A: Could you introduce this welding equipment to me? B: Sure. The welding equipment is called a wire feeder . A: What are the main parts of it? B: The main parts of it are: handle , wire reel , wire drive-roll, controlling panel, gas passage and current cable. A: Why don’t we use the wire feeder in manual arc welding ? B: A good question. In manual arc welding, the stick-electrode is straight and stiff, and cannot be curled up . So it cannot be fed by the wire feeder. A: So that’s why we have to change the electrodes ourselves. B: That’s true. Once the stick-electrode is used up , you have to stop welding to change a new one. During the whole welding, you have to change new electrodes from time to time. It may be a waste of time. Therefore, the welding efficiency is low. A: Oh, I see. By the way, in what welding processes is a wire feeder used? B: Well, it can be used in automatic or semi-automatic welding processes. For example, it can be used in gas-shielded metal-arc welding (e.g. CO2-shielded welding process), flux-cored arc-welding (self-shielded flux-cored arc-welding, gas-shielded flux-cored arc-welding), submerged-arc welding and robot welding . In these welding processes, we don’t need to change new wires ourselves. The wire feeder can do the job for us. It can feed the wires automatically and continuously . A: Really? It sounds so good. So we can save the time of changing new wires. B: So the welding efficiency is greatly increased . A: By the way, what kinds of wires can a wire feeder feed? B: It can feed solid wire and flux-cored wire, because they can be curled up. But it cannot feed stick (covered) electrodes, because they cannot be curled up. A: Now, I know a lot about wire feeder. Thank you so much. B: My pleasure.