DOWNHOLE FLOW CONTROL DEVICE

摘要

A downhole flow control device (30) comprises a housing (70) to be secured within a wall of a tubular and comprising an inlet port (82), an outlet port (76) and a valve seat surface (97) surrounding the inlet port. A valve plate (72) is mounted within the housing to move between an open position in which the valve plate is separated from the valve seat surface to define a separation flow path therebetween to permit flow in a forward direction from the fluid inlet to the fluid outlet, and a closed position in which the valve plate is engaged with the valve seat surface to close the separation flow path to restrict flow in a reverse direction from the fluid outlet to the fluid inlet. At least one of the valve seat and valve plate defines a geometry to encourage an increase in static pressure of fluid flow in the separation flow path when said valve plate is in its open position.