U.S. patent application number 12/330773 was filed with the patent office on 2009-06-11 for guide tool for guiding downhole tools through wellbore restrictions.
Invention is credited to Geir Owe Egge, Henning Hansen, Terje Wilberg.
Application Number | 20090145596 12/330773 |
Document ID | / |
Family ID | 40720423 |
Filed Date | 2009-06-11 |
United States Patent
Application |
20090145596 |
Kind Code |
A1 |
Hansen; Henning ; et
al. |
June 11, 2009 |
GUIDE TOOL FOR GUIDING DOWNHOLE TOOLS THROUGH WELLBORE
RESTRICTIONS
Abstract
A guide tool for mounting onto a downhole tool for use in a
wellbore penetrating subsurface formations is provided. The guide
tool has a bull nose. The bull nose has a first section with an end
for sealing against and engaging a lower end of the downhole tool
and a second section axially deflectably coupled to the first
section.
Inventors: |
Hansen; Henning; (Alicante,
ES) ; Egge; Geir Owe; (Stavanger, NO) ;
Wilberg; Terje; (Sandnes, NO) |
Correspondence
Address: |
RICHARD A. FAGIN
P.O. BOX 1247
RICHMOND
TX
77406-1247
US
|
Family ID: |
40720423 |
Appl. No.: |
12/330773 |
Filed: |
December 9, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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61012479 |
Dec 10, 2007 |
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12330773 |
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61012479 |
Dec 10, 2007 |
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Current U.S.
Class: |
166/117.5 |
Current CPC
Class: |
E21B 23/14 20130101 |
Class at
Publication: |
166/117.5 |
International
Class: |
E21B 23/00 20060101
E21B023/00; E21B 23/14 20060101 E21B023/14 |
Claims
1. A guide tool for use in a wellbore penetrating subsurface
formations, the guide tool having a bull nose, said bull nose
having a first section with an end for sealing against and engaging
a lower end of a downhole tool and a second section coupled to the
first section such that an axis of the second section is
deflectable to an axis of the first section.
2. The guide tool of claim 1, wherein the second section is coupled
to the first section by an indexing system that provides indexed
deflection.
3. The guide tool of claim 2, wherein the indexing system is
mechanically-activated.
4. The guide tool of claim 2, wherein the indexing system is
pressure-activated.
5. The guide tool of claim 1, further comprising a pressure sensor
disposed in the bull nose.
6. The guide tool of claim 1, further comprising a vibration sensor
disposed in the bull nose.
7. The guide tool of claim 1, further comprising a temperature
sensor disposed in the bull nose.
8. The guide tool of claim 1, further comprising a fiber splice
coupled to the bull nose for making fiber connections.
9. The guide tool of claim 1, wherein the bull nose has a capsule
shape when in a neutral position.
10. An apparatus for use in a wellbore penetrating subsurface
formations, the apparatus comprising: a downhole tool; and
11. a guide tool having a bull nose, said bull nose having a first
section with an end that seals against and engages a lower end of
the downhole tool and a second section coupled to the first section
such that an axis of the second section is deflectable relative to
an axis of the first section.
12. The apparatus of claim 10, wherein the downhole tool comprises
a spoolable rod.
13. The apparatus of claim 10, wherein the downhole tool comprises
one or more wellbore tubulars.
14. The apparatus of claim 10, wherein the second section is
coupled to the first section by an indexing system that provides
indexed deflection.
15. The apparatus of claim 13, wherein the indexing system is
mechanically-activatable.
16. The apparatus of claim 14, wherein the indexing system is
activatable from a remote location by adjusting axial load on the
downhole tool.
17. The apparatus of claim 13, wherein the indexing system is
pressure-activated.
18. The apparatus of claim 16, wherein the indexing system is
activatable from a remote location by adjusting pressure in the
downhole tool.
19. The apparatus of claim 10, further comprising a pressure sensor
disposed in the bull nose.
20. The apparatus of claim 10, further comprising a vibration
sensor disposed in the bull nose.
21. The apparatus of claim 10, further comprising a temperature
sensor disposed in the bull nose.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Priority is claimed from U.S. Provisional Application No.
61/012,479, filed on Dec. 10, 2007.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The invention relates generally to well interventions. More
specifically, the invention relates to apparatus and method for
guiding a downhole tool through a wellbore having wellbore
restrictions.
[0005] 2. Background Art
[0006] In the extraction of oil and gas from underground
reservoirs, it is frequently necessary to insert a downhole tool or
an assembly of such tools, e.g., a tool "string", into a wellbore
drilled through the reservoir. It can be difficult to push tool
strings, examples of which include well completion strings,
workover strings, and logging tool systems to the full depth of the
wellbore due to restrictions in the wellbore. Examples of such
restrictions include ledges and washouts created during the
drilling of the wellbore, during well stimulation, during injection
of fluids into the reservoir from the Earth's surface, or while
producing fluids from the underground reservoir to the surface.
Ledges and washouts may also be created as a result of collapse of
the formation in which the wellbore is drilled, where the flow of
fluids from within the wellbore is insufficient to move debris from
the collapsed formation to the Earth's surface.
[0007] When inserting a relatively stiff ("stiff" being defined in
terms of bending moment) tool string, e.g., a tubular string or a
stiff well logging tool string, into a wellbore, the lower end of
the stiff tool string can be prevented from going further into the
wellbore if it lands against a washout or ledge formed as explained
above. A semi-stiff, spoolable rod, such as described in
International Application Publication No. WO 2006/003477, and used
to provide services under the service mark ZIPLOG, which is service
mark of the assignee of the present invention, may face the same
challenge as the stiff tool string when traversing a wellbore with
such restrictions. Another challenge related to such spoolable rods
is that the well equipment operator cannot visually or otherwise
determine if the lower end of the rod is moving or not. Failure to
determine such movement while the surface end of the rod is being
inserted into the wellbore can cause the equipment operator to
continue pushing the rod into the wellbore against a stopped lower
end of the rod, causing damage to or failure of the rod.
SUMMARY
[0008] In one aspect, a guide tool for mounting onto a downhole
tool for use in a wellbore penetrating subsurface formations is
provided. The guide tool has a bull nose. The bull nose has a first
section with an end for sealing against and engaging a lower end of
the downhole tool and a second section axially deflectably coupled
to the first section.
[0009] In another aspect, an apparatus for use in a wellbore
penetrating subsurface formations is provided. The apparatus
comprises a downhole tool and a guide tool having a bull nose. The
bull nose has a first section with an end that seals against and
engages a lower end of the downhole tool and a second section
axially deflectably coupled to the first section.
[0010] Other features and advantages of the invention will be
apparent from the following description and the appended
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The accompanying drawings, described below, illustrate
typical examples of the invention and are not to be considered
limiting of the scope of the invention, for the invention may admit
to other equally effective examples. The figures are not
necessarily to scale, and certain features and certain views of the
figures may be shown exaggerated in scale or in schematic in the
interest of clarity and conciseness.
[0012] FIG. 1 shows a wellbore penetrating subsurface formations
and an apparatus according to the present invention suspended in
the wellbore.
[0013] FIG. 2 is a diagram of a portion of the apparatus of FIG. 1
illustrating a guide tool attached to a lower end of a downhole
tool.
[0014] FIG. 3 shows the downhole tool and guide tool in an open
hole section of a wellbore in a stopped position.
[0015] FIG. 4 shows the hole finder of the guide tool oriented
outwardly in order to allow the downhole tool to continue along the
wellbore.
[0016] FIG. 5 shows the downhole tool hung up in a restriction in
the wellbore.
[0017] FIG. 6 shows the hole finder back in the neutral position,
which allows the downhole tool to continue along the wellbore.
DETAILED DESCRIPTION
[0018] The invention will now be described in detail with reference
to a few examples, as illustrated in the accompanying drawings. In
describing the examples, numerous specific details may be set forth
in order to provide a thorough understanding of the invention.
However, it will be apparent to those skilled in the art that the
invention may be practiced without some or all of these specific
details. In other instances, well-known features and/or processes
may not be described in detail so as not to unnecessarily obscure
the invention and because they would be within the ambit of one of
skill in the art. In addition, like or identical reference numerals
may be used to identify common or similar elements.
[0019] FIG. 1 shows a wellbore 100 drilled through subsurface
formations 102, 104. Subsurface formation 104 may be a hydrocarbon
producing formation. The wellbore 100 typically starts with a
vertical portion 106, which can extend anywhere from hundreds to
thousands of meters, and gradually or otherwise curves, for
example, into a horizontal portion 108, which can extend for
lengths up to several thousand meters. This particular wellbore
configuration is meant to serve as an example of possible
configurations of a wellbore that may be used with the invention
and is not intended to limit the scope of the invention. A pipe or
casing 110 extends from the surface 112 to a selected depth in the
wellbore 100 and is cemented in place in the wellbore 100. A
wellhead 114 is positioned at the surface 116, above the wellbore
100. The wellhead 114 includes various valves to regulate flow of
fluids from within the wellbore 100, as will be familiar to those
skilled in the art. The wellhead 114 also enables access into the
wellbore 100 for drilling and well intervention, for example.
[0020] In the example illustrated in FIG. 1, a wellbore apparatus,
generally identified at 118, extends from the wellhead 114 into the
wellbore 100. The wellbore apparatus 118 includes a downhole tool
120. In some examples, the downhole tool 120 may be a semi-stiff
tool, such as a semi-stiff, spoolable rod, as described in, for
example, International Publication No. WO 2006/003477, and as
stated in the Background section herein is used to provide services
under the service mark ZIPLOG by the assignee of the present
invention. As described in the '477 publication, the spoolable rod
includes one or more optical fibers encased in a thin metal barrier
layer, which in turn is encased in a composite layer. The downhole
tool 120 may be coupled to a surface system 122, which may include,
for example, a recording unit, a communications unit, and/or a
measurement unit (none of which is shown separately). In other
examples, the downhole tool 120 may be a stiff tool string made of
wellbore tubulars such as production tubing or drill pipe. The
downhole tool 120 may be used for work or intervention in the
wellbore 110. According to the present invention, the wellbore
apparatus 118 includes a guide tool 124 attached to the lower end
of the downhole tool 120. As will be explained below, the guide
tool 124 guides the lower end of the downhole tool 120 through
unexpected restrictions in the wellbore 100.
[0021] FIG. 2 is a simplified diagram showing the guide tool 124
and the features that enable the guide tool 124 to guide the
downhole tool 120 through unexpected restrictions in a wellbore. In
the diagram shown in FIG. 2, the guide tool 124 includes a bull
nose 126 having an upper end 128 that is attached to the downhole
tool 120 and a lower end 130 that is free. The shape of the lower
end 130 is generally rounded and configured to guide the bull nose
126 through the wellbore and away from restrictions in the
wellbore, such as, for example, liner hanger top, ledges, and/or
washouts. The shape of the upper end 128 may be similar to that of
the lower end 130 and may serve the same purpose as described above
when the downhole tool 120 is being pulled out of the wellbore. The
bull nose 126 with the rounded upper end 128 and lower end 130 has
a capsule shape in a neutral position. The upper end 128 of the
bull nose 126 may be attached to the downhole tool 120 via any
suitable mechanical gripping arrangement, indicated generally at
135. In some examples, the mechanical gripping arrangement 135 may
be similar to what is used to seal hydraulic tubing in a wellbore,
as will be familiar to those skilled in the art. In some examples,
the upper end 128 of the bull nose 126 sealingly engages the lower
end 125 of the downhole tool 120, thereby providing a pressure seal
barrier that prevents wellbore fluids from entering into an area
between the bull nose 126 and downhole tool 120 and the interior of
the downhole tool 120. The upper end 128 may sealingly engage the
lower end 125 of the downhole tool 120 via the mechanical gripping
arrangement 135.
[0022] The guide tool 124 may include one or more sensors, shown
generally at 132. In some examples, sensor 132a may be a vibration
sensor for measuring vibration of the downhole tool 120. Vibration
data from the vibration sensor 132a may be sent to the surface and
can be interpreted to determine if the downhole tool 120 is moving
in the wellbore or not, or to determine the depth of the downhole
tool 120 in the wellbore. If the readout of the vibration sensor
132a at the surface indicates no vibration, the operator may
conclude that the lower end of the downhole tool 120 is not moving
and may stop insertion or retraction of the downhole tool 120 into
or from the wellbore before physical damage to the downhole tool
120 or wellbore takes place. In other examples, sensor 132b may be
a temperature sensor for measuring differential temperature in the
wellbore. Such differential temperature may be correlated to the
depth of the downhole tool 120 in the wellbore. In other examples,
sensor 132c may be a pressure sensor for sensing pressure external
to the guide tool 124 or downhole tool 120.
[0023] Sensor(s) 132 as described above may be fiber-optic or
electrical. In some examples, the guide tool 124 may include a
fiber splice, shown generally at 133, for making connections
between an optical fiber(s) in the guide tool 124 and an optical
fiber(s) in the downhole tool 120. In other examples, the guide
tool 124 may include an electrical connector (not shown separately)
for making electrical connections between electrical components in
the guide tool 124 and electrical components in the downhole tool
120, e.g., where the sensor(s) 132 are electrical. The seal
provided at the upper end 128 of the bull nose 126, as explained
above, may function to prevent unwanted fluid from entering into an
area where the fiber optic and/or electrical connections are
made.
[0024] The bull nose 126 has an upper section 134 including the
upper end 128 and a lower section 136 including the lower end 130.
The lower section 136 may be coupled to the upper section 134 via
an indexing system, identified generally at 138. The indexing
system 138 provides indexed movement or deflection of the
longitudinal axis of the lower section 136 with respect to the
longitudinal axis of the upper section 134. The indexing system 138
can deflect the lower section 136 relative to the upper section 134
through a set of preset angles, e.g., 0.degree., 45.degree.,
90.degree., 120.degree., without decoupling the lower section 136
from the upper section 134. Deflection is enabled by rotation about
the connection area, generally indicated at 139, between the upper
section 134 and the lower section 136. The indexing system 138 may
be, for example, mechanically-activated, pressure-activated, or
electrically-activated. In some examples, a mechanically-activated
indexing system 138 may be a spring-loaded indexing system that can
be activated by adjustment of applied axial load. Such indexing may
take the form of a set of J-slots (not shown) such as shown in U.S.
Pat. No. 5,433,276 issued to Martain et al. The lower section 136
functions as a "hole finder" that will ensure that the bull nose
126 is oriented toward the continued wellbore in case the bull nose
126 is lodged against a restriction in the wellbore. A restriction
in the wellbore is essentially any structure or feature that can
stop the downhole tool 120 from progressing along the wellbore.
[0025] FIG. 3 shows the guide tool 124 and attached downhole tool
120 in an open hole section 142 of the wellbore 100. This example
of the open hole section 142 includes a featured called a "washout"
144. In the example of FIG. 3, the downhole tool 120 is stopped
from moving along the wellbore 100 by the washout 144. The well
equipment operator at the surface may detect that the downhole tool
120 is no longer moving, for example, by receiving vibration data
from the guide tool 124 and interpreting the vibration data. When
it is determined that the downhole tool 120 is no longer moving,
the operator can take actions to activate the hole finder 136. The
hole finder 136 in the present example can be activated by
controlling axial load on the downhole tool 120 from the surface.
In some examples, the operator can cause the downhole tool 120 to
move upwardly by removing axial load from the downhole tool 120.
Removing axial load from the downhole tool 120 can cause the
indexing system (138 in FIG. 2) to orient the hole finder 136 to an
outward angle with respect to the longitudinal axis of the downhole
tool 120, as shown in FIG. 4. In other examples, the operator can
increase fluid pressure in the interior of the downhole tool 120 to
cause the indexing system 138 to orient the hole finder 136 to an
outward angle as described above. With the hole finder 136 oriented
outwardly, the operator can move the downhole tool 120 downwardly
(i.e., along the wellbore) once again, whereby the hole finder 136
overcomes the washout 144.
[0026] Referring to FIG. 5, orientation of the hole finder 136
after the activation described above may be such that the guide
tool 124 becomes lodged in a later restriction 146 (such as a
reduced-diameter section) in the wellbore 100, thereby preventing
the downhole tool 120 from advancing along the wellbore 100. Again,
the operator may determine that the downhole tool 120 is no longer
moving by, for example, interpreting vibration data sent to the
surface from sensors in the guide tool 124. In some examples, the
operator may release the guide tool 124 by moving the downhole tool
120 upwardly as described above, wherein removal of axial load from
the downhole tool 120 causes the hole finder 136 to move to the
previous angle, which in FIG. 6 is the centered or neutral position
where the hole finder 136 is aligned axially with the downhole tool
120. In other examples, the operator may cause the hole finder 136
to return to the previous angle (or centered/neutral position) by
releasing pressure from the interior of the downhole tool 120. Once
the hole finder 136 is reoriented, the operator can move the
downhole tool 120 along the wellbore once again. If the downhole
tool 120 hangs up once again in the wellbore 100, the hole finder
136 can be activated as described above to orient the hole finder
136 to a next outward angle, e.g., 450 from the previous angle.
Activation of the hole finder 136 can be repeated as necessary to
engage one or more of a number of different angle settings, for
example, 0.degree., 45.degree., 90.degree., and 135.degree. (where
0.degree. may represent the neutral/centered position).
[0027] A guide tool according to the various aspects of the
invention may provide a wellbore equipment operator to avoid tool
damage, and to continue operations in a wellbore having
obstructions with minimum delay.
[0028] While the invention has been described with respect to a
limited number of examples, those skilled in the art, having
benefit of this disclosure, will appreciate that other examples can
be devised which do not depart from the scope of the invention as
disclosed herein. Accordingly, the scope of the invention should be
limited only by the attached claims.
* * * * *