136-2516 - Tuffaloy C-2516 Spot Welding Electrode No. 5 Taper 4-Inch Length

Technical Overview of the Tuffaloy C-2516 Electrode

The Tuffaloy C-2516 is a premium resistance welding electrode designed for industrial spot welding applications. Part of the widely utilized "25 Series," this electrode features a standard 5/8-inch diameter shank and a No. 5 RWMA (Resistance Welder Manufacturers' Association) taper. The No. 5 taper ensures a secure, leak-proof fit in standard electrode holders, providing the mechanical stability and electrical contact necessary for high-current welding cycles. With an overall length of 4 inches (indicated by the "16" in the part number, representing sixteen quarter-inches), this tip offers extended reach, making it suitable for welding geometries that require clearance away from the holder.

The "C" designation in the part number refers to the nose geometry. The Type C nose is a pointed design, which is critical for applications requiring high current density at the weld interface. The pointed shape helps to concentrate the welding force and current into a small area, facilitating the rapid formation of the weld nugget while minimizing the heat-affected zone in the surrounding base metal. This geometry is particularly effective for welding sheet metal where precise alignment and localized heating are required.

A distinguishing feature of Tuffaloy electrodes is their surface finish. As noted in the product specifications, these electrodes undergo a specialized passivation process. This chemical treatment removes surface contaminants and creates a barrier against excessive oxidation. For resistance welding, surface oxide is a detriment as it increases contact resistance, leading to arcing, surface expulsion, or inconsistent weld quality. The bright, shiny finish of the C-2516 is not merely cosmetic; it is an indicator of a clean, highly conductive surface ready for immediate use without the need for pre-cleaning or dressing.

Manufactured from high-grade copper alloy (typically Class 2 Chrome Copper for standard applications), this electrode balances electrical conductivity with physical hardness. This ensures that the tip retains its shape under the high compressive forces of the welding cycle while effectively dissipating heat to prevent mushrooming and prolong service life.