Final answer:
Preventing arc blow is addressed in welding subject matter, and it involves controlling magnetic disturbances during welding. Techniques include using DC or AC welding machines, managing alignment, and maintaining proper grounding to minimize or prevent arc blow.
Step-by-step explanation:
Preventing arc blow is typically covered in a welding or engineering courses under the topic of best practices and troubleshooting in welding processes. Arc blow is a welding defect caused by magnetic disturbances during the welding process, which can result in welds that are not consistent. To prevent arc blow, welders need to control factors such as the alignment of workpieces, the magnetic field around the work area, and the welding technique itself.
For example, using direct current (DC) welding machines with the electrode negative (straight polarity) or alternating current (AC) can help minimize arc blow. Additionally, tack welding or using guide jigs to maintain the alignment can be effective. Keeping cables straight and as short as possible, and sometimes even demagnetizing the workpieces before welding, are other techniques used to prevent arc blow. Properly grounding the work piece and maintaining a consistent travel speed and angle can also make a significant difference in preventing arc blow.