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Ending a weld seam refers to how to extinguish the arc after completing welding with a single electrode. During welding, due to the force exerted by the arc, the molten pool takes on a pit-like shape, and the portion of the weld seam that has already solidified is located below this level. Therefore, if the arc is extinguished immediately at the end of welding, a pit will be formed that is below the surface of the weld seam and even below the surface of the workpiece. In such cases, the ending process for the weld seam requires not only extinguishing the arc but also filling in that pit. There are three common methods for ending a weld bead: I. The circular motion method – when the welding rod reaches the end of the weld bead, circular movements are made using the wrist (without moving the mouth), until the arc pit is filled; then the arc is extinguished. This method is suitable for welding thick plates, but it poses a risk of burn-through when used on thin plates. 2. Repeated arc interruption finishing method: When the electrode is brought to the end of the weld bead, the arc must be extinguished and reignited several times on the arc crater until it is filled. This method is suitable for welding thin sheets. However, alkaline electrodes are not suitable for this method, as pores are likely to form at the arc crater. 3. The back-soldering completion method: Move the welding rod to the end of the weld bead and then stop, but do not extinguish the arc. At this point, adjust the angle of the welding rod appropriately, that is, move it from position 1 to position 2. Once the arc pit is filled, move it to position 3, and then slowly extinguish the arc. This method is commonly used to extinguish arcs with alkaline electrodes.