Isolation gravel packer

Claim 2

A well treatment apparatus of a type to be disposed within a conduit in a well bore, in fluid communication with first and second tubing means, said apparatus comprising: treatment means containing first and second passage means, check valve means, and third passage means; said first passage means in fluid communication with said first tubing means above said treatment means and with the bore of said conduit below said treatment means; said second passage means in fluid communication with said second tubing means above said treatment means and with the annulus between said treatment means and said conduit; said check valve means being disposed in said first passage means; and said third passage means being longitudinally fixed and in fluid communication with said annular and with said first passage means above said check valve means.

Claim 3

The apparatus of claim 1, wherein said check valve means permits flow in an upward direction, and prohibits flow in a downward direction.

Claim 4

The apparatus of claim 2, further comprising: first and second seal means disposed around said treatment means to bracket said annulus communication point of said second passage means; and third seal means disposed around said treatment means, said annulus communication point of said third passage means being interposed between said third seal means and said second seal means.

Claim 5

The apparatus of claim 3 wherein said first and second seal means effect a fluid seal between said treatment means and said conduit means in response to fluid flow out of said second passage means communication point.

Claim 6

The apparatus of claim 4 wherein said first and third seal means effect a fluid seal between said treatment means and said conduit means in response to fluid flow out of said third passage means annulus communication point, and said second seal means releases its seal in response thereto.

Claim 7

The apparatus of claim 5, further comprising: fourth seal means disposed around said treatment means below the annulus communication points of said second and third passage means, said fourth seal means effecting a seal in response to a negative pressure differential above said fourth seal means.

Claim 8

The apparatus of claim 6 wherein said first and second tubing means comprise, respectively, the bore of a first tube and the space between said first tube and a second, larger tube, said treatment means being attached to said first and second tubes.

Claim 9

The apparatus of claim 7 wherein said first and second tubes are concentric.

Claim 10

The apparatus of claim 6 wherein said first tubing means comprises the bore of a tubing string and said second tubing means comprises the annulus between said tubing string and said conduit.

Claim 11

The apparatus of claim 6, further comprising: selective fluid bypass means in said treatment means; said selective fluid bypass means permitting fluid communication between the conduit bore above and that below said treatment means when open, and prohibiting said fluid communication when closed.

Claim 12

The apparatus of claim 10 wherein said selective fluid bypass means is opened and closed by application of longitudinal force on said treatment means.

Claim 13

The apparatus of claim 11 wherein said selective fluid bypass means is opened by upward force, and closed by downward force.

Claim 14

The apparatus of claim 12, further comprising: selective dump valve means in said treatment means; said selective dump valve means permitting fluid communication between the conduit bore above said treatment means and the annulus bounded by said first and second seal means when open, and prohibiting such fluid communication when closed.

Claim 15

The apparatus of claim 13 wherein said second tubing means comprises the bore of a tube, and said first tubing means comprises the annulus between said tube and said conduit.

Claim 16

The apparatus of claim 13 wherein said selective dump valve means is opened and closed by application of longitudinal force on said treatment means.

Claim 17

The apparatus of claim 15 wherein said selective dump valve means is opened by upward force, and closed by downward force.

Claim 18

The apparatus of claim 16 wherein said upward and downward forces are applied to said treatment means by at least one of said tubing means.

Claim 19

The apparatus of claim 17 further comprising fifth seal means proximate the top of said treatment means, said fifth seal means effecting a seal between said treatment means and said conduit in response to a positive pressure differential above said treatment means.

Claim 20

The apparatus of claim 18 further comprising: first and second seal means disposed around said gravel packer, bracketing said second passage annulus entry; and third seal means disposed around said gravel packer, said third passage annulus entry being located between said second and third seal means.

Claim 21

The apparatus of claim 19 wherein said first and second seal means effect a seal between said gravel packer and said liner in response to fluid flow out of said second passage annulus entry; and said first and third seal means effect a seal between said gravel packer and said liner in response to fluid flow out of said third passage annulus entry.

Claim 22

The apparatus of claim 20 further comprising fourth seal means at the lower end of said gravel packer; said fourth seal means effecting a fluid seal between said gravel packer and said liner in response to a negative pressure differential above said fourth seal means.

Claim 23

The apparatus of claim 21 wherein said first, second, third and fourth seal means comprise packer cups.

Claim 24

The apparatus of claim 21 wherein said first tubing means comprises the bore of a first tube, and said second tubing means comprises the space between said first tube and the inner wall of a second, larger tube disposed thereabout.

Claim 25

The apparatus of claim 21 wherein said second tubing means comprises a tube, and said first tubing means comprises the annulus between said tube and said liner.

Claim 26

The apparatus of claim 21 wherein said second tubing means comprises a tube, and said first tubing means comprises the space between said tube and the inner wall of a second, larger tube disposed thereabout.

Claim 27

The apparatus of claim 21 wherein said first tubing means comprises the bore of a tube, and said second tubing means comprises the annulus between said tube and said liner.

Claim 28

The apparatus of claim 26 further comprising fifth seal means proximate the top of said treatment means, said fifth seal means effecting a seal between said treatment means and said conduit in response to a positive pressure differential above said treatment means.

Claim 29

The apparatus of claim 21 further comprising a selectively closable fluid bypass in said gravel packer; said fluid bypass extending from said liner bore above said gravel packer to said liner bore below said gravel packer.

Claim 30

The apparatus of claim 28 wherein said bypass is selectively closed by a sliding valve assembly responsive to axial force applied to said gravel packer.

Claim 31

The apparatus of claim 29 wherein the direction of said axial closing force is downward.

Claim 32

The apparatus of claim 30 wherein said axial closing force is applied through at least one of said tubing means.

Claim 33

The apparatus of claim 21 further comprising a selectively closable dump valve in said gravel packer; said dump valve extending from said liner bore above said gravel packer to said annulus between said first and second seal means.

Claim 34

The apparatus of claim 32 wherein said dump valve is selectively closed by a sliding valve assembly responsive to axial force applied to said gravel packer.

Claim 35

The apparatus of claim 32 wherein the direction of said axial closing force is downward.

Claim 36

The apparatus of claim 34 wherein said axial closing force is applied through at least one of said tubing means.

Claim 37

An isolation gravel packer of the type in fluid communication with first and second tubing means within a liner in a well bore, said liner having ports therein and a gravel screen below said ports, said isolation gravel packer comprising: gravel packer means having first, second and third passages therethrough, and a check valve; said first passage extending from said first tubing means to the bore of said liner below said gravel packer; said second passage extending from said second tubing means to the annulus between said gravel packer and said liner; said third passage being longitudinally fixed in said gravel packer means and extending between first passage and said annulus; and said check valve being disposed in said first passage below said third passage.

Claim 38

An isolation gravel packer of the type in fluid communication with first and second tubing means within a liner in a well bore, said liner having ports therein and a gravel screen below said ports, said isolation gravel packer comprising: gravel packer means having first, second and third passages therethrough, and a check valve; said first passage extending from said first tubing means to the bore of said liner below said gravel packer; said second passage extending from said second tubing means to the annulus between said gravel packer and said liner; said third passage being longitudinally fixed in said gravel packer means and extending between first passage and said annulus; and said check valve being disposed in said first passage below said third passage.

Claim 39

The apparatus of claim 36 wherein said check valve means permits flow in an upward direction, and prohibits flow in a downward direction.

Claim 44

The method of claim 39, wherein said reversing circulation is effected without inducing fluid movement across said packed zone.

Claim 45

A well treatment apparatus of a type to be disposed within a conduit in a well bore, in fluid communication with first and second tubing means, said apparatus comprising: treatment means containing first and second passage means, check valve means, and third passage means; said first passage means in fluid communication with said first tubing means above said treatment means and with the bore of said conduit below said treatment means; said second passage means in fluid communication with said second tubing means above said treatment means and with the annulus between said treatment means and said conduit; said check valve means being disposed in said first passage means; said third passage means in fluid communication with said annulus and with said first passage means above said check valve means; first and second seal means disposed around said treatment means to bracket said annulus communication point of said second passage means; and third seal means disposed around said treatment means, the annulus communication point of said third passage means being interposed between said third seal means and said second seal means.

Claim 46

A well treatment apparatus of a type to be disposed within a conduit in a well bore, in fluid communication with first and second tubing means, said apparatus comprising: treatment means containing first and second passage means, check valve means, and third passage means; said first passage means in fluid communication with said first tubing means above said treatment means and with the bore of said conduit below said treatment means; said second passage means in fluid communication with said second tubing means above said treatment means and with the annulus between said treatment means and said conduit; said check valve means being disposed in said first passage means; said third passage means in fluid communication with said annulus and with said first passage means above said check valve means; first and second seal means disposed around said treatment means to bracket said annulus communication point of said second passage means; and third seal means disposed around said treatment means, the annulus communication point of said third passage means being interposed between said third seal means and said second seal means.

Claim 47

The apparatus of claim 41, wherein said check valve means permits flow in an upward direction, and prohibits flow in a downward direction.

Claim 48

The apparatus of claim 42, wherein said first and second seal means effect a fluid seal between said treatment means and said conduit means in response to fluid flow out of said second passage means communication point.

Claim 49

The apparatus of claim 43 wherein said first and third seal means effect a fluid seal between said treatment means and said conduit means in response to fluid flow out of said third passage means annulus communication point, and said second seal means releases its seal in response thereto.

Claim 50

The apparatus of claim 44, further comprising: fourth seal means disposed around said treatment means below the annulus communication points of said second and third passage means, said fourth seal means effecting a seal in response to a negative pressure differential above said fourth seal means.

Claim 51

The apparatus of claim 45, further comprising: selective fluid bypass means in said treatment means; said selective fluid bypass means permitting fluid communication between the conduit bore above and that below said treatment means when open, and prohibiting said fluid communication when closed.

Claim 52

The apparatus of claim 46, wherein said selective fluid bypass means is opened and closed by application of longitudinal force on said treatment means.

Claim 53

The apparatus of claim 47, wherein said selective fluid bypass means is opened by upward force, and closed by downward force.

Claim 54

The apparatus of claim 48, further comprising: selective dump valve means in said treatment means; said selective dump valve means permitting fluid communication between the conduit bore above said treatment means and the annulus bounded by said first and second seal means when open, and prohibiting such fluid communication when closed.

Claim 55

The apparatus of claim 49, wherein said selective dump valve means is opened and closed by application of longitudinal force on said treatment means.

Claim 56

The apparatus of claim 50, wherein said selective dump valve means is opened by upward force, and closed by downward force.

Claim 57

The apparatus of claim 51, wherein said upward and downward forces are applied to said treatment means by at least one of said tubing means.

Claim 58

The apparatus of claim 52, wherein said first and second tubing means comprise, respectively, the bore of a first tube and the space between said first tube and a second, larger tube, said treatment means being attached to said first and second tubes.

Claim 59

The apparatus of claim 53, wherein said first and second tubes are concentric.

Claim 60

The apparatus of claim 54, wherein said first tubing means comprises the bore of a tubing string and said second tubing means comprises the annulus between said tubing string and said conduit.

Claim 61

The apparatus of claim 55, further comprising fifth seal means proximate the top of said treatment means, said fifth seal means effecting a seal between said treatment means and said conduit in response to a positive pressure differential above said treatment means.

Claim 62

The apparatus of claim 56, wherein said second tubing means comprises the bore of a tube, and said first tubing means comprises the annulus between said tube and said conduit.