Note: Descriptions are shown in the official language in which they were submitted.
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APPARATUS FOR SELECTABLY
PERMITTING FLUIDIC COMMUNICATION BETWEEN
AN INTERIOR AND AN EXTERIOR OF A WELL ASSEMBLY
BACKGROUND OF THE INVENTION
t Field of Invention
The present invention relates to hydrocarbon well control in general and in
particular methods and apparatuses for selectably opening and closing zones
within a hydrocarbon well during completion, hydraulic fracturing or
production.
2. Description of Related Art
In hydrocarbon production, it has become common to utilize directional or
horizontal drilling to reach petroleum containing rocks, or formations, that
are
either at a horizontal distance from the drilling location. Horizontal
drilling is
also commonly utilized to extend the wellbore along a horizontal or inclined
formation or to span across multiple formations with a single wellbore. With
horizontal drilling the well casing Is prone to resting upon the bottom of the
wellbore requiring the use of spacers so as to centre the casing within the
wellbore.
In horizontal hydrocarbon wells, it is frequently desirable to select which
zone
of the wellbore is to be opened for production or to stimulate one or more
zones of the well to increase production of that zone from time to time. One
current method of stimulating a portion of the well is through the use of
hydraulic fracturing or frocking. One difficulty with conventional tracking
systems, it that is necessary to Isolate the zone to be stimulated on both the
upper and lower ends thereof so as to limit the stimulation to the desired
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zone. Such isolation has typically been accomplished with sealing elements
known as production packers located to either side of the zone to be isolated.
The use of such
One of the prior problems with current tracking methods is that most
hydrocarbon wells are constructed with a well casing located within the
wellbore which is cemented in place by pumping cement down the casing to
the bottom of the well so as to fill the annulus between the casing and the
wellbore from the bottom up. Such concrete provides an additional barrier
between the center of the well casing and wellbore which is to be tracked. In
conventional methods, in order to thereafter track a zone which has been
constructed in such a manner, it is necessary to form a conduit from the
interior of the casing to the wellbore wall by fracturing the cement as well
as
the formation. Needing to fracture the concrete as well as the formation
increases the pressure required for the tracking process thereby increasing
the equipment requirements as well as the resulting cost and time
requirements.
Previous attempts to resolve some of the above difficulties has been to
provide
valves inline within the casing so as to selectably provide access to the
desired
zones of the well. Such valves may be sliding valves having actuators such as
are described in US Patent Application Publication No. 2006/0207763 to
Hofman published September 21, 2006. With the use of such sliding valves
however, it is still necessary to fracture, dissolve or otherwise perforate
the
concrete surrounding the casing to access the formation.
SUMMARY OF THE INVENTION
According to a first embodiment of the present invention there is disclosed an
apparatus for selectably permitting fluidic communication between an interior
and an exterior of a well assembly comprising a tubular body extending
between first and second ends and having a central passage extending
therebetween, the first and second ends being connectable to the well
assembly such that the central passage is in fluidic communication with an
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interior of the well assembly. The apparatus further includes at least one set
of passages extending through the tubular body between the central passage
and an exterior of the tubular body and a sleeve slidably located within the
central passage of the valve body adapted to selectably sealably cover or
uncover the at least one sets of passages. The apparatus further includes a
shifting tool slidably locatable within the sleeve at an end of a tool string
the
shifting tool being engagable upon the sleeve so as to permit the shifting
tool
to move the sleeve longitudinally within the tubular body.
The apparatus may further comprise first and second sets of passages
extending through the tubular body. The sleeve may be locatable at a first
position covering both of the first and second sets of passages, a second
position covering the first set of passages and uncovering the second set of
passages and a third position uncovering the first set of passages and
covering the second set of passages. The second set of passages may
include flow channels extending along the tubular body and having a filter
located therearound. The second set of passages may include a plurality of
outlet nozzles positioned to direct a flow of fluid to the exterior of the
well
assembly. The nozzles may be oriented substantially parallel to a central axis
of the tubular member.
The shifting tool may comprise a body having a central bore extending
therethrough and an outer surface, at least one shifting bore extending from
the central bore wherein each shifting bore includes an actuating piston
located therein and first and second key bores extending radially inwards from
the outer surface. The shifting tool may also include first and second piston
keys located within the first and second key bores wherein each of the first
and second piston keys has sleeve engaging surface thereon spaced apart by
a distance selected to retain the sleeve therebetween. Each of the first and
second piston keys may be operably connected to the actuating piston so as
to be extended from the outer surface when the central bore is supplied with a
pressurized fluid.
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The first and second piston keys and the actuating piston may be each
operably connected to a common shaft with arms extending from the shaft.
The shaft and the arms may be contained within a chamber in the body. The
chamber may be in fluidic communication with the outer surface of the body
through a balancing bore. The balancing bore may include a filter therein.
The shaft may be biased to urge the first and second piston keys to a
retracted position. The shaft may be biased by at least one spring biasing a
spring arm extending from the shaft. The spring may be located within a
spring bore extending from the outer surface of the body and is compressed
between the spring arm and an adjusting cap located within the spring bore.
The adjusting cap may be threadably located within the spring bore.
The central passage may include at least one annular groove therein
corresponding to a desired position of the sleeve valve wherein the sleeve
includes a retaining ring disposed there around receivable within the at least
one annular groove. The retaining ring may comprise a split ring surrounding
the sleeve having a radially biasing spring between the split ring and the
sleeve. The split ring and the radially biasing spring may be located within
an
annular groove around the sleeve. The annular groove may include sloped
sidewalls and wherein the radially biasing spring has a biasing force selected
to be retained within the annular groove once a predetermined displacing
force has been applied to the tool string.
According to a further embodiment of the present invention there is disclosed
a
method of controlling fluid flow through a well comprising providing a tubular
body inline within the well, the tubular body extending between first and
second ends and having a central passage extending therebetween, the first
and second ends being connectable to the well assembly such that the central
passage is in fluidic communication with an interior of the well assembly. The
method further comprises engaging a shifting tool upon a sleeve located
within the tubular body and longitudinally displacing the shifting tool
relative to
the tubular body so as to selectably uncover at least one set of passages
extending through the tubular body.
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According to a further embodiment of the present invention there is disclosed
a method for
hydraulically fracturing a soil formation at a zone surrounding a well liner
comprising locating
a tool string with a shifting tool at a distal end thereof within a tubular
body of the well liner,
engaging the shifting tool upon a sleeve corresponding to the zone,
longitudinally displacing
the tool string so as to uncover at least one set of passages extending
through the tubular
body and pumping a fracturing fluid down an annulus formed between the tool
string and the
well liner. The annulus may substantially unobstructed.
According to a further embodiment of the present invention there is disclosed
a method for
hydraulically fracturing a soil formation at a zone surrounding a well liner
comprising locating
a tool string with a shifting tool at a distal end thereof within a tubular
body of the well liner,
engaging the shifting tool upon a sleeve corresponding to the zone and
longitudinally
displacing the tool string so as to uncover at least one set of passages
extending through the
tubular body. The method further comprises pumping a fracturing fluid down the
tool string
and releasing the fracturing fluid from the tool string into an annulus formed
between the tool
string and the well liner through a valve.
According to further embodiments of the present invention, there is disclosed
an apparatus
for selectably permitting fluidic communication between an interior and an
exterior of a well
assembly comprising: a tubular body extending between first and second ends
and having a
central passage extending therebetween, said first and second ends being
connectable to
said well assembly such that said central passage is in fluidic communication
with an interior
of said well assembly; at least one set of passages extending through said
tubular body
between said central passage and an exterior of said tubular body; a sleeve
slidably located
within said central passage of said tubular body adapted to selectably
sealably cover or
uncover said at least one sets of passages; and a shifting tool slidably
locatable within said
sleeve at an end of a tool string said shifting tool being engagable upon said
sleeve so as to
permit said shifting tool to move said sleeve longitudinally within said
tubular body, wherein
said shifting tool comprises: a body having a central bore extending
therethrough and an
outer surface; at least one shifting bore extending from said central bore
wherein each
shifting bore includes a actuating piston located therein; first and second
key bores extending
radially inwards from said outer surface; and first and second piston keys
located within said
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first and second key bores, each of said first and second piston keys having
sleeve engaging
surface thereon spaced apart by a distance selected to retain said sleeve
therebetween,
wherein each of said first and second piston keys are operably connected to
said actuating
piston so as to be extended from said outer surface when said central bore is
supplied with a
.. pressurized fluid.
Other aspects and features of the present invention will become apparent to
those ordinarily
skilled in the art upon review of the following description of specific
embodiments of the
invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
In drawings which illustrate embodiments of the invention wherein similar
characters of
reference denote corresponding parts in each view,
Figure 1 is a cross-sectional view of a wellbore having a plurality of
flow control valves
according to a first embodiment of the present invention located therealong.
Figure 2 is a perspective view of one of the control valves of Figure 1.
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Figure 3 is a longitudinal cross-sectional view of the control valve
of Figure
2 as taken along the line 3-3.
Figure 4 is a detailed cross-sectional view of the extendable ports of
the
valve of Figure 2 in a first or retracted position.
Figure 5 is a detailed cross-sectional view of the extendable ports of the
valve of Figure 2 in a second or extended position with the sleeve
valve in an open position.
Figure 6 is a partial cross-sectional view of one raised portion of
the valve
body of Figure 2 illustrating a fluid control system for extending the
Figure 7 is an axial cross-sectional view of the control valve of Figure 2
as
taken along line 7-7.
Figure 8 is an axial cross-sectional view of the control valve of
Figure 2 as
taken along line 8-8.
Figure 9 is a cross sectional view of the valve of Figure 2 as taken
along
the line 3-3 showing a shifting tool located therein.
Figure 10 is an axial cross-sectional view of the shifting tool of
Figure 9 as
taken along the line 10-10.
Figure 11 a lengthwise cross sectional view of the shifting tool of
Figure 9
taken along the line 11-11 in Figure 10 with a control valve located
therein according to one embodiment with the sleeve engaging
members located at a first or retracted position.
Figure 12 is a cross sectional view of the shifting tool of Figure 9
taken along
the line 11-11 with a control valve located therein according to one
embodiment with the sleeve engaging members located at a
second or extended position
Figure 13 is a cross sectional view of a control valve according to a
further
embodiment for actuating the sleeve engaging members at a
closed position.
Figure 14 is a cross sectional view of a control valve according to a
further
embodiment for actuating the sleeve engaging members at an
open position.
Figure 15 is a schematic view of a system for controlling fluid flow
through a
wellbore.
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Figure 16 is a cross sectional view of a seal for use between tool
parts in a
wellbore.
Figure 17 is a perspective view of a shifting tool according to a
further
embodiment.
Figure 18 is a perspective view of a control valve according to a further
embodiment of the present invention.
Figure 19 is a cross sectional view of the control valve of Figure 18
as taken
along the line 19-19 with the sleeve in a first position.
Figure 20 is a cross sectional view of the control valve of Figure 18
as taken
along the line 19-19 with the sleeve in a second position and
having a shifting tool located therein.
Figure 21 is a cross sectional view of the control valve of Figure 18
as taken
along the line 19-19 with the sleeve in a third position.
Figure 22 is a detailed cross-sectional view of the ring and annular
grove of
the control valve of Figure 19.
Figure 23 is a cross sectional view of the filter section of the
control valve of
Figure 21 as taken along the line 23-23.
Figure 24 is a perspective view of a control valve according to a
further
embodiment of the present invention.
Figure 25 is a cross sectional view of the control valve of Figure 24 as
taken
along the line 25-25.
Figure 26 is a cross sectional view of the shifting tool illustrated in
Figure 20
as taken along the longitudinal axis of the valve body and shifting
tool.
Figure 27 is a cross sectional view of the shifting tool of Figure 26 as
taken
along the line 27-27.
Figure 28 is a cross sectional view of the shifting tool of Figure 26
as taken
along the line 28-28.
DETAILED DESCRIPTION
Referring to Figure 1, a wellbore 10 is drilled into the ground 8 to a
production
zone 6 by known methods. The production zone 6 may contain a horizontally
extending hydrocarbon bearing rock formation or may span a plurality of
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hydrocarbon bearing rock formations such that the wellbore 10 has a path
designed to cross or intersect each formation. As illustrated in Figure 1, the
wellbore includes a vertical section 12 having a valve assembly or Christmas
tree 14 at a top end thereof and a bottom or production section 16 which may
be horizontal or angularly oriented relative to the horizontal located within
the
production zone 6. After the wellbore 10 is drilled the production tubing 20
is
of the hydrocarbon well is formed of a plurality of alternating liner or
casing 22
sections and in line valve bodies 24 surrounded by a layer of cement 23
between the casing and the wellbore. The valve bodies 24 are adapted to
control fluid flow from the surrounding formation proximate to that valve body
and may be located at predetermined locations to correspond to a desired
production zone within the wellbore. In operation, between 8 and 100 valve
bodies may be utilized within a wellbore although it will be appreciated that
other quantities may be useful as well.
Turning now to Figure 2, a perspective view of one valve body 24 is
illustrated. The valve body 24 comprises a substantially elongate cylindrical
outer casing 26 extending between first and second ends 28 and 30,
respectively and having a central passage 32 therethrough. The first end 28
of the valve body is connected to adjacent liner or casing section 22 with an
internal threading in the first end 28. The second end 30 of the valve body is
connected to an adjacent casing section with external threading around the
second end 30. The valve body 24 further includes a central portion 34
having a plurality of raised sections 36 extending axially therealong with
passages 37 therebetween. As illustrated in the accompanying figures, the
valve body 24 has three raised sections although it will be appreciated that a
different number may also be utilized.
Each raised section 36 includes a port body 38 therein having an aperture 40
extending therethrough. The aperture 40 extends from the exterior to the
interior of the valve body and is adapted to provide a fluid passage between
the interior of the bottom section 16 and the wellbore 10 as will be further
described below. The aperture 40 may be filled with a sealing body (not
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shown) when installed within a bottom section 16. The sealing body serves to
assist in sealing the aperture until the formation is to be fractured and
therefore will have sufficient strength to remain within the aperture until
that
time and will also be sufficiently frangible so as to be fractured and removed
from the aperture during the fracking process. Additionally, the port bodies
38
are radially extendable from the valve body so as to engage an outer surface
thereof against the wellbore 10 so as to center the valve body 24 and thereby
the production section within the wellbore.
Turning now to Figure 3, a cross sectional view of the valve body 24 is
illustrated. The central passage 32 of the valve body includes a central
portion 42 corresponding to the location of the port bodies 38. The central
portion is substantially cylindrical and contains a sliding sleeve 44 therein.
The central portion 42 is defined between first or entrance and second or exit
raised portions or annular shoulders, 46 and 48, respectively. The sliding
sleeve 44 is longitudinally displaceable within the central portion 42 to
either
be adjacent to the first or second shoulder 46 or 48. At a location adjacent
to
the second shoulder, the sliding sleeve 44 sealably covers the apertures 40
so as to isolate the interior from the exterior of the bottom section 16 from
each other, whereas when the sliding sleeve 44 is adjacent to the first
shoulder 46, the sliding sleeve 44
The central portion 42 includes a first annular groove 50a therein proximate
to
the first shoulder 46. The sliding sleeve 44 includes a radially disposed snap
ring 52 therein corresponding to the groove 50a so as to engage therewith
and retain the sliding sleeve 44 proximate to the first shoulder 46 which is
an
open position for the valve body 24. The central portion 42 also includes a
second annular groove 50b therein proximate to the aperture 40 having a
similar profile to the first annular groove 50a. The snap ring 52 of the
sleeve
is receivable in either the first ore second annular groove 50a or 50b such
that
the sleeve is held in either an open position as illustrated in Figure 5 or a
closed position as illustrated in Figure 4. The sliding sleeve 44 also
includes
annular wiper seals 54 which will be described more fully below proximate to
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either end thereof to maintain a fluid tight seal between the sliding sleeve
and
the interior of the central portion 42.
The port bodies 38 are slidably received within the valve body 24 so as to be
radially extendable therefrom. As illustrated in Figure 3, the port bodies are
located in their retracted position such that an exterior surface 60 of the
port
bodies is aligned with an exterior surface 62 of the raised sections 36. Each
raised section may also include limit plates 64 located to each side of the
port
bodies 38 which overlap a portion of and retain pistons within the cylinders
as
are more fully described below.
Each raised section 36 includes at least one void region or cylinder 66
disposed radially therein. Each cylinder 66 includes a piston 68 therein which
is operably connected to a corresponding port body 38. Turning now to
Figures 4 and 5, detailed views of one port body 38 are illustrated at a
retracted and extended position, respectively. Each port body 38 may have
an opposed pair of pistons 68 associated therewith arranged to opposed
longitudinal sides of the valve body 24. It will be appreciated that other
quantities of pistons 68 may also be utilized for each port body 38 as well.
The pistons 68 are connected to the valve body by a top plate 70 having an
exterior surface 72. The exterior surface 72 is positioned to correspond to
the
exterior surface 62 of the raised sections 36 so as to present a substantially
continuous surface therewith when the port bodies 38 are in their retracted
positions. The exterior surface 72 also includes angled end portions 74 so as
to provide a ramp or inclined surface at each end of the port body 38 when
the port bodies 38 are in an extended position. This will assist in enabling
the
valve body to be longitudinally displaced within a wellbore 10 with the
vertical
section 12 under thermal expansion of the production string and thereby to
minimize any shear stresses on the port body 38.
The pistons 68 are radially moveable within the cylinders relative to a
central
axis of the valve body so as to be radially extendable therefrom. In the
extended position illustrated in Figure 5, the exterior surface 72 of the port
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bodies are adapted to be in contact with the wellbore 10 so as to extend the
port body 38 and thereby enable the wellbore 10 to be placed in fluidic
communication with the central portion 42 of the valve body 24. The pistons
68 may have a travel distance between their retracted positions and their
extended positions of between 0.10 and 0.50 inches although it will be
appreciated that other distances may also be possible. In the extended
position, it will be possible to f rack that location without having to also
fracture
the concrete which will be located between the valve body 24 and the
wellbore wall thereby reducing the required f rack pressure. Additionally,
more
than one port body 38 may be utilized and radially arranged around the valve
body so as to centre the valve body within the wellbore when the port bodies
are extended therefrom.
The pistons 68 may include seals 76 therearound so as to seal the piston
within the cylinders 66. Additionally, the port body 38 may include a port
sleeve 78 extending radially inward through a corresponding port bore 81
within the valve body. A seal 80 may be located between the port sleeve 78
and the port bore 81 so as to provide a fluid tight seal therebetween. A snap
ring 82 may be provided within the port bore 81 adapted to bear radially
inwardly upon the port sleeve 78. In the extended position, the snap ring 82
compresses radially inwardly to provide a shoulder upon which the port sleeve
78 may rest so as to prevent retraction of the port body 38 as illustrated in
Figure 5.
The pistons 68 may be displaceable within the cylinders 66 by the introduction
of a pressurized fluid into a bottom portion thereof. As illustrated in Figure
6,
a fluid control system is illustrated for providing a pressurized fluid to the
bottom portion of the cylinder 66 from the interior of the valve body 24. In
this
way a fluid pumped down the center of the bottom section 16 may be utilized
to extend the port bodies 38. The fluid control system comprises a fluid bore
90 extending longitudinally within the raised section 36 between an entrance
bore 94 and a pair of spaced apart piston connection bores 92. The piston
connection bores 92 intersect the bottom portion of the cylinders 66 while the
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entrance bore extends to the central passage 32 of the valve body 24. The
fluid bore 90 may include a relief check valve 96 located therein so as to
only
pressurize the cylinders 66 when a fluid of a sufficient pressure has been
pumped down the production string. In operation, a user may select a check
valve 96 of the desired actuation pressure which may be between 500 and
2000 pounds per square inch (psi) with a pressure of between 1000 and 1200
being particularly useful. Other pressures may also be selected which are
sufficient to centralize the valve body 24 within the wellbore. This pressure
may be referred to as an extension pressure. The fluid control system also
includes a relieve bore 98 extending from the fluid bore 90 to an exterior of
the valve body 24. As illustrated in Figure 8, the piston connection bores 92
may be formed by boring into the raised section 36 so as to intersect both the
fluid bore 90 and the cylinder 66 and thereafter filing the exterior portion
of the
piston connection bores with a piston connection plug 93 or the like.
The relief bore 98 includes a relief check valve 100 therein and is adapted to
relieve the pressure within the fluid control system and to ensure that the
pressure therein as well as within the bottom portion of the cylinders 66 does
not reach a pressure which may cause damage to apparatus. In particular, as
the extension pressure will be typically selected to be below the pressure
required to fracture the formation, or the frack pressure, it will be
necessary to
ensure that such a higher f rack pressure does not rupture the cylinder when
it
is applied to the interior of the bottom section 16. Frack pressures are known
to often be 10,000 psi or higher and therefore the relief check valve 100 may
be selected to have a opening pressure of between 5,000 and 8,000 psi.
With reference to Figure 3, the entrance bore 94 intersect the central passage
32 of the valve body 24. As illustrated each entrance bore 94 may be covered
by a knock-out plug 102 so as to seal the entrance bore until removed. In
operation, as concrete is pumped down the bottom section 16, it will be
followed by a plug so as to provide an end to the volume of concrete. The
plug is pressurized by a pumping fluid (such as water, by way of non-limiting
example) so as to force the concrete down the production string and
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thereafter to be extruded into the annulus between the horizontal section and
the wellbore. The knock-out plugs 102 are designed so as to be removed or
knocked-out of the entrance bore by the concrete plug passing thereby. In
such a way, once the concrete has passed the valve body 24, the concrete
plug removes the knock-out plugs 102 so as to pressurize the entrance bore
94 and fluid bore 90 and thereafter to extend the pistons 68 from the valve
body 24 once the pressurizing fluid has reached a sufficient pressure.
With reference to Figures 7 and 8, axial cross-sectional view of the valve
body
24 is illustrated through the center of the aperture 40 and port body 38 and
through the center of the pistons 68, respectively. Each raised section 36
includes a balancing bore 110 extending therealong substantially parallel to
the central axis of the valve body 24. The balancing bore 110 extending
between and entrance end 114 (shown on Figure 2) and a connection bore
112 extending to the port bore 81. The balancing bore 110 may include a
piston therein and be pre-filled with a fluid such as oil, by way of non-
limiting
example. In operation, the balancing bore 110 balances the pressure within
the bore port 81 as the port body 38 is extended from the valve body 24. In
particular, as the port body 38 is extended from the valve body, a negative
pressure will be created within the space between the closed sliding sleeve 44
and the sealing body (not shown) located within the aperture 40 as this space
is increased in volume. The balancing bore 110 reduces this negative
pressure by providing an additional fluid contained therein to be drawn into
the port bore 81 to fill this volume and balance the pressure therein with the
pressures to the exterior of the valve body 24. As illustrated in Figure 7,
the
connection bore 112 may be formed by boring into the raised section 36 so as
to intersect both the balancing bore 110 and the port bore 81 and thereafter
filing the exterior portion of the connection bore with a plug 116 or the
like.
Turning now to Figure 9, a shifting tool 200 is illustrated within the central
passage 32 of the valve body 24. The shifting tool 200 is adapted to engage
the sliding sleeve 44 and shift it between a closed position as illustrated in
Figure 9 and an open position in which the apertures 40 are uncovered by the
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sliding sleeve 44 so as to permit fluid flow between and interior and an
exterior of the valve body 24 as illustrated in Figure 5. The shifting tool
200
comprises a substantially cylindrical elongate tubular body 202 extending
between first and second ends 204 and 206, respectively. The shifting tool
200 includes a central bore 210 therethrough (shown in Figures 10 through
12) to receive an actuator or to permit the passage of fluids and other tools
therethrough. The shifting tool 200 includes at least one sleeve engaging
member 208 radially extendable from the tubular body 202 so as to be
selectably engageable with the sliding sleeve 44 of the valve body 24. As
illustrated in the accompanying figures, three sleeve engaging members 208
are illustrated although it will be appreciated that other quantities may be
useful as well.
The sleeve engaging members 208 comprise elongate members extending
substantially parallel to a central axis 209 of the shifting tool between
first and
second ends 212 and 214, respectively. The first and second ends 212 and
214 include first and second catches 216 and 218, respectively for
surrounding the sliding sleeve and engaging a corresponding first or second
end 43 or 45, respectively of the sliding sleeve 44 depending upon which
direction the shifting tool 200 is displaced within the valve body 24. As
illustrated in Figures 11 and 12, the first and second catches 216 and 218 of
the sleeve engaging member 208 each include and inclined surface 220 and
222, respectively facing in opposed directions from each other. The inclined
surfaces 220 and 222 are adapted to engage upon either the first or second
annular shoulder 46 or 48 of the valve body as the shifting tool 200 is pulled
or pushed there into. The first or second annular shoulders 46 or 48 press the
first or second inclined surface 220 or 222 radially inwardly so as to press
the
sleeve engaging members 208 inwardly and thereby to disengage the sleeve
engaging members 208 from the sliding sleeve 44 when the sliding sleeve 44
has been shifted to a desired position proximate to one of the annular
shoulders. In an optional embodiment, one or both of the catches 216 or 218
may have an extended length as illustrated in Figure 17 such that the sleeve
engaging members are disengaged from the sliding sleeve at a position
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spaced apart from one of the first or second annular shoulders 46 or 48 and
thereby adapted to position the sliding sleeve at a third or central position
within the valve body 24.
Turning to Figure 10, the sleeve engaging members are maintained parallel to
the tubular body 202 of the shifting tool 200 by a parallel shaft 230. Each
parallel shaft 230 is linked to a sleeve engaging member 208 by a pair of
spaced apart linking arms 232. The parallel shaft 230 is rotatably supported
within the shifting tool tubular body 202 by bearings or the like. The linking
arms 232 are fixedly attached to the parallel shaft 230 at a proximate end and
are received within a blind bore 234 of the sleeve engaging members 208. As
illustrated in Figure 9, the linking arms 232 are longitudinally spaced apart
from each other along the parallel shaft 230 and the sleeve engaging member
208 so as to be proximate to the first and second ends 212 and 214 of the
sleeve engaging member 208.
Turning now to Figure 11, the tubular body 202 of the shifting tool includes a
shifting bore 226 therein at a location corresponding to each sleeve engaging
member. The shifting bore 226 extends from a cavity receiving the sleeve
engaging member to the central bore 210 of the shifting tool 200. Each
sleeve engaging member 208 includes a piston 224 extending radially
therefrom which is received within the shifting bore 226. In operation, a
fluid
pressure applied to the central bore 210 of the shifting tool will be applied
to
the piston 224 so as to extend the piston within the shifting bore 226 and
thereby to extend the sleeve engaging members 208 from a first or retracted
position within the shifting tool tubular body 202 as illustrated in Figure 11
to a
second or extended position for engagement on the sliding sleeve 44 as
discussed above as illustrated in Figure 12. The parallel shafts also include
helical springs (not shown) thereon to bias the sleeve engaging members to
the retracted position.
The first end 204 of the shifting tool 200 includes an internal threading 236
therein for connection to the external threading of the end of a production
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string or pipe (not shown). The second end 206 of the shifting tool 200
includes external threading 238 for connection to internal threading of a
downstream productions string or further tools, such as by way of non-limiting
example a control valve as will be discussed below. An end cap 240 may be
located over the external threading 238 when such a downstream connection
is not utilized.
With reference to Figures 11 and 12, a first control valve 300 according to a
first embodiment located within a shifting tool 200 for use in wells having
low
hydrocarbon production flow rates. The low flow control valve 300 comprises
a valve housing 302 having a valve passage 304 therethrough and seals 344
therearound for sealing the valve housing 302 within the shifting tool 200.
The low flow control valve 300 includes a central housing extension 306
extending axially within the valve passage 304 and a spring housing portion
320 downstream of the central portion 310. The central housing extension
306 includes an end cap 308 separating an entrance end of the valve
passage from a central portion 310 of the valve passage and an inlet bore 322
permitting a fluid to enter the central portion 310 from the valve passage
304.
The central portion 310 of the valve passage contains a valve piston rod 312
slidably located therein. The valve piston rod 312 includes leading and
trailing
pistons, 314 and 316, respectively thereon in sealed sliding contact with the
central portion 310 of the valve passage. The leading piston 314 forms a first
chamber 313 with the end cap 308 having an inlet port 315 extending through
the leading piston 314. The valve piston rod 312 also includes a leading
extension 318 having an end surface 321 extending from an upstream end
thereof and extending through the end cap 308. The valve piston rod 312 is
slidable within the central portion 310 between a closed position as
illustrated
in Figure 11 and an open position as illustrated in Figure 12. In the closed
position, the second or trailing piston 316 is sealable against the end of the
central portion 310 to close or seal the end of the central passage and
thereby
prevent the flow of a fluid through the control valve. In the open position as
illustrated in Figure 12, the trailing piston 316 is disengagable from the end
of
CA 02809804 2013-03-18
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the central portion 310 so as to provide a path of flow, generally indicated
at
319, therethrough from the central passage to the spring housing.
A spring 324 is located within the spring housing 320 and extends from the
valve piston rod 312 to an orifice plate 326 at a downstream end of the spring
housing 320. The spring 324 biases the valve piston rod 312 towards the
closed position as illustrated in Figure 11. Shims or the like may be provided
between the spring 324 and the orifice plate 326 so as to adjust the force
exerted by the spring upon the valve piston rod 312. In other embodiments,
the orifice plate may be axially moveable within the valve body by threading
or
the like to adjust the force exerted by the spring. In operation, fluid pumped
down the production string to the valve passage 304 passes through the inlet
bore and into the central portion 310. The pressure of the fluid within the
central portion 310 is balanced upon the opposed faces of leading and trailing
pistons 314 and 316 such that the net pressure exerted upon the valve piston
rod 312 is provided by the pressure exerted on the end surface 321 of the
leading extension 318 and on the leading piston 314 from within the first
chamber 313. The resulting force exerted upon the end surface 321 is
resisted by the biasing force provided by the spring 324 as described above.
Additionally, the orifice plate 326 includes an orifice 328 therethrough
selected
to provide a pressure differential thereacross under a desired fluid flow
rate.
In this way, when the fluid is flowing through the central portion 310 and the
spring housing 320, the spring housing 320 will have a pressure developed
therein due to the orifice plate. This pressure developed within the spring
housing 320 will be transmitted through apertures 330 within the spring
housing to a sealed region 332 around the spring housing proximate to the
shifting bore 226 of the shifting tool 200. This pressure serves to extend the
pistons 224 within the shifting bores 226 and thereby to extend the sleeve
engaging members 208 from the shifting tool. The pressure developed within
the spring housing 320 also resists the opening of the valve piston rod 312
such that in order for the valve to open and remain open, the pressure applied
to the entrance of the valve passage 304 is required to overcome both the
CA 02809804 2013-03-18
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biasing force of the spring 324 and the pressure created within the spring
housing 320 by the orifice 328.
The valve 300 may be closed by reducing the pressure of the supplied fluid to
below the pressure required to overcome the spring 324 and the pressured
created by the orifice 328 such that the spring is permitted to close the
valve
300 by returning the valve piston rod 312 to the closed position as illustrate
in
11 as well as permitting the springs on the parallel shaft 230 to retract the
sleeve engaging members 208 as the pressure within the spring housing 320
is reduced. Seals 336 as further described below may also be utilized to seal
the contact between the spring housing 320 and the interior of the central
bore 210 of the shifting tool 200.
A shear sleeve 340 may be secured to the outer surface of the valve housing
302 by shear screws 342 or the like. The sheer sleeve 340 is sized and
selected to be retained between a pipe threaded into the internal threading
236 of the shifting tool 200 and the remainder of the shifting tool body. In
such a way, should the valve be required to be retrieved, a spherical object
334, such as a steel ball, such as are commonly known in the art may be
dropped down the production string so as to obstruct the valve passage 304
of the valve 300. Obstructing the flow of a fluid through the valve passage
304 will cause a pressure to develop above the valve so as to shear the shear
screws 342 and force the valve through the shifting tool. The strength of the
sheer screws 342 may be selected so as to prevent their being sheered
during normal operation of the valve 300 such as for pressures of between
1000 and 3000 psi inlet fluid pressure. The valve illustrated in Figures 11
and
12 is adapted for use in a low hydrocarbon flow rate well. In such well types,
the flow of fluids such as hydrocarbons or other fluids is low enough that the
fluid pumped down the well to pressurize the central portion 310 is sufficient
to overcome the flow of the fluids up the well so as to pass through the
orifice
328. It will be appreciated that for wells of higher well pressure or flow
rates,
such a valve will be limited in its application.
CA 02809804 2013-03-18
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Turning now to Figures 13 and 14, a second control valve 400 according to a
further embodiment located for use in wells having high hydrocarbon
production flow rates is illustrated. The high flow control valve 400
comprises
an outer tubular body 402 extending between first and second ends 404 and
406, respectively. An inner tubular body 408 is located within the outer
tubular body 402 having a central passage 410 therethrough and forming an
annular cavity 412 with the outer tubular body. A flap 420 is pivotally
connected to a distal end of the inner tubular body 408. The flap 420
selectably closes and seals the central passage 410 as the flap 420 is rotated
into a first or closed position as illustrated in Figure 13. The flap 420 may
also
be rotated to a second or open position as illustrated in Figure 14 so as to
permit fluids and tools to be passed through second control valve 400.
An elongate longitudinally displaceable sleeve 414 is received within the
annular cavity 412. The sleeve 414 includes an annular piston 416 at a first
end and a free second end 418. The second end 418 is connected to the flap
420 by a linkage 422 such that when flap 420 is rotated to the open position
as illustrated in Figure 14, the sleeve will be extended towards the second
end 406 of the control valve 400. Similarly, when the flap 420 is rotated to
the
closed position as illustrated in Figure 13, the sleeve 414 is retracted
towards
the first end 404.
The annular piston 416 is located within a first end 424 of the annular cavity
412 proximate to the first end 404 of the valve 400. The first end 424 is in
fluidic communication with an annulus around the exterior of the outer tubular
body 402 and also the distal end of the control valve 400 through a bore hole
426. The annular sleeve 414 is approximately hydrostatically balanced due to
the same pressurized fluid from the wellbore being present at the second end
418 of the sleeve as well as upon the annular piston 416 within the first end
424. Biasing the annular piston 416 towards the first end of the control valve
400 is a spring 430 contained within a spring cavity 428 between the annular
sleeve 414 and the outer tubular body 402. Additionally a spring cavity 428
may include an internal bore 432 from the central passage 410 so as to port
CA 02809804 2013-03-18
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or introduce a fluid into the spring cavity 428 and thereby prevent any fluid
contained therein from acting as a further biasing spring. The force exerted
upon the annular piston 416 may be adjusted by providing one or more shims
434 at an opposite end of the spring from the annular piston 416.
In a free resting state, the spring 430 biases the piston towards the first
end
404 of the control valve and thereby maintains the flap 420 in the closed
position. The flap 420 may be opened by pumping a fluid down the
production string so as to introduce a pressurized fluid into the central
passage thereof. The pressurized fluid forces the flap 420 open as illustrated
in Figure 14 when the flow and pressure of the pressurized fluid is sufficient
to
overcome the force of the spring 430.
The flap 420 may optionally include a check valve 436 therein comprising a
plug 438 compressed into the flap 420 by a spring 440 or the like. When a
closed flap 420 experiences a pressure from the bottom of the well greater
than the set point of the check valve, the well pressure will displace the
plug
438 against the spring 440 in a direction generally indicated at 442 in Figure
13. This will then open the check valve and permit fluid to flow past the
check
valve in direction 442. The central passage 410 of the valve also includes
internal threading 444 adapted to be threadably secured to the external
threading 238 of a shifting tool as described above. In such a connection, it
will be appreciated that the end cap 240 of the sleeve engaging member must
be removed to permit access to the external threading 238.
In operation, the control valve 400 actuates the sleeve engaging members of
the shifting tool by providing a pressurized fluid to the common passage
through the shifting tool 200 and the valve 400. When the central passage is
pressurized to a sufficient pressure by a fluid pumped down the production
string, the fluid from the central passage forces the flap 420 open.
Thereafter,
the fluid will need to be pumped down the production string at a sufficiently
high volume so as to maintain the pressure within the production string at a
CA 02809804 2013-03-18
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pressure sufficient to act upon the pistons 224 so as to extend the sleeve
engaging members 208.
Turning now to Figure 15, a schematic view of a system according to the
present invention is illustrated. The system may include one or more valve
bodies 24 located within a bottom section 16 as described above. In
operation, a user may extend a shifting tool 200 down the bottom section to
shift the sliding sleeve 44 at the end of a production casing 21. The shifting
tool 200 may be actuated by either the first valve 300 which is located within
the shifting tool 200 or by the second valve 400 which is located to a distal
end of the shifting tool.
With reference to Figure 16, one or more of the seals 460 for use with the
above system may comprise first and second spaced apart grooves 450 and
452, respectively. The first groove is sized to receive a wiper 454, such as a
radially compressible ring having a gap therein as are commonly known in the
art. As illustrated, the wiper 454 may have an uncompressed radius greater
than the radius of the first groove 450 so as to provide a radial space into
which the wiper may be compressed. The second groove is sized to receive
a vulcanized rubber seal 456 therein such that a gap, generally indicated at
458 is left between the seal 456 and the sides of the second groove 452. The
top of the seal 456 may be domed such that as the seal encounters an
opposed surface (not shown) the seal is pressed down into the second groove
to fill the gaps 458. The gaps 458 may have a distance of between 0.010 and
0.50 inches although it will be appreciated that other gap distances may be
used as well. When the seal encounters a space in the opposed surfaces,
such as for example at a port or the like the seal is permitted to expand to
it's
uncompressed shape to limit the volume of fluid which may be permitted to
pass into the port.
Turning now to Figures 18 through 21 a perspective view of a valve body 500
according to a further embodiment of the present invention is illustrated. The
valve body 500 comprises a substantially elongate cylindrical outer casing
CA 02809804 2013-03-18
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502 extending between first and second ends 504 and 506, respectively and
having a central passage 508 extending therethrough along an axis 509
between the first and second ends 504 and 506. The first end 504 of the
valve body is connected to adjacent liner or casing section 22 with internal
or
external threading 510 in the first end 504. The second end 506 of the valve
body 502 is connected to an adjacent filter section with internal threading
(as
illustrated in Figure 19) within the second end 506. The valve body 500
further includes first and second sets of ports, 512 and 514, respectively
therethrough (only the first set of ports 512 illustrated in Figure 18).
The second set of ports 514 may be formed by an insert 540 located within
bores 542 through the wall of the valve body. The inserts 540 may have
throttling bores 544 therethrough selected to maintain a desired pressure
across the second set of ports 514. The valve body 500 may include an outer
sleeve 550 extending therearound so as to enclose the second set of ports
514 to the second end 506 of the valve body 500 and form an annular cavity
552 therebetween. As illustrated in Figures 19 through 21, the second end
506 of the valve body 500 includes a plurality of transfer bores 554
therethrough between the outer and inner surfaces of the valve body 500.
As illustrated in Figures 19 through 21, the valve body may further include a
filter section 560 secured to the second end 504 of the valve body 500. The
filter section 560 is formed by an inner tubular body 562 secured to the inner
surface of the valve body 500 closer towards the first end 504 from the
transfer bores 554. The filter section further includes an outer tubular
screen
564 extending from the second end 506 of the valve body 500 with a filter
media 566 therebetween. The filter media may be of any suitable filter type,
such as, by way of non-limiting example, a slotted pipe, perforated pipe, wire
wrapped sleeve, pre-packed screens, MeshRiteTM or FracRiteTM. The outer
tubular screen 564 may be perforated or include a plurality of bores 568
therethrough. As illustrated in Figure 23, the inner tubular body 562 may
include a plurality of longitudinal slots 570 on the outer surface thereof
extending to the transfer bores 554. In operation,
fracking fluids or
CA 02809804 2013-03-18
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hydrocarbons are permitted to flow through the bores 568 and the filter media
566 so as to filter, screen or otherwise remove particles while permitting the
fluid to be collected within the slots 570 and thereafter directed to the
second
set of ports 514 through the transfer bores 554 and annular cavity 552.
As illustrated in Figure 19, the valve body 500 includes a longitudinally
moveable sleeve 530 which may be positioned so as to block the flow of fluids
though the first and second sets of ports 512 and 514. The sleeve 530
includes a radially expandable ring 532 therearound. An interior surface 515
of the valve body includes first, second and third annular grooves 516, 518
and 520, each sized to receive the ring 532 therein. The locations of the
first,
second and third annular grooves 516, 518 and 520 correspond to locations
at which sleeve may be positioned to either block one or both of the first or
second sets of ports. Optionally, the valve body 500 may include only one set
of ports 512 wherein the sleeve 530 may be slidable moved between first and
second positions to block and unblock the ports 512.
With reference to Figure 22, the sleeve 530 includes an annular groove 534
therein sized to receive the ring 532. A radially biasing spring 536 is
located
below the ring 532 within the groove 534 so as to bias the ring in a radially
outward direction. Examples of such springs may be a wave spring
manufactured by Smalley Steel Ring Company. The annular grooves 516,
518 and 520 may be formed with a substantially flat bottom portion surface
522 with angularly oriented walls 524 to either side thereof. The ring 532 may
be formed with so as to substantially conform to the shape of the annular
grooves. It will be appreciated that during movement from one position to
another, the angularly oriented walls 524 bear against the ring 532 so as
radially compress the ring inwards when a sufficient longitudinal force is
applied to the tools string. The strength of the spring 536 may be selected to
provide a force sufficient to prevent unwanted movement of the sleeve out of
the groove in which it is located. Such displacing force may be selected to be
between 500 and 15,000 pounds-force. It will also be appreciated that when
such a sufficient force has been applied to dislodge the sleeve from an
CA 02809804 2013-03-18
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annular groove, the resulting rapid movement of the shifting tool and sleeve
will cause a pressure surge in any fluids located within the well. Such a
pressure surge may be detected and measured by conventional means to
indicate to an operator that the sleeve has been dislodged from the groove.
As illustrated in Figure 19, the sleeve 530 may be located such that the ring
532 is located within the second annular groove 518. In such a position, both
of the first and second sets of ports 512 and 514 will be closed and no fluids
are permitted to flow into or out of the valve. In such a position, the zone
corresponding to this valve will be closed. As illustrated in Figure 20, the
sleeve 530 may be located such that the ring 532 is located within the third
annular groove 520. In such a position, the first set of ports 521 will be
open
and the second set of ports 514 will be closed. Such a position may be useful
for fracking the zone corresponding to such a valve wherein the fracking fluid
is permitted to flow through the first set of ports 512 in a direction
generally
indicated at 574. As illustrated in Figure 21, the sleeve 530 may be
positioned such that the ring 532 is located within the first annular groove
516
such that the first set of ports 512 is blocked while the second set of ports
514
is uncovered. In such a position, fluids are permitted to flow through the
screen 564 and filter media 566 into the slots 570 in a direction generally
indicated at 576. Thereafter the filtered fluid is collected through the
transfer
ports 554 in a direction generally indicated at 578 and through the second set
of ports 514 in a direction generally indicated at 580. Such a configuration
may be useful for collection of fracking fluids or during production of that
zone.
Turning now to Figures 24 and 25, an optional embodiment of the present
invention is illustrated having fluid injection jet ports. The valve body 500
may
include a plurality of protrusion bodies 590 extending therefrom having the
first set of ports 512 located therebetween. As illustrated in Figure 25, the
protrusion bodies 590 have the second set of ports 514 therein which have an
angular tube extending therefrom to an enlarged portion 594. The enlarged
portion 594 may house a nozzle body 596, plug or other body therein. The
CA 02809804 2013-03-18
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nozzle body 596 may include a nozzle 598 therethrough for directing
pressurized fluid into the well.
As set out above, the sleeve 530 may be located such that the ring 532 is
located within the second annular groove 518 as illustrated in Figure 25 so as
to close both the first and second sets of ports 512 and 514 whereby no fluids
are permitted to flow into or out of the valve. In such a position, the zone
corresponding to this valve will be closed. The sleeve 530 may also be
positioned such that the ring 532 is located within the first annular groove
516
such that the first set of ports 512 is blocked while the second set of ports
514
is uncovered. In such a position, fluids are permitted to flow through the
screen second set of ports and thereby be ejected by the nozzles 596 so as to
provide a stimulation or cleaning fluid to the well. The sleeve 530 may also
be
located such that the ring 532 is located within the third annular groove 520
so
as to open the first set of ports 512 and thereby relieve or collect fluids
from
the well bore.
Turning now to Figures 26 through 28, an sealed shifting tool 600 is
illustrated. As illustrated in Figures 26 and 27, the sealed shifting tool 600
comprises a tubular body 602 having no openings therethrough which are not
sealed as will be more fully described below to prevent any entrapment of
fluids or particulates therein. Similar to the shifting tool 200 described
above,
the sealed shifting tool tubular body 602 extending between first and second
ends 604 and 606, respectively. The shifting tool 600 includes a central bore
210 therethrough to receive an actuator or to permit the passage of fluids and
other tools therethrough.
The sealed shifting tool 600 includes at least one pair of sleeve engaging key
pistons 608 located within radial key bores 611. Each pair of key pistons 208
are aligned along a longitudinal direction of the sealed shifting key and each
include a lip 614 oriented towards each other for catching on a sleeve valve
44 and an inclined surface 616 oriented away from each other for surrounding
the sliding sleeve and engaging a corresponding first or second end 43 or 45,
CA 02809804 2013-03-18
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respectively of the sliding sleeve 44 depending upon which direction the
shifting tool 600 is displaced within the valve body 24 as set out above. The
inclined surfaces 616 are adapted to engage upon either a shoulder 46 or 48
of the valve body as the shifting tool 600 is pulled or pushed there into so
as
to press the inclined surface 616 radially inwardly so as to press the sleeve
engaging members 608 inwardly and thereby to disengage the sleeve
engaging members 608 from the sliding sleeve 44 when the sliding sleeve 44
has been shifted to a desired position proximate to one of the annular
shoulders. As illustrated, each key piston 608 and its corresponding key bore
611 may be have a circular cross section, although it will be appreciated that
other shapes may be useful as well, such as, by way of non-limiting example,
oval, square, rectagonal, triangular or irregular. As illustrated in Figure
28,
each key piston 608 is slidably sealed within its key bore 211 by a slidable
seal 612 as are known.
Similar to the shifting tool 200 above, each pair of key pistons 608 are
maintained parallel to the tubular body 602 of the shifting tool 600 by a
parallel shaft 230. Each parallel shaft 230 is linked to a sleeve engaging
member 208 by a pair of spaced apart linking arms 232. The parallel shaft
230 is rotatably supported within the shifting tool tubular body 602 by a
linkage 618, bearings or the like. The linking arms 232 are fixedly attached
to
the parallel shaft 230 at a proximate end and to a piston pins 620 at distal
ends thereof. The piston pins 620 extend through the distal ends of the
linking arms 232 as well as the key pistons 608 so as to fix the motion of
each
key piston 608 to each other. It will be appreciated that maintaining the key
pistons 608 parallel to each other to not catch on any other obstructions that
could be in the well
Similar to the shifting tool 200 above, the sealed shifting tool 600 includes
a
shifting bore 226 therein at a location corresponding to each pair of piston
keys 608 which includes a piston 224 extending radially therefrom which is
received within the shifting bore 226. Each piston 224 includes a piston cap
630 thereover which extends longitudinally to each side of the piston 224.
CA 02809804 2013-03-18
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The piston pins 620 extend into and are engaged within the piston cap 630 so
as to translate the movements of the piston 224 to each key piston 608. As
illustrated in Figure 26, the sealed shifting tool 600 also includes balancing
springs 632 located between the piston cap 630 and adjusting caps 634. The
adjusting caps 634 may be threadably moved radially inwards or outwards to
adjust the biasing force on the piston cap 630. As set out above, the
balancing springs 632 bias the piston cap and thereby the piston 224 and
piston keys 608 to the retraced position.
As illustrated in Figure 26, each of the piston cap, parallel shaft, linking
arms
232, piston pins 620 and springs 632 are isolated sealed from the central bore
210 within a chamber 636. The chamber 636 is also sealed against the
entrance of any particles to prevent fouling of the components located
therein.
The chamber 636 may include one or more balancing bores 638 extending
between the chamber 636 and the exterior of the shifting tool to permit fluids
to pass between the chamber 636 and the tool exterior so as to fluidically
balance the chamber and the tool exterior. In such embodiments, the
balancing bore 638 will include a filter 640 to prevent the entrance of any
particles as are commonly known.
While specific embodiments of the invention have been described and
illustrated, such embodiments should be considered illustrative of the
invention only and not as limiting the invention as construed in accordance
with the accompanying claims.
