Note: Descriptions are shown in the official language in which they were submitted.
1
Regulating Flow and Controlling Water Acidification Well Completion
Device for Oil and Gas Well and Use Method Thereof
Technical Field
The invention belongs to the technical field of oil and gas well development,
relates to
segmented regulating flow and controlling water, segmented acid fracturing and
oil and gas
production technology of an oil and gas well, in particular relates to a
regulating flow and
controlling water acidification device suitable for an oil and gas well,
specifically a regulating
flow and controlling water acidification well completion device for an oil and
gas well and a use
method thereof.
Background
With the increasing energy demand in the world, the exploration of deep
complex natural
gas and tight oil and gas has increasingly become the focus of fossil energy
exploration and
development all over the world. However, when many complicated oil and gas
reservoirs are
developed, they often face the influence of acidic H2S and CO2 gas, and most
oil and gas wells
contain highly toxic H2S gas. In order to increase production per well and
reduce input-output
ratio, many deep oil and gas reservoirs are completed by long horizontal
wells. As oil and gas
wells are distributed by extending from a main block to peripheral blocks, the
physical properties
of the reservoir relatively become worse. In order to improve productivity per
well, the long
horizontal well typically requires acid fracturing and acid pickling
operations. Some blocks have
more than 1,000 meters of horizontal wellbore length. Due to permeability
anisotropy and rock
heterogeneity of the long horizontal wellbore, the effect of general acid
fracturing and acid
pickling is not obvious, so it is usually necessary to perform segmented acid
fracturing and acid
pickling operations to improve production per well.
At present, an integrated pipe string is usually produced by segmented acid
fracturing.
However, with the development of oil and gas fields into the middle and later
periods, the
increase of water production of the oil and gas wells and water production
stop from the oil and
gas wells due to flooding become more and more important to the production of
the whole
oilfield. Because the horizontal wellbore is long, after the integrated pipe
string is produced by
the segmented acid fracturing for a certain production time, because of rock
heterogeneity and
permeability anisotropy along the horizontal wellbore, different horizontal
well segments
produce different amounts of oil and gas. In addition, because the boundary
line of the oil and
gas reservoir outside a control area of the horizontal wellbore is relatively
complex, it is not
Date Recue/Date Received 2022-05-09
2
necessarily a straight line or a straight surface parallel to the horizontal
wellbore. Therefore,
when there is strong edge and bottom water around, once a certain horizontal
segment produces
water or is broken through by water, the whole horizontal wellbore will be
submerged by water
quickly, thus resulting in water blocking in the wellbore, oil and gas can not
be produced
smoothly, which will affect the productivity of the oil and gas wells. This
requires consideration
of segmented water control during the completion process. Because the deep
complex oil and
gas reservoirs are generally high in H2S, in order to prevent H2S accidents,
generally in the
completion process of the oil and gas wells, it is required to ensure that the
completion operation
is completed in one trip as much as possible after the heavy slurry kill fluid
is injected, and it is
not recommended to trip out the pipe string for multiple times, so as to
prevent H2S from spilling
over the wellhead from the well bottom and causing serious accidents.
Therefore, after
segmented acid fracturing, the operation modes such as tripping production and
water control
pipe string cannot be realized.
In order to efficiently develop complex deep acidic gas-containing oil and gas
reservoirs,
on the basis of the segmented acid fracturing, balanced gas production at
later stages is
considered, water control restrains edge and bottom water coning, and
meanwhile in
consideration of risk of high H2S content operation, there is a need for an
integrated pipe string
and matching process for acid fracturing production and water control
applicable to high H2S
content gas wells, to complete the well by running the integrated pipe string.
Only one trip of
pipe string is required for operation, and effective segmented acid fracturing
can make the
reservoir communicate and production can be achieved, and in the production
process, the water
can be effectively controlled by segments, the production speed of gas in
different segments can
be balanced, the coning speed of edge and bottom water outside the control
areas of different
segments can be suppressed, so as to realize the integration of acid
fracturing production and
water control in one-pass process, save the process cost and at the same time
ensure the
production safety of complex deep oil and gas wellbore to the maximum extent.
Summary of the Invention
In view of the above disadvantages, it is an object of the present invention
to provide a
regulating flow and controlling water acidification well completion device for
an oil and gas
well and a use method thereof, which overcome the problem that one trip of
pipe string can not
realize the integration of segmented acid fracturing and regulating flow and
controlling water,
by running a tool device and a pipe string system that integrate the segmented
acid fracturing
completion and the production and water control functions in one-pass
operation.
It is an object of the present invention to provide a regulating flow and
controlling water
Date Recue/Date Received 2022-05-09
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acidification well completion device for an oil and gas well, which realizes
the function of
performing production by the original pipe string after acid fracturing by
running the pipe string
in one trip, and has the effect of controlling water and inhibiting edge and
bottom water coning
of the oil and gas wells, in this way, the low-water-content production period
of the oil and gas
well is prolonged, the recovery efficiency of the oil and gas well is
improved, and the purposes
of reducing the operation procedure and saving the process cost are achieved.
Another object of the present invention is to provide a regulating flow and
controlling water
acidification well completion device for an oil and gas well, so as to prevent
the production of
corrosive gas in the completion process to the maximum extent, ensure the
safety of production
operation, realize the goal of the maximum recovery degree in the control area
of complex
horizontal oil and gas wells with high hydrogen sulfide content, and then
realize the completion
and production optimization of the deep complex oil and gas wells.
To achieve at least one of the above objects, the present application adopts
the following
technical solution:
a regulating flow and controlling water acidification well completion device,
comprising:
a regulating flow and controlling water sieve pipe, having a base pipe, a
sieve mesh portion
disposed on the base pipe and a regulating flow and controlling water portion
in communication
with the sieve mesh portion, wherein the sieve mesh portion is used to filter
formation fluid, the
regulating flow and controlling water portion is connected downstream of the
sieve mesh
portion, for increasing the flow resistance of water in the formation fluid;
a single flow mechanism connected to the regulating flow and controlling water
sieve pipe,
in which a central passage communicating with the base pipe and an acidifying
hole
communicating the central passage with the outside of the single flow
mechanism are provided,
wherein the single flow mechanism is configured to operatively open and close
the acidifying
hole by off-well impaction.
As a preferred embodiment, the base pipe is further provided with a
unidirectional
component which is configured to allow fluid to flow from the sieve mesh
portion to the
regulating flow and controlling water portion, while preventing the fluid from
flowing from the
regulating flow and controlling water portion to the sieve mesh portion.
As a preferred embodiment, the sieve mesh portion includes an outer protection
sheath, a
filter screen, a flow guiding mesh, a filter screen, a flow guiding mesh and a
supporting layer
which are sleeved in order from the outside to the inside, wherein circular
through holes are
distributed on the outer protection sheath, the flow guiding mesh is used for
guiding the fluid,
the filter screen, the flow guiding mesh and the supporting layer are
integrally fixed by extrusion
Date Recue/Date Received 2022-05-09
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forging.
As a preferred embodiment, the regulating flow and controlling water portion
includes an
outer pipe fixed to the outer side of the base pipe, and a regulating flow and
controlling water
member mounted on the wall of the base pipe inside the outer pipe, a
regulating flow and
controlling water space is formed between the base pipe and the outer pipe,
and the regulating
flow and controlling water member communicates the interior of the base pipe
with the
regulating flow and controlling water space.
As a preferred embodiment, the regulating flow and controlling water sieve
pipe is a single
flow controlling water sieve pipe, wherein the unidirectional component
includes:
an overflowing sleeve fixedly arranged inside the outer pipe, wherein the
overflowing
sleeve separates the regulating flow and controlling water space radially to
form an inner space
and an outer space that is connected to the sieve mesh portion, the regulating
flow and controlling
water member communicates the inner space with the inside of the base pipe,
and the
overflowing sleeve is provided with a communication hole which communicates
the inner space
and the outer space;
a blocking piston and a first support spring which are arranged in the outer
space and slide
in an axial direction, wherein the blocking piston has a blocking position for
blocking the
communication hole and an opening position for opening the communication hole,
the first
support spring axially supports the blocking piston at the blocking position,
and the blocking
piston can be pushed by the formation fluid to move from the blocking position
to the opening
position.
As a preferred embodiment, the single flow mechanism is a uniflow ball
fracturing sliding
sleeve which is connected with a lower end of the regulating flow and
controlling water sieve
pipe.
The uniflow ball fracturing sliding sleeve includes: an outer sleeve, and an
inner sliding
sleeve slidably sleeved inside the outer sleeve, wherein the interior of the
inner sliding sleeve
constitutes a central passage and is fixed with a ball seat, a sliding block
fixedly connected
outside the inner sliding sleeve and a second support spring axially
supporting the sliding block
are arranged between the inner sliding sleeve and the outer sleeve, the
sliding block is fixedly
connected with the outer sleeve through a shearing pin, the outer sleeve is
provided with the
acidifying hole, and the inner sliding sleeve is fixed by the shearing pin at
a position where the
acidifying hole is blocked.
When the ball seat is blocked by a throw ball, which is impacted to cause the
pressure in
the central passage to exceed a certain pressure, the ball seat drives the
inner sliding sleeve and
Date Recue/Date Received 2022-05-09
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the sliding block to cut the shearing pin and move axially to open the
acidifying hole, and the
second support spring pushes the inner sliding sleeve to block the acidifying
hole again when
the impaction is stopped.
As a preferred embodiment, the upper end of the sheath is connected to an
upper joint, and
the lower end thereof is connected to a lower joint. The inner sliding sleeve
blocks the acidifying
hole at such a position that the upper end of the inner sliding sleeve is
sealed and sleeved in the
upper joint, and the lower end of the inner sliding sleeve is sealed and
sleeved in the lower joint.
As a preferred embodiment, the regulating flow and controlling water
acidification device
is a channel conversion type regulating flow and controlling water segmented
acidifying pipe
string, and the single flow controlling water sieve pipe and the uniflow ball
fracturing sliding
sleeve constitute a regulating flow and controlling water acidification
assembly.
The channel conversion type regulating flow and controlling water segmented
acidifying
pipe string includes a top packer, a plurality of the regulating flow and
controlling water
acidification assemblies, an isolation packer connected between two adjacent
regulating flow
and controlling water acidification assemblies, a wellbore isolation valve,
and a two-stage
floating shoe.
As a preferred embodiment, the regulating flow and controlling water sieve
pipe is a one-
way valve type controlling water sieve pipe, wherein the unidirectional
component is looped
between the outer pipe and the base pipe to cause the regulating flow and
controlling water space
to be formed axially into a first axial space communicating with the sieve
mesh portion and a
second axial space communicating with the regulating flow and controlling
water member that
are spaced from each other.
The unidirectional component includes a first unidirectional ball seat and a
second
unidirectional ball seat which are connected oppositely in an axial direction,
wherein in the
flowing direction of the formation fluid, the first unidirectional ball seat
is disposed upstream of
the second unidirectional ball seat, the first unidirectional ball seat has a
first number of first
channels distributed in a circumferential direction, the second unidirectional
ball seat has more
than a first number of second channels distributed in the circumferential
direction; wherein the
first number of second channels are disposed in one-to-one alignment with the
first plurality of
first channels in the axial direction, and the remaining number of second
channels are staggered
from the first channels; in the first channels and the second channels which
are aligned in the
axial direction, the end portions of the first and second channels that are
relatively buckled are
provided with ball seats respectively, and a blocking valve ball is arranged
in the ball seats which
are relatively buckled.
Date Recue/Date Received 2022-05-09
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As a preferred embodiment, the single flow mechanism is a two-stage fracturing
sliding
sleeve connected to the lower end of the one-way valve type controlling water
sieve pipe; the
two-stage fracturing sliding sleeve includes:
a sliding sleeve body which is provided with the acidifying hole;
an upper valve seat sliding sleeve slidably sleeved in the sliding sleeve
body, and a lower
valve seat sliding sleeve located below the upper valve seat sliding sleeve;
wherein the inner
diameter of the lower valve seat sliding sleeve is smaller than the inner
diameter of the upper
valve seat sliding sleeve; the lower valve seat sliding sleeve is positioned
by the shearing pin at
a position where the acidifying hole is blocked; the upper valve seat sliding
sleeve is positioned
above the lower valve seat sliding sleeve by the shearing pin; after being
blocked by a throw
ball, the lower valve seat sliding sleeve can be pushed by pressure to a
position where the
acidifying hole is opened; after being blocked by a throw ball, the upper
valve seat sliding sleeve
can be pushed by pressure to a position where the acidifying hole is re-
blocked.
As a preferred embodiment, the lower end of the sliding sleeve body is
connected with a
lower joint; a part of the lower joint that extends into the lower end of the
sliding sleeve body
has a limiting end; the lower valve seat sliding sleeve is axially limited by
the lower joint when
being pushed by the throw ball into contact with the limiting end; the upper
valve seat sliding
sleeve is axially limited by the lower valve seat sliding sleeve when being
pushed by the throw
ball into contact with the lower valve seat sliding sleeve, and the acidifying
hole is re-blocked.
As a preferred embodiment, the regulating flow and controlling water
acidification device
is a unidirectional valve type regulating flow and controlling water
acidifying pipe string; and
the one-way valve type controlling water sieve pipe and the two-stage
fracturing sliding sleeve
constitute a regulating flow and controlling water acidification assembly.
The channel conversion type regulating flow and controlling water segmented
acidifying
pipe string includes a top packer, a plurality of the regulating flow and
controlling water
acidification assemblies, an isolation packer connected between two adjacent
regulating flow
and controlling water acidification assemblies, a wellbore isolation valve,
and a two-stage
floating shoe.
As a preferred embodiment, the regulating flow and controlling water sieve
pipe is an
adaptive regulating flow and controlling water sieve pipe which includes a
sieve mesh base pipe
and a water controlling base pipe; the sieve mesh base pipe and the water
controlling base pipe
are connected to form a base pipe.
A flow guide channel is formed between the sieve mesh portion and the base
pipe. A
connecting component is fixedly connected outside the base pipe. The
connecting component is
Date Recue/Date Received 2022-05-09
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fixedly connected with the lower end of the outer protection sheath and the
upper end of the
outer pipe. The connecting component is provided with a communication channel
which
communicates the flow guide channel with the regulating flow and controlling
water space.
The water controlling base pipe is connected to the inner wall of the outer
pipe respectively
at both axial ends of the regulating flow and controlling water space. The
water controlling base
pipe is further provided with a wall clamping channel upstream of the
regulating flow and
controlling water space. A communication annulus is further arranged between
the upper end of
the water controlling base pipe and the connecting component. The
communication annulus is
communicated between the communication channel and the wall clamping channel.
As a preferred embodiment, the single flow mechanism is a single flow
fracturing pass
assembly connected to the upper end of the regulating flow and controlling
water sieve pipe; the
single flow fracturing pass assembly includes:
an outer cylinder which is provided with the acidifying hole and a micro check
valve
disposed in the acidifying hole;
an inner pipe body fixedly sleeved in the outer cylinder; wherein the interior
of the inner
pipe body is formed as a central passage; the central passage has an outflow
hole; the outflow
hole is in communication with an intermediate annulus between the inner pipe
body and the
outer pipe body; in the intermediate annulus, a rubber sealing sleeve is
further arranged for
covering the outflow hole that is fitted and sleeved outside the inner pipe
body; the rubber sealing
sleeve is capable of opening the outflow hole when the pressure within the
central passage
exceeds a first predetermined pressure.
As a preferred embodiment, the micro check valve includes: a valve body fixed
in the
acidifying hole, a baffle plate fixed to an outer end of the valve body in a
radial direction, a valve
ball located in the valve body, and a spring located between the valve ball
and the baffle plate;
the valve body has a valve body seat blocked by the valve ball at a radially
inner end.
As a preferred embodiment, the wall thickness of the rubber sealing sleeve is
in a stepped
manner in the axial direction from the upper end to the lower end; wherein the
stepped wall
thickness at the upper side is greater than that at the lower side.
As a preferred embodiment, the regulating flow and controlling water
acidification device
is an adaptive regulating flow and controlling water acidifying pipe string;
and the single flow
fracturing pass assembly and the adaptive regulating flow and controlling
water sieve pipe
constitute a regulating flow and controlling water acidification assembly.
The adaptive regulating flow and controlling water acidifying pipe string
includes a top
packer and a plurality of the regulating flow and controlling water
acidification assemblies;
Date Recue/Date Received 2022-05-09
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wherein an expansion packer is arranged above and below each of the regulating
flow and
controlling water acidification assemblies; and the adaptive regulating flow
and controlling
water sieve pipe is further provided with a centralizer.
A regulating flow and controlling water acidification well completion device
for an oil and
gas well, comprising: a top packer, a plurality of regulating flow and
controlling water
acidification assemblies, a wellbore isolation valve and a floating shoe which
are connected in
turn from top to bottom; wherein an isolation packer is arranged between each
two adjacent
regulating flow and controlling water acidification assemblies; the regulating
flow and
controlling water acidification assembly includes a regulating flow and
controlling water sieve
pipe and a single flow mechanism connected with the regulating flow and
controlling water sieve
pipe.
The regulating flow and controlling water sieve pipe has a base pipe, a sieve
mesh portion
disposed on the base pipe and a regulating flow and controlling water portion
communicating
with the sieve mesh portion; the sieve mesh portion is used for filtering the
formation fluid; the
regulating flow and controlling water portion is connected downstream of the
sieve mesh
portion, for increasing the flow resistance of water in the formation fluid;
the base pipe is further
provided with a unidirectional component which is configured to allow fluid to
flow from the
sieve mesh portion to the regulating flow and controlling water portion, while
preventing the
fluid from flowing from the regulating flow and controlling water portion to
the sieve mesh
portion.
A central passage communicating with the base pipe and an acidifying hole
communicating
the central passage with the outside of the single flow mechanism are provided
in the single flow
mechanism, wherein the single flow mechanism is configured to operatively open
and close the
acidifying hole by off-well impaction.
A use method of a regulating flow and controlling water acidification well
completion
device for an oil and gas well as described above, comprising:
running the regulating flow and controlling water acidification well
completion device into
the well, and performing automatic grouting by the wellbore isolation valve
during the run-in
process, wherein the fluid enters the inside of the regulating flow and
controlling water
acidification well completion device through the hole of the wellbore
isolation valve, to maintain
the pressure balance inside and outside the regulating flow and controlling
water acidification
well completion device;
throwing the ball to close the wellbore isolation valve after running the
regulating flow and
controlling water acidification well completion device in place;
Date Recue/Date Received 2022-05-09
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after the wellbore isolation valve is closed, setting the isolation packer
step by step to isolate
the upper and lower different formations through the isolation packer;
when acidifying the formation, opening the acidifying hole of the single flow
mechanism,
and starting acidification of the formation through oil pipe impaction; at
this time, the regulating
flow and controlling water sieve pipe cannot communicate with the outside
through the
unidirectional component, and the acidifying fluid enters the formation only
through the
acidifying hole of the single flow mechanism to complete acidifying the
formation; after
completion of acidification, stopping impaction, and closing the acidifying
hole of the single
flow mechanism;
acidifying the formations one by one from bottom to top;
during production, closing the acidifying hole of the single flow mechanism,
wherein the
oil and gas pass through filtering by the sieve mesh portion of the regulating
flow and controlling
water sieve pipe, and water controlling and throttling by the regulating flow
and controlling
water portion, in sequence in the forward direction, enter the oil pipe and
finally reach the ground
surface to complete the production.
The invention has the following beneficial effects:
With the regulating flow and controlling water acidification well completion
device
provided by the invention, the regulating flow and controlling water sieve
pipe is matched with
the single flow mechanism, which realizes the function of performing
production by the original
pipe string after acid fracturing by running the pipe string in one trip, and
has the effect of
controlling water and inhibiting edge and bottom water coning of the oil and
gas wells, in this
way, the low-water-content production period of the oil and gas well is
prolonged, the recovery
efficiency of the oil and gas well is improved, and the purposes of reducing
the operation
procedure and saving the process cost are achieved.
Multiple sets of regulating flow and controlling water sieve pipes and single
flow
mechanisms are arranged in the pipe string, which can overcome the problem
that one trip of
pipe string can not realize the integration of segmented acid fracturing and
regulating flow and
controlling water, by running a tool device and a pipe string system that
integrate the segmented
acid fracturing completion and the production and water control functions in
one-pass operation.
Specific embodiment of the invention is disclosed in detail with reference to
the following
description and the accompanying drawings, indicating the manner in which the
principles of
the invention may be employed. It should be understood that the embodiment of
the present
invention is not thus limited in scope.
The features described and/or shown for one embodiment can be used in one or
more other
Date Recue/Date Received 2022-05-09
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embodiments in the same or similar manner, can be combined with the features
in other
embodiments or replace the features in other embodiments.
It should be emphasized that, the term "include/contain" refers to, when being
used in the
text, existence of features, parts, steps or assemblies, without exclusion of
existence or
attachment of one or more other features, parts, steps or assemblies.
Brief Description of the Drawings
In order to more clearly explain the embodiments of the invention or the
technical solution
in the prior art, drawings that need to be used in the description in
embodiments or the prior art
will be simply introduced below, obviously the drawings in the following
description are merely
some examples of the invention, for persons ordinarily skilled in the art, it
is also possible to
obtain other drawings according to these drawings without making creative
efforts.
FIG. 1 is a structural schematic of a regulating flow and controlling water
member provided
by an embodiment of the present invention;
FIG. 2 is a stereoscopic view of FIG. 1;
FIG. 3 is a structural schematic of a regulating flow and controlling water
member provided
by another embodiment of the present invention;
FIG. 4 is a sectional view of FIG. 3;
FIG. 5 is a stereoscopic view of FIG. 3;
FIG. 6 is a structural schematic of a regulating flow and controlling water
member provided
by another embodiment of the present invention;
FIG. 7 is a stereoscopic view of FIG. 6;
FIG. 8 is a structural schematic of a regulating flow and controlling water
member provided
by another embodiment of the present invention;
FIG. 9 is a stereoscopic view of FIG. 8;
FIG. 10 is a structural schematic of a regulating flow and controlling water
member
provided by another embodiment of the present invention;
FIG. 11 is a stereoscopic view of FIG. 10;
FIG. 12 is a structural schematic of a channel conversion type regulating flow
and
controlling water segmented acidifying pipe string provided by an embodiment
of the present
invention;
FIG. 13 is a half sectional structural schematic of a one-way valve type
controlling water
sieve pipe of FIG. 12;
FIG. 14 is a sectional structural schematic of FIG. 13;
FIG. 15 is a structural schematic of a sieve mesh portion of FIG. 13;
Date Recue/Date Received 2022-05-09
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FIG. 16 is a half sectional structural schematic of a uniflow ball fracturing
sliding sleeve of
FIG. 12;
FIG. 17 is a sectional structural schematic of FIG. 16;
FIG. 18 is a schematic shows state of a regulating flow and controlling water
portion of
FIG. 13 in the acid fracturing process;
FIG. 19 is a schematic shows state of a regulating flow and controlling water
portion of
FIG. 13 in the production process;
FIG. 20 is a structural schematic of a unidirectional valve type regulating
flow and
controlling water acidifying pipe string provided by another embodiment of the
present
invention;
FIG. 21 is a half sectional structural schematic of a one-way valve type
controlling water
sieve pipe of FIG. 20;
FIG. 22 is a sectional structural schematic of FIG. 21;
FIG. 23 is a half sectional structural schematic of a two-stage fracturing
sliding sleeve of
FIG. 20;
FIG. 24 is a sectional structural schematic of FIG. 23;
FIG. 25 is a structural schematic of a check valve of FIG. 21;
FIG. 26 is a schematic shows state of FIG. 25 in the acid fracturing process;
FIG. 27 is a schematic shows state of FIG. 25 in the production process;
FIG. 28 is a structural schematic of an adaptive regulating flow and
controlling water
acidifying pipe string provided by another embodiment of the present
invention;
FIG. 29 is a half sectional structural schematic of a single flow fracturing
pass assembly of
FIG. 28;
FIG. 30 is a sectional structural schematic of FIG. 29;
FIG. 31 is a sectional structural schematic of a micro check valve of FIG. 29;
FIG. 32 is a sectional structural schematic of a rubber sealing sleeve of FIG.
29;
FIG. 33 is a sectional structural schematic of an adaptive regulating flow and
controlling
water sieve pipe of FIG. 28.
Detailed Description of the Preferred Embodiments
In order to make those skilled in the art better understand the technical
solutions in the
present invention, the technical solutions in the embodiments of the present
invention will be
clearly and completely described in the following with reference to the
accompanying drawings
in the embodiments of the present application. Obviously, the described
embodiments are only
a part of the embodiments of the present invention, but not all of them. Based
on the
Date Recue/Date Received 2022-05-09
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embodiments of the present invention, all other embodiments that are obtained
by persons skilled
in the art without making creative efforts shall fall within the protection
scope of the present
invention.
It should be noted that when an element is referred to as being "disposed" on
another
element, it may be directly on another element or there may be another element
in the middle.
When one element is considered to be "connected" to another element, it may be
connected
directly to another element or there may be another element in the middle. The
terms "vertical,"
"horizontal," "left," "right" and other similar expressions used herein are
used for illustrative
purposes only and are not meant to be the only embodiment.
Unless otherwise defined, all technical and scientific terms used herein have
the same
meanings as that are generally understood by those skilled in the art
belonging to the technical
field of the present invention. The terms used herein in the description of
the invention are for
purposes of describing specific embodiments only and are not intended to limit
the invention.
The terms "and/or" as used herein include any and all combinations of one or
more related listed
items.
It should also be noted that "upper" and "lower" in the present disclosure may
be understood
to define a far and near relationship to the wellhead, two adjacent
components, in undefined
location terms, unless explicitly defined. Among two adjacent members, the
member close to
the wellhead is located above the member far from the wellhead, and different
portions of the
same member are also defined in accordance with distance from the wellhead.
Referring to FIGs. 1 and 2, an embodiment of the present disclosure provides a
regulating
flow and controlling water member as an oil-gas-water three-phase inflow
adaptive regulating
flow and controlling water core control mechanism (AICD). The embodiment
provides a
regulating flow and controlling water member disposed in the well and adapted
to receive
incoming fluid.
As a fluid inflow control mechanism, the regulating flow and controlling water
member
introduces relatively small flow resistance and relatively small pressure drop
to a desired fluid
(e.g., oil and gas in an oil and gas well) by introducing relatively large
flow resistance and
relatively large pressure drop to unwanted fluid (e.g., water in oil and gas
well), in this way, the
desired fluid flows into the control mechanism, which may reduce the
proportion of the
unwanted fluid in the produced fluid, allowing the oil and gas wells to
maintain efficient
production.
The regulating flow and controlling water member includes a chamber 2, an
outlet 3 and at
least one inlet 1. The chamber 2 has a first end (which is an upper end in
FIG. 2, and the first
Date Recue/Date Received 2022-05-09
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end is a radially outer end in the radial direction of the base pipe when it
is installed on the
regulating flow and controlling water sieve pipe) and a second end (which is a
lower end in FIG.
2, and the first end is a radially inner end in the radial direction of the
base pipe when it is
installed on the regulating flow and controlling water sieve pipe), and the
cross section of the
chamber is reduced along the extension thereof. The first end of the chamber 2
is a cylindrical
chamber, and the second end thereof is a cylindrical chamber having an inner
diameter smaller
than that of the first end. In the regulating flow and controlling water
member, the ratio between
the diameter of the inlet 1 and the diameter of the outlet 3 and the flow
channel height is 1: 1.8
¨ 2.8: 4.5 ¨ 6.5. The flow channel height is a vertical height from the top of
the chamber 2 to the
outlet 3 when facing FIG. 2, and may also be the distance between the inlet 1
and the outlet 3 in
the vertical direction when facing FIG. 2. The ratio of the inner diameter of
the inlet 1 or the
flow channel of the inlet 1 to maximum inner diameter of the swirl chamber 2
is 1: 4.5 ¨ 7.5.
The regulating flow and controlling water member is of a stepped shape, of
which the outer
diameter of a portion corresponding to the first end of the chamber is larger
than that of a portion
corresponding to the second end of the chamber, so as to be conveniently
positioned and installed
in the communication hole of the base pipe.
The chamber outlet 3 is the second end of the chamber. The inlet 1 has a
transverse
dimension for receiving fluid and delivering the fluid to the first end of the
chamber 2. The inlet
1 is a linear type flow channel and goes into (the first end of) the chamber 2
in a substantially
tangential direction, so that a fluid rotating in the direction of the section
of the chamber 2
towards the outlet is generated inside the chamber 2. Meanwhile, an oil-water
variable friction
structure (damping structure) may be added between the inlet 1 and the first
end of the chamber
2, so as to further achieve the purpose of oil-gas-water separation.
The regulating flow and controlling water member has more favorable pressure
and flow
rate characteristics for the desired fluid (oil and gas) to be produced. When
the formation fluid
flows into the device and is throttled by the flow channel of the inlet 1, the
fluid forms a jet flow.
When the incoming fluid is oil, the velocity of the formed jet flow is
relatively small due to the
relatively small density and relatively large viscosity of the oil, thus the
rotation increasing effect
in the vortex chamber is limited, and the jet flow quickly flows out from the
central outlet 3, and
the throttling resistance generated within the entire device is relatively
small. When water enters
the water controlling device, since the density of water is relatively large,
the viscosity is small
and the inertia force is large, the velocity of the formed jet flow is
relatively large, then the effect
of increasing the rotation in the vortex cavity is obvious, a high-speed
swirling flow is formed
in the swirl chamber 2, thereby generating a large throttling resistance.
Date Recue/Date Received 2022-05-09
14
The regulating flow and controlling water member includes a vortex inducer of
the inlet 1,
which generates a jet flow of the incoming fluid and directs the jet flow into
the chamber 2 of
the regulating flow and controlling water member. In the chamber 2, the jet
flow generates a
rotating flow as well as an axial flow which is diverted towards the outlet 3
of the chamber 2. In
the rotation chamber 2, the gravitational potential energy of the fluid is
converted into the kinetic
potential energy rotating to the center, and the kinetic potential energy of
the tangential motion
is converted at the central outlet 3 into a throttling resistance generated by
the entire regulating
flow and controlling water member. Therefore, the resistance of the entire
water controlling
device to water is large, and due to the high viscosity of the oil, the
throttling resistance formed
in the throttling member is relatively small, and the viscous force and
inertial force of gas are
very small, thus the throttling resistance formed in the water controlling
device is also very small.
The regulating flow and controlling water member is an integrated structure,
and is formed
of a material suitable for use in a downhole environment and having strong
structural integrity,
such as steel or tungsten carbide, which may be formed by machining, injection
molding,
casting, or the like. The overall size of the device is small, the height is
about 14 to 18 mm, the
diameter of the upper section is 18 to 20 mm, the diameter of the lower
section is 4 to 6 mm,
and the diameter of outlet is 1.6 to 4.5 mm. The exterior of the lower end of
the device is designed
with thread, which is convenient to install on the pipe string of oil and gas
well.
FIGs. 1 and 2 show a transverse section and a 3-dimensional view of a swirl
structure of
dual inlets 1, respectively. It can be seen from the figure that the structure
includes two fluid
inlets 1 which feed the tangential jet flow into the swirl chamber 2
respectively. Referring to
FIG. 2, it can be seen that the swirl chamber 2 is an inverted conical inner
chamber 2. The inlet
1 passes through the wall of the chamber 2, and the second end of the chamber
2 is a fluid outlet
33.
The vortex flow in the regulating flow and controlling water member forms a
low pressure
region in an eye region closest to the axis. The oil having higher viscosity
rotates at a lower
speed, and the fluid having lower viscosity, such as gas or water, has a much
higher rotational
speed, and the lower pressure at the eye effectively chokes the fluid flow.
Thus, the regulating
flow and controlling water member is responsive mainly to fluid viscosity. The
induced
rotational flow results in a pressure drop, and the degree of the pressure
drop is a function of the
characteristics of the flowing fluid. The strength of the flow reduction
increases as the viscosity
of the fluid decreases, reaching a maximum in the pure gas flow.
As shown in FIGs. 3 and 4, another embodiment of the present disclosure also
provides a
regulating flow and controlling water member, in which long and short flow
channel design is
Date Recue/Date Received 2022-05-09
15
added as compared with the regulating flow and controlling water member in
FIGs. 1 and 2.
FIGs. 3 and 4 are a front view and a transverse sectional view of the long and
short flow channel
structure, respectively. The regulating flow and controlling water member
includes four
cylindrical inlet flow passages, and the flow channel lengths are different
(the inlet flow channel
includes a short flow channel 4 and a long flow channel 5). The short flow
channel 4 and the
long flow channel 5 are merged, and then reach the inlet end 6 of the swirl
chamber through one-
time diameter reduction. The inlet end 6 communicates between the short flow
channel 4, the
long flow channel 5 and the chamber 7. The overflow area of the inlet end 6 is
smaller than the
sum of the overflow areas of the short flow channel 4 and the long flow
channel 5. The ratio of
the diameter of the long flow channel 5 to the diameter of the short flow
channel 4 is 1: 1 ¨ 1.4.
The ratio of the long flow channel 5 to the length of the short flow channel
is 3 ¨ 5.5: 1.
The second end of the swirl chamber 7 (the second end is a radial inner end
when installed
on the regulating flow and controlling water sieve pipe, and the end can be
used as a stepped
through hole inserted into the base pipe wall for positioning and
installation) is a fluid outlet 8,
in which the swirl chamber 7 is an internal chamber of an inverted conical
type, which is
consistent with the internal chamber structure of the dual-inlet swirl
structure in FIGs. 1 and 2.
FIG. 5 is a three-dimensional view of the long and short flow channel
structure.
On the basis of regulating flow and controlling water with the dual-inlet
swirl structure of
the long and short flow channels 4 and 5, two new inlet flow channels have
been added, which
can effectively increase the oil passing area and reduce the resistance of the
device to oil, and
reduce the formation of a turbulent flow region through the design of the long
and short flow
channels. In addition, a plurality of local throttle mechanisms are added to
the whole structure,
so that the resistance to water is greatly increased, and the control function
to the water is further
strengthened. The reduction in the diameter of the inlet end 6 is effective to
increase the flow
rate and make it easier for the fluid to form a jet flow flowing along the
section of the swirl
chamber. The control resistance of the structure to water is further enhanced,
and the pressure
ratio of the water-oil overflow is further amplified.
In order to further increase the pertinence of oil, gas and water control, an
oil-gas-water
adaptive regulating flow and controlling water member with a multi-branch flow
channel
structure is established by adding branch flow channels. As shown in FIGs. 6
and 7, an
embodiment of the present disclosure further provides an oil-gas-water
adaptive regulating flow
and controlling water member with a multi-branch flow channel structure. FIGs.
6 and 7 are a
top perspective view and a longitudinal perspective view of a multi-branch
flow channel
structure, respectively. FIG. 7 is a three-dimensional view of the multi-
branch flow channel
Date Recue/Date Received 2022-05-09
16
structure.
The regulating flow and controlling water member includes two rectangular
inlet flow
channels 9. The cross-sectional area of the rectangular inlet flow channel 9
is a rectangular
structure. A plurality of branch flow channels 10 and two flow guide channels
11 for guiding
the swirling motion of the fluid in the swirl chamber 12 extend along the
interior of the flow
channel 9, wherein as shown in FIG. 7, the flow channel height gradually
decreases from the
inlet flow channel 9 to the flow guide channel 11 with a descending grade. The
bottom end of
the regulating flow and controlling water member is a fluid outlet 13.
Specifically, the ratio of the diameter of the inlet flow channel 9 (flow
channel width in the
state shown in FIG. 6) to the diameter of the outlet 13 is 1: 1.8 ¨ 2.5. The
ratio of the diameter
of the inlet flow channel 9 (flow channel width in the state shown in FIG. 6)
to the diameter of
the branch flow channel 10 (flow channel width in the state shown in FIG. 6)
is 1¨ 1.2: 1. The
ratio of the inlet height of the inlet flow channel 9 to the outlet height of
the inlet flow channel
9 is 3: 2. The outlet of the inlet flow channel 9 is the inlet of the flow
guide channel 11. The flow
channel width of the inlet flow channel 9 remains unchanged in the state shown
in FIG. 6, and
the flow channel width of the flow guide channel 11 in the state shown in FIG.
6 gradually
decreases in the flow direction.
On the basis of the mechanism of regulating flow and controlling water with
dual-inlet
swirl, the design of the oil-water diversion mechanism and the oil-water
variable friction
structure are added in the inlet flow channel 9 of the multi-branch flow guide
structure, so as to
achieve the purpose of water control and oil stabilization. The branch flow
channel 10 plays a
role of oil-passing and water-blocking by utilizing a local friction effect.
The flow guide channel
11 plays a role of water-passing and oil-blocking by utilizing a friction
effect along the path. At
the same time, the height difference between the flow channel inlet and outlet
makes it easier
for water to form a jet flow flowing along the section of the swirl chamber.
This structure causes
the fluid to be relatively less dense during the swirling process and to first
flow rapidly towards
the fluid outlet 13 for a relatively large amount of oil, and the denser water
rotates along the
swirl chamber, so as to play the role of water control and oil stabilization.
In addition, the
presence of the branch flow channel 10 further causes the oil flowing out of
the branch flow
channel 10 to flow in a straight line to the center outlet, and the water
flowing out of the flow
guide channel is more likely to rotate into the swirl chamber, thereby forming
a high throttling
resistance in the center of the swirl chamber.
In order to further increase the comprehensive control ability of water
control, oil
stabilization and gas production of the adaptive regulating flow and
controlling water member,
Date Recue/Date Received 2022-05-09
17
movable small balls can be arranged in the swirl chamber of three kinds of
conical structures
(the chamber of the adaptive regulating flow and controlling water member of
FIGs. 1 to 7 may
be referred to as a swirl chamber), and the movable small balls in the swirl
chamber are made of
different materials according to the specific density requirements. When the
density of the
incoming fluid is smaller than the density of the small balls, the centrifugal
force acting on the
fluid is smaller than that acting on small balls, and the small balls will
have a greater buoyancy,
so that the small balls will rotate upward around the swirl chamber (i.e., the
farther end from the
fluid outlet); conversely, when the density of the incoming fluid is greater
than that of the small
balls, the small balls will move toward the fluid outlet. The mechanism can
utilize this effect to
selectively produce or restrict fluid flow of different densities, such as gas-
production and water
control, and oil-production and water control.
Three kinds of oil, gas and water three-phase adaptive regulating flow and
controlling water
mechanisms with roughly conical shape are given above. The conical regulating
flow and
controlling water member has the advantages of convenient installation, a
large relative overflow
area of the swirl chamber, and increase of the oil-water resistance variation
through conical
vortex flow.
Considering the limitation of its own volume, the passing area and rotating
vortex of a
single conical throttle member are relatively small, for the convenience of
field application, on
the basis of the conical regulating flow and controlling water member, the
present disclosure
also proposes two embodiments of a planar-shaped adaptive regulating flow and
controlling
water member. The regulating flow and controlling water member acts as a water
control
throttling member to regulate and control the formation fluid.
FIGs. 8 and 9 show a structural schematic of a planar-shaped regulating flow
and
controlling water member. FIGs. 8 and 9 are a top perspective view and a three-
dimensional
perspective view of a planar-shaped dual-inlet regulating flow and controlling
water member,
respectively. The regulating flow and controlling water member includes two
funnel-shaped
inlet flow channels 14, two narrow fluid acceleration channels 15, a fluid
swirl disk 16 and a
central outlet 11. As shown in FIG. 9, the fluid acceleration channel 15 is
tangent to the swirl
disk 16. The formation fluid flows into the regulating flow and controlling
water member, then
enters the regulating flow and controlling water member from the inlet flow
channel 14, is shut
off and accelerated through the fluid acceleration channel 15 and then enters
the central swirl
disk 16. The ratio of the diameter of the central swirl disk 16 to the
diameter of the central outlet
is (8.5 ¨ 12): 1. Due to low viscosity and high density of the water, the
water enters the swirl
disk 16 in a tangential direction to form a high-speed swirl in the swirl disk
16. According to the
Date Recue/Date Received 2022-05-09
18
law of conservation of rotational momentum, the water forms a high additional
resistance in the
swirl disk 16 by rotating at a high speed, which in turn increases the
additional pressure
generated by the entire throttle member. Due to high viscosity and relatively
low density of oil,
it is difficult for the oil to form a high-speed rotational flow in the swirl
disk 16 like water, so
that the oil flows out to the central outlet more quickly. The rotation
control of the central swirl
disk 21 of the entire throttle mechanism is crucial. The ratio of the diameter
of the swirl disk 16
to the height of the entire regulating flow and controlling water member is 10
¨ 12: 1. The ratio
between the length, width, and height of the flow channel acceleration channel
15 is 9 ¨ 11: 1 ¨
1.5: 1.2 ¨ 1.8.
FIGs. 10 and 11 show a structural schematic of another planar-shaped
regulating flow and
controlling water member. FIGs. 10 and 11 are a top perspective view and a
three-dimensional
perspective view of a planar-shaped multi-branch regulating flow and
controlling water member
structure, respectively. The regulating flow and controlling water member
includes two funnel-
shaped inlet flow channels 18, eight branch channels 19, two gradually
narrowing flow guide
channels 20, a fluid swirl disk 21 and a central outlet 22.
Here as shown in FIG. 11, eight branch flow channels 19 are formed by
separating end face
projections. The projection structure (end surface projection) is
perpendicular to the flow guide
channel 20 at the same position. Meanwhile, the end angle of the projection
structure in the
incoming direction is a sharp angle, and in such structure, vortex will be
formed in the branch
flow channel when the incoming fluid is the water with a large inertia force,
so as to block water
from flowing into the branch flow channel, and ensure that substantially all
(at least most) of the
water flowing into the throttle member enters the flow guide channel 20, and
the flow guide
channel 20 is a channel that tapers from an inlet end to an outlet end.
Specifically, the ratio of
the inlet end width of the flow guide channel 20 to the outlet end width is 3:
2. The outlet of the
flow guide channel 20 is tangent to the swirl disk 21, so as to ensure that
the formation water
flowing into the throttle member enters the swirl disk 20 through the tangent
line. The ratio of
the diameter of the central swirl disk 21 to the diameter of the central
outlet is: (6.5 ¨ 10.5): 1.
Due to low viscosity and high density of the water, the water enters the swirl
disk 21 in a
tangential direction to form a high-speed swirl in the swirl disk 21.
According to the law of
.. conservation of rotational momentum, the water forms a high additional
resistance in the swirl
disk 21 by rotating at a high speed, which in turn increases the additional
pressure generated by
the entire throttle member. Due to high viscosity and relatively low density
of oil, the oil entering
the planar-shaped multi-branch flow guide regulating flow and controlling
water member will
directly flow to the central outlet through the branch flow channel, and the
additional resistance
Date Recue/Date Received 2022-05-09
19
generated in the throttle member is relatively small. The ratio of the
diameter of the swirl disk
21 to the height of the entire throttle mechanism (regulating flow and
controlling water member)
is 8.5 ¨ 10.5: 1. The ratio between the length, width, and height of the flow
channel acceleration
channel is 9 ¨ 11: 1 ¨ 1.5: 1.2 ¨ 1.8.
Referring to FIGs. 12 to 19, an embodiment of the present disclosure provides
a regulating
flow and controlling water acidification device, specifically, a regulating
flow and controlling
water acidification well completion device for an oil and gas well. The
regulating flow and
controlling water acidification well completion device for an oil and gas well
comprises a
regulating flow and controlling water sieve pipe 52 and a single flow
mechanism 53 connected
to the regulating flow and controlling water sieve pipe 52.
The sieve pipe has a base pipe 522, a sieve mesh portion 524 disposed on the
base pipe 522
and a regulating flow and controlling water portion 520 communicating with the
sieve mesh
portion 524. The sieve mesh portion 524 is used for filtering the formation
fluid. The regulating
flow and controlling water portion 520 is connected downstream of the sieve
mesh portion 524,
for increasing the flow resistance of water in the formation fluid. A central
passage
communicating with the base pipe 522 and an acidifying hole communicating the
central passage
with the outside of the single flow mechanism 53 are provided in the single
flow mechanism 53.
The single flow mechanism 53 is configured to operatively open and close the
acidifying hole
by off-well impaction. The single flow device only allows fluid to flow from
the central passage
through the acidifying hole to the outside of the single flow mechanism 53.
The single flow
mechanism 53 may be installed at the upper end of the regulating flow and
controlling water
sieve pipe 52 or at the lower end thereof, and the present application is not
limited thereto.
In order to cooperate with the single flow mechanism 53 so as to ensure that
acidifying
fluid enters the layer to be acidified through the acidifying hole as much as
possible, and the
base pipe 522 is further provided with a unidirectional component. The
unidirectional
component allows a flow direction to be reversed from that of the single flow
mechanism 53.
The unidirectional component is configured to allow fluid to flow from the
sieve mesh portion
524 to the regulating flow and controlling water portion 520, while preventing
the fluid from
flowing from the regulating flow and controlling water portion 520 to the
sieve mesh portion
524. In the flow direction of the formation fluid, the unidirectional
component is upstream of
the regulating flow and controlling water member 534.
In this embodiment, as shown in FIG. 15, the sieve mesh portion 524 includes
an outer
protection sheath 20, a filter screen 21, a flow guiding mesh 22, a filter
screen 23, a flow guiding
Date Recue/Date Received 2022-05-09
20
mesh 24 and a supporting layer 25 which are sleeved in order from the outside
to the inside.
Circular through holes are distributed on the outer protection sheath 20. The
filter screen 21, the
flow guiding mesh 22, the filter screen 23 and the flow guiding mesh 24
constitute a filter layer.
The flow guiding meshs 22 and 24 are used for guiding the fluid. The filter
screens 21 and 23,
the flow guiding meshs 22 and 24 and the supporting layer 25 are integrally
fixed by extrusion
forging.
The regulating flow and controlling water portion 520 includes an outer pipe
528 fixed to
the outer side of the base pipe 522, and a regulating flow and controlling
water member 534
mounted on the wall of the base pipe 522 inside the outer pipe 528. The
regulating flow and
controlling water member 534 is the plate-type regulating flow and controlling
water member
or the tapered regulating flow and controlling water member in the above-
described
embodiment. A regulating flow and controlling water space is formed between
the base pipe 522
and the outer pipe 528. The regulating flow and controlling water member 534
communicates
the interior 5220 of the base pipe 522 with the regulating flow and
controlling water space. After
the formation fluid enters the regulating flow and controlling water space, it
is throttled by the
regulating flow and controlling water member 534, and then the oil and gas is
input into the base
pipe 522.
In this embodiment, the regulating flow and controlling water acidification
well completion
device for an oil and gas well is a regulating flow and controlling water
segmented acidifying
pipe string 50, which separates the formation to form a plurality of
acidifying layers
(formations), and acid fracturing production operation can be performed
separately for each
acidifying layer (formation). The regulating flow and controlling water sieve
pipe 52 and the
single flow mechanism 53 constitute a regulating flow and controlling water
acidification
assembly. The regulating flow and controlling water segmented acidifying pipe
string 50
includes a top packer 51, a plurality of the regulating flow and controlling
water acidification
assemblies, an isolation packer 54 connected between two adjacent regulating
flow and
controlling water acidification assemblies, a wellbore isolation valve 55, and
a two-stage floating
shoe 56.
In an embodiment, the regulating flow and controlling water acidification well
completion
device for an oil and gas well is a channel conversion type regulating flow
and controlling water
segmented acidifying pipe string 50. The channel conversion type regulating
flow and
controlling water segmented acidifying pipe string 50 includes a top packer
51, a plurality of the
regulating flow and controlling water acidification assemblies, an isolation
packer 54 connected
between two adjacent regulating flow and controlling water acidification
assemblies, a wellbore
Date Recue/Date Received 2022-05-09
21
isolation valve 55, and a two-stage floating shoe 56.
Specifically, the channel conversion type regulating flow and controlling
water segmented
acidifying pipe string 50 includes a top packer 51, a single flow controlling
water sieve pipe 52,
a uniflow ball fracturing sliding sleeve 53, an isolation packer 54, a single
flow controlling water
sieve pipe 52, a ball fracturing sliding sleeve 53, a wellbore isolation valve
55 and a two-stage
floating shoe 56. The two-stage floating shoe 56 includes a forward two-stage
floating shoe 56
and a reverse two-stage floating shoe 56. The channel conversion type
regulating flow and
controlling water segmented acidifying pipe string 50 isolates upper and lower
acidifying layers,
and performs acidification and production work correspondingly.
As shown in FIGs. 13 and 14, the regulating flow and controlling water sieve
pipe 52 is a
single flow controlling water sieve pipe. The single flow mechanism 53 is a
uniflow ball
fracturing sliding sleeve. The regulating flow and controlling water
acidification device is a
channel conversion type regulating flow and controlling water segmented
acidifying pipe string
50. The single flow controlling water sieve pipe 52 and the uniflow ball
fracturing sliding sleeve
.. 53 constitute a regulating flow and controlling water acidification
assembly.
In this embodiment, the single flow controlling water sieve pipe 52 is
composed of the sieve
mesh portion 524 and the regulating flow and controlling water member 520. The
(adaptive)
regulating flow and controlling water member 534 (AICD) is installed on the
sieve mesh base
pipe 522. The upper end of the base pipe 522 is fixedly connected with a
collar 521.
A flow guide channel is formed between the sieve mesh portion 524 and the base
pipe 522.
As shown in FIG. 15, the sieve mesh portion 524 is mainly composed of a three-
layer structure,
and the outermost side is a circular hole outer protection sheath 20. The
outer protection sheath
20 protects the filter layer and ensures the strength and reliability of the
sieve mesh. The second
through fifth layers in the middle are filter layers. In the filter layers,
the second and fourth layers
are precise filter screens 21 and 23 (sand prevention and filtering function).
The third and fifth
layers are precision flow guiding meshes 22 and 24 (to guide the flow of
incoming fluid). The
sixth layer in the inner side is a supporting layer 25, which ensures a
sufficient circulation area
between the filter layer and the base pipe 522. The supporting layer 25, the
filter layer and the
base pipe 522 are extrusion forged by extrusion forging process, which
increases the strength by
74% while reducing the cost compared with the conventional sieve pipe.
The upper end of the outer protection sheath 20 is fixedly connected with an
upper end ring
523 that fixedly sleeves outside the base pipe 522. The lower end of the outer
protection sheath
20 is connected to the upper end of an outer pipe 528 by a mating plug 525.
The mating plug
525 is fixedly sleeved outside the base pipe 522, and a channel communicating
the regulating
Date Recue/Date Received 2022-05-09
22
flow and controlling water space with the sieve mesh portion 524 (flow guide
channel) is formed
between the mating plug 525 and the base pipe 522. The lower end of the outer
pipe 528 is
fixedly sleeved outside the lower joint 530, and is fixedly connected by a set
screw 531 to prevent
rotation.
As shown in FIGs. 18 and 19, the unidirectional component of the single flow
controlling
water sieve pipe 52 includes an overflowing sleeve 527 fixedly arranged inside
the outer pipe
528, and a blocking piston 526 and a first support spring 538. A retaining
ring 529 is fixedly
connected between the outer pipe 528 and the upper end of the lower joint 530.
The retaining
ring 529 fixedly sleeves at a rear end of an outer space 5272. The rear end of
the first support
spring 538 abuts the retaining ring, and the front end thereof abuts the
blocking piston 526. The
first support spring 538 is a cylindrical spring 538, and sleeves outside the
overflowing sleeve
527. The overflowing sleeve 527 divides the regulating flow and controlling
water space radially
to form an inner space 5271 and an outer space 5272 that is in communication
with the sieve
mesh portion 524. The regulating flow and controlling water member 534
communicates the
inner space 5271 with the interior of the base pipe 522. The overflowing
sleeve 527 is provided
with a communication hole 5270 to communicate the inner space 5271 with the
outer space
5272.
The outer wall of the lower joint 530 is provided with a sealing ring which is
fitted and
sealed between the lower end of the outer pipe 528 and the lower joint 530, to
seal the lower end
of the outer space 5272. The upper end and the lower end of the overflowing
sleeve 527 are
sealingly connected outside the upper fixing ring 530 (the upper fixing ring
fixedly sleeves
outside the base pipe 522) and the upper end of the lower joint 530,
respectively, and a sealing
ring 533 is further disposed between the upper end of the overflowing sleeve
527 and the upper
fixing ring, and between the lower end of the overflowing sleeve 527 and the
lower joint 530.
Sealing rings 535 and 537 are arranged respectively on the inner wall and the
outer wall of the
blocking piston 526, so as to block the communication hole 5270 at the initial
position.
The outer space 5272 and the inner space 5271 form an annular space separated
by the
overflowing sleeve 527. The blocking piston 526 and the first support spring
538 are disposed
in the outer space 5272. The blocking piston 526 slides axially within the
outer space 5272. The
blocking piston 526 has a blocking position for blocking the communication
hole 5270 and an
opening position for opening the communication hole 5270. The first support
spring 538 axially
supports the blocking piston 526 at the blocking position. The blocking piston
526 can be pushed
by the formation fluid to move from the blocking position (FIG. 18) to the
opening position
(FIG. 19).
Date Recue/Date Received 2022-05-09
23
The unidirectional component of the single flow controlling water sieve pipe
52 includes a
piston 526, a first support spring 538, and an overflowing sleeve 527. When
acid fracturing is
performed, as shown in FIG. 18, in a normal state, the piston 526 blocks the
overflow hole 5270
of the overflowing sleeve 527, and the acidifying fluid cannot enter the
formation through the
sieve pipe 52. As production proceeds, as shown in FIG. 19, the oil and gas
push the piston 526
to compress the spring 538, the communication hole 5270 of the overflowing
sleeve 527 is
opened, and the formation oil and gas finally enter the oil pipe through a
water control and gas
stabilization device to reach the ground surface.
It can be seen that when the single flow controlling water sieve pipe in this
embodiment
performs acidification, the piston 526 blocks the communication hole of the
overflowing sleeve
527, and the acidifying fluid cannot enter the formation through the single
flow controlling water
sieve pipe. During production, the fluid pushes the piston 526 to compress the
spring 538, to
open the channel and the fluid eventually enters the oil pipe through the
controlling water device
and reaches the ground surface.
In this embodiment, as shown in FIGs. 16 and 17, the single flow mechanism 53
is a uniflow
ball fracturing sliding sleeve. The uniflow ball fracturing sliding sleeve 53
is connected at the
lower end of the regulating flow and controlling water sieve pipe 52. The
uniflow ball fracturing
sliding sleeve 53 includes an outer sleeve 542, and an inner sliding sleeve
545 slidably sleeved
inside the outer sleeve 542. The interior of the inner sliding sleeve 545
constitutes a central
passage and is fixed with a ball seat 546. A sliding block 543 fixedly
connected outside the inner
sliding sleeve 545 and a second support spring 544 axially supporting the
sliding block 543 are
arranged between the inner sliding sleeve 545 and the outer sleeve 542. The
sliding block 543 is
fixedly connected with the outer sleeve 542 through a shearing pin 554. The
outer sleeve 542 is
provided with the acidifying hole 540, and the inner sliding sleeve 545 is
fixed by the shearing
pin 554 at a position where the acidifying hole 540 is blocked.
The upper end of the outer sleeve 542 is connected to an upper joint 541, and
the lower end
thereof is connected to a lower joint 547, which are fitted and sealed through
the sealing ring
548. The inner sliding sleeve 545 blocks the acidifying hole 540 at such a
position (position
shown in FIGs. 16 and 17) that the upper end of the inner sliding sleeve 545
is sealed and sleeved
in the upper joint 541, and the lower end of the inner sliding sleeve 545 is
sealed and sleeved in
the lower joint 547.
The lower end of the upper joint 541 is fixedly connected within an upper end
of an outer
sleeve 542. The inner wall of the lower end of the upper joint 541 is provided
with a limiting
step, and when the inner sliding sleeve 545 is at the initial position, the
upper end of the inner
Date Recue/Date Received 2022-05-09
24
sliding sleeve 545 is limited by (the limiting step of) the upper joint 541
and seals against the
inner wall of the lower end of the upper joint 541. The outer wall of the
inner sliding sleeve 545
has a carrying step. The sliding block 543 is fixed between the inner sliding
sleeve 545 and the
outer sleeve 542. The inner and outer sides of the sliding block 543 are
provided with sealing
rings 552 and 554 for sealing against the walls of the inner sliding sleeve
545 and the outer
sleeve 542. The sliding block 543 cooperates with the carrying step and is
pushed upwards by
the second support spring 544 to be fitted with the carrying step, so that the
sliding block 543
and the inner sliding sleeve 545 constitute an axial common movement. The ball
seat 546 is
fixed to the inner wall of the inner sliding sleeve 545 by a set screw 551.
The inner wall of the
upper end of the lower joint 547 has a sliding segment in which the inner
sliding sleeve 545
sleeves, and is provided with a sealing ring 549 and a blocking step. The
inner sliding sleeve
545 is pressed down until it comes into contact with the blocking step and
cannot continue to
descend, and the acidifying hole 540 is opened. The inner wall of the upper
end of the lower
joint 547 is provided with a sealing ring 549 and maintains in sealing contact
with the inner
sliding sleeve 545. A sealing ring 550 is provided between the ball seat 546
and the inner sliding
sleeve 545 for sealing.
When the ball seat 546 is blocked by a throw ball, which is impacted to cause
the pressure
in the central passage to exceed a certain pressure, the ball seat 546 drives
the inner sliding sleeve
545 and the sliding block 543 to cut the shearing pin 554 and move axially to
open the acidifying
hole 540, and the second support spring 544 pushes the inner sliding sleeve
545 to block the
acidifying hole 540 again when the impaction is stopped.
The uniflow ball fracturing sliding sleeve 53 is steel sealed to the ball seat
546 by the ball,
and impacts and pushes (the sliding block 543 of) the inner sliding sleeve 545
to cut the shearing
pin 554, so as to achieve to open the inner slide sleeve 545 and the
acidifying hole 540. After
the impaction is stopped outside the well, the inner sliding sleeve 545 is
reset under the action
of the second support spring 544 to close the acidifying hole 540.
In the application of the channel conversion type regulating flow and
controlling water
segmented acidifying pipe string 50, the following operation mode is adopted:
first, the pipe string 50 is run to a predetermined position by using a drill
stem connection
special running tool, and automatic grouting is performed by the wellbore
isolation valve 55
during the run-in process, wherein the fluid enters the inside of the pipe
string 50 through the
hole of the wellbore isolation valve 55, to maintain the pressure balance
inside and outside the
pipe string 50. After the pipe string 50 is run in place, the bal closes the
wellbore isolation valve
55. At this time, the forward two-stage floating shoe 56 can be opened, and
the reverse two-
Date Recue/Date Received 2022-05-09
25
stage floating shoe 56 is not connected.
After the wellbore isolation valve 55 is closed, the isolation packer 54 is
set step by step.
The oil pipe impacts the setting forwards, and after the setting is completed,
the isolation packer
54 is sealed. The isolation packer 54 is sealed by annulus impaction, and if
the pressure is stable,
the sealing is qualified; then a top hanging packer is set by a special
setting tool, and is annularly
sealed and hang after the setting is completed. The sleeve is impacted to
check whether the top
packer 51 is qualified, and after the sealing of the top packer 51 is
qualified, the setting tool is
annularly impacted or forward released.
When acidifying the lower layer (acidifying layer), a suitably sized acid
resistant soluble
ball is thrown onto the ball seat 546 of the uniflow ball fracturing sliding
sleeve 53 of the lower
layer. The oil pipe is impacted, and the ball seat 546 is cut from the inner
sliding sleeve 545 and
the sliding block 543 by the shearing pin 554. The inner slide sleeve 545 is
opened and the
acidifying hole 540 is opened to start acidifying the first layer, at this
time, the flow channel of
the single flow controlling water sieve pipe connected to the outside is
blocked by the piston,
and the acidifying fluid can enter the formation through only the acidifying
hole 540 of the
uniflow ball fracturing sliding sleeve 53 to complete acidifying and dredging
the formation.
After the acidification is completed, the impaction is stopped, the second
support spring 544
abuts upwards against the sliding block 543, and the slide block 543 pushes
the inner sliding
sleeve 545 and the ball seat 546 to be repositioned, and the ball seat 546
closes the sliding sleeve
again under the action of the second support spring 544.
When it is necessary to acidify the upper layer (acidifying layer), a suitably
sized acid
resistant soluble ball is thrown onto the ball seat 546 of the ball fracturing
sliding sleeve 53 of
the upper layer, and other operations are the same as those of the
acidification operation of the
lower layer.
The channel conversion type regulating flow and controlling water segmented
acidifying
pipe string 50 can increase the number of acidifying layers by adding an
isolation packer 54, a
single flow controlling water sieve pipe and a ball fracturing sliding sleeve
53 with different
sizes of the ball seat 546, so as to realize fine layering. In production, oil
and gas passes forwards
through filtration of a sieve mesh segment of the single flow controlling
water sieve pipe to enter
the annulus with the base pipe 522, then pushes the piston, flows through the
regulating flow
and controlling water member 534 (AICD) via the communication hole of the
overflowing
sleeve to enter the oil pipe and finally reach the ground surface, and realize
production by water
control and gas stabilization.
In this embodiment, the channel conversion type regulating flow and
controlling water
Date Recue/Date Received 2022-05-09
26
segmented acidifying pipe string 50 has the following advantages:
(1) The layered acidification function is realized by three or more layers,
and the
acidification effect is better.
(2) The layered regulating flow and controlling water function is realized by
three or more
layers, and the regulating flow and controlling water has strong pertinence
and good effect.
(3) The acidifying channel and the water controlling channel are completely
separated, the
displacement through segmented acidification is large, acidification is more
efficient, the fluid
enters the regulating flow and controlling water device through the sieve pipe
during water
control, and the pertinence of water control is strong.
(4) The multi-layer acid fracturing and water control operation is realized by
one-trip pipe
string 50, thus construction time is shortened and operation efficiency is
improved.
(5) The integration of segmented acidification and regulating flow and
controlling water is
realized.
Referring to FIGs. 20 to 26, in another embodiment of the present disclosure,
the regulating
flow and controlling water acidification device is a unidirectional valve type
regulating flow and
controlling water acidifying pipe string 60. The regulating flow and
controlling water sieve pipe
62 is a one-way valve type controlling water sieve pipe 62. The single flow
mechanism is a two-
stage fracturing sliding sleeve 63 connected to the lower end of the one-way
valve type
controlling water sieve pipe 62.
The one-way valve type controlling water sieve pipe 62 and the two-stage
fracturing sliding
sleeve 63 constitute a regulating flow and controlling water acidification
assembly. The
unidirectional valve type regulating flow and controlling water acidifying
pipe string 60 includes
a top packer 61, a plurality of the regulating flow and controlling water
acidification assemblies,
an isolation packer 64 connected between two adjacent regulating flow and
controlling water
acidification assemblies, a wellbore isolation valve 65, and a two-stage
floating shoe 66.
As shown in FIG. 20, schematically an example is given that the acidifying
layer is divided
into upper and lower acidifying layers. The complete set of unidirectional
valve type regulating
flow and controlling water acid fracturing pipe string 60 is an outer pipe
string mainly composed
of the following tools. The outer pipe string 60 includes, from bottom to top,
the top packer 61,
the one-way valve type controlling water sieve pipe 62, the two-stage
fracturing sliding sleeve
63, the isolation packer 65, and the two-stage floating shoe 66.
In this embodiment, the one-way valve type controlling water sieve pipe 62 is
composed of
the sieve mesh portion 624 and the regulating flow and controlling water
member 620. The
(adaptive) regulating flow and controlling water member 631 (AICD) is
installed on the sieve
Date Recue/Date Received 2022-05-09
27
mesh base pipe 622. The upper end of the base pipe 622 is fixedly connected
with a collar 621.
As shown in FIG. 15, the sieve mesh portion 624 is mainly composed of a three -
layer
structure, and the outermost side is a circular hole outer protection sheath
20. The outer
protection sheath 20 protects the filter layer and ensures the strength and
reliability of the sieve
mesh. The second through fifth layers in the middle are filter layers. In the
filter layers, the
second and fourth layers are precise filter screens 21 and 23 (sand prevention
and filtering
function). The third and fifth layers are precision flow guiding meshes 22 and
24 (to guide the
flow of incoming fluid). The sixth layer in the inner side is a supporting
layer 25, which ensures
a sufficient circulation area between the filter layer and the base pipe 622.
The supporting layer
25, the filter layer and the base pipe 522 are extrusion forged by extrusion
forging process, which
increases the strength by 74% while reducing the cost compared with the
conventional sieve
pipe.
As shown in FIGs. 21 and 22, the upper end of the outer protection sheath 20
is fixedly
connected with an upper end ring 623 that fixedly sleeves outside the base
pipe 622. The lower
end of the outer protection sheath 20 is connected to the upper end of an
outer pipe 626 by a
mating plug 625. A flow guide channel is formed between the sieve mesh portion
624 and the
base pipe 622. The mating plug 625 is fixedly sleeved outside the base pipe
622, and a channel
communicating the regulating flow and controlling water space with the sieve
mesh portion 624
(flow guide channel) is formed between the mating plug 525 and the base pipe
622. The lower
end of the outer pipe 626 is fixedly sleeved outside the lower joint 632, and
is fixedly connected
by a set screw 634 to prevent rotation. The lower end of the outer pipe 626 is
also sealed from
the lower joint 632 through the sealing ring 635.
The base pipe 622 includes an upper base pipe 6220 and a lower base pipe 628.
A lower
end of the upper base pipe 6220 and the upper end of the lower base pipe 628
are fixedly
connected by an intermediate joint. The sieve mesh portion 624 is disposed
outside the upper
base pipe 6220, and at least a majority of the regulating flow and controlling
water portion 620
is disposed on the lower base pipe 628. The unidirectional component 630 is
looped between the
outer pipe 626 and the (lower) base pipe 622 to cause the regulating flow and
controlling water
space to be formed axially into a first axial space communicating with the
sieve mesh portion
624 and a second axial space communicating with the regulating flow and
controlling water
member 631 that are spaced from each other. The lower end of the lower base
pipe 628 is
externally screwed to the inner side of the lower joint 632, and is provided
with a sealing ring
633 for sealing. The lower base pipe 628 constitutes a mounting base of the
regulating flow and
controlling water member 631. The regulating flow and controlling water member
631 is the
Date Recue/Date Received 2022-05-09
28
plate-type regulating flow and controlling water member or the tapered
regulating flow and
controlling water member in the above-described embodiment.
As shown in FIGs. 25, 26 and 27, the unidirectional component 630 includes a
first
unidirectional ball seat 6301 and a second unidirectional ball seat 6302 which
are connected
oppositely in an axial direction. The inner and outer sides of the first
unidirectional ball seat
6301 and the second unidirectional ball seat 6302 (in the radial direction)
are provided with a
sealing ring 629, which form sealing with the outer wall of the lower base
pipe 628 and the inner
wall of the outer pipe 626. In the flowing direction of the formation fluid,
the first unidirectional
ball seat 6301 is disposed upstream of the second unidirectional ball seat
6302, the first
unidirectional ball seat 6301 has a first number of first channels 6311
distributed in a
circumferential direction. The second unidirectional ball seat 6302 has more
than a first number
of second channels 6321 distributed in the circumferential direction.
Specifically, the first number of second channels 6321 are disposed in one-to-
one alignment
with the first plurality of first channels 6311 in the axial direction, and
the remaining number of
second channels 6321 are staggered from the first channels 6311. In the first
channels 6311 and
the second channels 6321 which are aligned in the axial direction, the end
portions of the first
channels 6311 and the second channels 6321 that are relatively buckled are
provided with ball
seats 6312 and 6322 respectively, and a blocking valve ball 636 is arranged in
the ball seats 6312
and 6322 which are relatively buckled. The number of the second channels 6321
may be twice
that of the first channels 6311. The first unidirectional ball seat 6301 and
the second
unidirectional ball seat 6302 are connected oppositely, and an abutting gap
may exist
therebetween. The axial length of the abutting gap is smaller than the
diameter of the blocking
valve ball 636, preferably smaller than the radius of the blocking valve ball
636.
The blocking valve ball 636 is a steel ball and is movable in the axial
direction. In the
aligned first and second channels 6311, 6321, the two ball seats 6312, 6322
constitute a
movement space of the blocking valve ball 636, the blocking valve ball 636
moves forward to
block the first channel 6311, the first unidirectional ball seat 6301 is
completely blocked and the
unidirectional component 630 is closed. The blocking valve ball 636 moves
rearward to block a
portion of the number (the first number) of second channels 6321, the
remaining number of
second channels 6321 are not blocked and the unidirectional component 630 is
opened.
During acidification, the check valve (unidirectional component 630) is
closed, and the
acidifying fluid cannot enter the formation through the sieve pipe, but only
through the two-
stage fracturing sliding sleeve 63. During production, the check valve 630 is
opened, and the
fluid flows from the filter screen through the check valve (unidirectional
component 630), and
Date Recue/Date Received 2022-05-09
29
finally enters the oil pipe through the regulating flow and controlling water
member 631 (AICD)
to reach the ground surface. The unidirectional component 630 of the check
valve structure has
left and right ball seats 6312 and 6322 with different numbers of holes, and
the blocking valve
ball 636 cannot leave the left and right ball seats 6312 and 6322. When acid
fracturing is
performed, as shown in the acid fracturing in FIG. 26, the balls 636 all fall
into the left ball seat
6312, at this time the flow channel is completely blocked by the balls 636, so
that the acidifying
fluid can not enter the formation. As production proceeds, as shown in
production figure FIG.
27, the blocking valve balls 636 all fall into the right ball seat 6322, but
the number of the holes
on the right side is great than the number of the balls 636. When the flow
channel is opened, the
formation oil and gas enters the oil pipe through the regulating flow and
controlling water
member 631 (a flow regulating and gas stabilization member) to reach the
ground surface.
In this embodiment, as shown in FIGs. 23 and 24, the two-stage fracturing
sliding sleeve
63 includes: a sliding sleeve body 651; an upper valve seat sliding sleeve 652
slidably sleeved
in the sliding sleeve body 651, and a lower valve seat sliding sleeve 653
located below the upper
valve seat sliding sleeve 652. The sliding sleeve body 651 is provided with
the acidifying hole
6510. The inner diameter of the lower valve seat sliding sleeve 653 is smaller
than the inner
diameter of the upper valve seat sliding sleeve 652. Accordingly, an upper
valve ball 659 has a
larger diameter than that of a lower valve ball 653. The lower valve ball 653
can be seated on
the lower valve seat sliding sleeve 653 through the upper valve seat sliding
sleeve 652, so as to
block the lower valve seat sliding sleeve 653. The lower valve ball 653 is
thrown to open the
acidifying hole 6510, which may be referred to as an acidifying ball. The
upper valve ball 659
is thrown to close the acidifying hole 6510, which may be referred to as a
closing ball. The lower
valve seat sliding sleeve 653 is positioned by the shearing pin 654 at a
position where the
acidifying hole 6510 is blocked. The upper valve seat sliding sleeve 652 is
positioned above the
lower valve seat sliding sleeve 653 by the shearing pin 6511. After being
blocked by a throw
ball, the lower valve seat sliding sleeve 653 can be pushed by pressure to a
position where the
acidifying hole 6510 is opened. After being blocked by a throw ball, the upper
valve seat sliding
sleeve 652 can be pushed by pressure to a position where the acidifying hole
6510 is re-blocked.
The upper and lower ends of the upper valve seat sliding sleeve 652 are both
provided with
sealing rings which are in sealing contact with the inner wall of the sliding
sleeve body 651. The
upper and lower ends of the lower valve seat sliding sleeve 653 are both
provided with sealing
rings which are in sealing contact with the inner wall of the sliding sleeve
body 651.
The two-stage fracturing sliding sleeve 63 controls the opening and closing of
the acidifying
hole 6510 through the upper and lower valve seat sliding sleeves 653 with
different inner
Date Recue/Date Received 2022-05-09
30
diameters, to open the lower valve seat sliding sleeve 653, move down the
lower valve seat
sliding sleeve 653 and open the acid fracturing hole. The upper valve seat
sliding sleeve 652 is
opened and is moved down, and the acid fracturing hole is closed again. For
example, the lower
valve ball 653 (which is an acid resistant soluble ball) has an outer diameter
of 0.1 in (2.54 mm),
which is smaller than the minimum inner diameter of upper valve seat sliding
sleeve 652, so as
to pass through the upper valve seat sliding sleeve 652.
The lower end of the sliding sleeve body 651 is connected with a lower joint
657. A sealing
ring 656 is provided between the lower end of the sliding sleeve body 651 and
the lower joint
657. A part of the lower joint 657 that extends into the lower end of the
sliding sleeve body 651
has a limiting end 6571. The lower valve seat sliding sleeve 653 is axially
limited by the lower
joint 657 when being pushed by the throw ball into contact with the limiting
end 6571. The upper
valve seat sliding sleeve 652 is axially limited by the lower valve seat
sliding sleeve 653 when
being pushed by the throw ball into contact with the lower valve seat sliding
sleeve 653, and the
acidifying hole 6510 is re-blocked.
In the application of the unidirectional valve type regulating flow and
controlling water
acidifying pipe string 60, the following operation mode is adopted:
first, the pipe string 60 is run to a predetermined position by using a drill
stem connection
special running tool, and automatic grouting is performed by the wellbore
isolation valve 65
during the run-in process, wherein the fluid enters the inside of the pipe
string 60 through the
hole of the wellbore isolation valve 65, to maintain the pressure balance
inside and outside the
pipe string 60. After the pipe string 50 is run in place, the bal closes the
wellbore isolation valve
65. At this time, the forward two-stage floating shoe 66 can be opened, and
the reverse two-
stage floating shoe 66 is not connected.
After the wellbore isolation valve 65 is closed, the isolation packer 64 is
set step by step.
The oil pipe impacts the setting forwards, and after the setting is completed,
the isolation packer
64 is sealed. Through annulus impaction, and if the pressure is stable, the
sealing is qualified;
then a top hanging packer is set by a special setting tool, and is annularly
sealed and hang after
the setting is completed. The sleeve is impacted to check whether the top
packer 61 is qualified,
and after the sealing of the top packer 61 is qualified, the setting tool is
annularly impacted or
forward released.
When acidifying the lower layer (acidifying layer), the acid resistant soluble
ball is thrown
onto the lower valve seat sliding sleeve 653 of the lower one of the two-stage
fracturing valve
seat. The oil pipe is impacted, the lower valve seat sliding sleeve 653 shears
the shearing pin,
the lower valve seat sliding sleeve 653 moves downwards, the acidifying hole
6510 is opened,
Date Recue/Date Received 2022-05-09
31
to start acidifying the first layer (a lower acidifying hole), at this time,
the flow channel of the
one-way valve type controlling water sieve pipe 62 connected to the outside is
closed, and the
acidifying fluid can enter the formation through only the acidifying hole 6510
of the two-stage
fracturing sliding sleeve 63 to complete acidifying and dredging the
formation. After completion
of acidification, the impaction is stopped, and a suitably sized acid
resistant soluble ball is thrown
onto the upper valve seat sliding sleeve 652 of the lower one of the two-stage
fracturing valve
seat. The upper valve seat sliding sleeve 652 shears the shearing pin and
moves downwards to
be positioned at the upper end of the lower valve seat sliding sleeve 653,
with the upper valve
seat sliding sleeve 652 just closing the acidifying hole 6510.
When it is necessary to acidify the upper layer (acidifying layer), the
operation is
completely the same as that of the acidification operation of the lower layer.
The unidirectional valve type regulating flow and controlling water acidifying
pipe string
60 can increase the number of acidifying layers by adding an isolation packer
64, a one-way
valve type controlling water sieve pipe 62 and a two-stage fracturing sliding
sleeve 63 with
different ball seat sizes, so as to realize fine layering.
In production, oil and gas passes forwards through filtration of a sieve mesh
segment of the
one-way valve type controlling water sieve pipe 62 to enter the annulus with
the base pipe, then
flows through the controlling water device (AICD) via the check valve to enter
the oil pipe and
finally reach the ground surface, and realize production by water control and
gas stabilization.
In this embodiment, the unidirectional valve type regulating flow and
controlling water
acidifying pipe string 60 has the following advantages:
(1) The layered acidification function is realized by three or more layers,
and the
acidification effect is better.
(2) The multi-layer acid fracturing is realized by one trip, thus construction
time is
shortened and operation efficiency is improved.
(3) The integration of acidification and controlling water is realized.
(4) The tool totally adopts mechanical structure, to realize reliable
performance.
(5) The number of fracturing segments is increased in one segment, and the
pertinence of
acid fracturing in the segment is increased.
(6) The check valve is used to open and close the water controlling sieve pipe
62 with high
reliability.
Referring to FIGs. 28 to 33, in another embodiment of the present disclosure,
the regulating
flow and controlling water acidification device is an adaptive regulating flow
and controlling
water acidifying pipe string 70. The regulating flow and controlling water
sieve pipe 73 is an
Date Recue/Date Received 2022-05-09
32
adaptive regulating flow and controlling water sieve pipe 73. The single flow
mechanism 74 is
a single flow fracturing pass assembly 74 connected to the upper end of the
regulating flow and
controlling water sieve pipe 73. The single flow fracturing pass assembly 74
and the adaptive
regulating flow and controlling water sieve pipe 73 constitute a regulating
flow and controlling
water acidification assembly.
The adaptive regulating flow and controlling water acidifying pipe string 70
includes a top
packer 71 and a plurality of the regulating flow and controlling water
acidification assemblies;
wherein an expansion packer 72 is arranged above and below each of the
regulating flow and
controlling water acidification assemblies. The adaptive regulating flow and
controlling water
sieve pipe 73 is further provided with a centralizer 75.
The integrated adaptive regulating flow and controlling water sieve pipe 73 is
composed
mainly of a sieve mesh portion 733 and an adaptive regulating flow and
controlling water
portion. The adaptive regulating flow and controlling water member 737 is
installed on the base
pipe of the adaptive regulating flow and controlling water portion. The upper
end of the base
pipe is fixedly connected with a collar 731.
The adaptive regulating flow and controlling water sieve pipe 73 includes a
sieve mesh
base pipe 732 and a water controlling base pipe 736. The sieve mesh base pipe
732 and the water
controlling base pipe 736 are connected to form the base pipe. A flow guide
channel 734 is
formed between the sieve mesh portion 733 and the base pipe 732. A connecting
component 735
is fixedly connected outside the base pipe. The connecting component 735 is
fixedly connected
with the lower end of the outer protection sheath 20 and the upper end of the
outer pipe 738. The
connecting component 735 is provided with a communication channel which
communicates the
flow guide channel 734 with the regulating flow and controlling water space.
As shown in FIG. 15, the sieve mesh portion 733 is mainly composed of a three-
layer
structure, and the outermost side is a circular hole outer protection sheath
20. The outer
protection sheath 20 protects the filter layer and ensures the strength and
reliability of the sieve
mesh. The second through fifth layers in the middle are filter layers. In the
filter layers, the
second and fourth layers are precise filter screens 21 and 23 (sand prevention
and filtering
function). The third and fifth layers are precision flow guiding meshes 22 and
24 (to guide the
flow of incoming fluid). The sixth layer in the inner side is a supporting
layer 25, which ensures
a sufficient circulation area between the filter layer and the base pipe. The
supporting layer 25,
the filter layer and the base pipe are extrusion forged by extrusion forging
process, which
increases the strength by 74% while reducing the cost compared with the
conventional sieve
pipe.
Date Recue/Date Received 2022-05-09
33
The water controlling base pipe 736 is connected to the inner wall of the
outer pipe 738
respectively at both axial ends of the regulating flow and controlling water
space. The water
controlling base pipe 736 is further provided with a wall clamping channel
upstream of the
regulating flow and controlling water space. A communication annulus is
further arranged
between the upper end of the water controlling base pipe 736 and the
connecting component.
The communication annulus is communicated between the communication channel
and the wall
clamping channel. A recessed portion between the upper and lower ends of the
water controlling
base pipe 736 and the outer pipe 738 form the regulating flow and controlling
water space. The
regulating flow and controlling water member 737 is installed on the wall of
the recessed portion.
The lower end of the water controlling base pipe 736 is also provided with a
lower joint 739.
The adaptive regulating flow and controlling water portion is composed of
three portions,
namely, the water controlling base pipe 736, the outer pipe 738 and the
regulating flow and
controlling water member 737 which serves as an adaptive regulating flow core
control member.
The regulating flow and controlling water member 737 is connected to the upper
portion of the
central hole of the water controlling base pipe 736 by welding or screw
thread. The adaptive
regulating flow and controlling water member 737 is connected to the dedicated
water
controlling base pipe 736 by means of thread plug, and is installed on the
central hole of the
water controlling base pipe 736 that is in communication with the regulating
flow and controlling
water space to ensure the connection flexibility of the tool.
In this embodiment, as shown in FIGs. 29 and 30, the single flow fracturing
pass assembly
74 includes an outer cylinder 756, and an inner pipe body 752 fixedly sleeved
in the outer
cylinder 756. The outer cylinder 756 is provided with the acidifying hole and
a micro check
valve 755 disposed in the acidifying hole. The interior of the inner pipe body
752 is formed as a
central passage. The central passage has an outflow hole 7521. The outflow
hole 7521 is in
communication with an intermediate annulus between the inner pipe body 752 and
the outer pipe
body 756. In the intermediate annulus, a rubber sealing sleeve 758 is further
arranged for
covering the outflow hole 7521 that is fitted and sleeved outside the inner
pipe body 752. The
rubber sealing sleeve 758 is capable of opening the outflow hole 7521 when the
pressure within
the central passage exceeds a first predetermined pressure. The upper end of
the outer cylinder
756 is externally threaded to the lower end of an upper joint 751, and is
sealed by a sealing ring
754. The upper end of the inner pipe body 752 is fixedly connected within the
upper joint 751,
and is sealed by a sealing ring 753. Similarly, the lower end of the outer
cylinder 756 fixedly
sleeves outside the upper end of the lower joint 762, and is sealed by a
sealing ring 760. The
lower end of the inner cylinder 752 fixedly sleeves inside the upper end of
the lower joint 762,
Date Recue/Date Received 2022-05-09
34
and is sealed by a sealing ring 761.
As shown in FIG. 31, the micro check valve 755 includes a valve body 7551
fixed in the
acidifying hole, a baffle plate 7552 fixed to an outer end of the valve body
7551 in a radial
direction, a valve ball 7555 located in the valve body 7551, and a spring 7553
located between
the valve ball 7555 and the baffle plate 7552. The valve body 7551 has a valve
body seat blocked
by the valve ball 7555 at a radially inner end. In the valve body 7551, a
guiding body 7554 is
further provided. The guiding body 7554 is fitted to the inner wall of the
valve body 7551, is a
motion guide of the valve ball 7555 and is a supporting point of the spring
7553 to facilitate the
installation of the spring 7553. The spring 7553 is installed between the
guiding body 7554 and
the baffle plate 7552. The valve ball 7555 is seated between the valve body
seat and the guiding
body 7554, and is abutted upwards by the spring 7553.
Specifically, the micro check valve is composed of a baffle plate 7552, a
spring 7553, a
guiding body 7554, a valve body seat, and a steel ball 7555, to form a
relatively simple overall
structure. The whole valve body 7551 is externally threaded, and can be
further installed on the
outermost outer cylinder body of the single flow fracturing pass assembly 74
through threaded
connection, so that the whole structure is compact and flexible, and the
reliability is high. The
micro check valve is a low-pressure closed state during the tool lowering
process, and the
opening pressure is set at 0.1-0.2 MPa.
During acidification, an acidifying fracturing fluid is injected into the
formation at an
injection pressure being greater than 0.2 MPa. The check valve can fully open
(acidifying hole).
The minimum passing diameter of the whole check valve is 5 mm, then under the
driving
pressure of 1 MPa, 0.5 m3 or more fracturing fluid can pass through a single
micro check valve
per minute, which can meet the technical requirement of large-scale acidifying
fracturing.
When in production, the formation pressure acts on the micro check valve 755.
The micro
check valve 755 can block a differential pressure difference of 60 MPa through
face seal between
the steel ball 7555 and the valve body seat, ensuring the closing of the micro
check valve 755,
so that the fluid must flow through the integrated adaptive regulating flow
and controlling water
sieve pipe 73 to be subjected to regulating flow and controlling liquid and
then enter the
production pipe string 70. The entire micro check valve is designed
integrally, has no moving
parts and has a high use reliability, which can meet the requirements of the
application.
As shown in FIGs. 31 and 32, the single flow fracturing pass assembly 74
performs double
steel seal through the micro check valve 755 and the rubber sealing sleeve
758. During
acidification, the rubber sealing sleeve 758 is impacted inside the pipe to be
pushed outwards to
be expanded and opened, and the micro check valve 755 is further pushed to be
opened, so as to
Date Recue/Date Received 2022-05-09
35
achieve that the whole single flow fracturing pass assembly 74 is opened, and
the acidifying
channel is opened to realize the communication between the inside and the
outside of the pipe
string 70. After the impaction is stopped, the micro check valve 755 is reset
under the action of
the spring 7553, and the rubber sealing sleeve 758 is restored to its original
state to close the
outflow hole again. The single flow fracturing pass assembly 74 plays the role
of opening and
closing and sealing mainly by the micro check valve 755 and the rubber seal
sleeve 758.
In order to install the rubber sealing sleeve 758, a fixing sleeve 757 further
sleeves outside
the inner pipe body 752. The upper end of the fixing sleeve 757 is threaded
outside the inner
pipe body 752. The lower end of the fixing sleeve 757 is provided with a
sealing ring 759 which
is fitted and sleeves on the outer wall of the inner pipe body 752. A space
for accommodating
the rubber sealing sleeve 758 is formed between the upper and lower ends of
the fixing sleeve
757 and the outer wall of the inner pipe body 752. The fixing sleeve 757 is
provided with a
mounting step at the upper end of the space, into which an upper end 7581 of
the rubber sealing
sleeve 758 is inserted, thereby axially limiting the rubber sealing sleeve
758. The fixing sleeve
757 is further provided with a connection through hole 7571 on the outer wall
of the space. The
connection through hole communicates the space with an outer annulus (an
annulus between the
outer cylinder and the inner pipe body).
The wall thickness of the rubber sealing sleeve 758 is in a stepped manner in
the axial
direction from the upper end to the lower end. The stepped wall thickness at
the upper side is
greater than that at the lower side. As shown in FIG. 32, the upper end of the
rubber sealing
sleeve 758 has a thickness greater than that of the middle portion 7582 and
the lower end 7583,
wherein the thickness of the lower end 7583 is the smallest. The rubber
sealing sleeve 758 has
an annular sealing structure, and the thickness of the rubber is arranged in
steps, and such
configuration is mainly adapted to the manner in which the rubber seal is
opened from the
outside to the inside step by step when the acidifying fluid is injected into
the inside, so as to
ensure smooth opening of the rubber seal assembly during acid injection.
During production, the
rubber sealing sleeve 758 receives the sealing pressure in a forward
direction. The formation
pressure ensures that the rubber sealing sleeve 758 can closely adhere to the
wall surface of the
inner pipe body, so as to ensure that leakage is caused due to inadequate
sealing during gas
production, which affects the working effect of the regulating flow and
controlling water device.
During acidification, the single flow fracturing pass assembly 74 is a main
flow channel.
Most of the acidifying fracturing fluid enters the formation through the flow
channel pipe string
70 of the single flow fracturing pass assembly 74, and less acidifying fluid
enters the formation
through the adaptive regulating flow and controlling water sieve pipe 73.
During production, the
Date Recue/Date Received 2022-05-09
36
fluid pushes the single flow fracturing pass assembly 74 to be closed, and the
formation fluid
must be regulated by the adaptive regulating flow and controlling water device
and then enters
the oil pipe to reach the ground surface.
In the application of the adaptive regulating flow and controlling water
acidifying pipe
.. string 70, the following operation mode is adopted:
first, the pipe string 70 is run to a predetermined position by using a drill
stem connection
special running tool, during the running-in process, due to the communication
between the inside
and the outside of the adaptive regulating flow and controlling water sieve
pipe 73, the liquid
can enter the inside of the pipe string 70 through the adaptive regulating
flow and controlling
.. water sieve pipe 73, so as to keep the balance between the inside and the
outside of the pipe, and
no extra tools or no special operations are required.
After the tool is in place, a top hanging packer is set by a special setting
tool, and is
annularly sealed and hang after the setting is completed. The sleeve is
impacted to check whether
the top packer 71 is qualified, and after the sealing of the top packer 71 is
qualified, the setting
.. tool is annularly impacted or forward released.
Segmented acidification: oil pipe impaction and pumping acidifying fracturing
fluid
system. As the pressure of the inner pipe string 70 increases, the single flow
fracturing pass
assembly 74 is opened, and the acidifying fracturing fluid enters the
formation through the single
flow fracturing pass assemblies 74 arranged in the front, middle, and rear
portions of the entire
set of adaptive regulating flow and controlling water completion pipe string
70, respectively, to
realize segmented acidification of the corresponding reservoirs respectively.
At this time,
although the adaptive regulating flow and controlling water sieve pipe 73
communicates
internally and externally, the throughput of the single flow fracturing pass
assembly 74 is much
better than that of the adaptive regulating flow and controlling water sieve
pipe 73, and in the
process of fracturing, the displacement is large and the pressure in the pipe
is relatively high,
most of the acidifying fracturing fluid enters the formation through the
single flow fracturing
pass assembly 74, so as to realize segmented acidifying and fracturing of the
reservoir, and
dredging the formation. After acidification is completed, impaction is
stopped, and the single
flow fracturing passing sliding sleeve is closed again under the action of
formation pressure.
The adaptive regulating flow and controlling water acidifying pipe string 70
may increase
and optimize the number and location of acidifying layers by increasing the
number and location
of oil-in expansion packers 72, the adaptive regulating flow and controlling
water sieve pipe 73,
and the single flow fracturing pass assembly 74, to achieve fine layering.
In production, oil and gas passes forwards through filtration of a sieve mesh
segment of the
Date Recue/Date Received 2022-05-09
37
adaptive regulating flow and controlling water sieve pipe 73 to enter the
annulus with the base
pipe 522, then flows through the regulating flow and controlling water member
737 (AICD) of
the adaptive regulating flow and controlling water well completion device to
enter the oil pipe
and finally reach the ground surface, and realize production by water control
and gas
stabilization.
In this embodiment, the adaptive regulating flow and controlling water
acidifying pipe
string 70 has the following advantages:
(1) Integrated design, the adaptive regulating flow and controlling water
completion pipe
string 70 has a simple structure and high reliability.
(2) The adaptive regulating flow and controlling water sieve pipe 73 has a
simple structure,
no moving parts and a long service life.
(3) The expansion packer 72 is adopted to realize the segmentation of the
reservoir, without
the need for packer setting and checking, which increases the safety of the
whole process and
the simplicity of construction.
(4) The adaptive regulating flow and controlling water sieve pipe 73
communicates
internally and externally. During the tool running, the internal and external
pressure of the pipe
string 70 are balanced, providing high safety.
(5) The single flow fracturing pass assembly 74 is simple in structure, and
the opening and
closing processes are simple and reliable.
(6) The layered acidification function is realized by three or more layers,
and the
acidification effect is better.
(7) The acidifying channel and the water controlling channel are completely
separated, the
displacement through segmented acidification is large, acidification is more
efficient, the fluid
enters the regulating flow and controlling water device through the sieve pipe
during water
control, and the pertinence of water control is strong.
(8) The multi-layer acid fracturing and water control operation is realized by
one-trip pipe
string 70, thus construction time is shortened and operation efficiency is
improved.
(9) The multi-layer acid fracturing and water control operation is realized by
one-trip pipe
string 70, thus construction time is shortened and operation efficiency is
improved.
(10) The integration of segmented acidification and regulating flow and
controlling water
is realized.
In conclusion, with the regulating flow and controlling water acidification
well completion
device for an oil and gas well and a matching pipe string 70 provided in the
disclosure, after the
segmented acid fracturing production and water controlling integrated pipe
string 70 system is
Date Recue/Date Received 2022-05-09
38
run by one-time operation, the expansion of the isolation packer realizes the
segmentation of the
horizontal interval, so as to realize the reservoir segmentation and the acid
fracturing of different
segments, and realize the segmented acid fracturing function. After acid
fracturing is completed,
each horizontal segment communicates with the reservoir. The fluid outside the
reservoir may
enter the production pipe string 70 by selecting different types of (adaptive)
regulating flow and
controlling water sieve pipes 73 according to the different process techniques
employed. In the
process of passing through the single flow controlling water sieve pipe 73 or
the one-way valve
type controlling water sieve pipe 73, or the adaptive water controlling sieve
pipe 73, by an inner
wall surface swirl flow channel structure and a flat plate flow channel
structure of the regulating
flow and controlling water member 737, resistance is applied twice to the
inflow fluid so as to
control inflow velocity of fluids in different phase states, so as to achieve
the goals of unimpeded
gas production, preferential oil phase production, controlled water phase
production, and realize
the purpose of regulating flow and controlling water, which solves the
difficult problem of the
segmented acid fracturing production and water controlling integrated tool
device and the
matching technology for water-bearing oil and gas wells, tight oil and gas
reservoirs and
complex high-acid oil and gas reservoirs.
The tool device and the pipe string 70 system that integrate the segmented
acid fracturing
completion and the production and water control functions are run in one-pass
operation, so as
to overcome the problems that the general effect of acid fracturing and
increasing production in
.. the long horizontal wellbore is not obvious, the gas production of
different horizontal segments
is not uniform after a period of segmented acid fracturing production, and the
wellbore is easy
to be flooded by edge and bottom water coning.
Through one-pass operation of running the pipe string 70 while achieving acid
fracturing,
the original pipe string 70 has the function of production, and has the effect
of controlling the
water and suppressing the edge and bottom water coning along the horizontal
wellbore, so as to
reduce the operation process and save the process cost, to prevent the
production of toxic gas
and difficult problems in complex oil and gas well completion process to the
maximum extent,
ensure the safety of production operation, which achieves the maximum recovery
in the control
region of the horizontal wells of various edge-bottom water oil and gas
reservoirs and complex
highly difficult oil and gas reservoirs, and realize the completion and
production optimization
of the oil and gas wells.
Any numerical value referred to herein includes all values of a lower value
and an upper
value that are incremented by one unit from a lower limit value to an upper
limit value, with an
interval of at least two units between any lower value and any higher value.
For example, if it is
Date Recue/Date Received 2022-05-09
39
stated that the number of components or process variables such as temperature,
pressure, time,
etc., have a value from 1 to 90, preferably from 20 to 80, more preferably
from 30 to 70, the
purpose is to illustrate that the equivalents such as 15 to 85, 22 to 68, 43
to 51, 30 to 32 are also
explicitly recited in the specification. For values smaller than 1, one unit
is suitably considered
to be 0.0001, 0.001, 0.01, 0.1. These are merely intended to be explicitly
expressed examples,
and it may be considered that all possible combinations of numerical values
enumerated between
the lowest value and the highest value are explicitly set forth in a similar
manner in this
specification.
Unless otherwise stated, all ranges include end points and all numbers between
the end
points. The "about" or "approximate" used with the range is suitable for both
end points of the
range. Thus, "about 20 to 30" is intended to cover "about 20 to about 30,"
including at least the
indicated end points.
All articles and references disclosed, including patent applications and
publications, are
incorporated herein by reference for all purposes. The term "consisting
essentially of' to describe
a combination should include the elements, components, parts or steps
determined and other
elements, components, parts or steps that do not substantially affect the
substantially novel
features of the combination. The use of the terms "comprising" or "including"
to describe
combination of the elements, components, parts or steps herein also
contemplates embodiments
that consist essentially of such elements, components, parts or steps. The use
of the term "may"
herein is intended to illustrate that any of the described attributes that may
be included are
optional.
The plurality of elements, components, parts or steps can be provided by a
single integrated
element, component, part or step. Alternatively, the single integrated
element, component, part
or step may be divided into separate multiple elements, components, parts or
steps. A disclosed
"a" or "an" used to describe an element, a component, a part or a step does
not mean to exclude
other elements, components, parts or steps.
It should be understood that the above description is for purposes of
illustration and not for
purposes of limitation. Many embodiments and many applications other than the
examples
provided will be apparent to those skilled in the art from reading the above
description.
Accordingly, the scope of the present teachings should not be determined with
reference to the
above description, but should be determined with reference to the appended
claims and the full
scope of equivalents owned by these claims. The disclosure of all articles and
references,
including patent applications and publications, is incorporated herein by
reference for purposes
of completeness. The omission of any aspect of the subject matter disclosed
herein in the
Date Recue/Date Received 2022-05-09
40
foregoing claims is not intended to waive the subject matter and the inventor
should not be
deemed to have considered the subject matter as a part of the disclosed
subject matter.
Date Recue/Date Received 2022-05-09
