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4623R - AccuLock Nozzle Insulator for MDX-250 and BTB Guns

Packaging: 5 pc per pack
$17.26/ea $61.20/5 pc per pack only $12.24/eaSave 29%

In stock

OVERVIEW

Technical Overview of the Bernard 4623R AccuLock Nozzle Insulator

The Bernard 4623R AccuLock™ Nozzle Insulator is a specialized component engineered to maintain the electrical and thermal integrity of high-performance MIG welding guns. Designed as a core element of the AccuLock™ consumable ecosystem, this insulator serves as the critical interface between the gas diffuser and the outer nozzle. It is manufactured from a high-temperature composite material capable of withstanding the intense radiant heat and spatter associated with industrial MIG welding applications. The 4623R is specifically calibrated to fit the neck geometry of Miller® MDX-250 and MDX-250 EZ-Select™ MIG guns, as well as the Bernard™ BTB™ (Best of the Best) series of semi-automatic air-cooled guns.

One of the defining technical features of the 4623R insulator is its cross-platform compatibility. It is engineered to seat correctly over both AccuLock™ S and AccuLock™ MDX gas diffusers. This interoperability allows fabrication environments to standardize on a single insulator part number even if they utilize a mix of Miller MDX and Bernard BTB equipment. The insulator functions by electrically isolating the electrically live contact tip and diffuser from the external nozzle (when using slip-on nozzles that require insulation) or simply providing the seating surface for the nozzle assembly. This isolation is paramount to preventing arc-out events where the nozzle accidentally contacts the workpiece.

Furthermore, the dimensional precision of the 4623R contributes to the overall concentricity of the AccuLock system. By ensuring the nozzle is perfectly centered around the contact tip, the insulator aids in maintaining a laminar shielding gas flow, reducing turbulence and the risk of porosity in the weld pool. For maintenance and repair operations (MRO), the 4623R represents a genuine OEM replacement part that restores the gun to factory specifications. It is essential for users to verify their gun model, as this specific insulator is tailored for the 250-amp range MDX guns and configurable BTB guns, ensuring a secure fit that resists loosening during thermal cycling.

Additional Information
Brand:Bernard, Miller
Item:Insulator
Fits Which Model:Miller MDX-250, Miller MDX-250 EZ-Select, Bernard BTB Series
Packaging Description:1 per each
Product Type:Nozzle Insulator
Consumable System:AccuLock S, AccuLock MDX
Compatibility:MIG Welding Guns

INCLUDED

  • 1 x Bernard AccuLock Nozzle Insulator (4623R)

APPLICATIONS

  • General Fabrication
  • Automotive Repair
  • Industrial Manufacturing
  • Structural Steel Welding
  • Maintenance and Repair Operations (MRO)
  • Shipbuilding

FAQ

The 4623R insulator is designed for Miller® MDX-250, Miller® MDX-250 EZ-Select™, and Bernard™ BTB™ series MIG welding guns.

Yes, the 4623R nozzle insulator is compatible with both AccuLock™ S and AccuLock™ MDX gas diffusers.

The insulator protects the nozzle from electrical current and helps align the nozzle for proper gas flow. Replacing it when worn prevents shorts and weld defects.

Yes, this is a genuine Bernard/Miller component, ensuring correct fit and material specifications for your equipment.

The manufacturer specifies this part for the MDX-250 and MDX-250 EZ-Select. The MDX-100 typically uses different consumables; please check your manual for MDX-100 specific parts.

It is constructed from a high-temperature resistant composite material designed to withstand welding heat and spatter.

This item is typically sold as a single unit (1 per package), though bulk packs may exist under different listings.

Yes, if your gun setup requires a nozzle and insulator for the specific flux-cored application (e.g., gas-shielded flux core), this insulator functions to hold the nozzle in place.