The strainer’s initial cost is good insurance against the cost of down time and replacement parts incurred from a damaged flow meter.
A meter strainer installed on the inlet side is necessary even when a coarse strainer on the upstream side of the pump is included in the system. Strainers are not meant to be used as a system filter but as limited protection for the flow meter element itself.
As a liquid product enters the strainer housing from the supply line, it is routed through the strainer basket. The strainer basket is a two-ply screen. The inner screen is made of fine mesh of either 20, 40, 80, 100, or 200 squares per inch. The outer screen works as a backing. It gives reinforcement and support to the fine mesh inner screen. Liquid passes through the strainer and into the inlet of the meter. Any debris that is larger than the mesh in the basket is trapped in the basket.
THE STRAINER IS NOT A FILTER, and the size of the mesh in the basket selected will determine the particle size that can pass through the strainer. Basket mesh selection is generally based on maximum fluid viscosity at minimum ambient operating temperature.