摘要
Abstract
The welding of thick steel plates is a core technology in large-scale engineering construction.Since the 1980s,China has gradually overcome the bottlenecks in thick plate welding technology.The welding technology related to the Na-tional Stadium"Bird's Nest"was awarded international authoritative awards,marking that China's technology in this field has reached an internationally leading level.However,problems such as a lack of theoretical understanding and irregular ap-plication of technology among some practitioners in the industry have led to frequent occurrences of engineering quality haz-ards and economic losses.Based on fundamental welding theories and engineering practice,this paper analyzes the mecha-nism of thick steel plate welding,discussing the causes and effects of segregation in both the base metal and weld seam.Fur-thermore,it introduces commonly used technical indicators,with a particular focus on the importance of controlling cooling rates(t8/5(t8/3),t100)for the performance of welded joints.It elaborates on the advantages of multi-layer,multi-pass stag-gered welding technology in reducing segregation,controlling line energy,and improving the comprehensive performance of welded joints.A combined welding process scheme of"backing weld(SMAW)-filler weld(GMAW)-cover pass(FCAW-G)"is proposed.The research results provide a theoretical basis and technical guidance for precisely controlling welding de-fects and enhancing the overall performance of thick plate welded joints,holding significant practical value for standardizing industry technological applications and reducing project losses.关键词
钢结构厚板焊接/偏析/控制指标/多层多道错位焊接/组合焊接工艺Key words
steel structure thick plate welding/segregation/control indicators/multi-layer,multi-pass staggered welding/combined welding process分类
矿业与冶金
