Means for flow controlling hydraulic check valve

Claim 2

A flow controlling valve for use in controlling the flow of fluids from a subsurface formation through a string of tubing which comprises: a tubular section inserted within said tubing string; a sleeve within said tubular section and slideable between an upper and a lower position in said tubular section; a valve in the lower part of said tubular section which is biased toward a closed position and held open by said sleeve when said sleeve is in its lower position; flow restricting means in said sleeve; means biasing said sleeve in an upward direction; hydraulic control means for applying a downward force on said sleeve, said force including means at the surface for controlling the magnitude of said force.

Claim 3

An apparatus as defined in claim 1 in which said flow restricting means is an orifice means held to the inner wall of said sleeve by wireline releaseable latching means.

Claim 4

A flow controlling valve for use in controlling the flow of fluids from a subsurface formation thRough a string of tubing which comprises: a. a tubular section having an elongated recess therein providing an upper downward facing shoulder and a lower upward facing shoulder; b. a chamber in the lower end of said tubular section below said recess; c. a sleeve slideable within said tubular section between an upper position and a lower position; d. a valve seat in the upper part of the said chamber in said tubular section; e. a flapper-type valve in said chamber biased toward a closed position, said chamber and said valve being sized such that said sleeve can extend through the chamber portion of said tubular section, thus holding said valve open; f. an upper facing exterior annular shoulder fixed to and near the upper end of said sleeve; g. sealing means between said sleeve and the interior of said tubular section to form a power fluid cylinder to cooperate with said exterior annular shoulder; h. conduit means connecting said power fluid cylinder to the surface; i. flow restricting means releaseably latched to the interior of said sleeve; j. an annular exterior shoulder fixed to and near the upper end of said shoulder; k. a spring in the said recess of said tubular section and positioned against the annular shoulder of element (j) urging said sleeve in an upward direction.

Claim 5

A flow controlling valve for use in controlling the flow of fluids from a subsurface formation thRough a string of tubing which comprises: a. a tubular section having an elongated recess therein providing an upper downward facing shoulder and a lower upward facing shoulder; b. a chamber in the lower end of said tubular section below said recess; c. a sleeve slideable within said tubular section between an upper position and a lower position; d. a valve seat in the upper part of the said chamber in said tubular section; e. a flapper-type valve in said chamber biased toward a closed position, said chamber and said valve being sized such that said sleeve can extend through the chamber portion of said tubular section, thus holding said valve open; f. an upper facing exterior annular shoulder fixed to and near the upper end of said sleeve; g. sealing means between said sleeve and the interior of said tubular section to form a power fluid cylinder to cooperate with said exterior annular shoulder; h. conduit means connecting said power fluid cylinder to the surface; i. flow restricting means releaseably latched to the interior of said sleeve; j. an annular exterior shoulder fixed to and near the upper end of said shoulder; k. a spring in the said recess of said tubular section and positioned against the annular shoulder of element (j) urging said sleeve in an upward direction.

Claim 6

A flow control valve for use in controlling the flow of fluids from a subsurface formation from a string of tubing which comprises: a. a lower valve biased to a closed position and positioned in a lower portion of said string of tubing; b. control means to open or close said valve; c. first means for applying a force on said control means acting to close said valve in response to fluid flow through said tubing string; d. means operable from the surface to apply a force on said control means to cause said control means to open said valve means.

Claim 7

A flow control valve for use in controlling the flow of fluids from a subsurface formation from a string of tubing which comprises: a. a lower valve biased to a closed position and positioned in a lower portion of said string of tubing; b. control means to open or close said valve; c. first means for applying a force on said control means acting to close said valve in response to fluid flow through said tubing string; d. means operable from the surface to apply a force on said control means to cause said control means to open said valve means.