SUBMERGED ARC WELDING DEVICE

摘要

PURPOSE:To provide a titled submerged arc welding device which eliminates thoroughly the welding defect owing to arc breakage in submerged arc welding in which an output is controlled by a semiconductor element by operating immediately a high frequency generating circuit after detection of the arc breakage to refire the arc in an extremely short time. CONSTITUTION:The electricity of a power source 11 is transformed by a voltage transformer 12, and is made into DC by a thyristor rectifier circuit 13. A welding object 16 is subjected to DC submerged arc welding by means of a wire 15. When the arcing is broken, an ignition control circuit 17 operates to refire the arc but if the time until the refiring is long, a welding defect arises. The voltage of the circuit is detected with a voltage divider 181 and a voltage drop is detected with a current detecting resistor 182. A central processing unit 20 knows the abnormality by the signals from A/D conversion circuits 191, 192. A bi-directional thyristor 23 is immediately actuated to conduct high frequency current to a coil 29 so that the arc is refired in the weld zone by the high frequency generated by a chock coil 14. The time till the refiring is extremely short and the welding defect owing to arc breakage is thoroughly eliminated.