A Y-strainer is a mechanical device used in piping systems to remove solid particles (such as dirt, debris, rust, or scale) from liquids, gases, or steam. It is named for its Y-shaped body, which houses a straining element (usually a mesh or perforated screen) to capture contaminants while allowing the fluid to pass through. Y-strainers are commonly used to protect equipment like pumps, valves, and meters from damage caused by particulate matter.