BONDED FLUX FOR SINGLE FACE SUBMERGED ARC WELDING AND SINGLE FACE SUBMERGED ARC WELDING METHOD OF 570 MPA ATMOSPHERE CORROSION RESISTING STEEL FOR LARGE HEAT INPUT

摘要

PROBLEM TO BE SOLVED: To obtain a weld zone with excellent toughness by the flux in combination of a steel plate, a wire, and a groove filling alloy wherein the contents of Cu, Cr, and Ni satisfy a specific relation, Li, Cu, Cr, Ni, and the total of Cu, Cr, Ni are within a specific range, and a grain diameter of the iron powder containing a specific proportion. ;SOLUTION: A flux for 570 MPa atmosphere corrosion resisting steel contains, at wt%, 0.30-0.60% Cu, 0.45-0.75% Cr, and 0.05-0.70% Ni. The contents of Cu, Cr, Ni satisfy a formula I, a formula II, and a formula III respectively. The flux contains 0.05-1.0% Li, 0.60% or less Cu, 1.0% or less Cr, 1.0% or less Ni, 1.5% or less Cu+Ni. The contained iron powder comprises 5-20% of the grain diameter of 0.50 mm or less and 80% or more of 0.10-0.50 mm grain. In the formulas, [Cu]B- shows the contents of Cu, Cr, Ni in a steel plate, [Cu]W- in a wire, [Cu]A- in a groove filling iron alloy, and [Cu]F- in a flux.;COPYRIGHT: (C)1999,JPO