Flux-cored welding wire is made out of thin strip rolled into round or shaped steel tubing, with the filling of powder of certain extent, then into seam flux cored welding wire through drawing, or seamless flux-cored welding wire with tubes filling completely with powders. Flux cored welding wire can be with seams or without seams according to manufacture procedures. Welding with this wire has good welding deposition efficiency, good adaptability of steel and wide range of uses. This wire is mainly used for carbon dioxide gas shielded welding, submerged arc and electroslag welding. The powder flux cored wire electrode composition contains slag, building gas and solid components of the flux-cored wire arc welding without shielding gas.