플라즈마토치 용융로에 있어서 내화물의 보수를 최소화하고 용융물의 배출을 원활하게 하기 위해서는 처리대상 폐기물의 물 성을 충분히 고려하여야 한다. 원전에서 발생되는 비가연성 방사성폐기물 중 많은 비중을 차지하고 있는 콘크리트 조각, 유 리, 모래 등에 대한 화학적 조성비를 조사하여 보면 산성산화물이 염기성산화물에 비해 압도적으로 많은 비중을 차지하고 있 으므로 용융 시 염기도가 매우 낮은 산성 슬래그가 된다. 이 용융슬래그는 유동도가 낮아서 용융물의 배출특성이 좋지 않으 며 내화물에 침식을 유발시키는 주된 요인이 된다. 경사형 구조의 측면 출탕구를 가진 플라즈마토치 용융로의 경우, 구조상 출탕 후 일정량의 금속성 용융물이 항상 용융로 내부 바닥과 출탕구에 남게 된다. 비중차에 의해 비금속 용융슬래그는 금속 성 용융물 상부에 위치하게 되며 혼합형 플라즈마토치를 이행형 운전모드로 가동하게 되면 금속성 용융물과 비금속 용융물 이 동시에 용융되므로 비금속 용융슬래그의 온도는 금속 용융온도 이상으로 유지가 된다. 내화물의 수명 향상을 위해 용융로 내부의 온도와 용융물과 접촉하는 부위와 접촉되지 않는 부위를 구별하여 내화물의 특성을 주지하고 가장 적합한 내화물을 부위별로 선정하였다. 산성 내화물과 염기성 내화물이 인접하지 않도록 하고 용융슬래그에 대한 저항성을 높이도록 하였다.

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

In GMAW welding used mostly at the scene of a welding industry, welders can not see control panels in internal welds of vehicles and tanks, and can not adjust the current and voltage properly during the welding, which is caused by distance from the working area. Therefore, welders have to move to control the current and voltage by stopping welding. This, however, can result in the welding defects by momentary cooling. In this research related to the existing GMAW welding methods and the manners with the remote control torch their performances were evaluated by comparing and analyzing the welds of V-type butt using SM50A 6 mm and welding structural rolled steels. As the result of conducting the visual inspection and bending test one by one against the V-type butt welds, the amount of spatter by the remote control torch method showed reducing effects about five times lower and it had a performance that did not affect the weld defects by displaying suitable effects on the bending test of welds. Consequently, the experimental study on the possibility of replacement and compatibility with the existing commercial welder for the remote control torch was performed.

This paper considers a problem of optimizing torch paths to cut stock plates nested with open contours. For each contour, one of the two ending points is to be selected as a starting point of cutting with the other being the exit point. A torch path is co