The study discusses remote control torch system that is equipped with CO2 double wire reel. The welding machine is 30m away from the wire feeder at the industrial site and the feeder is three to five meters away from the torch. Accordingly, the welders cannot control the current and voltage that meets the welding condition during work when they are working at a place that prevents them from seeing the control panel such as inside a vehicle or tank or at a far work site. They also have no choice but to stop working to change the wire reel when it is completely burned out. Such work suspension resulting from frequent moves to adjust current and voltage as well as replace the wire and subsequent cooling causes welding defects. The study produced a remote control torch equipped with double wire reel by simplifying and streamlining the existing CO2 functions to reduce the troubling issue. The remote control torch equipped with double wire reel and the existing CO2 /MAG welding torch were applied as V-groove butt in the vertical position using 9mm rolled steel for SM50A welding structure. After completion of welding, the condition of welded surface beads went through visual inspection as well as radiographic inspection to analyze the welding quality inside the welded part. The study also evaluated reduction of welding defects, cost saving, the replacing performance against the existing commercial welders and the effect on possible compatibility

The purpose of this study is to determine more variables in welding characteristics of ATOS(steel for automobile structure) 80 high tensile steel available in market, and in terms of welding using GMAW(gas metal arc welding), this study seeks to examine how welding characteristics of ATOS 80 may vary depending on protrusion length of wire electrode. The major characteristics of this study can be summed up as follows, this study analyzed welding characteristics of ATOS 80 by changing the protrusion length of wire electrode (10㎜, 15㎜ and 20㎜) in welding section, and also used visual inspection and radiograph test to examine observations of major defects on welding section.