumables from Muscat to structural fabricators, tank builders and EPC subcontractors across Oman and the Gulf. Every figure on this page is taken from the catalogue entry, and we label it as a typical value listed by the manufacturer so that engineers can see exactly what is claimed and what is not.

Reading the EM12 Class Name

General class information: in AWS A5.17 the second letter of a carbon steel SAW wire shows manganese content, with M standing for the medium level, and the number shows nominal carbon in hundredths of a percent. EM12 therefore points to a medium-manganese wire with about 0.12 percent nominal carbon. The printed analysis for LongTeng EM12 shows 0.96 percent manganese and 0.066 percent carbon, which sits in the same family of values. This explanation describes the class system only; it is not an additional promise from LongTeng.

Compared with the low-manganese EL8 entry on the same catalogue page, a medium-manganese wire carries more deoxidising and strengthening alloy into the weld pool, so the deposit is generally somewhat stronger. The catalogue states the property targets as ranges and minimum values for this grade, rather than single measured numbers.

Process Notes for Submerged Arc Work

Submerged arc welding buries the arc under a blanket of granular flux. Heat transfer is efficient, penetration is deep and the finished bead is smooth, so the method suits thick plate and long continuous seams made in the flat or horizontal position. With LongTeng EM12 the catalogue recommends sintered flux SJ101. Sintered fluxes are generally stored sealed and dried before use, because absorbed moisture raises hydrogen in the weld; follow the flux manufacturer’s handling sheet.

Wire diameter changes the character of the weld. Thinner wire at the same current gives higher current density and deeper penetration, while 4.0 and 5.0 mm wire carries heavy current for high deposition. No current or voltage ranges are printed for this grade, so parameters have to come from your qualified procedure and not from this page.

Good wire handling matters as much as the grade itself. Coils and drums should stay in their sealed packaging until they are loaded, rust or oil on the copper coating should be avoided, and the feed path from drum to contact tip should be clean and free of sharp bends. Poor feeding shows up as arc instability long before it shows up as a metallurgical problem, and a stable arc is what lets the printed properties be reproduced in the workshop.

What the Manufacturer Lists for LongTeng EM12

• Conformance to AWS A5.17 EM12, listed with the flux SJ101.
• Tensile strength range of 415 to 550 MPa.
• Minimum yield strength of 330 MPa and minimum elongation of 22 percent.
• Minimum impact energy of 27 J at a test temperature of minus 20 degrees Celsius.
• A very low sulphur figure of 0.007 percent and phosphorus of 0.010 percent in the printed analysis.
• Four wire diameters: 2.5, 3.2, 4.0 and 5.0 mm.
• Application note covering high speed welding of 420 MPa class plate and filling welding.

Where LongTeng EM12 Fits in Gulf Fabrication

Pressure vessel and heat exchanger shells, wind tower sections, pipe mill seams and structural girders are typical places where a medium-manganese SAW wire is chosen. In the Sultanate, such work is common around Sohar, Salalah and Duqm, where large steel items are rolled and welded before being shipped to oil, gas and water projects. The minimum impact value at minus 20 degrees Celsius in the catalogue is relevant for projects that specify low-temperature toughness tests.

As with every consumable, a buyer using LongTeng EM12 should perform a procedure qualification on production-grade plate, because plate chemistry, heat input and interpass temperature all change the final result. Ask Seven Star LLC for the manufacturer’s batch certificate when you place an order, and we will pass your technical questions to the manufacturer.

When a project calls for a wire in the same family but with a different strength level, the neighbouring grades on the catalogue pages are worth comparing side by side, and our team can send the corresponding extracts so that the choice is made from printed data and not from memory.

Specification Table

These are typical values listed by the manufacturer for LongTeng EM12.

Pack Sizes in the Catalogue

The package reference section shows submerged arc coils of 25, 50, 100, 250 and 350 kg and drums of 150, 250 and 350 kg. They are reference packages from the manufacturer, not a stock list. Tell us the pack that fits your wire feeder and we will confirm what can be offered for LongTeng EM12.

Related Products

Welding departments also need machines and cable. Browse the ESAB Rebel EMP 285ic, the Lincoln Electric Power Wave S500 or the Hawke 501/421 industrial cable gland, or return to the submerged arc wire category.

Call To Action

Send Seven Star LLC your diameter, quantity and pack preference to request a quotation for LongTeng EM12. The datasheet extract on this page shows the printed values for LongTeng EM12 next to its sibling grade, and the manufacturer’s test certificate can be requested with the order.