基于ARM的双丝高效埋弧焊协同控制系统的研究

发布时间：2018-11-20 06:43

【摘要】：与单丝埋弧焊相比,双丝埋弧焊具有两个电弧,输入的总热量增加,能显著提高焊接效率,且在高速焊时能有效避免咬边、驼峰等缺陷。目前,普通双丝埋弧焊的两台电源同时起弧和收弧,起弧和收弧两处只有单丝效果,焊缝宽度较窄,焊接强度难以符合要求,浪费母材;收弧过程中的大电流作用会导致焊缝的尾部形成很大的弧坑,熔化的焊丝不足以填满弧坑,焊缝尾部下塌。另外,后置焊丝采用的交流电源在高速焊接时容易起弧失败或断弧,影响焊接效果。本文提出了通过协同控制系统解决以上问题的方案。焊接启动时,启动行走小车,前置焊丝起弧,当后置焊丝到达前置焊丝起弧的位置时,后置焊丝起弧;焊接结束时,先停止前置焊丝输出,后置焊丝到达前置焊丝收弧的位置时,停止行走小车,逐渐减少后置焊丝的电流和送丝电压。协同控制双丝埋弧焊系统具有完整的双丝焊焊接效果,收弧过程中的弧坑问题也得到明显改善。母材被前置焊丝预热后,后置焊丝起弧和维弧需要的能量减少,使双丝焊焊接更稳定,焊接效果更好。本文以基于ARM Cortex?-M4内核的微处理器TM4C123GHPGE作为主控芯片,开发了双丝高效埋弧焊协同控制系统,设计了相关的硬件电路和软件。硬件电路包括最小系统、带隔离的数模转换电路、AD采样电路、CAN总线通信接口电路、送丝电路、行走小车速度控制电路等。软件包括主程序,参数预置、焊接启动、焊接过程控制、焊接停止、AD采样、CAN通信等子程序。同时,设计了基于ARM和触摸屏的人机交互系统,实现了人机交互系统的数字化和可视化。最后,基于协同控系统搭建了实验平台,进行了单丝直流埋弧焊实验、单丝交流埋弧焊实验、普通双丝埋弧焊实验和协同控制双丝埋弧焊实验。实验结果表明,协同控制双丝焊系统工作可靠稳定,焊接质量好,焊接效率高,焊接过程、起弧和收弧的协同控制效果良好,实现了双丝埋弧焊的协同控制。
[Abstract]:Compared with single wire submerged arc welding, double wire submerged arc welding has two arcs, increases the total heat input, can significantly improve the welding efficiency, and can effectively avoid the defects of cutting edge and hump in high speed welding. At present, the two power sources of common double wire submerged arc welding start and close arc at the same time. There is only single wire effect in arc starting and arc closing, the width of weld is narrow, the welding strength is difficult to meet the requirements, and the base metal is wasted. The large current in the arc closing process will result in the formation of a very large arc pit at the end of the weld, and the welding wire will not be sufficient to fill the arc pit, and the tail of the weld will collapse. In addition, the AC power supply used by the post welding wire is apt to cause arc failure or break arc in high speed welding, which affects the welding effect. In this paper, a scheme to solve the above problems by cooperative control system is put forward. When the welding start, start walking car, the front welding wire start arc, when the rear welding wire reaches the position of the front wire starting arc, the rear welding wire starts the arc; At the end of welding, the output of the front welding wire is stopped first, and when the post wire reaches the position of the arc closing of the front wire, the walking car is stopped, and the current and the wire feeding voltage of the post wire are gradually reduced. Co-control double wire submerged arc welding system has a complete effect of double wire welding, and the arc pit problem in the process of arc closing has been obviously improved. After the base metal is preheated by the front welding wire, the energy needed for the arc starting and the dimension arc of the post welding wire is reduced, which makes the double wire welding more stable and the welding effect is better. In this paper, based on the ARM Cortex?-M4 core microprocessor TM4C123GHPGE as the main control chip, a double wire high efficiency submerged arc welding cooperative control system is developed, and the related hardware circuit and software are designed. The hardware circuit includes minimum system, digital-analog conversion circuit with isolation, AD sampling circuit, CAN bus communication interface circuit, wire feeding circuit, speed control circuit of walking trolley and so on. The software includes main program, parameter preset, welding start, welding process control, welding stop, AD sampling, CAN communication and so on. At the same time, the human-computer interaction system based on ARM and touch screen is designed, and the digitization and visualization of human-computer interaction system are realized. Finally, the experiment platform is built based on the cooperative control system. The experiments of single wire DC submerged arc welding, single wire AC submerged arc welding, common double wire submerged arc welding and cooperative control double wire submerged arc welding are carried out. The experimental results show that the double wire welding system works reliably and stably, the welding quality is good, the welding efficiency is high, the cooperative control effect of welding process, arc starting and arc closing is good, and the cooperative control of double wire submerged arc welding is realized.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG409

【参考文献】