The Study On Current Distribution Measurement System Of The TIG Welding Arc

In this paper,reviewed various welding arc current density distribution measurement technology, analysed the similarities and differences of them.According to current density distribution measurement of the TIG welding arc on the workpiece surface, designed a set of current gathering system of the TIG welding arc. Using the thought of segment the welding arc to each "pixel" point, a new measuring method is put forward based on a "aequilate line-concentric circles segmentation" model, realized the research of current density distribution of the welding arc on the workpiece surface.According to current density distribution of the TIG welding arc on the workpiece surface, a kind of current sensor is designed to shield the outside strong electromagnetic interference, realizing the gathering of arc voltage signal factually and reliably; A set of walking mechanism to drive the relative motion of the welding arc and current sensing device is built to avoid the welding arc "stuck" phenomenon in the process of movement; Based on the virtual instrument thought, using of high-speed data acquisition card and other hardware facilities, programmed a set of voltage signal acquisition, display, storage program,using the Lab VIEW software; By setting up the current gathering system, carried out a series of early exploration experiment, determined the key parameters of the final gathering experiment, seam width1mm, welding arc length3mm, sampling resistance10Ω, distance between the upper and lower plate less than0.21mm. Analysed and processed the data latterly, acquired16data of current density on the workpiece surface axially, based on a "aequilate line-concentric circles segmentation" model. Finally,realized the3D reconstruction of the welding arc current density distribution on the workpiece surface.In this paper,made a deep exploration of welding arc current density distribution on the workpiece surface,having a profound comprehension of the TIG welding arc characteristics, acquiring the key parameters of the gathering experiment. Eventually,reconstructed current density distribution of the whole welding arc,which provides a certain reference for the scientific research and engineering application of the welding arc.