초록 ▼

A downhole valve 10 opens or closes a bypass (12,13) in response to the pressure of the fluid in the valve. The valve housing body 14 is adapted for fluid communication with a tubular within a well bore. The valve bypass may be repeatedly cycled from open to closed position by selectively raising an

A downhole valve 10 opens or closes a bypass (12,13) in response to the pressure of the fluid in the valve. The valve housing body 14 is adapted for fluid communication with a tubular within a well bore. The valve bypass may be repeatedly cycled from open to closed position by selectively raising and lowering the fluid pressure. A replaceable flow restriction 18 in the valve is sized to produce a desired flow-induced pressure drop across the valve to cycle the valve with fluid flow. Differential sealing areas (11c and 15,16) are provided to cycle the valve by varying the static fluid pressure in the valve. According to the method, a flowing fluid pressure drop induced by fluid flow through the valve is used to change the state of the valve, and a subsequent change in hydrostatic fluid pressure or fluid pressure is used to return the valve to its original state.

대표청구항 ▼

A method of operating a downhole subsurface valve from a remote surface location, the subsurface valve positioned in a wellbore along a tubular string, comprising: initiating fluid flow through the tubular string and to said valve adequate to shift a flow responsive bypass valve closure mechanism in

A method of operating a downhole subsurface valve from a remote surface location, the subsurface valve positioned in a wellbore along a tubular string, comprising: initiating fluid flow through the tubular string and to said valve adequate to shift a flow responsive bypass valve closure mechanism in the valve from a first open position to a second open position; reducing the pressure of the fluid in the tubular string and to the valve to mechanically shift the bypass valve closure mechanism to a third open position; increasing the pressure of the fluid in the tubular string and to the valve to shift the bypass valve closure mechanism from said third open position to a first closed position; and lowering the pressure of the fluid in the tubular string and to the valve to allow the valve closure mechanism to shift the bypass to a mechanically retained second closed position.