Tweco 1240-1856 Mig Welding Nozzle 1/2 Inch Bore

Product Description

The TWECO 1240-1856 is a medium duty MIG welding nozzle with a 1/2 inch bore, designed for use with Tweco Velocity-series MIG gun consumable systems. It uses a single-thread design that replaces the two- or three-thread configurations found on typical MIG nozzles, which reduces seizing, cross-threading, and hand-tool dependency during consumable changes. The threaded interface pairs brass nozzle threads against heat-treated stainless steel gooseneck threads. Brass against stainless creates a soft-on-hard engagement that grips firmly without locking up under heat. Licensed welders and fabrication shops running production or repair MIG operations will find the tool-free changeout practical on the floor.

This nozzle is suited for medium duty MIG welding applications in fabrication, maintenance, and repair environments. The 1/2 inch bore accommodates standard wire diameters run at medium duty amperage levels. It is sold individually and is intended for replacement of worn or damaged nozzles on compatible Tweco Velocity MIG gun assemblies. The fixed threaded configuration maintains a consistent flush relationship between the nozzle opening and the contact tip, which supports repeatable arc positioning across weld passes.

Key Features

• Single-thread design reduces seizing and cross-threading compared to two- or three-thread nozzle systems
• Brass nozzle threads engage heat-treated stainless steel gooseneck threads for a grip that resists loosening under heat
• Fixed threaded style maintains consistent flushness between nozzle opening and contact tip
• Tool-free nozzle replacement speeds consumable swaps during production welding
• Medium duty rating suits standard fabrication and repair MIG applications
• 1/2 inch bore accommodates common wire diameters used at medium duty output levels

Compatibility

Designed as an OEM-style replacement nozzle for Tweco Velocity-series medium duty MIG gun assemblies using the single-thread consumable interface.

Installation Notes

Nozzle replacement on MIG guns should be performed with the welder powered down and the wire feeder disabled. Allow the gun and nozzle to cool fully before handling to avoid burns from residual heat. Thread the nozzle onto the gooseneck by hand until snug — no tools are required or recommended for this design. Inspect the contact tip and gas diffuser for wear before reinstalling the nozzle.

Technical Specifications

• Bore Size: 1/2 inch
• Duty Rating: Medium Duty
• Height: 2.25 inches
• Width: 1 inch
• Length: 1 inch
• Weight: 0.17 pounds
• Thread Material (Nozzle): Brass
• Thread Material (Gooseneck): Heat-treated stainless steel
• Unit of Measure: Each
• Minimum Order Quantity: 2
• UPC: 608246434247

Standard Information

• Brand: TWECO
• Manufacturer Part Number: 1240-1856