Strainers are components to separate or eliminate foreign objects or contaminants in the liquids/gases flowing inside the piping. A built-in mesh net called screen serves as a filter. This net is removable and can be replaced easily with a new one when it gets dirty. Strainers have various structures and shapes according to the installation location and the application. The most common type, Y strainers, have large filtration areas and are mainly used for pipelines of automatic valves. Other strainer types include U strainers mainly for liquids, and T strainers featuring excellent maintainability, workability and reduced pressure loss that were problems of conventional strainers. Foreign objects or contaminants in the pipelines may damage each pipeline and valve. Strainers are an important component to prevent those damages.