NT® Flux-cored wires

Flux-cored wire electrodes: “open arc” and submerged arc

Flux-cored wire electrodes: MAG and submerged arc

Flux-cored wire electrodes chemical resistant: MAG joint welding

Flux-cored wire electrodes: copper and copper alloys

Flux-cored wire electrodes

Besides welding of joints, the use of flux-cored wire electrodes for weld surfacing is steadily increasing. The advantages are associated primarily with the manufacture of the wires. For instance, the production of flux-cored wire electrodes with significantly higher contents of alloying elements is simpler than the production of solid wire electrodes with comparable contents. This applies especially to increased carbon contents. Stellite flux-cored wire electrodes, for instance, can be produced with carbon contents up to 2.5 per cent, whereas the manufacture of solid wires with such high carbon contents is not feasible. A further advantage of flux-cored wire electrodes is the possibility of producing them economically on short notice and in small lots. Thus, these wires are also available for research purposes and even for the development of new solid wires.

In addition to alloying elements and deoxidants, flux-cored wires also contain a certain fraction of basic slag components. In combination with basic welding powders, these components ensure a high degree of metallic purity in the resulting weld metal.

In general, the use of flux-cored wire electrodes in MIG welding offers the possibility of combining enhanced efficiency of the process with other technological advantages. Since the melting characteristics differ from those of solid wire electrodes, and since the drops are formed in a special way, the deposition efficiency thus achieved is higher, the resulting process is more economical, and overheating of the weld pool is less severe. Moreover, the natural weaving motion of the arc affects the fusion behaviour of the side walls in such a way that optimal side-wall fusion and thus high quality of the welded joint can be achieved with low energy input.

Seamless flux-cored wires have become established, especially for welding of joints. In contrast to flux-cored wires with a folded cross-section, seamless wires are characterised by a closed mantle, and the inner core is thus protected against moisture during prolonged storage.