... type acid sintered flux; alkalinity is 0.5-0.8,spherical particles , granularity is 10-60mesh;it shows good welding performances :stable arc ... ,oilcans,ships and so on. · ATTENTION : a.Before welding,the welding flux should be baked at the temperature from 300 to 350 ... .b.Before welding,the weld metal must be cleared away impurities,such as rust,oil,moisture etc. SUBMERGED-ARC WELDING FLUX SJ501