| 摘要 |
PURPOSE: To detect abnormality as to whether molten pool is larger/smaller than normal state at welding and other abnormality of misalignment, center deviation, etc. CONSTITUTION: A molten pool 6 of welding part and its neighborhood are image- picked up and displayed on a monitoring screen 10. On the monitoring screen 10 in a range of the contour 6a of normal molten pool 6, a first detecting part 12 to detect the molten pool 6 is arranged, a second detecting part 13 to detect molten pool 6 outside the contour 6a of normal molten pool along advancing direction of welding, at the position corresponding to the end part of the molten pool 6 on welding base metals 1A, 1B, a pair of third detecting parts 15a, 15b detectable a welding arc light and weld line 2 are arranged across the weld line. |
