What tool is typically used for tightening or loosening threaded connections in plumbing?

The pipe wrench is a specialized tool designed to grip and turn round objects, primarily employed for tightening or loosening threaded connections in plumbing systems. Its unique design features serrated jaws that provide a strong grip on pipes, preventing slip while exerting the necessary torque. The adjustable nature of the pipe wrench allows it to accommodate various pipe sizes, making it indispensable for tasks such as connecting or disconnecting fixtures, valves, and pipes.

While other tools like pliers can also be used to grip and turn pipes, they may not provide the level of torque or grip that a pipe wrench can, especially on larger fittings. A screwdriver, in contrast, is intended for driving screws and cannot adequately address the needs of plumbing connections. Similarly, a hacksaw is meant for cutting through materials rather than manipulating or securing threaded connections. Therefore, the pipe wrench stands out as the most appropriate tool for this function in plumbing work.