A strainer is a device that is used to remove unwanted solid particles, debris, or foreign matter from a fluid or gas stream. It is typically installed in pipelines and other fluid handling systems to prevent clogging or damage to downstream equipment. Strainers are available in various sizes and configurations, including Y-strainers, basket strainers, and duplex strainers. Depending on the application, strainers can be made of materials such as stainless steel, brass, or plastic. They are commonly used in industries such as chemical processing, oil and gas, and water treatment.