STANDING VALVE ASSEMBLY
This small but important sub-assembly is basically a non-return valve or check valve; however, it is specially designed for jet pump applications. The standing valve is typically located at the bottom section of the BHA, and it is landed inside the BHA at its no-go ring.
The standing valve has two important tasks:
To keep the fluids contained in the tubing and annulus in place when the jet pump system is shut down. When power fluid injection stops, the check valve ball falls on top of the seat providing a metal-to-metal seal that holds any fluid column above it. If it weren't for the standing valve, all fluids contained above the packer would flow down into the formation.
It enables us to retrieve the jet pump hydraulically up the surface. The "free style" jet pump can be hydraulically reversed to the surface into the Christmas tree by injecting power fluid down the casing. The standing valve closes, and redirects the fluid pumped down the casing up the tubing, so the jet pump is hydraulically lifted up to the surface.
