Weld Quality Monitor and Control System
A non-contact Weld Quality Monitor (WQM) system is being developed to detect, identify, and correct for deviations from established welding procedures and conditions which lead to weld defects in real time. The WQM continually measures with conventional transducers all primary process parameters such as current, voltage, and travel speed, and computes weld quality parameters such as heat input and weld bead geometry. In addition, the WQM monitors the spectral signature of the welding arc by means of a high resolution microprocessor controlled spectrograph. Here, the presence of weld pool and arc atmosphere contaminants, flux and shield gas effectiveness, arc energy input, and penetration/dilution into the base material can be determined. The spectral response from the welding arc and measurements of process parameters are then normalized, compared to. preset operating limits, and processed in real time. Necessary adjustments to primary process parameters will be made by automated compensation devices to eliminate weld defects in real time. When necessary, the specific location of discontinuities will be provided to facilitate further inspection.
KeywordsWeld Pool Travel Speed Weld Defect Process Data System Wire Feed Speed
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