MIG Welding Arc Spectrum Diagnosis Under Pressure

The gas protection welding characteristics is quite different between atmospheric pressure and under pressure environment.The research about GMAW Hyperbaric welding is of important guiding significance for underwater GMAW Hyperbaric welding.Based on the principle of plasma arc spectrum diagnosis, test platform and MIG welding spectrum diagnosis System are designed for GMAW Hyperbaric welding experiment. The Portable Spectrometer is used in this experiment,which collects informention throuth Fiber probe.The information is transmited out of the high pressure vessels by electric cable which pass through the high pressure vessels. The main work and conclusions are as follows:The paper has analyzed the MIG spectrum information. After much calculation, three characteristic lines were selected. two other lines which had larger deviations also were chosen as reference spectrum.The paper has analyzed different arc position temperature, mainly for axial position and radial position,and got the arc temperature distribution within the arc space.Variation of arc temperature under different pressure was studied. Comparied of arc temperature under normal pressure, MIG arc temperature increased with the pressure.The paper has carried out the current experiment. Comparied the temperature under atmospheric conditions and under pressure conditions,and got the variation of the arc temperature under different current.During the experiment, the method of average value was used for reducing error caused by welding instability. The influence law of pressure and current on the arc temperature has guidance for the actual welding process.