U.S. patent number 3,570,595 [Application Number 04/778,157] was granted by the patent office on 1971-03-16 for hydraulically operable valves.
This patent grant is currently assigned to Schlumberger Technology Corporation. Invention is credited to William O. Berryman.
United States Patent |
3,570,595 |
Berryman |
March 16, 1971 |
HYDRAULICALLY OPERABLE VALVES
Abstract
A well packer apparatus including a body having a flow passage
and check valve means movable upwardly and downwardly in said flow
passage between positions opening and closing said flow passage to
fluid flow, a hydraulically operable piston member engageable with
said body member in response to fluid pressure tending to close
said check valve means and with said check valve means in response
to fluid pressure tending to open said check valve means and
functioning to prevent opening movement of said check valve means,
and means for selectively isolating said piston member from said
last-mentioned fluid pressure to enable opening movement of said
check valve means.
Inventors: |
Berryman; William O. (Houston,
TX) |
Assignee: |
Schlumberger Technology
Corporation (New York, NY)
|
Family
ID: |
25112466 |
Appl.
No.: |
04/778,157 |
Filed: |
November 22, 1968 |
Current U.S.
Class: |
166/128 |
Current CPC
Class: |
E21B
33/1294 (20130101) |
Current International
Class: |
E21B
33/12 (20060101); E21B 33/129 (20060101); E21b
023/00 (); E21b 033/12 () |
Field of
Search: |
;166/126,128,133,148,224--226 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Brown; David H.
Claims
I claim:
1. A well packer apparatus comprising: a body member having a flow
passage; a valve sleeve movable upwardly and downwardly in said
flow passage between position opening and closing said flow
passage, said valve sleeve having a transverse pressure area
subject to the pressure of fluids in the well bore on one side of
the well packer and to the pressure of fluids in said flow passage;
and hydraulic means having a transverse pressure area of greater
size than said transverse pressure area of said valve sleeve, said
hydraulic means being shiftable between longitudinally-spaced
positions of alternate abutting engagement with said mandrel and
said valve sleeve, said hydraulic means engaging said mandrel in
response to fluid pressure acting to close said valve sleeve, said
hydraulic means engaging and opposing movement of said valve sleeve
in response to fluid pressure acting to open said valve sleeve in
order to provide a net force on said valve sleeve to maintain it in
closed position.
2. The well packer apparatus of claim 1 further including a flow
conductor for supplying fluid under pressure to said flow passage,
said flow conductor having seal means for selectively isolating and
subjecting said hydraulic means to fluid pressure to
correspondingly permit and prevent opening movement of said valve
sleeve.
3. The well packer apparatus of claim 2 wherein said seal means is
engageable with said body member to prevent fluid pressure from
causing engagement of said valve sleeve by said hydraulic means,
thereby enabling opening movement of said valve sleeve.
4. The well packer apparatus of claim 2 wherein said seal means is
engageable with said hydraulic means to prevent fluid pressure from
causing engagement of said valve sleeve by said hydraulic means,
thereby enabling opening movement of said valve sleeve.
5. A well packer apparatus comprising: a body member having a flow
passage and carrying packing means for packing-off a well bore;
check valve means movable in said flow passage between an upper
open position and a lower closed position, said check valve means
having a downwardly facing transverse pressure surface subject to
the pressure of fluids in said flow passage to cause upward
movement to open position, and hydraulically operable means coupled
to said check valve means and having an upwardly facing transverse
pressure surface which can be selectively subjected to the pressure
of fluids in said flow passage, said upwardly facing pressure
surface having a larger area than the pressure surface of said
check valve means, whereby a predominate fluid pressure in said
flow passage will provide a net downward force on said check valve
means to maintain it in closed position.
6. The apparatus of claim 5 further including flow conductor means
extendible into said flow passage for selectively subjecting said
upwardly facing pressure surface to the pressure of fluids in said
flow passage.
7. The apparatus of claim 6 wherein said flow conductor means
includes an elongated tubular member having an annular seal packing
which is engageable with a seal surface on said body member to
enable fluid pressure in said flow passage to act downwardly on
said upwardly facing pressure surface, and with said hydraulically
operable means to isolate said upwardly facing surface from the
pressure of fluids in said flow passage.
8. A well packer apparatus comprising: a body member having a
packing element thereon sealingly engageable with a well conduit
wall, said body member having a flow passage closed at one end and
adapted to be communicated with the well bore via side ports
through the wall of said body member; valve means for selectively
opening and closing said flow passage, including a valve sleeve
movable upwardly in said flow passage to enable fluids to flow
through said side ports and downwardly in said flow passage to
prevent fluid flow, said valve sleeve having a downwardly facing
transverse pressure surface on which the pressure of fluids in said
flow passage can act to move said valve sleeve upwardly, said valve
sleeve having an upwardly facing transverse pressure surface on
which the pressure of fluids in the well bore adjacent said side
ports can act to bias said valve sleeve in closed position; and
hydraulic means including a piston member coupled to said valve
sleeve and having an upwardly facing transverse pressure surface of
larger area than said downwardly facing surface, whereby a
predominant fluid pressure in said flow passage can provide a net
downward force on said valve sleeve to maintain said valve sleeve
closed against said predominant fluid pressure.
9. . The apparatus of claim 8 further including selectively
operable means for isolating said upwardly facing surface on said
piston member from fluid pressure in said flow passage, whereby a
predominate fluid pressure in said flow passage can act upwardly on
said downwardly facing surface to move said valve sleeve upwardly
to open position.
10. The apparatus of claim 9 further including resilient means
between said piston member and said valve sleeve tending to move
said valve sleeve downwardly to closed position.
11. The apparatus of claim 9 wherein said selectively operable
means includes an elongated tubular member adapted for connection
to a pipe string extending upwardly to the earth's surface, said
tubular member having an external annular seal packing engageable
with said piston member to isolate said upwardly facing surface
from the pressure of fluids in said flow passage.
12. A well packer apparatus comprising: a body member having a flow
passage and annular packing around said body member adapted to
pack-off against a well conduit wall; check valve means movable in
said flow passage between an open position and a closed position
with respect to said flow passage; a flow conductor sealingly
received in said flow passage; and selectively releasable means on
said flow conductor and said check valve means that is engaged by
movement of said check valve means relative to said flow conductor
and toward said open position for holding said check valve means in
said open position, said releasable means being releasable in
response to movement of said flow conductor relative to said body
member to enable closing movement of said check valve means.
13. The apparatus of claim 12 wherein said releasable means
includes cooperating latch means on said flow conductor and said
check valve means, said latch means including resilient fingers on
the bottom of said flow conductor selectively engageable with
detent means on said check valve means.
14. The apparatus of claim 12 further including cam means on said
fingers engageable with a portion of said check valve means to
cause release from said detent means.
15. A well packer apparatus comprising: a tubular body member
having a packing element thereon sealingly engageable with a well
conduit wall, said body member having a flow passage closed at one
end and adapted to be communicated with the well bore via side
ports through the wall of said body member; valve means for opening
and closing said flow passage, including a valve sleeve movable
downwardly in said flow passage to enable fluids to flow through
said passage and upwardly in said flow passage to prevent fluid
flow, said valve sleeve having an upwardly facing transverse
pressure surface on which fluid pressure can act to move said valve
sleeve downwardly, said valve sleeve having a downwardly facing
transverse pressure surface on which fluid pressure in said flow
passage can act to bias said valve sleeve in closed position; and
hydraulic means including a piston member engageable with said
valve sleeve and having a downwardly facing transverse pressure
surface subject to fluid pressure tending to move said valve sleeve
downwardly, the pressure surface of said piston member having a
larger area than the pressure surface on said sleeve member to
provide a net upward force on said valve sleeve to maintain it in
closed position.
16. The well packer apparatus of claim 15 further including means
for isolating said piston member from fluid pressure tending to
move said valve sleeve downwardly, thereby enabling said fluid
pressure to cause opening movement of said valve sleeve.
17. The well packer apparatus of claim 16 wherein said isolating
means includes a flow conductor telescopically received on said
body member, said flow conductor having sealing means thereon
engageable with said body member below said side ports.
Description
This invention relates generally to well tools used in well bores,
and more specifically to hydraulically operated valves for use in
controlling fluid flow through a well packer.
Valved well packers such as squeeze retainers generally include a
central mandrel having a flow passage and some type of valve
arrangement for opening and closing the flow passage. When the
valve is open, fluids such as cement slurry, acid or hydraulic
fracturing fluids can be forced under pressure into the well bore
below the packer, and the valve can be closed in order to trap the
fluids at developed pressures.
Several types of valve constructions have been used in the past.
U.S. Pat. No. 2,196,661, for example, discloses a floating ball
check valve which is forced open by fluids flowing downwardly
through the mandrel, and when the flow is stopped, the ball will
seat and is held closed by pressure trapped below the packer.
Although this type of valve is relatively simple, it is subject to
the disadvantage that should pressure subsequently be applied to a
region above the packer, the ball will unseat and allow fluid flow.
Another type of valve construction is shown in U.S. Pat.
No.3,306,363, which relates to a valve sleeve movable upwardly and
downwardly by a mechanical member in order to open and close
lateral ports in the mandrel. This type of valve has the advantage
that it can be constructed to be insensitive to fluid pressure and
will remain closed regardless of pressure. However, the mechanical
coupling between the member and valve sleeve may be somewhat
complex and subject to operational problems in a well bore.
Moreover, a mechanically operable valve may be difficult to move
when cement slurry has been pumped through it and the valve held
open for even a short length of time before an attempt is made to
close it.
It is an object of the present invention to provide a new and
improved valve construction for use in controlling fluid flow
through a well packer, which has the advantage of simplicity found
in hydraulically operated check valves, yet which will remain
closed even though pressure is imposed from either side.
This and other objects are attained in accordance with the
principles of the present invention by a well packer apparatus
including a body member having a flow passage and carrying normally
retracted slips and packing means for providing an anchored packoff
in a well bore. A check valve means is movable in said flow passage
between positions opening and closing said flow passage and is
provided with a transverse pressure surface which is subject to the
pressure of fluids in the flow passage as well as below the packing
means. A hydraulically operable force-transferring means is movable
between spaced positions of alternate engagement with the body
member and the check valve means, said transferring means having a
transverse pressure area greater in size than the pressure area of
said check valve means. The force transferring means is arranged to
engage the body member in response to a fluid pressure acting to
close said check valve means, and to engage said check valve means
in response to a fluid pressure acting to open said check valve
means, and providing a net force on said check valve means to
maintain it in closed position. According to one embodiment of the
present invention, a flow conductor is telescopically movable in
said flow passage and has a seal element which is selectively
engageable with said body member to enable fluid pressure to act on
said force-transferring means and to maintain said check valve
means closed, and with said transferring means itself to isolate
said transferring means from the pressure of fluids in said flow
passage, whereby a predominance of fluid pressure in said flow
passage can act on said check valve means to cause opening movement
thereof. In accordance with another embodiment of the present
invention, a flow conductor is cooperable with the body member to
isolate the transferring means from the fluid pressure acting to
move said check valve means to open position, thus enabling
movement of the check valve means to open position.
The present invention has other objects and advantages which will
become more clearly apparent in connection with the following
detailed description of several embodiments taken in conjunction
with the appended drawings, in which:
FIG. 1 is a longitudinal sectional view, with portions in side
elevation, of a well packer including the valve assembly of the
present invention;
FIG. 2 is an enlarged cross section view showing greater detail of
the valve assembly;
FIG. 3 is a sectional view showing the valve assembly during
testing of the pipe string for leaks;
FIG. 4 is a sectional view showing the valve assembly opened and
held open to enable flow of fluids in either direction;
FIG. 5 is a sectional view showing release of the latch mechanism
to permit the valve assembly to close;
FIG. 6 is a sectional view of the valve assembly with the flow
conductor removed;
FIG. 7 is a cross-sectional view of a modified form of valve
assembly in accordance with the present invention with the valve
closed in response to pressure from above;
FIG. 8 shows the valve remaining closed in response to fluid
pressure from below; and
FIG. 9 shows a flow conductor telescoped over the body member and
the valve opened to fluid flow in a downward direction.
Referring initially to FIG. 1, a well packer 10 is shown which can
be set in a cased well bore. The well packer 10 includes a central
mandrel or body member 12 which carries normally retracted upper
and lower slips 13 and 14 and companion expander cones 15 and 16.
An elastomeric, expansible packing structure 17 which can be
constituted by several annular rings is mounted around the mandrel
12 between the expander cones. In conventional fashion, when the
mandrel 12 is forced upwardly and the upper slip 13 is forced
downwardly, the slips 13 and 14 will be shifted outward by the
respective expander cones 15 and 16 into gripping engagement with a
well casing wall, and the packing structure 17 will be compressed
between expander cones and expanded outwardly to pack-off casing. A
conventional one-way clutch ring 18 can be used to trap the slips
and packing in set positions. Other conventional elements such as
shear pins and antiextrusion rings can be provided but are not
shown.
The body member 12 has a central bore providing a flow passage 19
which is closed at its lower end by a plug 20. Several ports 22
extend radially through the wall portion 23 of the body member in
order to communicate with the well bore below the packing 17. An
internal annular recess 24 is formed in the body portion 23
adjacent the ports 22 and is arranged to receive a valve assembly
generally indicated at 25. The valve assembly 25 includes a valve
sleeve 26 and a force-transferring piston member 27 to be fully
described hereafter, the valve sleeve 26 being movable between
longitudinally-spaced positions to effect opening and closing of
the flow passage 19 to fluid flow.
Telescopically recieved within the bore 19 of the body member 12 is
a flow conductor or "stinger" 28. The flow conductor 28 is coupled
to the lower end of a pipe string 29 which extends upwardly to the
top of the well bore, and through which fluids under pressure can
be pumped into the well bore below the packer 10. A suitable
mechanical stop assembly 30 is provided to limit longitudinal
movement of the flow conductor 28 in longitudinally-spaced
positions. Although the stop assembly can take many forms, the
structure illustrated is constituted by an annular, split stop ring
31 which is slidably and corotatively secured to the flow conductor
28 by a spline 32 which engages in the split in the ring. The ring
31 is radially expansible and contractable and is cooperable with
longitudinally-spaced thread portions 33 and 34 formed on the inner
periphery of the mandrel 12. When the ring 31 engages the upper
thread portion 33 as shown in FIG. 1, the flow conductor 28 can be
reciprocated by the pipe string 29 between a lower position where
an annular shoulder 35 engages an upper end surface of the mandrel
12, and an upper position where an upwardly facing shoulder 37 on
the flow conductor engages the stop ring 31. The stop ring 31 can
be selectively engaged and disengaged from the mandrel by
appropriate manipulation of the pipe string, and further details of
the stop assembly 30 are described in U.S. Pat. No. 3,433,304 which
is assigned to the assignee of the present invention.
As shown in greater detail in FIG. 2, the lower end portion of the
flow conductor 28 is longitudinally slotted, the slots 39 dividing
the lower portion into a plurality of elongated fingers 40 having a
degree of lateral flexibility. A section of upwardly facing
buttress-type threads 41 are formed on the outer periphery of each
finger 40, the threads being mateable with internal threads 42
formed on the valve sleeve 26. An upward movement of the valve
sleeve 26 when the flow conductor 28 is in its lower position will
cause the threads 41 on the fingers 40 to ratchet into the threads
42, thereby coupling the flow conductor 28 and valve sleeve 26
together with the valve sleeve in its upper or open position. The
fingers 40 can be released from the valve sleeve 26 by pulling the
flow conductor upwardly until annular projections 43 formed on each
finger engage an inclined surface 44 on the member 27. This will
cause the fingers 40 to resile inwardly and release the threads 41
from the valve sleeve threads 42, enabling the valve sleeve 26 to
return to closed position.
As previously mentioned, the valve assembly 25 includes a transfer
piston member 27 and a valve sleeve 26. The piston member 27 and
the valve sleeve 26 are telescopically movable relative to each
other, and a seal ring 46 prevents any fluid leakage between them.
The piston member 27 has an annular flange portion 47 which is
sealed against the wall of the recess 24 by a seal ring 48, whereas
the lower portion 49 of the valve sleeve 26 is reduced somewhat in
diameter and is sealed by a suitable packing ring 50 against a seal
surface 51 on the body member 12. The outer periphery of he valve
sleeve 26 is sized relative to the recess 24 such that a space 52
is provided therebetween to communicate at all times the lower face
53 of the flange portion 47, as well as the upper face 54 of the
valve sleeve 26, with the fluid pressure in the well bore below the
packing element 17 via the side ports 22. A coil spring 56 is
positioned to surround the piston member 27 and is arranged to
press upwardly on the flange portion 47 and downwardly on the upper
end of the valve sleeve 26. The spring 56 functions to yieldably
retain the valve sleeve 26 in the position shown in FIG. 2, but
will foreshorten and enable either the piston member 27 to shift
downwardly, or the valve sleeve 26 to shift upwardly.
The various seals 46, 48 and 50 engage on different diameters, the
seal diameter D-1 for the packing ring 50 being intermediate the
respective seal diameters D-2 and D-3 for the rings 46 and 48. In
this manner, the valve sleeve 26 has an effective pressure area A
equal to the difference in cross-sectional or transverse areas
defined by the seal diameters D-1 and D-2 whereas the piston member
27 has an effective pressure area B equal to the difference in
transverse areas defined by the seal diameters D-2 and D-3. The
area B, as shown, is somewhat larger than the area A. The flow
conductor 28 carries a seal ring 58 which can sealingly engage
either a body member seal surface 59, or the inner peripheral
surface 60 of the piston member 27. When the seal ring 58 engages
the surface 59, the area B is exposed to fluid pressure in the flow
passage 19; when the seal ring 58 engages the surface 60, the area
B is isolated from fluid pressure in the flow passage 19. The seal
packing 58 is engageable with the body member seal surface 59 when
the flow conductor 28 is in its upper limit position as previously
described, and with the inner surface 60 of the sleeve member 27
when the flow conductor is placed in its lower limit position.
In operation, the packer 10 can be set in a conventional manner by
a wire line or a mechanical setting tool, such tools being well
known to those skilled in the art. The upper and lower slips 13 and
14 are anchored to respectively prevent upwardly and downwardly
movement, and the packing structure 17 seals off the well annulus
between the body member 12 and the surrounding well casing wall. In
case the packer 10 has been previously set on wire line, the flow
conductor 28 can be lowered into the well bore and at the end of
the pipe string 29 and inserted into the bore 19 of the body member
12, after which a pressure operation can be performed. If it is
desired to pressure test the pipe string 29 for leaks prior to
performance of a pressure operation, this can be accomplished by
properly positioning the flow conductor 28 within the body member
12 such that the seal packing 58 is against the body seal surface
59 as shown in FIG. 3. This position can correspond to the upper
limit position of the flow conductor 28 where the shoulder 37
engages the stop ring 31. With a predominance of fluid pressure
applied in the flow passage 19, the pressure will act downwardly
over the area B and upwardly over the area A, causing the piston
member 27 to shift downwardly, as shown in FIG. 3, compressing the
spring 56 and transferring the pressure force imposed upon it to
the valve sleeve 26. Since the area B is larger than the area A,
the resultant force on the valve sleeve 26 is directed downwardly
to maintain the packing ring 50 sealed against the seal surface 51.
Accordingly the valve sleeve 26 remains in closed position with
respect to the side ports 22, and the pipe string 29 can be tested
for leaks.
In order to pump fluids into the well bore below the packer 10, the
flow conductor 28 is moved downwardly to its lower limit position
where the seal packing 58 engages the inner surface 60 of the
piston member 27 as shown in FIG. 4. Now the upper end surfaces of
the piston member 27 are isolated from fluid pressure in the flow
passage 19, and such fluid pressure cannot act downwardly thereon.
Thus, a predominance of fluid pressure in the flow passage 19 will
cause the valve sleeve 26 to respond like a check valve, that is to
say, the pressure will act upwardly on the area A and shift the
valve sleeve upwardly and disengage the packing ring 50 from the
seal surface 51. This mode of operation is shown in FIG. 4, with
fluid flowing outwardly through the side ports 22 holding the valve
sleeve 26 in an upper position.
When the valve sleeve 26 shifts upwardly, the teeth 42 are
ratcheted over the corresponding teeth 41 on the fingers 40,
coupling the valve sleeve temporarily against downward movement.
Thus, the valve sleeve 26 is held open, so that an operator at the
surface can check for "flowback." In pressure operations such as
squeeze cementing, it is sometimes desirable to check for flowback,
that is to say, to hold the valve open and discover by observing
surface flow conditions whether or not the cement slurry is being
forced back into the well bore through the perforations. This
occurrence would indicate that the slurry has not hardened or set
up sufficient to conclude the operation, or perhaps an acceptable
cement squeeze has not been obtained. In any event, since the valve
sleeve 26 is being held open, a flow of fluids from the running-in
string at the surface will indicate that the cement slurry is being
forced back into the casing, and that a successful squeeze is yet
to be obtained.
When it is desired to close the valve sleeve 26, the flow conductor
28 is again moved to its upper position, such upward movement
causing the annular projections 43 on the latch fingers 40 to
engage the inclined surface 44 on the piston member 27, resulting
in inward flexing of the fingers and release of the threads 41 and
42 as shown in FIG. 5. The spring 56 can now function to push the
valve sleeve 26 downwardly to the closed position shown in FIG. 2.
With the flow conductor 28 removed as shown in FIG. 6, the valve
sleeve 26 will remain in closed position whether pressure is
imposed from above or below. A greater pressure from below will act
through the ports 22 and downwardly on the area A to bias the valve
closed. A greater pressure from above will act downwardly on the
area B of the piston member 27 and upwardly on the area A of the
valve sleeve 26. Since the area B is greater than the area A, the
net result is a downward force on the valve sleeve 26 with the
piston member shifting downwardly and engaging the valve sleeve as
shown in FIG. 3.
Referring now to FIG. 7, a modified form of the present invention
is illustrated. In the previously described embodiment, the bore of
the mandrel or body member was closed at its lower end and the
valve assembly and side ports located below the packing structure.
In this embodiment, however, the flow passage 119 of the body
member 112 is closed by a partition 120 at its upper end, and side
ports 122 communicate with the well bore above the packing (not
shown). The body member 112 has a stepped internal recess 124, and
movably received in the flow passage 119 is a valve sleeve 126
having an upper packing ring 150 engageable with a seal surface 151
above the ports 122, and an enlarged flange portion 149 carrying a
seal ring 146 which is engageable with the wall surface 159 below
the ports. The valve sleeve 126 has a depending skirt 155 with a
smaller outer diameter than the upper portion 157 of the valve
sleeve, fluid leakage between the skirt 155 and the body member 112
being prevented by a seal ring 148.
A transfer piston 127 is movably received in the annular cavity 162
between the skirt 155 and the mandrel wall portion 163. Inner and
outer rings 164 and 165 seal respectively against the skirt 155 and
the wall surface 159 of the portion 163. The cavity space below the
piston 127 is communicated with the well bore by one or more ports
167, whereas the cavity space above the piston is communicated with
the flow passage 119 via one or more ports 168 through the skirt
155 below the flange portion 149. A suitable coil spring 156 is
arranged to urge the transfer piston 127 upwardly, and, in the
valve position shown in FIG. 7, to bias the valve sleeve 126
upwardly toward closed position.
The valve system will remain in closed position against pressure
imposed from above or below in the following manner. In response to
a grater fluid pressure in the well bore above the packer, the
pressure will act through ports 122 downwardly on the packer, the
pressure will act through ports 122 downwardly on the upwardly
facing transverse surface 169 of the valve sleeve. However, the
pressure will also act through the ports 167 upwardly on the
downwardly facing surface 170 of the transfer piston 127. Inasmuch
as the transverse area of the transfer piston 127 is greater than
the transverse are of the flange portion 149, the net force due to
greater pressure from above is directed upwardly on the valve
sleeve 127 to maintain it in closed position as shown in FIG.
7.
In response to greater fluid pressure in the well bore below the
packer, the valve sleeve 126 will remain in closed position as
shown in FIG. 8. The greater pressure will act via the skirt ports
168 on the upper face 171 of the transfer piston 127, shifting it
downwardly and against the body shoulder 172. The same pressure
also acts upwardly on the lower face 173 of the flange portion 149.
Inasmuch as the lesser fluid pressure is communicated via the ports
122 to the upper face 169 of the flange portion 149, an upward
force is applied to the valve sleeve 126 to maintain it in closed
position as shown in FIG. 8.
In order to pump fluid under pressure through the flow passage 119
and into the well bore below the packer, a flow conductor 128 is
positioned in the well bore and telescoped over the body member 112
as shown in FIG. 9. The flow conductor 128 has an inwardly
extending annular portion 174 carrying a seal packing 158 which
engages the body member below the ports 122 and prevents fluid
leakage. Fluid pressure inside the flow conductor 128 will act
through the side ports 122 and on the upper face 169 of the flange
portion 149 to force the valve sleeve 126 downwardly to its open
position as shown. The seal packing 158, of course, confines the
greater pressure to the passage 119 and prevents the greater
pressure from acting via the ports 167 on the lower side of the
transfer piston 127. Fluids flowing past the valve sleeve 126 will
maintain it in open condition until the flow is discontinued,
whereupon the spring 156 will force the valve sleeve upwardly to
its closed position as illustrated in FIG. 7.
Certain new and improved well packer valve systems have been
disclosed, the valve systems having the simplicity of a check
valve, yet being constructed and arranged to hold pressure from
above or below. According to one embodiment, the valve can be held
open to check for backflow of fluids, and the surface manipulations
required to operate the valve are constituted primarily by simple
upward and downward movement of the pipe string. Since certain
changes and modifications will become apparent to those skilled in
the art in view of the foregoing disclosure without departing from
the inventive concepts involved, it is the aim of the appended
claims to cover all such changes and modifications falling within
the true spirit and scope of the present invention.
* * * * *