焊接现场脉冲GTAW熔池图像动态检测

Dynamic monitoring of weld pool image for pulsed GTAW in welding scene

关键词:  熔池  视觉检测  脉冲钨极氩弧焊  焊接现场  光谱分析

Key words:  weld pool  visual monitoring  pulsed gas tungsten arc welding  welding scene  spectral analysis

摘要:

通过熔池的动态观测可以获得焊接过程的稳定性和连续性等信息。熔池的动态观测目前基本上停留在试验室阶段,焊接现场对熔池进行观测在改进工艺和指导生产等方面更具意义。针对焊接现场焊接电源不能修改,非计算机可控,电流电压波形未知等问题,在焊接现场建立了一套焊接熔池图像动态检测系统。根据焊接现场脉冲GTAW的特点,采用"外同步取像"方式确定了焊接现场取像的关键制约因素——取像时刻;并利用电弧光谱分析建立了减小弧光干扰的复合滤光系统;在适合的取像时刻,CCD摄像系统配合复合滤光系统,在焊接现场检测到了清晰的熔池图像。

Abstract:

Information on stability and continuity of welding process can be obtained by dynamic monitoring of weld pool.The dynamic monitoring of weld pool is still in laboratory stage.To monitor weld pool in the welding scene is more valuable in both welding process improvement and production guide.However, there are some problems in welding scene, for example, the welding power sources cannot be modified and incontrollable by personal computer; the waveforms of welding current and voltage are unknown and so on.For these problems, a weld pool image dynamic monitoring system was setup in the welding scene.According to the characteristics of pulsed GTAW (gas tungsten arc welding) in the welding scene, the time to take image, which is the most important factor to restrict to take image in the welding scene, is determined by external synchronization; using the spectral analysis, a compound filter system, which reduces the interference of arc, was proposed;at the optimum image taking hour, clear images of weld pool were obtained by CCD with the compound filter system in the welding scene.