KP2743-1-75R - Lincoln Magnum PRO 550A MIG Nozzle, 3/4 Inch Bore, 1/8 Inch Recess

Heavy-Duty Lincoln Electric MIG Consumables

The Lincoln Electric KP2743-1-75R is a premium gas nozzle designed to meet the rigorous demands of high-amperage industrial welding. Engineered specifically for the Magnum PRO 550A series of semi-automatic welding guns, this nozzle is built to sustain continuous operation at currents up to 550 amps. The nozzle features a substantial 3/4-inch (19 mm) inner diameter (bore), which provides a wide umbrella of shielding gas coverage. This large bore is essential when welding at high parameters or on heavy plate, ensuring that the weld pool remains fully protected from atmospheric contamination.

One of the standout features of this nozzle is its 1/8-inch (3.2 mm) recessed tip relationship. By positioning the contact tip slightly back inside the nozzle, the design offers protection against accidental short-circuiting against the workpiece and helps shield the tip from excessive radiant heat. This configuration is particularly beneficial for spray transfer modes and flux-cored applications where higher heat inputs are common. The nozzle utilizes a thread-on connection mechanism, which guarantees concentric alignment with the contact tip and diffuser. This precise centering is critical for maintaining a stable arc and consistent gas flow.

Durability is a key focus of the Magnum PRO line. The KP2743-1-75R is nickel-plated, a finish chosen for its ability to resist spatter adhesion. In high-production environments, spatter buildup can block gas flow and cause turbulence; the nickel plating allows spatter to be easily removed, reducing downtime for cleaning. Additionally, the nozzle features coarse threads that resist seizing, ensuring that the nozzle can be easily unscrewed even after repeated heating and cooling cycles. This product is an essential component for fabricators relying on Lincoln's 550A platform for structural and heavy equipment manufacturing.