某电厂圆形零件机器人智能焊接

Robot intelligent welding for round parts in a power plant

采用机器人焊接某电厂圆形零件,制作焊接工艺评定规程,采用有限元分析方法优选焊道排布方案,在工件坐标系内建立每条焊道的起弧点坐标。使用机器人激光视觉对工件特征点进行抓取,结合三点定圆心算法拟合工件坐标系和机器人坐标系,从而对机器人工作台范围内任意放置的零件自动定圆心。根据大量熔敷成形试验,对每条焊道起弧点位置进行修正,并在拟合后坐标系内将修正后的起弧点坐标、优选的焊道排布方案编辑成机器人焊接路径程序,结合焊机内存储的焊接工艺程序,对在机器人工作台范围内零件智能定位,机器人自动行走并调用焊接工艺,实现智能焊接。最后对该圆形零件进行无损及理化检验,结果合格。

The robot was used to weld round parts of a power plant and make welding procedure qualification. Finite element analysis method was adopted to optimize layout of weld pass and starting arc coordinates of each weld pass were established in coordinate system of workpiece. Feature points of workpiece were captured by laser vision of robot, and coordinate systems of workpiece and robot were fitted with three-point centering algorithm, so that parts placed arbitrarily in the range of robot workbench could be centered automatically. According to a large number of cladding forming tests, starting arc position of each weld pass was corrected, and the corrected starting arc coordinates and the optimized layout of weld pass were edited into robot welding path program in the fitted coordinate system. Combined with welding process program stored in the welder, parts in the range of machine’s workbench were intelligently positioned, and the robot could automatically walk and invoke welding process to realize intelligent welding. Finally, circular parts were tested by non-destructive inspection and physical and chemical inspection, and the results were qualified.