The invention discloses a low-
alloy corrosion-resistant
welding wire and a
welding method, and relates to the technical field of
welding. The low-
alloy corrosion-resistant welding wire comprises the following chemical components: 0.03%-0.10% of C, 0.2%-0.3% of Si, 0.8%-2.4% of Mn, 0%-1.5% of Ni, 0.4%-1.5% of Cr, less than or equal to 0.005% of S, less than or equal to 0.005% of P, less than or equal to 0.02% of Als and Fe. The components of the welding wire do not comprise
alloy elements such as Cu, Mo and Ti, a proper amount of Cr and Ni are added, and the compactness of a welding line
rust layer, especially the compactness of an inner
rust layer can be remarkably improved by adding Cr into the welding wire, so that the welding wire has excellent
corrosion resistance; and by adding a proper amount of
Ni element, grains can be refined, so that the structure is more easily converted into
acicular ferrite, and the
toughness of a welding seam is improved. By the adoption of the welding wire, the
impact toughness of obtained
weld metal reaches 80% or above of that of low-alloy corrosion-resisting steel, under the flowing accelerated corrosion condition, the corrosion step of the weld and a
heat affected zone /
base metal is smaller than 30 microns, the flowing medium corrosion resistance and
impact resistance of a steel
pipe are remarkably improved, and application and popularization of the low-alloy corrosion-resisting steel in a
heat supply pipe network are promoted.