| With the popularity of high power laser, laser-arc hybrid welding is more often used for welding thick plates in industry. Since there are many parameters, during the welding process, if we choose the improper parameters or there is assembly error, the welding process will be unstable and there may be weld quality issues such as surface depression and weld misalignment. Therefore, developing a quality monitoring system for laser-arc hybrid welding is very valuable.For this reason, we develop a quality monitoring system for laser-arc hybrid welding. The system is based on the collect and analyze of melt pool image and welding current and voltage. We use an industrial camera and Hall sensors as the hardware, and take LabVIEW as the programming software. And we achieve to monitor the image of hybrid welding pool and the welding current and voltage. By analyzing the connection of weld quality issues and the change of parameters, we achieve the automatic judgement of several typical weld quality issues.The quality monitoring software system contains basic information storing module, real-time data collecting module, historical data reviewing module, form reporting module and helping module. By using the software system, we can storage information like operation staff, operation data and technical parameters, capture images of meltpool and measure the width of the welding pool, collect and analyze welding current and voltage, judge weld quality issues and make warning, review historical data and report forms.The quality monitoring system can judge the unsteadiness of welding process by analyzing the variance of welding voltage, and judge the weld misalignment by analyzing the change of the width of welding pool. While the welding process is unstable, the variance of welding voltage will be 2.5 times as the average value. The system can judge the surface depression by analyzing the decrease of the width of welding pool. While there appears surface depression, the width of welding pool will reduce 25% of the average value. The system can judge the weld misalignment by analyzing the increase of the width of welding pool. While there appears weld misalignment, the width of welding pool will increase 23% of the average value.At last, we verify the feasibility and reliability of the system by welding 6mm thick low carbon steel plate. |
