Development Of A New Type Of Composite Wire TIG Welding Device

TIG welding using inert gas protection, arc burning is quite stable, the weld line is excellent, high-end industrial sector welding welding process parts and precision parts preferred. But because of limited capacity of load flow TIG welding electrode, the arc power is limited, the deposition rate is low, especially the welding structure of medium thickness, need to open and multi-layer welding groove. With the welding efficiency and automation requirements, hot wire TIG welding for its excellent characteristics, by the majority of domestic and foreign welding concern. At present, hot wire TIG welding power source is composed of welding power source and wire power supply, and the two are independent of each other.This paper is based on comprehensive at home and abroad on the hot wire TIG welding power source on the research and development, a dsPIC30F6011, dsPIC30F2020 and PIC18F4580 as the core control chip based on new welding equipment all digital AC pulse design. The main circuit of welding power supply AC output by two inverter, an inverter with IGBT full bridge topology, two inverter using IGBT push-pull topology.This will be through the design of the overall framework, the corresponding analysis on the main circuit topology of welding power source, and the electronic components are selected. Through the control circuit of the hardware and software design, to achieve the full digital control of welding power source, including a two inverter control, inverter control, drive circuit, feedback circuit design, over-current protection circuit design, design, human-computer interaction system of wire feeding system design and the design of digital PID control. At the completion of the main circuit, control circuit and software design under the premise, the first inverter, two inverter, RCD absorption, network characteristics, welding power supply wire feeding system and other aspects of the relevant parameter optimization.Some experiments were done,determined the best operating frequency of the AC power supply wire,get the matching relationship of the wire feeding speed and the hot wire current. When the AC pulse supply current is 100 A, the wire feeding speed can meet the design requirement when 2.3~5.4m/min; When the AC pulse supply current is 150 A, the wire feeding speed can meet the design requirement when 5.4~8.8m/min;...