Tweco 1240-1240 Heavy Duty Mig Nozzle 450A 0.5 in Bore

Product Description

The TWECO 1240-1240 is a heavy-duty MIG welding nozzle designed for demanding welding applications up to 450 amps. Built with a 3-piece construction, it includes a nozzle housing cut and formed from copper alloy tubing, a nozzle insert machined from solid brass, and a nozzle insulator constructed from G7 silicone material. The 0.5-inch bore fits standard gas diffusers, and the nozzle measures 3.29 inches in length with a 1.117-inch outer diameter. A recessed contact tip relationship of 0.125 to 0.156 inches provides extended electrical stick-out for specific welding techniques. The part number is rolled and stamped on the outer surface for quick field identification. Sold in a pack of 2.

This nozzle is suited for medium to heavy-duty MIG welding operations in industrial, fabrication, and manufacturing environments. The recessed tip configuration is appropriate for higher-heat applications, tack welding, spot welding, and stitch welding, or in situations where the nozzle may contact the workpiece. The nozzle insert slides over the metal spring of the gas diffuser, and the G7 silicone insulator provides the required electrical isolation from the gas diffuser without needing an additional insulator. Licensed welders and professional fabricators working with high-amperage MIG equipment will find this nozzle a direct-fit replacement for standard gas diffuser setups.

Key Features

• Rated for welding applications up to 450 amps
• 3-piece design: copper alloy housing, solid brass insert, and G7 silicone insulator — no additional insulator required
• Recessed contact tip relationship of 0.125 to 0.156 inches for extended electrical stick-out
• Nozzle housing made from 122 DHP copper alloy for durability and heat resistance
• Part number rolled and stamped on outer surface for easy identification
• Fits standard gas diffuser; nozzle insert slides over diffuser metal spring
• Sold as a 2-piece pack

Compatibility

Designed as a heavy-duty OEM-style replacement nozzle for MIG welding guns using standard gas diffusers with a 0.5-inch bore, rated for medium to heavy-duty applications up to 450 amps.

Installation Notes

Installation should be performed by a qualified welder or welding technician. Ensure the welding machine is powered down and the gun is fully cooled before replacing the nozzle. Slide the nozzle insert over the metal spring on the gas diffuser until seated, and verify the insulator is properly positioned to maintain electrical isolation. Do not operate at amperage levels exceeding the 450-amp rating of this nozzle.

Technical Specifications

• Bore Size: 0.5 inches
• Nozzle Length: 3.29 inches
• Outer Diameter: 1.117 inches
• Maximum Amperage: 450 A
• Recessed Tip Relationship: 0.125 to 0.156 inches
• Nozzle Housing Material: 122 DHP copper alloy
• Nozzle Insert Material: Solid brass
• Nozzle Insulator Material: G7 silicone
• Package Weight: 0.58 pounds
• Package Dimensions: 3.4 x 1.1 x 1.1 inches
• Quantity per Pack: 2
• UPC: 608246300979

Standard Information

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