NP552 - 2% Thoriated Tungsten Electrode .040" x 7" (Red Tip)

Industry Standard for DC TIG Welding

The 2% Thoriated Tungsten (EWTh-2) is the most commonly used tungsten electrode in North America, favored for its exceptional performance in DC Electrode Negative (DCEN) welding. This .040" diameter electrode is engineered for precision applications on ferrous metals, including mild steel, stainless steel, and various high-temperature alloys. The addition of 2% thorium oxide (ThO2) significantly improves the metallurgical properties of the tungsten, lowering the work function and allowing for easier electron emission.

One of the primary advantages of thoriated tungsten is its superior arc starting capability. Unlike pure tungsten, which can struggle to initiate an arc at lower amperages, the 2% thoriated blend provides instant ignition and a stable, focused arc column. This is particularly important when working with the .040" diameter size, which is often utilized for low-amperage welding on sheet metal or intricate parts. The electrode maintains a sharp point well, resisting the "balling" effect common with other tungsten types on DC, ensuring deep penetration and precise heat input control.

Welders prefer the Red Thoriated tungsten for its high current capacity and resistance to weld pool contamination. Because the electrode operates cooler than its pure tungsten counterpart, it degrades more slowly, resulting in longer service life and fewer interruptions for tip preparation. It is the preferred choice for critical welds on pipe, pressure vessels, and aerospace components where X-ray quality results are required.

Safety and Handling

It is important to note that thorium is a low-level radioactive material. While the risk is minimal during normal welding, safety precautions should be taken during grinding. We recommend using a dedicated tungsten grinder with dust collection or wearing appropriate respiratory protection to avoid inhaling grinding dust. Despite this, the performance benefits of 2% Thoriated tungsten keep it as a top choice for professional welders demanding the best in DC arc stability and control.