Liquid Controls Check Valves are designed to maintain back pressure to increase air/vapor eliminator efficiency and to prevent reverse flow of product through the meter. This assures that the meter and all components downstream remain full of the liquid being measured.
Check Valves are normally closed, spring loaded valves. When fluid enters the meter from the inlet side, and the pressure is greater than the back pressure combined with the force of the spring, the spring will compress, opening the valve thus allowing fluid to pass through (as shown in the figure below).
When back pressure plus spring strength is greater than the fluid pressure entering the meter, the valve will remain closed.
There are six Check Valve models available and the valve model is specified based on the Liquid Controls meter model and accessories being used.
There are many different models:
•Model 41370: Used with M-15, 3” flowmeters.
•Model 41380: Used with M-30, 4” flowmeters.
•Model 502020: Used with M-7 & M-10, 2” flowmeters.
•Model 46743: Used with M-5, 1½” flowmeters.
•Model 49896: Used with M-15 & M-25, 3” flowmeters equipped with a 3”, high capacity strainer.
•Model 501267: Used with MA-4 dispenser flowmeters.
