STRAINER can be defined as a pipe fitting through which liquid is passed for purification, filtering or separation from solid matter; anything used to strain a liquid; any device functioning as a sieve or filter used to prevent solid bodies from mixing in a liquid stream or flowline.
STRAINERS arrest pipeline debris such as scale, rust, jointing compound and weld metal in pipelines, protecting equipment and processes from their harmful effects, thus reducing downtime and maintenance. Use of rightly selected strainers at correct locations (usually upstream) is a must to protect expensive and critical downstream equipment such as pumps, flow meters, steam traps, control valves etc