Definition - What does Standing Valve mean?
A Standing Valve is the valve which helps the flow of fluids from the bottom of the wellbore, as well this valve holds the pressure from above. It is a fixed position valve that is used when the fluid is to be maintained in the tubing string. There are several other applications of the Standing Valve such as tube string testing and setting packers.
Petropedia explains Standing Valve
The standing valve comes with the spring loaded relief valve. These spring loaded relief valve helps in pushing out the fluids from the end of the tubing. These spring loaded relief valves are positioned below the seat and the ball. Other than the well completions, a Standing Valve is also used in the production testing where it is used to block the downward flow of the fluid and permit the flow to fill the pump barrel chamber.