Fluxkärnad

Fluxkärnad is a term used in welding to describe a type of electrode in which a flux material is housed within a hollow metal tube, forming a flux-core wire. When welded, the flux core decomposes to provide shielding gas or slag, and to introduce alloying elements that improve weld quality. The concept is closely associated with flux-cored arc welding (FCAW).

There are two main variants. Self-shielded fluxkärnad FCAW-S relies primarily on the flux decomposition to shield the arc, making external shielding gas unnecessary. Gas-shielded fluxkärnad FCAW-G uses an external shielding gas in addition to the flux core. The choice between these variants depends on work conditions, such as indoor versus outdoor welding and the presence of wind.

Construction and composition vary by manufacturer and application. The outer sheath is usually a metallic tube with a flux core that may contain deoxidizers, alloying elements, and slag formers. Flux formulations influence slag characteristics, weld penetration, mechanical properties, and the level of spatter. Typical wire diameters range from about 0.8 to 1.6 millimeters.

Applications and advantages. Fluxkärnad wires are widely used for welding ferrous metals, offering high deposition rates and good performance on dirty or rusty surfaces. They are favored in construction, shipbuilding, and pipeline work for their compatibility with portable equipment and their tolerance to less-than-perfect joint fit.

Limitations and safety. Slag must be chipped or brushed away after welding, and fumes from flux materials require proper ventilation and personal protective equipment. Overall, fluxkärnad represents a versatile option in arc welding, balancing ease of use with robust weld characteristics.