The Research Of Welding Arc Physical Characteristic In Hyperbaric TIG Welding

The effect of environmental pressure on hyperbaric TIG welding arc cannot be neglected. And the research of the arc behavior in high pressure environment is critical to understand the property of the hyperbaric welding process, to develop corresponding welding material and to acquire favourable welding connecting.Based on the in-depth investigation of the principle and the latest progress of plasma spectrum diagnosis, a set of feasible high-pressure arc spectrum diagnosis device have been established. The collection of welding arc signal, spectral analysis and several kinds of calculating method are investigated in details. As to research welding arc under high-pressure, the portable Spectrometer is used in this experiment. Through the optical fiber, the arc light signal is collected. The three-dimension electric motion transfer is adopted to control the optical fiber probe. The electrical signal of the spectrometer is drawn out from the hyperbaric chamber by the data transmission lines. The welding arc spectrum is gathered and preserved by the computer using spectral analysis software.Through the analysis of TIG arc spectrum in the high-pressure environment, the argon spectral emission lines is used as the analyzing arc spectrum. Four couples of ArI lines for arc temperature analysis and two piece of ArI lines for electron density analysis are determined through selection of the ArI emission lines.According to the actual characteristic of the TIG welding arc, the spectrum Stark broadening is used to analyze electron density and the dual linear spectrum is used to analyze arc temperature.The system analysis of arc temperature and electron density in different environment pressure and electron density in different current is made. Their own law of changes is finded.According to the analysis, the relational curve of the electron and the environment pressure has been established, it has universal significance to the variation of electron density in high-pressure environment. The analysis of welding arc behavior has been made, it has instructional significance to the actual welding process.