Pressure controlled reversing valve
Modulating flow control valve assembly
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Methods and apparatus for selectively controlling fluid communication between a pipe string and a well bore annulus
Automatic valve for use with pool cleaning devices
Method and device for adjusting the path of a drilling tool fixed to the end of a set of rods Patent #: 4848488
ApplicationNo. 535846 filed on 09/28/1995
US Classes:137/10, By speed of fluid137/12, By fluid pressure137/115.09, Choke137/115.24, Mechanical movement between sensor and valve137/624.14, Self-cycling166/317, Destructible element166/319, Fluid operated166/332.1Longitudinally movable operator
ExaminersPrimary: Hepperle, Stephen M.
Attorney, Agent or Firm
Foreign Patent References
International ClassE21B 034/10
AbstractA 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.