| 摘要 |
<p>In the termination of an arc welding operation using a protective gas and driect current (D. C) from a source fitted with stepping switches, the consumable electrode feed is obtd by a motor (1). A second motor (2) produces relative motion between the arc and the workpiece. When the end of the seam is reached, an end signal, pref. obtd. from a limit switch, stops motor (2). Specifically, the end signal also reduces the welding voltage and the electrode feed to defined values for a specific transition time and finally cuts off the welding current and stops the electrode feed. Prevents the formation of a crater at the end of a welded seam which melts the workpiece and produces a zone which is mechanically weak.</p> |
