method for controlling flow between an internal flow passage of a tubular column and an external annular to the turbular column in an underground well and valve for use in an underground well

摘要

Method for controlling flow between an internal flow passage of a tubular column and an external annular to the tubular column in an underground well and valve for use in an underground well A method for controlling flow between an flow passage of a tubular column and an annular includes: constructing a valve having an opening for flow between the passageway and the annular; allow flow through the opening; then prevent flow through the opening in response to pressure applied to the valve; and then mechanically displacing a closure device thereby allowing flow through the opening. another method includes applying a pressure differential across a valve piston thereby displacing a closure device; and then displacing the closure with respect to the piston, thereby allowing flow between the passage and the annular. a valve includes an opening for flow between an interior and an exterior of the valve, a closing device for allowing and preventing flow through the opening, and a piston that deflects the closing device for displacement, the closing device being mechanically displaceable with respect to the valve. piston.