Welding backing of CO2 vertical electrogas automatic one-side welding, and method for using same

A backing block is designed based on welding metallurgy characteristics of CO2 vertical electrogas automatic welding and demands of CO2 vertical electrogas automatic one-side welding on performances of backings. The backing comprises one or a plurality of backing blocks, and the backing blocks comprise raw material components of alumina, quartz, talcum, feldspar, porcelain clay, Suzhou black earth, white mud and titanium dioxide, wherein the weight ratio of each raw material component is: 20 to 40 of alumina, 10 to 20 of quartz, 10 to 15 of talcum, 5 to 10 of feldspar, 2 to 16 of porcelain clay, 10 to 20 of Suzhou black earth, 5 to 10 of white mud and 3 to 5 of titanium dioxide. The welding backing of the invention optimizes the welding metallurgy process of CO2 vertical electrogas automatic one-side welding, and provides better weld quality and welding performance than that of CO2 vertical electrogas automatic welding, so that the welding procedures are reduced, the welding materials are saved, the welding p