N-A5818C - Bernard AccuLock S Copper MIG Nozzle, 5/8" Bore, 1/8" Recess

Technical Overview of the Bernard N-A5818C AccuLock S Nozzle

The Bernard N-A5818C is a premium-grade MIG welding nozzle belonging to the AccuLock S series, specifically engineered for heavy industrial welding environments. This consumable is manufactured from high-conductivity copper, designed to withstand high-amperage applications while maintaining structural integrity and thermal efficiency. The nozzle features a 5/8-inch (15.875 mm) bore diameter, which provides a broad shielding gas envelope suitable for medium to high-current welding parameters, ensuring porosity-free welds on carbon steel, stainless steel, and aluminum.

A critical specification of the N-A5818C is its 1/8-inch (3.175 mm) tip recess. This recessed geometry positions the contact tip slightly inside the nozzle, offering protection against radiant heat and reducing the likelihood of short-circuiting against the workpiece. It is particularly effective in minimizing spatter adherence to the contact tip face, thereby extending the service life of the front-end consumables. The nozzle is designed to mate perfectly with AccuLock S gas diffusers (such as the D-MA250 or D-MA350), utilizing a coarse thread design that resists cross-threading and seizing.

Compatibility and System Integration

This nozzle is a core component of the AccuLock S consumable system and is fully compatible with the following MIG gun platforms:

• Bernard BTB Series MIG Guns: The standard industrial offering from Bernard, allowing for seamless integration into existing production lines.
• Miller MDX-250 MIG Guns: Provides an industrial upgrade path for users of the MDX-250, enhancing the gun's durability and performance.
• Miller MDX-250 EZ-Select MIG Guns: Fully compatible with the trigger-select versions of the MDX series.

The AccuLock S system employs a unique "Load and Lock" mechanism. A steel retaining ring on the gas diffuser engages with the nozzle, preventing it from vibrating loose during operation—a common failure point in standard MIG guns. The tapered connection between the contact tip and diffuser ensures maximum electrical conductivity, reducing resistance heating and promoting a stable arc.