Weld joint deviation identification method, based on waveform matching, of rotating arc narrow gap gas shield welding

Abstract

The invention discloses a weld joint deviation identification method, based on waveform matching, of rotating arc narrow gap gas shield welding. The method comprises the steps of firstly creating waveform function templates of welding eclectic signals or relevant parameters corresponding to different weld joint deviations in a simulation modeling mode or an experimental modeling mode, then adopting an arc electric signal sensor, an arc position sensor, a data acquisition card and the like to collect welding experimental data in an on-line predication mode, extracting arc electric signals during each arc rotating period through a data preprocessing module, matching the arc electric signals with the waveform function templates under different weld deviations obtained during modeling, selecting the weld joint deviation corresponding the most matched template as the welding joint deviation during the current arc rotating period, synthetically considering history values of a plurality of arc rotating periods, so as to overcome the influence of accidental factors, and counting for output. By adopting the method, the capacity of resisting disturbance of the arc sensor can be further improved, and simultaneously overall features of welding current sampled signals are fully considered, so that the deviation extraction result is more reliable.

Description

technical field [0001] The invention belongs to the technical field of welding automatic control, and relates to a weld seam deviation identification method, and more particularly relates to a waveform matching-based rotating arc narrow-gap gas shielded welding weld seam deviation identification method. Background technique [0002] As an efficient welding technology, rotating arc narrow gap gas shielded welding is widely used in the field of medium and thick plate welding. In order to ensure the welding quality and avoid defects such as unfused side walls, it is necessary to ensure that the arc is in the center of the groove during the welding process. Position, that is, real-time and effective tracking control is required, and the key is to be able to reliably extract weld seam deviations in real time. [0003] At present, the online real-time sensing device based on the weld deviation identification method commonly used sensors include mechanical sensors, electromagnetic ...

AI Technical Summary

Problems solved by technology

[0005] During high-speed rotating arc gas shielded welding, the molten metal is restrained by the side wall. At the same time, due to the high deposition rate of the welding wire, the liquid metal in the molten pool is thicker and the liquid level is larger. The arc shape has a special change rule, which makes The application effect of the existing arc sensing method needs to be re-verified, and there are a lot of uncertain factors in the welding process, such as the accumulation of molten iron at the back end of the molten pool, the stirring effect of the arc on the molten pool, low groove processing accuracy, assembly errors, Misalignment caused by workpiece assembly or thermal deformation, etc., puts forward new requirements for effective tracking and accurate identification of weld deviations, so it is urgent to improve the existing identification methods

There is a patent with the application number 200910025826.2. The content of the invention is to use the sampling results of the welding current signal combined with the idea of ​​function approximation to calculate the deviation information of the welding torch position, which is mainly for the swing arc and does not involve the rotating arc.

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