Automatic real-time bead height control with arc sensor in TIG welding.

Arc sensor, which utilizes the welding arc as a sensor, gives important groove information during welding. Automatic seam tracking control system with arc sensor developed by NKK has a fesature, that a turning point of transverse weaving with constant arc length control (AVC) is decided by the condition, when torch height reaches to constant set level. Under applying above control system, variation of groove and deposition area can be detected from the trace of weaving. The automatic real-time bead height control system has been developed utilizing above detected information. The area and width of weaving trace has close corelation with the area of groove and deposition. Experiments conducted with varied groove width proved satisfactory control ability for all position TIG welding.