Abstract
Shop-welding robots have been already lined as main production tools in the automobile industry. And recently the employment of welding robots is increasing in the small factories of the steel fabricators. But the development of field-welding robots is very much behind that of shop-welding robots, because being a precision machine, field-welding robots must be employed in disarranged circumstance of the building site, and column-to-column welding joints are full penetration single bevel grooves and require a high level of welding techniques together with many new knowledge in robotic welding. For example, when a pair of robots runs symmetrically on the same rail for welding facing sides of a column to minimize welding shrinkage, a difference of welding shrinkage occurs between preceding and following welding. This paper describes the best conditions of groove shape to get satisfactory welding quality based on a series of experiment on welding shrinkage and opening under backing plate.
