What are the two types of torches commonly used in welding?

The correct choice identifies the two primary cooling methods for welding torches: air-cooled and water-cooled. In welding applications, particularly in processes like GTAW (Gas Tungsten Arc Welding), the torch generates significant heat. To manage this heat and maintain optimal performance, it is essential to have an efficient cooling mechanism.

Air-cooled torches utilize ambient air to dissipate heat, which makes them suitable for lighter-duty applications or situations where mobility is essential. They are typically less complex and easier to handle. Conversely, water-cooled torches are designed for more demanding tasks that generate higher heat, often in thicker materials or prolonged welds. These torches circulate water through channels in the torch body to effectively absorb and carry away excess heat, allowing for a consistent welding arc without the risk of overheating.

The other options do not accurately reflect the cooling methods used in welding torches. Electric and gas-powered relate more to the power source for welding equipment rather than the torches themselves. Similarly, the terms heavy-duty and portable pertain more to the physical characteristics of the equipment rather than their cooling type.