摘要 |
PURPOSE:To improve the operability and working environment in packing of a flux and to obtain a flux-cored wire having no variance in packing by specifying the grain size of the granulated and baked flux and packing the flux into a pipe at an adequate apparent porosity. CONSTITUTION:Raw material power of a flux is granulated in such a way that the grain size (d) thereof satisfies the inside diameter of a pipe/4>=d>=250mum and thereafter the granules are baked. The flux is packed in the pipe so as to have <=15% apparent porosity and the pipe is drawn, by which a desired flux cored wire is obtd. Since the particle strength of the flux is high in this method, the rate of powdering during packing and drawing is small and since there is no deterioration of air permeability, the packing operation is satisfactorily accomplished. The porosity in the stage of packing is high and the smooth drawing is permitted as the grain size of the flux is larger than 250mum. |