796F70 - Weldcraft 796F70 Long Lava Cup #3 (3/16") for 9/20 Torches - 10 Pack

Technical Overview of the Weldcraft 796F70 Long Lava Nozzle

The Weldcraft 796F70 is a specialized TIG welding nozzle designed to address specific thermal challenges encountered in industrial fabrication. Classified as a #3 size cup with a 3/16-inch (4.8mm) orifice, this consumable is manufactured from Lava, a distinct ceramic material chosen for its unique thermal properties compared to standard high-alumina cups. The nozzle features an extended length of 1-7/8 inches, categorizing it as a "Long" nozzle within the Series 2 consumable ecosystem. It is engineered for compatibility with air-cooled torches such as the WP-9 and water-cooled models like the WP-20, WP-22, and WP-25.

The primary engineering advantage of the 796F70 lies in its material composition. Standard alumina nozzles are manufactured by firing in ovens at approximately 3000°F, which causes significant shrinkage (up to 18% in length and 27% in diameter). While durable under normal conditions, alumina is susceptible to thermal shock in confined spaces. When a nozzle is used in a tight corner, excessive heat is reflected from the workpiece back into the ceramic. This rapid influx of energy causes the material to expand. Upon arc termination, the nozzle cools and contracts. The differential between this expansion and contraction often exceeds the tensile limits of alumina, resulting in immediate breakage or hairline fractures. Lava nozzles, like the 796F70, possess a coefficient of thermal expansion and a structural porosity that accommodates this thermal cycling much more effectively, making them the mandated choice for applications involving high reflective heat.

In addition to its thermal resilience, the physical geometry of the 796F70 serves a critical function. The elongated body allows the tungsten electrode to be extended further while maintaining adequate gas shielding, or simply allows the torch head to remain at a distance while the nozzle enters a recess. This is essential for root passes in pipe welding or fillet welds in complex assemblies where standard length cups would be obstructed by the surrounding base metal. By utilizing the Weldcraft 796F70, operators can maintain the correct torch angle and arc length in difficult-to-access zones without compromising the integrity of the shielding gas envelope.