To provide welding flux capable of preventing the moisture absorption by the welding flux, being stored for a long time and preventing the soundness in a weld zone from being deteriorated caused by moisture absorption at the time of working.
A coating layer 21 capable of holding an air film at the time of sinking under water is formed on a surface of spherical or general lump-like fine powder flux. The surface of flux powder is coated by coating agents, besides the inner part of flux powder is penetrated by them. In such a manner, the moisture absorption by the welding flux is prevented and the welding flux which is not affected by the variation of humidity and weather is obtained. Thus, storage equipment costs are reduced, the deterioration of flux caused by water absorption at site is decreased, and the soundness in a weld zone is improved. For example, the flux having an air film holding function under water is easily manufactured just only by adding a container for coating agents and coating device to the end of a conventional flux manufacturing process.
KOMORI MITSURU
MATSUMOTO YOSHIAKI
