57N75L - Weldcraft 57N75L Long Alumina Gas Lens Cup #6 (3/8")

Technical Overview of the Weldcraft 57N75L Alumina Nozzle

The Weldcraft 57N75L is a specialized TIG welding consumable designed to extend the reach and capabilities of standard air-cooled and water-cooled torches. Classified as a "Long" gas lens nozzle, this component features a #6 orifice, corresponding to a 3/8-inch (9.6mm) diameter bore. The defining characteristic of the 57N75L is its overall length of approximately 2-3/4 inches (69.8mm), which is significantly longer than standard alumina cups. This elongation is engineered to facilitate welding in areas with limited access, such as inside pipe manifolds, acute structural angles, or complex automotive exhaust assemblies.

Material composition is critical for TIG nozzles, and the 57N75L is constructed from high-purity alumina ceramic. This material is selected for its excellent dielectric strength, high thermal conductivity, and resistance to thermal shock. In high-amperage applications, the nozzle effectively withstands the intense heat of the arc without cracking or degrading, provided it is used within its rated duty cycle. The alumina surface also resists the adhesion of welding spatter, maintaining a clean orifice for consistent gas flow.

Compatibility is a key factor for industrial procurement. The 57N75L is designed to thread onto standard gas lens collet bodies (typically the 45V series) used in 17, 18, and 26 series TIG torches. It is not compatible with standard non-gas-lens collet bodies. The use of a gas lens system in conjunction with this long nozzle promotes laminar gas flow, which is essential when the operator requires an extended tungsten stick-out to see past the nozzle's length. This combination ensures that the weld pool remains protected from atmospheric contamination even when the torch is positioned at a distance from the workpiece.

For maintenance and operations (MRO) professionals, stocking the 57N75L ensures that welding operators have the necessary tooling to handle non-standard joint geometries. It is a direct replacement for industry-standard 57N75L part numbers across various brands, though the Weldcraft pedigree ensures adherence to tight manufacturing tolerances for thread engagement and concentricity.