| 摘要 |
PURPOSE:To prevent burn-through by mounting dry ice on the back and cooling sheets in the case of performing lap welding of the sheets. CONSTITUTION:One end part of a pipe 1 of a plate thickness 1mm composed of Ni alloy steel is rolled and coiled with a ring 2 of a plate thickness 1mm likewise composed of alloy steel and the mating faces are TIG-welded 4 to bond 1 and 2. At this time, dry ice 3 is mounted on the inside surface of the pipe to let the heat evolved during welding be effectively absorbed, whereby good welding free from burn-through is accomplished. |
