Welding is an excellent method of connecting industrial materials and is applied to many products around us. However, the scope of its work is very broad and it takes a considerable amount of time to be recognized as a full-fledged welding engineer. The requirements for welding include whether the weld is finished as designed, whether the required function and strength are obtained, and whether the appearance of the weld is finished to the required level. The purpose of this study was to investigate the relationship between the welding engineer's work and the welding results. To this end, this study used SOM2 to visualize the similarity of the welding engineer's work and discussed the relationship between the results and the welding results.