Fluid density valve, method, and system

Abstract

A fluid density valve housing includes a pilot fluid inlet and outlet and a primary fluid inlet and outlet. A shuttle is disposed within the housing. The shuttle comprises a portion having a reference density and a portion defining a cavity fluidically connected to the pilot fluid inlet, the shuttle permitting or denying primary fluid flow depending upon a density of a pilot fluid flowing through the cavity versus the reference density. A method for controlling flow, including comparing density of a pilot flow with a reference density, moving a valve between fully open, fully closed, and choked depending upon the differential density between the pilot fluid and the reference density. A borehole system, including a borehole in a subsurface formation, a string in the borehole, and a fluid density valve disposed within or as a part of the string.

Dependencies are inferred from the claim text.