| 摘要 |
PURPOSE:To assure the fluidity of slag and to suppress generation of welding defects in multielectrode submerged arc welding by using a cored wire contg. a specific amt. of Al and Al-Mg alloy powder as a slag forming agent. CONSTITUTION:A cored wire contg. 0.5-7wt% powder of Al, Al-Mg alloy or a mixture composed thereof as a slag forming agent is used for at least one of welding wires in multielectrode submerged arc welding of a thin walled large diameter pipe, etc. The properties over the entire part of slag are maintained at a high viscosity by using such wire. A thermit reaction is caused in at least a part of a molten pool and the fluidity of slag is assured by utilizing the heat generated by the same, by which the generation of welding defects such as an undercut and slag inclusion is suppressed. |
