LongTeng E309-16 Stainless Steel Welding Electrode

LongTeng E309-16 overview

LongTeng E309-16 is the higher-alloy stainless electrode in the LongTeng welding materials catalogue, listed by the manufacturer to AWS A5.4 E309-16. With roughly 24 percent chromium and almost 13 percent nickel in its reference chemistry, it is richer in both elements than the E308-16 grade printed beside it. That composition is what makes the class the usual first thought when a joint must connect two different materials, for example stainless steel to carbon steel, or when a stainless buffer layer is needed. The manufacturer’s own application text mentions welding similar type stainless steel, dissimilar stainless steel, and high chromium steel and high manganese steel.

Seven Star LLC supplies LongTeng consumables to customers in Oman and the wider GCC, handling stock enquiries and technical questions from Muscat. Below you will find the catalogue figures, labelled general knowledge about the class, and the route to the datasheet and batch certificate.

Figures listed by the manufacturer

These are typical values listed by the manufacturer for this grade. They are reference results, not a lot guarantee.

Yield strength and impact energy are not printed for this grade in the catalogue, so this page does not state them.

Reference chemistry

In percent, the catalogue lists carbon 0.055, manganese 1.45, silicon 0.70, sulphur 0.009, phosphorus 0.021, chromium 24.25, nickel 12.75, molybdenum 0.035 and copper 0.10. Compared with LongTeng E308-16, chromium is higher by about 4.5 points and nickel by about 3 points. Those additions are intended to give the deposit enough alloy content to tolerate dilution from the other metal in a mixed joint and still remain austenitic.

Welding current by diameter

The E309-16 class explained (general class information)

This section describes the AWS E309-16 class in general and is not a LongTeng guarantee. The 309 composition is designed to weld dissimilar metals, to join stainless steel to mild or low alloy steel, and to lay a transition or buffer layer before a matching stainless filler is applied. The extra chromium and nickel offset the dilution that occurs when the stainless deposit melts into carbon steel, and help the weld keep a duplex structure with a little ferrite, which resists cracking. The suffix 16 points to a lime-titania covering with a stable, smooth arc and an easily removed slag. For service above roughly 300 degrees Celsius or in strongly corrosive media, welding engineers decide on a case-by-case basis whether a 309 deposit is acceptable or whether another class is needed.

Uses suggested by the catalogue

• Welding stainless steels of a similar type.
• Joining dissimilar stainless steels.
• Welding high chromium steel and high manganese steel.
• Transition joints between stainless and carbon steel components, a common general use of this class.

Field practice (general guidance)

Dissimilar joints are less forgiving than ordinary ones, so preparation counts. Grind and clean both members separately, using stainless tools for the stainless side. Aim the arc a little toward the stainless member if the carbon steel side is much thicker, to balance heat. Keep heat input moderate and interpass temperature controlled. Electrodes should be stored dry and used from sealed packs; a few procedures call for light drying, which will be stated on the packaging. Chip the slag well. When the finished weld sits in corrosive service, a final clean-up or passivation may be specified by the project.

Why the alloy level matters

When a stainless filler melts into carbon steel, the weld pool is diluted and its chromium and nickel fall. A plain 308 deposit can end up too lean and may form hard, brittle microstructures, which is exactly the risk that an over-alloyed class is meant to absorb. LongTeng E309-16 starts from a higher chromium and nickel level, so some dilution can be tolerated while the weld stays mainly austenitic. That general metallurgy is the reason many welding procedures name this class for transition joints, and it is why buyers searching for LongTeng E309-16 are usually working on mixed-metal assemblies, repairs of unknown steel, or cladding transitions.

Selection tips

Specify LongTeng E309-16 when the drawing calls for an E309-type deposit, for dissimilar joints, or for a buffer layer. Use LongTeng E308-16 instead when both parts are 304-type stainless and no dilution from carbon steel is involved. Because the catalogue prints no yield or impact figures for either electrode, any design that depends on them needs the batch test certificate, and our team can ask for it.

Welding set-up pages that may help are the Lincoln Electric Power Wave S500, the ESAB Rebel EMP 285ic and, for rotating equipment maintenance, the KOBELCO rotor assembly. Confirm that the power source supports DC electrode positive stick welding at the amperage you plan to use with LongTeng E309-16.

Datasheet and ordering

The catalogue extract that contains LongTeng E309-16 is attached to this page and also includes E308-16, because both grades share one printed page. Send us the diameter, quantity, destination and certificate requirement and Seven Star LLC will reply with a quotation. Packaging and delivery are confirmed per order. No approval is claimed on this page for this grade. Ask for the LongTeng E309-16 datasheet to read the full table, and ask for the batch certificate before you buy LongTeng E309-16 for critical joints. Keep it labelled and separate from carbon steel electrodes in your store.

If you are unsure whether LongTeng E309-16 suits your base metals, send us the two material grades and the joint sketch, and we will review them against the catalogue before quoting.

Receiving and storage deserve a short checklist. On delivery, confirm that the carton marking shows the grade you ordered and the diameter, compare the batch number with the certificate, and keep the electrodes in a dry, ventilated room away from carbon steel consumables. For a critical weld, record the lot number so the finished joint made with LongTeng E309-16 can be traced to its paperwork later. Seven Star LLC is glad to help assemble that documentation package for your quality department.

In summary, LongTeng E309-16 is the catalogue answer for mixed-metal stainless joints; request the datasheet, check the batch certificate and decide with your welding engineer.