Tweco 1240-1200 Mig Welding Nozzle 450A 1/2 Inch Bore 2 Pack

Product Description

The TWECO 1240-1200 is a slip-on MIG welding nozzle engineered for heavy-duty applications on Tweco SprayMaster MIG guns rated up to 450 amps. Built from 122 DHP copper alloy tubing, the nozzle housing delivers reliable heat resistance and conductivity under sustained high-amperage weld cycles. The 1/2 inch bore and 3.21 inch length suit demanding spray-transfer and high-deposition processes. A recessed contact tip relationship of 0.125 to 0.156 inches accommodates longer electrical stick-out and protects the tip when nozzle-to-workpiece contact is likely. The part number is rolled-stamped on the outer surface for fast identification in busy shop environments. Sold in a 2-pack. Licensed welders and MIG technicians are the primary installers.

This nozzle is suited for medium to heavy-duty MIG welding applications operating up to 450 amps. Its slip-on fit seats over the metal spring of a standard gas diffuser without additional hardware. The recessed tip geometry makes it well-matched to tack, spot, and stitch welding passes where the nozzle is likely to contact the workpiece, as well as any application where a longer electrical stick-out reduces arc-start sensitivity. The 3-piece construction — copper alloy housing, solid brass insert, and G7 silicone insulator — provides a self-contained electrical isolation solution with no separate insulator required.

Key Features

• 122 DHP copper alloy housing cut and formed from copper alloy tubing for high conductivity and heat resistance
• Solid brass nozzle insert machined and crimped in place to slide over the gas diffuser metal spring
• G7 silicone nozzle insulator provides electrical insulation from the gas diffuser without a separate insulator
• Recessed tip relationship of 0.125 to 0.156 inches supports longer stick-out and nozzle-contact welding scenarios
• Part number rolled-stamped on outer surface for rapid identification
• 3-piece self-contained design reduces front-end component count
• Sold as a 2-pack

Compatibility

Designed for use with 450-amp Tweco SprayMaster MIG guns and fits standard Tweco gas diffusers accepting a slip-on nozzle.

Installation Notes

Installation is performed by qualified welders or MIG equipment technicians. Disconnect and de-energize the welding power source before servicing front-end consumables. Slide the nozzle over the gas diffuser spring until fully seated — do not force or over-torque. Inspect the nozzle insulator and insert for wear or spatter buildup at each consumable change to maintain proper electrical isolation and shielding gas flow.

Technical Specifications

• Bore Size: 0.5 inches
• Nozzle Length: 3.21 inches
• Outer Diameter: 0.875 inches
• Recessed Tip Relationship: 0.125 to 0.156 inches
• Amperage Rating: 450 amps
• Housing Material: 122 DHP Copper Alloy
• Insert Material: Solid Brass
• Insulator Material: G7 Silicone
• Attachment Type: Slip-On
• Weight: 0.21 pounds
• Quantity per Pack: 2

Standard Information

• Brand: TWECO
• Manufacturer Part Number: 1240-1200