U.S. patent application number 10/707235 was filed with the patent office on 2005-06-02 for improved downhole tool liner.
Invention is credited to Bradford, Kline, Briscoe, Michael, Dahlgren, Scott, Fox, Joe, Hall, David R., Pixton, David S..
Application Number | 20050115717 10/707235 |
Document ID | / |
Family ID | 34619821 |
Filed Date | 2005-06-02 |
United States Patent
Application |
20050115717 |
Kind Code |
A1 |
Hall, David R. ; et
al. |
June 2, 2005 |
Improved Downhole Tool Liner
Abstract
A liner insertable into the central bore of a downhole tool
includes a resilient material rolled into a substantially
cylindrical shape. The outside diameter of the liner is variable to
allow the liner to be inserted into a narrowed bore of the downhole
tool near the box end or pin end. Once past the narrowed bore, the
outside diameter of the liner self-expands within the central bore
of the downhole tool. The outside diameter of the liner may expand
to contact the inside surface of the central bore. In selected
embodiments, a transmission line may be routed between the central
bore and the outside diameter of the resilient material. The liner
may be effective to protect the transmission line from materials
traveling through the central bore.
Inventors: |
Hall, David R.; (Provo,
UT) ; Pixton, David S.; (Lehi, UT) ; Briscoe,
Michael; (Lehi, UT) ; Bradford, Kline; (Orem,
UT) ; Fox, Joe; (Spanish Fork, UT) ; Dahlgren,
Scott; (Provo, UT) |
Correspondence
Address: |
JEFFREY E. DALY
GRANT PRIDECO, L.P.
400 N. SAM HOUSTON PARKWAY EAST
SUITE 900
HOUSTON
TX
77060
US
|
Family ID: |
34619821 |
Appl. No.: |
10/707235 |
Filed: |
November 29, 2003 |
Current U.S.
Class: |
166/380 ;
166/242.1; 175/320 |
Current CPC
Class: |
E21B 17/1035 20130101;
E21B 17/003 20130101 |
Class at
Publication: |
166/380 ;
166/242.1; 175/320 |
International
Class: |
E21B 017/00 |
Goverment Interests
[0001] This invention was made with government support under
Contract No. DE-FC26-97FT343656 awarded by the U.S. Department of
Energy. The government has certain rights in the invention.
Claims
1. A liner insertable into the central bore of a downhole tool, the
central bore being characterized by a standard diameter along the
central portion of the tool, and a narrowed diameter proximate the
ends of the tool, the liner comprising: a resilient material rolled
into a substantially cylindrical shape and having an outside
diameter, wherein: the outside diameter of the resilient material
is variable to allow the resilient material to move through the
narrowed diameter of the downhole tool; and the outside diameter of
the resilient material, once past the narrowed diameter, is
expandable within the standard diameter of the downhole tool.
2. The liner of claim 1, wherein the outside diameter of the
resilient material expands to contact the inside surface of the
central bore.
3. The liner of claim 1, further comprising a transmission line
routed between the central bore and the outside diameter of the
resilient material.
4. The liner of claim 3, wherein the resilient material keeps the
transmission line in contact with the inside surface of the central
bore.
5. The liner of claim 3, wherein the resilient material is
effective to protect the transmission line from materials traveling
through the central bore.
6. The liner of claim 3, wherein a channel is formed in the
resilient material to accommodate the transmission line.
7. The liner of claim 6, wherein the resilient material comprises
two mating surfaces that mate to form the cylindrical shape.
8. The liner of claim 7, wherein movement between the mating
surfaces is effective to cause a change in diameter of the
resilient material.
9. The liner of claim 7, wherein the mating surfaces are sealed
together to prevent substances from leaking out of the liner.
10. The liner of claim 1, wherein the resilient material, once
expanded, is maintained in place by shoulders within the downhole
tool.
11. A method for lining the central bore of a downhole tool, the
central bore having a central portion of a standard diameter, and
tool ends of a narrower diameter, the method comprising: rolling a
resilient material into a substantially cylindrical shape;
inserting the resilient material into the central bore through at
least one tool end into the central portion of the downhole tool;
and expanding, by the resilient material, the outside diameter of
the resilient material within the central portion of the central
bore.
12. The method of claim 11, further comprising expanding, by the
resilient material, the outside diameter of the resilient material
to contact the inside surface of the central bore.
13. The method of claim 11, further comprising routing a
transmission line between the central bore and the outside diameter
of the resilient material.
14. The method of claim 13, further comprising maintaining, by the
resilient material, contact between the transmission line and the
inside surface of the central bore.
15. The method of claim 13, further comprising protecting, by the
resilient material, the transmission line from materials traveling
through the central bore.
16. The method of claim 13, further comprising forming a channel in
the resilient material to accommodate the transmission line.
17. The method of claim 11, wherein the resilient material
comprises two mating surfaces that mate to form the cylindrical
shape.
18. The method of claim 17, further comprising moving the mating
surfaces with respect to one another to change the diameter of the
resilient material.
19. The method of claim 17, further comprising sealing the mating
surfaces to one another to prevent substances from leaking out of
the liner.
20. A method for lining the central bore of a downhole tool, the
method comprising: providing a resilient liner formed into a
substantially cylindrical shape, the resilient liner having an
outside diameter sized to fit within the central bore; inserting
the resilient liner into the central bore; and expanding, by the
resilient material, the outside diameter of the resilient material
within the central bore.
Description
BACKGROUND OF INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to oil and gas drilling, and more
particularly to apparatus and methods for reliably transmitting
information along downhole drilling strings.
[0004] 2. Background of the Invention
[0005] In the downhole drilling industry, MWD and LWD tools are
used to take measurements and gather information with respect to
downhole geological formations, status of downhole tools,
conditions located downhole, and the like. Such data is useful to
drill operators, geologists, engineers, and other personnel located
at the surface. This data may be used to adjust drilling
parameters, such as drilling direction, penetration speed, and the
like, to accurately tap into an oil, gas, or other mineral bearing
reservoirs. Data may be gathered at various points along the drill
string. For example, sensors, tools, and the like may be located at
or near the bottom hole assembly and on intermediate tools located
at desired points along the drill string.
[0006] Nevertheless, data gathering and analysis represent only
certain aspects of the overall process. Once gathered, apparatus
and methods are needed to rapidly and reliably transmit the data to
the earth's surface. Traditionally, technologies such as mud pulse
telemetry have been used to transmit data to the surface. However,
most traditional methods are limited to very slow data rates and
are inadequate for transmitting large quantities of data at high
speeds.
[0007] In order to overcome these limitations, various efforts have
been made to transmit data along electrical or other types of cable
integrated directly into drill string components, such as sections
of drill pipe. In such systems, electrical contacts or other
transmission elements are used to transmit data across tool joints
or connection points in the drill string. Nevertheless, many of
these efforts have been largely abandoned or frustrated due to
unreliability and complexity.
[0008] For example, one challenge is effectively integrating a
transmission line into a downhole tool, such as a section of drill
pipe. Due to the inherent nature of drilling, most downhole tools
have a similar cylindrical shape defining a central bore. The wall
thickness surrounding the central bore is typically designed in
accordance with weight, strength, and other constraints imposed by
the downhole environment. In some cases, milling or forming a
channel in the wall of the downhole tool to accommodate the
transmission line may excessively weaken the wall. Thus, in certain
embodiments, the only practical route for the transmission line is
through the central bore of a downhole tool.
[0009] Nevertheless, routing the transmission line through the
central bore may expose the transmission line to drilling fluids,
cements, wireline tools, or other substances or objects passing
through the central bore. This can damage the transmission line or
cause the transmission line to interfere with objects or substances
passing through the central bore. Moreover, in directional drilling
applications, downhole tools may bend slightly as a drill string
deviates from a straight path. This may cause the transmission line
to deviate away from the inside surface of the central bore,
thereby worsening the obstruction within the central bore.
[0010] Thus, what are needed are apparatus and methods to protect a
transmission line, routed through the central bore of a downhole
tool, from drilling fluids, cement, wireline tools, or other
components traveling through the central bore.
[0011] What are further needed are apparatus and methods to
maintain a transmission line against the inside surface of the
central bore even when the downhole tool bends or deviates from a
linear path.
[0012] What are further needed are apparatus and methods for lining
the inside surface of the central bore to isolate a transmission
line from objects or substances traveling through the central
bore.
SUMMARY OF INVENTION
[0013] In view of the foregoing, it is a primary object of the
present invention to provide apparatus and methods for protecting a
transmission line, routed through the central bore of a downhole
tool, from drilling fluids, cement, wireline tools, or other
components traveling through the central bore. If is a further
object to maintain a transmission line against the inside surface
of the central bore even when the downhole tool bends or deviates
from a straight path. It is yet a further object to provide
apparatus and methods for lining the inside surface of the central
bore to isolate a transmission line from objects or substances
traveling through the central bore.
[0014] Consistent with the foregoing objects, and in accordance
with the invention as embodied and broadly described herein, a
liner insertable into the central bore of a downhole tool, wherein
the central bore has a standard diameter along a central portion of
the tool, and a narrower diameter near the ends of the downhole
tool, is disclosed in one embodiment of the invention as including
a resilient material rolled into a substantially cylindrical shape.
The outside diameter of the resilient material is variable to allow
the resilient material to move through the narrower diameter of the
central bore. Once past the narrower diameter of the central bore,
the outside diameter of the resilient material self-expands within
the standard diameter of the downhole tool.
[0015] In selected embodiments, the outside diameter of the
resilient material expands to contact the inside surface of the
central bore. In other embodiments, a transmission line is routed
between the central bore and the outside diameter of the resilient
material. The resilient material may keep the transmission line in
contact with the inside surface of the central bore. The resilient
material may also be effective to protect the transmission line
from materials traveling through the central bore.
[0016] In certain embodiments, a channel is formed in the resilient
material to accommodate the transmission line. In other
embodiments, the resilient material includes two mating surfaces
that come together to form the cylindrical shape. Movement between
these mating surfaces is effective to cause a change in diameter of
the resilient material. In selected embodiments, the mating
surfaces are sealed together to prevent substances from leaking
into or out of the liner. In certain embodiments, once the
resilient material has expanded within the central portion of the
downhole tool, the resilient material is maintained in place by
shoulders in the central bore.
[0017] In another aspect of the invention, a method for lining the
central bore of a downhole tool, wherein the central bore has a
central portion of a standard diameter, and tool ends of a narrower
diameter, includes rolling a resilient material into a
substantially cylindrical shape. The resilient material is then
inserted into the central bore through the one of the tool ends
into the central portion of the central bore. Once in place, the
diameter of the resilient material self-expands within the central
portion of the central bore.
[0018] In selected embodiments, the method includes expanding, by
the resilient material, the outside diameter of the resilient
material to contact the inside surface of the central bore. In
other embodiments, the method includes routing a transmission line
between the central bore and the outside diameter of the resilient
material. The resilient material may maintain contact between the
transmission line and the inside surface of the central bore. The
resilient material may also protect the transmission line from
materials traveling through the central bore.
[0019] In selected embodiments, the method may include forming a
channel in the resilient material to accommodate the transmission
line. In other embodiments, the resilient material includes two
mating surfaces that mate together to form the cylindrical shape.
The diameter of the resilient material may be varied by moving the
mating surfaces with respect to one another. In selected
embodiments, the method may further include sealing the mating
surfaces to one another to prevent substances from leaking into or
out of the liner.
[0020] In another aspect of the invention, a method for lining the
central bore of a downhole tool includes providing a resilient
liner having a substantially cylindrical shape and an outside
diameter sized to fit within the central bore. The method further
includes inserting the resilient liner into the central bore and
expanding, by the resilient material, the outside diameter of the
resilient material within the central bore.
BRIEF DESCRIPTION OF DRAWINGS
[0021] The foregoing and other features of the present invention
will become more fully apparent from the following description,
taken in conjunction with the accompanying drawings. Understanding
that these drawings depict only typical embodiments in accordance
with the invention and are, therefore, not to be considered
limiting of its scope, the invention will be described with
additional specificity and detail through use of the accompanying
drawings.
[0022] FIG. 1 is a cross-sectional view illustrating one embodiment
of a drill rig in accordance with the invention.
[0023] FIG. 2 is a cross-sectional view illustrating one embodiment
of a transmission line integrated into a downhole tool.
[0024] FIG. 3 is a cross-sectional view illustrating one embodiment
of a transmission line routed through the central bore of a
downhole tool when the downhole tool is curved or bent as is
customary in directional drilling applications.
[0025] FIG. 4 is a perspective view illustrating one embodiment of
a downhole tool liner in accordance with the invention.
[0026] FIG. 5 is a perspective view illustrating one embodiment of
a downhole tool liner in accordance with the invention as it is
initially inserted into the central bore of a downhole tool.
[0027] FIG. 6 is a cross-sectional view illustrating one embodiment
of a downhole tool liner as it is initially inserted into the
central bore of a downhole tool.
[0028] FIG. 7 is a cross-sectional view illustrating one embodiment
of a downhole tool liner after it expands into the larger diameter
of the central bore.
[0029] FIG. 8 is a cross-sectional view illustrating one embodiment
of a downhole tool liner within the central bore of a downhole
tool, wherein the liner is used to isolate a transmission line from
objects or substances passing through the central bore.
[0030] FIG. 9 is a cross-sectional view illustrating one embodiment
of a downhole tool liner inserted into the central bore of a
downhole tool, wherein the liner includes a channel to accommodate
a transmission line.
DETAILED DESCRIPTION
[0031] It will be readily understood that the components of the
present invention, as generally described and illustrated in the
Figures herein, could be arranged and designed in a wide variety of
different configurations. Thus, the following more detailed
description of embodiments of apparatus and methods of the present
invention, as represented in the Figures, is not intended to limit
the scope of the invention, as claimed, but is merely
representative of various selected embodiments of the
invention.
[0032] The illustrated embodiments of the invention will be best
understood by reference to the drawings, wherein like parts are
designated by like numerals throughout. Those of ordinary skill in
the art will, of course, appreciate that various modifications to
the apparatus and methods described herein may easily be made
without departing from the essential characteristics of the
invention, as described in connection with the Figures. Thus, the
following description of the Figures is intended only by way of
example, and simply illustrates certain selected embodiments
consistent with the invention as claimed herein.
[0033] Referring to FIG. 1, a cross-sectional view of a drill rig
10 is illustrated drilling a borehole 14 into the earth 16 using
downhole tools (collectively indicated by numeral 12) in accordance
with the present invention. The collection of downhole tools 12
form at least a portion of a drill string 18. In operation, a
drilling fluid is typically supplied under pressure at the drill
rig 10 through the drill string 18. The drill string 18 is
typically rotated by the drill rig 10 to turn a drill bit 12e which
is loaded against the earth 16 to form the borehole 14.
[0034] Pressurized drilling fluid is circulated through the drill
bit 12e to provide a flushing action to carry the drilled earth
cuttings to the surface. Rotation of the drill bit may alternately
be provided by other downhole tools such as drill motors, or drill
turbines (not shown) located adjacent to the drill bit 12e. Other
downhole tools include drill pipe 12a and downhole instrumentation
such as logging while drilling tools 12c, and sensor packages, (not
shown). Other useful downhole tools include stabilizers 12d, hole
openers, drill collars, heavyweight drill pipe, subassemblies,
under-reamers, rotary steerable systems, drilling jars, and
drilling shock absorbers, which are all well known in the drilling
industry.
[0035] Referring to FIG. 2, a downhole tool 12 may include a box
end 36 and a pin end 36. A pin end 38 may thread into a box end 36,
thereby connecting multiple tools 12 together to form a drill
string 18. Due to the inherent nature of drilling, most downhole
tools 12 are characterized by a similar cylindrical shape defining
a central bore 35. The central bore is used to transport drilling
fluids, wireline tools, cement, and the like down the drill string
18.
[0036] The wall thickness 39 around the central bore 35 is
typically designed in accordance with weight, strength, and other
constraints, needed to withstand substantial torque placed on the
tool 12, pressure within the central bore 35, flex in the tool 12,
and the like. Because of immense forces placed on the tool 12,
milling or forming a channel in the wall of the downhole tool 12 to
accommodate a transmission line 34 may excessively weaken the wall.
Thus, in selected embodiments, the only practical route for a
transmission line 34 is through the central bore 35 of the downhole
tool 12.
[0037] Nevertheless, routing the transmission line 34 through the
central bore may expose the transmission line 34 to drilling
fluids, cements, wireline tools, or other substances or objects
passing through the central bore 35. This can damage the
transmission line 34 or cause the transmission line 34 to
negatively interfere with objects or substances passing through the
central bore 35. Thus, in selected embodiments, a transmission line
34 is preferably maintained as close to the wall 39 of the central
bore 39 as possible to minimize interference. In selected
embodiments, the transmission line 34 is protected by a conduit 34
or other protective covering 34 to protect it from damage.
[0038] As illustrated, at or near the box end 36 and pin end 38 of
the tool 12, the central bore 35 may be narrower and the walls 41
may be thicker. This may increase the strength of the downhole tool
12 at or near the tool joints. In addition, this added thickness 41
may enable channels to be milled or formed in the walls 42, 44, to
accommodate a transmission line 34 without overly weakening the
downhole tool 12. The channels 42, 44 may exit the downhole tool at
or near the ends of the downhole tool 12, where the transmission
line 34 may be coupled to transmission elements (not shown) for
communicating across tool joints.
[0039] Referring to FIG. 3, In an effort to tap into gas, oil, or
other mineral deposits, a drill string 18 may be guided or deviate
from a linear path. Thus, in selected directional drilling
applications, tools 12 may bend to veer off in a desired direction
at an angle 32. Since a drill string 18 may consist of many
hundreds of sections of drill pipe 12 and other downhole tools 12,
the cumulative bend or curve in each tool 12 may enable a drill
string 18 to drill horizontally in some cases.
[0040] As was previously mentioned, in order to transmit data up
and down the drill string 18, a transmission line 34 may be
integrated into a downhole tool 12. If the transmission line 34 is
routed through the central bore 35 of the downhole tool 12, the
transmission line 34 may separate or detach from the inside surface
of the central bore 35 when the downhole tool 12 bends. This may
create problems since the transmission line 34 may then obstruct or
interfere with fluids, wireline tools, concrete, or other objects
or substances traveling through the central bore. In fact, in some
cases, when a downhole tool 12, such as a section of drill pipe 12,
bends significantly, the transmission line 34 may actually come
into contact with the opposite side 37 of the central bore 35.
Thus, apparatus and methods are needed to route a transmission line
34 through the central bore 35 such that the transmission line 34
stays in relatively constant contact with the inside surface of the
central bore 35 even when the downhole tool 12 bends.
[0041] Referring to FIG. 4, in selected embodiments, a liner 46 may
be provided to line the inside surface of the central bore 35. The
liner 46 may be used to protect or isolate the transmission line 34
from substances or objects passing through the central bore 35. As
illustrated, a liner 46 may be formed from a rolled material and
have a substantially cylindrical shape.
[0042] In selected embodiments, the liner 46 may include mating
surfaces 50, 52 that contact one another to form the cylinder. The
mating surfaces 50, 52 may move with respect to one another to roll
the liner 46 more tightly to provide a smaller diameter 54. Thus,
the diameter 54 of the liner may be adjusted as needed. This may be
helpful to initially insert the liner 46 into the central bore 35
of a downhole tool 12. The liner may be constructed of any suitable
resilient material capable of withstanding the wear of a downhole
environment. For example, a liner 46 may be constructed of a
material such as metal, plastic, or the like, having sufficient
durability and resiliency.
[0043] Referring to FIG. 5, a liner 46 like that described in
Figure 4 may be inserted into either the box end 36 or pin end 38
of a downhole tool 12. As illustrated, a pin end 38 may include a
primary 60 and secondary shoulder 58, and a threaded portion 55,
which may contact another downhole tool 12. The primary shoulder 60
may absorb the majority of the stress at the tool joint.
Nevertheless the secondary shoulder 58 may also absorb some of the
stress at the tool joint. The two shoulders 58, 60 together may
create a stronger tool joint than either shoulder by itself.
[0044] As illustrated, a transmission element 56 may be installed
into the secondary shoulder 58. The transmission element 56 may be
used to transmit a signal across the tool joint by communicating
with a corresponding transmission element 56 located on another
downhole tool 12 (not shown). The transmission element 56 may
transmit energy in several different ways. For example, in selected
embodiments, the transmission element 58 may transmit electrical
energy by direct electrical contact another transmission element
58.
[0045] In other embodiments, the transmission element 58 may
communicate inductively. That is, the transmission element 58 may
convert an electrical signal to magnetic energy for transmission
across the tool joint. The magnetic energy may then be converted
back to an electrical signal by another transmission element 58. To
accommodate the transmission element 58, a recess may be formed in
the secondary shoulder 58. The transmission line 34 may connect to
the transmission element 58 through the channel 44 in the pin end
38.
[0046] As was previously mentioned, the central bore 35 traveling
through the pin end 38 may be narrower than the central bore 35
traveling through the central portion of the tool 12. Thus, in
order to insert the liner 46 into the downhole tool 12, the
diameter 54 of the liner 46 may be reduced. This may be
accomplished by rolling the liner 46 into a smaller cylinder. The
liner 46 may then be inserted in a direction 62 into the downhole
tool 12. In selected embodiments, the liner 46 may be lubricated to
facilitate sliding the liner 46 into the tool 12.
[0047] Referring to FIG. 6, a cross-sectional view of a liner 46 is
illustrated as it is inserted into a downhole tool 12. As shown,
the liner 46 may be inserted with an initial diameter 54 so it can
slide through the narrow bore 64 in either the box end 36 or pin
end 38. The liner 46 may be cut to a specified length 66 to fit
within a central portion 66 of the downhole tool 12.
[0048] Referring to FIG. 7, once the liner 46 reaches the central
portion 66 of the central bore 35, the diameter 54 of the liner 46
may increase to contact the inside surface of the central bore 35.
As was previously described, the liner 46 may self-expand within
the central bore 35 due to its resiliency. For example, if the
liner 46 is a sheet of a resilient material rolled into a
cylindrical shape, the diameter 54 of the liner 46 may
automatically expand due to its resiliency.
[0049] Once the diameter 54 of the liner 46 has expanded to contact
the inside surface of the central bore 35, the liner 46 may kept in
place 12 by shoulders 68a, 68b near the box and pin ends 36, 38.
The shoulders 68a, 68b may be present where the central bore 15
narrows near the box end 36 and pin end 38. Likewise, the
resiliency of the liner 46 may keep the liner 46 from slipping past
the shoulders 68a, 68b. In selected embodiments, the more resilient
the material 46, the better the retention between the shoulders
68a, 68b.
[0050] It is important to securely retain the liner 46 between the
shoulders 68a, 68b. For example, if the liner 46 slips past the
shoulders 68a, 68b, the liner 46 may create an obstruction within
the central bore 15. This may cause the drill string to
malfunction, possibly causing time-consuming and costly delays. In
other embodiments, the liner 46 may be welded or otherwise bonded
to the inside of the downhole tool 12 to keep it from moving.
[0051] Referring to FIG. 8, a cross-sectional view of the central
portion 66 of a downhole tool 12 is illustrated. As shown, the
transmission line 34 may be sandwiched between the liner 46 and the
surface of the central bore 35. This may protect the transmission
line 34 from objects or substances passing through the central bore
35. In selected embodiments, the mating surfaces 50, 52 may be
sealed together to prevent fluids or other substances from leaking
from the liner 46. In other embodiments, the mating surfaces 50, 52
may be left unsealed.
[0052] Referring to FIG. 9, in other embodiments, a channel 70 may
be formed in the liner 46 to accommodate the transmission line 34.
The channel 70 may maintain the transmission line 34 in place and
provide better contact between the liner 46 and inside surface of
the central bore 35.
[0053] The present invention may be embodied in other specific
forms without departing from its essence or essential
characteristics. The described embodiments are to be considered in
all respects only as illustrative, and not restrictive. The scope
of the invention is, therefore, indicated by the appended claims,
rather than by the foregoing description. All changes within the
meaning and range of equivalency of the claims are to be embraced
within their scope.
* * * * *