2010 年 28 巻 1 号 p. 39-47
As for steel frames of buildings, the welding of single bevel T-joints with steel backing is usually used.
Recently, there have been some experimental reports concerning 25 degree groove welding by semi-automatic arc welding. However it is not yet carried out in the actual field. The shortening of welding time leads to a reduction of emissions of greenhouse gas. Therefore, as this is an earth environment improvement, we expect this welding process in the steel frames of buildings to become attractive.
In the same way as semi-automatic arc welding, the welding of the first layer is one of the biggest problems for the narrow groove welding in steel frames of buildings by welding robots. In this study, we researched actual assembling precision of T-joints, and we found the relationship between welding condition and crack occurrence. Our results demonstrated the probability of narrow groove welding of T-joints between square steel tubes and diaphragms where robot welding was used.