Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02918439 2016-01-21
IS14.9708-CA-NP
METHOD AND.APPARATUS FOR WELL COMPLETION
BACKGROUND:
1 Field
[0001] The present disclosure relates to well completion in general and
in
particular to a method and apparatus for operating a high pressure shifting
tool
within a well.
2 Description of Related Art
[0002] Hydrocarbon fluids such as oil and natural gas are obtained from a
subterranean geologic formation, referred to as a reservoir, by drilling a
well that
penetrates the hydrocarbon-bearing formation. Once a wellbore is drilled,
various forms of well completion components may be installed in order to
control
and enhance the efficiency of producing the various fluids from the reservoir.
[0003] Fracturing is used to increase permeability of subterranean
formations. A fracturing fluid is injected into the wellbore passing through
the
subterranean formation. A propping agent (proppant) is injected into the
fracture
to prevent fracture closing and, thereby, to provide improved extraction of
extractive fluids, such as oil, gas or water.
[0004] One difficulty that may be encountered in some fracturing
operations is that there me debris located within the wellbore which impedes
the
movement of the equipment necessary for the fracturing operation. In such
situations it may be conventionally necessary to remove the fracturing
equipment
from the hole and introduce a drill thereinto to clear the debris whereafter
the
fracturing operations may continue.
[0005] Improvements in completing these unconventional formations
would be welcome by the industry.
1
CA 02918439 2016-01-21
1S14.9708-CA-NP
SUMMARY: =
[0006] In embodiments the disclosure pertains to methods for completing
a well comprising completing at least a zone of a first well using a pin-point
fracturing technique without using a sealing element.
[0007] In embodiments, the disclosure relates to methods for completing a
well comprising cleaning out the wellbore and then fracturing the well without
having the tool coming out of the well.
[0008] In embodiments, the disclosure aims at completions tools
combining cleaning tool and fracturing tool on a same toolstring.
[0009] According to a further embodiment, there is disclosed an apparatus
for performing a well completion comprising a tool string slidably locatable
within
the well and a shifting tool slidably locatable within the sleeve at an end of
a tool
string the shifting tool having a central bore therethrough and keys operable
to be
extended from an outer surface of the shifting tool when the central bore is
supplied with the fluid above a predetermined pressure, the keys being
engagable upon the sleeve so as to permit the shifting tool to move the sleeve
longitudinally within the tubular body. The apparatus further comprises a
motor
located at a distal end of the tool string having a mill operably rotated
thereby
and means for selectably actuating one of the shifting tool or motor.
[0010] The means for selectably actuating one of the shifting tool or
motor
may be operable to actuate the shifting tool between a first fluid flow range
through the tool string. The means for selectably actuating one of the
shifting
tool or motor may be operable to actuate the shifting tool above a
predetermined
fluid flow rate. The predetermined fluid flow rate may be higher than the
first fluid
flow range.
[0011] According to a further embodiment, there is disclosed a method for
performing a well completion comprising locating a tool string into a well
having a
shifting tool and a motor operably rotating a mill at distal end thereof and
providing a fluid flow rate through the tool string to a first fluid flow
range to
2
CA 02918439 2016-01-21
1S14.9708-CA-NP
actuate the motor. The method further comprises increasing the fluid flow rate
above the first fluid flow range to deactivate the motor and increasing the
fluid
flow rate above the first fluid flow range and a predetermined fluid flow rate
to
activate the shifting tool.
BRIEF DESCRIPTION OF THE DRAWINGS:
[0012] Certain embodiments of the disclosure will hereafter be described
with reference to the accompanying drawings, wherein like reference numerals
denote like elements. It should be understood, however, that the accompanying
drawings illustrate only the various implementations described herein and are
not
meant to limit the scope of various technologies described herein. The
drawings
show and describe various embodiments of the current disclosure.
[0013] Figure1 is a cross-sectional view of a wellbore having a plurality
of
flow control valves according to a first embodiment of the present
disclosure located therealong.
[0014] Figure 2 is a cross sectional view of a control valves of for use in
the
system of Figure 1.
[0015] Figure 3 is a longitudinal cross-sectional view of the control valve
of
Figure 2 as taken along the line 3-3.
[0016] Figure 4 is a detailed cross-sectional view of the extendable ports
of
the valve of Figure 2 in a first or retracted position.
[0017] 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.
[0018] Figure 6 is a cross sectional view of the valve of Figure 2 as taken
along the line 3-3 showing a shifting tool located therein.
[0019] Figure 7 is an axial cross-sectional view of the shifting tool of
Figure
6 as taken along the line 7-7.
[0020] Figure 8 a lengthwise cross sectional view of the shifting tool of
Figure 6 taken along the line 8-8 in Figure 7 with a control valve
3
CA 02918439 2016-01-21
= 1S14.9708-CA-NP
located therein according to one embodiment with the sleeve
engaging members located at a first or retracted position.
= [0021] Figure 9 is a cross sectional view of the shifting tool of
Figure 6 taken
along the line 8-8 with a control valve located therein according to
one embodiment with the sleeve engaging members located at a
second or extended position
[0022] Figure 10 is a perspective view of a shifting tool according to
a further
embodiment.
[0023] Figure 11 exemplifies a possible bottom hole assembly envisaged
by
the present disclosure.
DETAILED DESCRIPTION:
[0024]
At the outset, it should be noted that in the development of any
such actual embodiment, numerous implementation¨specific decisions must be
made to achieve the developer's specific goals, such as compliance with system
related and business related constraints, which will vary from one
implementation
to another. Moreover, it will be appreciated that such a development effort
might
be complex and time consuming but would nevertheless be a routine undertaking
for those of ordinary skill in the art having the benefit of this disclosure.
In
addition, the composition used/disclosed herein can also comprise some
components other than those cited.
In the summary and this detailed
description, each numerical value should be read once as modified by the term
"about" (unless already expressly so modified), and then read again as not so
modified unless otherwise indicated in context. Also, in the summary and this
detailed description, it should be understood that a concentration range
listed or
described as being useful, suitable, or the like, is intended that any and
every
concentration within the range, including the end points, is to be considered
as
having been stated. For example, "a range of from 1 to 10" is to be read as
indicating each and every possible number along the continuum between about 1
and about 10. Thus, even if specific data points within the range, or even no
data points within the range, are explicitly identified or refer to only a few
specific,
4
CA 02918439 2016-01-21
= IS14.9708-CA-NP
it is to be understood that ,inventors appreciate and understand that any and
all
data points within the range are to be considered to have been specified, and
that inventors possessed knowledge of the entire range and all points within
the
range.
[0025] The statements made herein merely provide information
related to
the present disclosure and may not constitute prior art, and may describe some
embodiments illustrating the disclosure.
[0026] In the specification and appended claims; the terms
"connect",
"connection", "connected", "in connection with", and "connecting" are used to
mean "in direct connection with" or "in connection with via one or more
elements"; and the term "set" is used to mean "one element" or "more than one
element". Further, the terms "couple", "coupling", "coupled", "coupled
together",
and "coupled with" are used to mean "directly coupled together" or "coupled
together via one or more elements". As used herein, the terms "up" and "down",
"upper" and "lower", "upwardly" and downwardly", "upstream" and "downstream";
"above" and "below"; and other like terms indicating relative positions above
or
below a given point or element are used in this description to more clearly
describe some embodiments of the disclosure.
[0027] The disclosure pertains to methods of treating an
underground
formation penetrated by either vertical wells or wells having a substantially
horizontal section. Horizontal well in the present context may be interpreted
as
including a substantially horizontal portion, which may be cased or completed
open hole, wherein the fracture is transversely or longitudinally oriented and
thus
generally vertical or sloped with respect to horizontal. The following
disclosure
will be described using horizontal well but the methodology is equally
applicable
to vertical wells.
[0028] The industry has privileged, when it comes to hydraulic
fracturing,
what is known as being "plug-and-pert" technique. Horizontal wells may extend
CA 02918439 2016-01-21
IS14.9708-CA-NP
hundreds of meters away from the vertical section of the wellbore. Most of the
horizontal section of the well passes through the producing formation and are
completed in stages. The wellbore begins to deviate from vertical at the
kickoff
point, the beginning of the horizontal section is the heel and the farthest
extremity
of the well is the toe. Engineers perform the first perforating operation at
the toe,
followed by a fracturing treatment. Engineers then place a plug in the well
that
hydraulically isolates the newly fractured rock from the rest of the well. A
section
adjacent to the plug undergoes perforation, followed by another fracturing
treatment. This sequence is repeated many times until the horizontal section
is
stimulated from the toe back to the heel. Finally, a milling operation removes
the
plugs from the well and production commences.
[0029] The common practice in the art is to perforate 4-6 clusters, and
push a slickwater laden fluid at or above fracture pressure to create
fractures; it
is estimated that 30 to 60% of these perforations do not produce due to for
example screen out, geological constraint, etc., and thus for every 100
perforations in a wellbore, commonly only 30 to 70 of the conventional
perforations are useful for production.
[0030] To respond to that, some operations now involve what is known as
pin-point fracturing, which may be defined as the operation of pumping a fluid
above the fracturing pressure of the formation to be treated through a single
entry. The entry may be a perforation, a valve, a sleeve, or a sliding sleeve.
Generally, sliding sleeves in the closed position are fitted to the production
liner.
The production liner is placed in a hydrocarbon formation. An object is
introduced into the weRbore from surface, and the object is transported to the
target zone by the flow field or mechanically, for example using a wireline or
a
coiled tubing. When at the target location, the object is caught by the
sliding
sleeve and shifts the sleeve to the open position, alternatively the object is
catching the sleeve and opens it. A sealing device, such as a packer or cups,
is
positioned below the sleeve to be treated in order to isolate the lower
portion of
the wellbore. The sealing device is set, fluid is pumped into the fracture and
then
6
CA 02918439 2016-01-21
IS14.9708-CA-NP
the sealing device is unset and moved below the next zone (or sleeve) to be
treated. Representative examples of sleeve-based systems are disclosed in US
7,387,165, US 7,322,417, US 7,377,321, US 2007/0107908, US 2007/0044958,
US 2010/0209288, US 7,387,165, US2009/0084553, US 7,108,067, US
7,431,091, US 7,543,634, US 7,134,505, US 7,021,384, US 7,353,878, US
7,267,172, US 7,681,645, US 7,066,265, US 7,168,494, US 7,353,879, US
7,093,664, and US 7,210,533, which are hereby incorporated herein by
reference. A fracturing treatment is then circulated down the wellbore to the
formation adjacent the open sleeve.
[0031] Operations involving sliding sleeve imply to have a casing or
liner
that having pre-fitted or preinstalled sleeves when the well is cased thereby
prior
to cementing the well. Operators then typically need to clean the well in
order to
start the hydraulic stimulation; this is known in the industry as a clean out
run
which involves cleaning potential debris that may remain in the wellbore and
usually takes hours before the fracturing tools can be lowered down the well.
The present disclosure aims at optimizing such clean out by enabling to
combine
both the clean out run with the trip to lower the hydraulic stimulation tools.
[0032] Embodiments herein relate to methods of completing an
underground formation using multi-stage pin-point fracturing for treating a
well
without using any sealing element.
[0033] In embodiments, a cased-hole is provided with a production tubing
(or casing) fitted with sliding reclosable sleeves (as in Figure 1) at the
desired
location and quantity. After the completion (desired amount of sleeves and
casing) is installed into the well, the well would be set up for
fracture/stimulation
operations. Using, for example, a coil tubing or stick pipe an actuation
device
would be conveyed into the well.
[0034] The actuation device, indifferently mentioned here as shifting
tool,
may be a tool that is equipped with a sleeve engaging member selectably
7
CA 02918439 2016-01-21
1S14.9708-CA-NP
extendable from the shifting tool in parallel to a central axis of the
shifting tool
and engagable upon the sleeve wherein the shifting tool is moveable so as to
cause the sleeve to selectably cover and uncover the apertures. A suitable
combination sliding sleeve and shifting tool may be found in US2012/0125627
incorporated herein by reference in its entirety.
[0035] Referring to FIG. 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 hydrocarbon bearing rock formations such that the wellbore 10 has
a
path designed to cross or intersect each formation. As illustrated in FIG. 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.
[0036] Turning now to FIG. 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 thereth rough. 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
8
= CA 02918439 2016-01-21
= IS14.9708-CA-NP
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.
[0037] Each raised section 36 includes a radially movable body
or 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 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 fracing 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.
[0038] Turning now to FIG. 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
[0039] The central portion 42 includes a first annular groove
50 a therein
9
CA 02918439 2016-01-21
=
1S14.9708-CA-NP
proximate to the first shquIder 46. The sliding sleeve 44 includes a radially
disposed snap ring 52 therein corresponding to the groove 50 a 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 50 b therein proximate to the aperture 40 having a
similar
profile to the first annular groove 50 a. The snap ring 52 of the sleeve is
receivable in either the first or second annular groove 50 a or 50 b such that
the
sleeve is held in either an open position as illustrated in FIG. 5 or a closed
position as illustrated in FIG. 4. The sliding sleeve 44 also includes annular
wiper
seals 54 which will be described more fully below proximate to either end
thereof
to maintain a fluid tight seal between the sliding sleeve and the interior of
the
central portion 42.
[0040] The port bodies 38 are slidably received within the
valve body 24
so as to be radially extendable therefrom. As illustrated in FIG. 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.
[0041] 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 forming an actuator for
selectably moving the port bodies 38. Turning now to FIGS. 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
CA 02918439 2016-01-21
IS14.9708-CA-NP
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.
[0042] 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 FIG. 5, the exterior surface 72 of the port
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 frac
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
frac 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.
[0043] 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 FIG. 5. The pistons
68 may
11
CA 02918439 2016-01-21
1S14.9708-CA-NP
be displaceable within the cylinders 66 by the introduction of a pressurized
fluid
into a bottom portion thereof. It will also be appreciated that other sleeve
valves
may be utilized which do not include extendable pistons as illustrated herein
as
are commonly known in the art.
[0044] With reference to FIG. 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 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.
[0045] Turning now to FIG. 6, 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 FIG. 4 and an open position in which the apertures 40 are uncovered by the
sliding sleeve 44 so as to permit fluid flow between and interior and an
exterior of
the valve body 24 as illustrated in FIG. 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 FIGS. 7 through 9) 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
12
CA 02918439 2016-01-21
IS14.9708-CA-NP
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.
[0046] 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
FIGS. 8
and 9, 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 FIG. 10 such that the sleeve engaging members are disengaged from the
sliding sleeve at a position 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.
[0047] Turning to FIG. 7, 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
13
CA 02918439 2016-01-21
= IS14.9708-CA-NP
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 FIG. 6, 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.
[0048] Turning now to FIG. 8, 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 FIG. 8 to a second or extended
position for
engagement on the sliding sleeve 44 as discussed above as illustrated in FIG.
9.
The parallel shafts also include helical springs (not shown) thereon to bias
the
sleeve engaging members to the retracted position.
[0049] 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 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.
[0050] With reference to FIGS. 8 and 9, a first control valve
300 according
to a first embodiment located within a shifting tool 200 for use in wells
having low
14
CA 02918439 2016-01-21
1S14.9708-CA-NP
hydrocarbon production flpw 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.
[0051] 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
FIG. 8 and an open position as illustrated in FIG. 9. 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 FIG.
9, the
trailing piston 316 is disengagable from the end of 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.
[0052] 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 FIG. 8. Shims or the like may be provided
between the spring 324 and the orifice plate 326 so as to adjust the force
exerted
CA 02918439 2016-01-21
1S14.9708-CA-NP
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.
[0053] 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 biasing
force
of the spring 324 and the pressure created within the spring housing 320 by
the
orifice 328.
[0054] 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
16
CA 02918439 2016-01-21
1S14.9708-CA-NP
in 11 as well as permitting the wrings 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.
[0055] 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 FIGS. 8 and 9 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.
[0056] In embodiments, the method for completing a well involves an
apparatus for selectably opening a valve body in a well casing having a
central
passage and a plurality of apertures therethrough. The apparatus comprises a
sleeve slidably located within the central passage of the valve body adapted
to
selectably cover or uncover the apertures and a shifting tool slidably
locatable
within the sleeve. The apparatus further comprises at least one sleeve
engaging
17
CA 02918439 2016-01-21
IS14.9708-CA-NP
member selectably extendable fr9m the shifting tool in parallel to a central
axis of
the shifting tool and engagable upon the sleeve wherein the shifting tool is
moveable so as to cause the sleeve to selectably cover and uncover the
apertures.
[0057] The sleeve may be axially displaceable within the central passage.
The sleeve may be displacable between a first position covering the apertures
and a second position uncovering the apertures. The sleeve may seal the
apertures in the first position.
[0058] The shifting tool may be securable to the end of a production
casing nested within the well casing. The shifting tool may include a central
bore
therethrough. The central bore may include a plurality of shifting bores
extending
therefrom, each shifting bore having a piston therein operably connected to a
sleeve engaging member for extending the sleeve engaging member when the
central bore is supplied with a pressurized fluid.
[0059] The sleeve engaging members may comprise elongate members
extending between first and second ends. The sleeve engaging members may
extend parallel to an axis of the central bore. The first and second ends of
the
sleeve engaging members may include first and second catches for engaging
corresponding first and second ends of the sleeve. The first and second
catches
may be spaced apart by a distance sufficient or receive the sleeve
therebetween.
[0060] The first and second ends of the elongate members may include
corresponding first and second inclined surfaces. The central passage may
include a raised portion proximate to the first position of the sleeve so as
to be
engaged by the first inclined surface as the sleeve is moved into the first
position
and thereby to disengage the catches from the sleeve. The central passage may
include a raised portion proximate to the second position of the sleeve so as
to
be engaged by the second inclined surface as the sleeve is moved into second
first position and thereby to disengage the catches from the sleeve.
18
CA 02918439 2016-01-21
1S14.9708-CA-NP
[0061] Each
sleeve engaging member may include a shaft extending
therealong and at least two linking arms extending from the shaft to the
sleeve
engaging member so as to maintain the sleeve engaging member parallel
thereto. The linking arms may be received within sockets within the sleeve
engaging member.
[0062]
According to further embodiments, there is disclosed an apparatus
for shifting a sleeve of a sleeve valve, the sleeve valve comprising a valve
body
with at least one aperture extending therethrough and an axially displaceable
sleeve adapted to selectably cover or uncover the apertures. The apparatus
comprises a shifting tool slidably locatable within the sleeve and at least
one
sleeve engaging member selectably extendable from the shifting tool in
parallel a
central axis of the shifting tool and engagable upon the sleeve.
[0063]
According to further embodiments, there is disclosed a method for
selectably opening a valve body in a well casing having a central passage and
a
plurality of apertures therethrough. The method comprises providing a sleeve
slidably located within the central passage of the valve body adapted to
selectably cover or uncover the apertures. The sleeve is located in one of a
first
or second position. The method further comprises positioning an shifting tool
slidably locatable within the sleeve, extending the at least one sleeve
engaging
member selectably extendable from the shifting tool in parallel to a central
axis of
the shifting tool into engagement upon the sleeve, and axially moving the
shifting
tool and the sleeve to another of the first or second positions.
[0064] The
method may further comprise disengaging the at least one
sleeve engaging member from the sleeve at the other of the first or second
positions.
[0065]
According to further embodiments, there is disclosed a method for
actuating a sleeve valve, the sleeve valve comprising a valve body with at
least
one aperture extending therethrough and an axially displaceable sleeve adapted
19
CA 02918439 2016-01-21
1S14.9708-CA-NP
to selectably cover or uncover the apertures. The method comprises locating a
shifting tool within the sleeve, extending at least one sleeve engaging member
from the shifting tool until engaged upon the sleeve, axially moving the
shifting
tool and sleeve and retracting the sleeve engaging member until disengaged
from the sleeve.
[0066] According to further embodiments, there is disclosed a method for
applying a fluid actuation pressure to a portion of an actuator, the method
comprising sealably locating a valve body within the interior of the actuator,
the
valve body having an interior cavity therein and applying a fluid pressure to
an
upstream end of the valve body. The method further comprises slidably
displacing a piston within the interior cavity after the fluid pressure
reaches a
desired pressure so as to open a fluid path through the valve body and passing
the fluid through ports in an exterior of the valve body to provide the supply
pressure to the actuator.
[0067] According to further embodiments, there is disclosed an apparatus
for applying a fluid actuation pressure to a portion of an actuator comprising
a
valve body sealably locatable within the interior of the actuator, having an
interior
cavity. The valve body has a cylinder portion and a spring housing portion.
The
spring housing portion has a plurality of ports therethrough at a location
corresponding to the actuator. The apparatus further includes an entrance end
for applying a fluid pressure to an upstream end of the valve body and a rod
slidably locatable within the cylinder portion. The entrance end is in fluidic
communication with the cylinder portion. The rod has a piston sealed within
the
interior of the cylinder portion, the rod and piston displaceable to an
actuating
position wherein the piston is displaced out of the cylinder portion so as to
place
the entrance end in fluidic communication with the spring housing portion. The
apparatus further comprises a compression spring engaged against a
downstream portion of the rod and piston so as to bias the rod and piston into
a
closed position within the cylinder portion and an outlet orifice at a
downstream
end of the spring portion so as to release fluid from the spring housing at a
CA 02918439 2016-01-21
1S14.9708-CA-NP
desired rate.
[0068] According to further embodiments, there is disclosed a method for
applying a fluid actuation pressure to a portion of an actuator. The method
comprises sealably securing a valve body to a distal end of the actuator and
pumping a pressurized fluid through the valve body and actuator so as to
provide
an actuation pressure to the actuator.
[0069] According to further embodiments, there is disclosed a method for
opening a passage through a terminal end of a production string. The method
comprises providing a valve body at a distal end of the production string,
providing an actuation pressure to actuation fluid within the so as to open a
flap
at a distal end thereof. The flap being operably connected to an annular
piston
longitudinally displaceable within the valve body and being biased with a
spring
so as to bias the flap to a closed position.
[0070] According to further embodiments, there is disclosed an apparatus
for selectably sealing and pressurizing a production string. The apparatus
comprises a valve body connectable to a distal end of a production string, the
valve body having an interior cavity in fluidic communication with the
production
string and an annulus between the valve body and the well casing and a flapper
valve rotatably located at a distal end of the interior cavity at a distal end
of the
valve body. The apparatus further comprises a spring biased piston
longitudinally
displaceable within the valve body, the piston operatively connected to the
flapper valve so as to bias the flapper valve to a closed position and be
openable
when a fluid is pumped through the interior cavity.
[0071] In embodiments the string is supplemented with a cleaning
equipment, thus enabling to prepare the wellbore for stimulation and to begin
operation directly after cleaning. In the art, this type of operation would
have
imposed for example a coiled tubing lowering a first toolstring comprising a
mill
and motor, or other cleanout bottom hole assembly such as cleanout nozzle or
21
CA 02918439 2016-01-21
1S14.9708-CA-NP
Junk Basket, to assure well cleaning conditions prior to replacing the with
toolstring with a further toolstring comprising the completion equipment such
as a
shifting-tool to manipulate specific sleeves in the wellbore; once well is
ready, the
shifting tool would be run in the hole next.
[0072] The
current disclosure describes a bottom hole assembly enabling
such efficiency by combining a mill equipment with a motor and a shifting tool
for
actuating the sleeves installed in the casing. An exemplary embodiment
illustrated in Figure 11 where the bottom hole assembly 500 (also sometimes
referred to as tool string) comprise a connector or joint 502 to connect the
assembly to the conveyance mean which may be for example a coiled tubing.
Then optionally some centralizers 504 may be present. The bottom hole
assembly 500 may also include an optional mechanical disconnect mean 506
and/or a hydraulic disconnect mean 508 as are commonly known and an optional
circulation sub 510 followed by the shifting 200 equipment useful for
selectively
activating the sleeves in later operations as set out above. An orifice sub
512
may also present then the downhole motor 514 to empower the mill 516 which
will effectively destroy or drill potential remaining debris. The circulation
sub 510
may be optional, however, it offer at least another potential circulation path
for
the fluid which may be useful for example when the primary flow path becomes
blocked or obstructed; in such situation the circulation sub may be opened for
example by either flow or pressure to re-establish full circulation. In
embodiments, the circulation sub may also be used when a nitrogen lift, to
help
the well flow following the fracturing treatment, is needed. The circulation
sub
may be actuated to prevent pumping the nitrogen through the motor thus
extending the life of the motor.
[0073] In
embodiments, the motor is conveyed by coiled tubing or joint
pipe. The mill is driven by the motor which is actuated depending on the pump
rate used examples of suitable flow rate may be from 60 galUS/min to 119
galUS/min. The motor is actuated by flow rate, which creates relative rotation
between the rotor rolling in the inner wall of the stator. This eccentric
motion is
22
CA 02918439 2016-01-21
1S14.9708-CA-NP
translated to rotation by way of a flexshaft in the transmission section of
the
motor. This in turn powers the bit or mill below the motor. The flow rate
required
to actuate the motor is a function of the number of stages in the motor power
section (combination of rotor and stator), the lobe configuration of the motor
power section and the clearance between the rotor and inner wall of the stator
(referred to as 'fit'). The operator can choose to actuate the motor in order
to
rotate the mill while lowering down the tool or the mill might be rotated at
any
specific location where a sleeve should then be opened or the operator may
lower down the whole bottom hole assembly until encountering a restriction. In
the latter case, the operator would then actuate the motor in order to clean
the
restriction and then further continue the hydraulic fracturing by opening the
targeted sleeve.
[0074] In
embodiments, the shifting tool may be actuated at flow rate
superior to the flow rates suitable to actuate the motor. In embodiments the
shifting tool may be actuated at flow rates above 120 gal US/min, or above 130
gal US/min, or between 130 gal US/min and 160 gal US/min. These values may
be modified according to the well operating conditions. This may be achieved
with a circulation device, such as an annular circulation device, a multi-
cycle
circulation device, a tubing pressure circulation device, an inline universal
valve,
a ported sub or a burst disc (collectively referred to as a "circulation
device").
The circulation device may be located between the shifting tool and motor (513
in
Fig 11). During the cleanout operation, flow will be directed through the
motor,
actuating the motor without extending the shifting tool keys. When the flow
rate
is elevated above a predetermined value, the increased differential pressure
will
activate the circulation device, which will divert flow away from the motor,
to the
wellbore annulus. The rate can then be increased beyond the range of the motor
and allow full extension of the shifting tool keys for sleeve manipulation.
The
circulating device may or may not be resettable, depending on device used and
objectives. If device is resettable, flow to the motor may be restored upon
reduction of pump rate. If device is not resettable, flow path will continue
to the
23
CA 02918439 2016-01-21
1S14.9708-CA-NP
annulus, however shifting ,tool keys can be retracted with slight reduction in
flow
rate.
[0075] Fracturing operations could then start at any location in the
well; for
example from toe-to-heel, or from heel-to-toe or at any preferred location by
opening the sleeve corresponding to the chosen zone to be fracture; then, the
fluid pressure would be increased until reaching the fracturing pressure of
the
formation. The created fracture may then be propped with the fracturing fluid
and
when the operator decides to move to another zone, the activation device will
then be used to reclose the opened sleeve, thus isolating the treated zone.
This
will be repeated until the amount of targeted zone has been treated; at any
time if
a restriction is encountered, the mill might be used.
[0076] Accordingly, each zone may be fractured independently and then
isolated after the fracture is complete. The reclosing sleeve enables to
fracture
and isolate each specific zone without using any isolation (or sealing)
elements
such as packer, isolation plug, or cups. Combined with a cleaning equipment
(motor and mill); this would make the pin-point fracturing technique much more
efficient and reliable than the current techniques involving setting and
unsetting a
packer for each zone or even having to run a cleaning stage before initiating
any
fracturing operations. While taking into account that in many of past
fracturing
operations, the use of sealing elements such as packer have been the source of
problems, the currently disclosed methods alleviate questions about
reliability of
sealing element and one of the many further advantages is that it would also
not
require having a toe valve or opening to run in equipment. The sleeve is
reclosed
after fracture/stimulation to provide pressure integrity back to the casing
string.
This opens up the opportunity to fracture/stimulate the wellbore in any
fashion.
Then, by removing the sealing element, there will no longer needs to be a
washing step for cleaning the sealing elements thus reducing fluid
consumption,
suppressing overflush which will contribute to better fracturing jobs.
[0077] In embodiment, the actuation device is mounted on a coiled tubing
24
CA 02918439 2016-01-21
1S14.9708-CA-NP
element. The coiled tubing may remain in the wellbore during the
fracture/stimulation. Once all the zones are fractured / stimulated the coil
tubing
may be lowered to the toe of the well. During this time, the clean out of the
well
can be performed without having to change any part of the Bottom Hole
Assembly (BHA) to ensure all debris and sand are washed from the wellbore.
[0078] Once the cleanout is completed, the actuation device is put in
opening position and the coil tubing is pulled out of the well. The upward
motion
would open all the sleeves coming out of the well leaving the well clean and
ready for production.
[0079] While the present disclosure has been disclosed with respect to a
limited number of embodiments, those skilled in the art, having the benefit of
this
disclosure, will appreciate numerous modifications and variations there from.
It is
intended that the appended claims cover such modifications and variations as
fall
within the true spirit and scope of the disclosure.
