U.S. patent application number 13/847823 was filed with the patent office on 2013-09-26 for downhole tool roller device with cylindrical bearing mechanism.
This patent application is currently assigned to Schlumberger Technology Corporation. The applicant listed for this patent is SCHLUMBERGER TECHNOLOGY CORPORATION. Invention is credited to Derek Copold, Serko Sarian, Sashank Vasireddy.
Application Number | 20130248208 13/847823 |
Document ID | / |
Family ID | 49210715 |
Filed Date | 2013-09-26 |
United States Patent
Application |
20130248208 |
Kind Code |
A1 |
Copold; Derek ; et
al. |
September 26, 2013 |
Downhole Tool Roller Device With Cylindrical Bearing Mechanism
Abstract
Roller devices for passively or actively aiding in the
conveyance of a toolstring through a well. The well may be of
tortuous architecture and include a host of different corrosives.
However, the roller devices are equipped with a cylindrical bearing
based mechanism such as a journal bearing. Thus, these devices may
be substantially less prone to exposure to corrosives. For example,
they may be provided in a substantially monolithic circumferential
form more readily shielded and/or isolated from such direct
exposure.
Inventors: |
Copold; Derek; (Sugar Land,
TX) ; Vasireddy; Sashank; (Stafford, TX) ;
Sarian; Serko; (Houston, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SCHLUMBERGER TECHNOLOGY CORPORATION |
Sugar Land |
TX |
US |
|
|
Assignee: |
Schlumberger Technology
Corporation
Sugar Land
TX
|
Family ID: |
49210715 |
Appl. No.: |
13/847823 |
Filed: |
March 20, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61613261 |
Mar 20, 2012 |
|
|
|
Current U.S.
Class: |
166/385 ;
166/241.1; 166/381; 166/50 |
Current CPC
Class: |
E21B 17/1057
20130101 |
Class at
Publication: |
166/385 ;
166/241.1; 166/50; 166/381 |
International
Class: |
E21B 17/10 20060101
E21B017/10 |
Claims
1. A roller device for incorporation into a housing of a downhole
toolstring to aid conveyance thereof through a well, the device
comprising: a body with an exposed surface for contacting a wall of
the well during the conveyance through the well; and a cylindrical
bearing based mechanism for disposal at an underside of said body
opposite the exposed surface.
2. The roller device of claim 1 wherein said cylindrical bearing
based mechanism comprises a journal bearing.
3. The roller device of claim 2 wherein said journal bearing is
substantially circumferentially monolithic.
4. The roller device of claim 2 wherein said journal bearing
comprises: a first journal piece; and a second journal piece
adjacent said first with an isolated slip interface
therebetween.
5. The roller device of claim 1 wherein said cylindrical bearing
based mechanism comprises a cylindrical roller bearing for radial
and axial slip.
6. A downhole tool for incorporation into a toolstring and for
conveyance through a well, the tool comprising: a housing; and a
roller device accommodated by said housing for contacting a wall of
the well during the conveyance therethrough, the device comprising
a cylindrical bearing based mechanism to allow rolling thereof
during the contacting of the wall.
7. The tool of claim 6 wherein said roller device is of a diameter
larger than the toolstring.
8. The tool of claim 6 wherein the toolstring is between about 50
feet and 150 feet in length.
9. The tool of claim 8 wherein the well includes a bend to a
non-vertical section.
10. The tool of claim 6 wherein said roller device is one of
exteriorly disposed relative said housing, at least partially
recessed into said housing and extended from said housing.
11. The tool of claim 10 wherein the roller device is a first
roller device, the tool further comprising a second roller device
at an opposite side of said housing relative the first roller
device.
12. The tool of claim 11 further comprising a formation disturbing
implement at said housing between said roller devices, said roller
devices exteriorly disposed and to provide a foothold at a wall of
the well for substantially perpendicular orientation of said
implement relative the wall.
13. The tool of claim 12 wherein said formation disturbing
implement is a sampling implement for attaining substantially
sealed engagement with the wall during sampling due to the
perpendicular orientation.
14. The tool of claim 11 wherein the roller devices are dual-sided
and extended from said housing to promote a degree of
centralization of the tool in the well.
15. A method of conveying a toolstring through a well, the method
comprising: deploying the toolstring into the well over a well
access line; employing a roller device for assistance in aiding
conveyance of the toolstring to a target location in the well; and
utilizing a cylindrical bearing based mechanism of the roller
device during said employing thereof for conveyance assistance.
16. The method of claim 15 wherein deploying of the toolstring is a
coiled tubing deployment and the well access line is coiled
tubing.
17. The method of claim 15 further comprising performing an
application with a tool of the toolstring at the target
location.
18. The method of claim 17 wherein the application is a formation
sampling application.
19. The method of claim 18 further comprising substantially
perpendicularly orienting a formation sampling implement of the
tool relative a wall of the well for the application with the
roller device.
20. The method of claim 15 further comprising enhancing
centralization of the tool in the well with the roller device
during the conveyance through the well.
Description
PRIORITY CLAIM/CROSS REFERENCE TO RELATED APPLICATION(S)
[0001] This Patent Document claims priority under 35 U.S.C. .sctn.
119 to U.S. Provisional App. Ser. No. 61/613,261, entitled
"Conveyance Accessories" filed on Mar. 20, 2012, and incorporated
herein by reference in its entirety.
BACKGROUND
[0002] Exploring, drilling and completing hydrocarbon and other
wells are generally complicated, time consuming and ultimately very
expensive endeavors. In recognition of these expenses added
emphasis has been placed on maximizing each given well's life and
productivity over the course of the well's life. Thus, well
logging, profiling and monitoring of well conditions are playing an
ever increasing role in oilfield operations. Similarly, more
actively interventional applications are regularly called for such
as clean-out applications, opening or closing valves and sliding
sleeves or any number of other maneuvers targeting maximized
recovery and well life.
[0003] In addition to regular intervention for sake of monitoring
and/or managing well operations, the well itself may also be of
fairly sophisticated architecture. For example, in an attempt to
maximize recovery from the reservoir and extend the useful life of
the well, it may be of a fairly extensive depth and tortuous
configuration. This may include overall depths in the tens of
thousands of feet range. Once more, such wells may include extended
horizontal or deviated sections of several thousand feet. As a
result, interventions through such wells are becoming of ever
increasing difficulty as noted below.
[0004] Where interventional applications are sought in wells of
particularly challenging architecture, wireline cable, coiled
tubing, drill pipe or other semi-rigid conveyance line may be
utilized to deliver an interventional tool to a target location in
the well. In order to help the conveyance line navigate the well
downhole, conveyance aids are available to help the conveyance line
and toolstring traverse the challenging architecture of the well.
These may include active conveyance aids such as tractors or
vibration tools, generally located near the end of conveyance line
near the toolstring. Thus, the conveyance line may be actively
pulled further downhole or vibrated in such a manner as to help
extend the overall reach of the conveyance line.
[0005] In light of the potential drawbacks to conveyance aids noted
above, a toolstring may be outfitted with more straight-forward,
passive features to help in traversing a well of sophisticated
architecture. For example, the toolstirng or a housing of a given
tool may be equipped with passive rollers. That is, conventional,
appropriate sized wheel-like features may be placed at the outer
surface of the toolstring. So, for example, where a 100 foot
toolstring is rounding a transition bend of a few hundred feet or
so into a deviated well section, the rollers may passively contact
the well wall as the bend is rounded. This may prevent mechanical
or even differential sticking in such situations. Once more,
preventing such sticking in this manner may be the extent of the
conveyance aid that is required in order to allow the tool to reach
the target location downhole. That is, the challenge in delivering
the toolstring to the downhole target location at times may be less
about overall load capacity throughout the well, for example, as
may be met by a heavy duty tractor, and more about being able to
passively round a bend at a given location. Certainly where this is
the case, passive roller-aided conveyance may be preferable to
other aiding techniques.
[0006] Unfortunately, while passive roller-aided conveyance may be
suitable for helping the toolstring to reach a downhole target
location in theory, rollers face their own inherent limitations.
For example, passive, and even active rollers, generally include
bearing ring assemblies similar to those found in wheels on
conventional pair of roller skates. Setting aside manufacturability
disadvantages, these types of assemblies are also relatively
short-lived upon exposure to downhole environments. That is, it is
understandable that a host of spherical bearings exposed to debris,
sand or downhole fluids tends to lock-up and/or corrode fairly
quickly. Indeed, after every couple of deployments into the well,
it is likely that replacement of all of the bearing assemblies for
the toolstring is called for. Yet, in spite of these added
maintenance and materials costs, this is often the operators' most
practical option for aiding in the conveyance of the
toolstring.
SUMMARY
[0007] A downhole toolstring is provided that includes a tool
housing equipped with a conveyance aid. The conveyance aid includes
at least two roller devices for contacting a wall of the well
during the conveyance therethrough. Further, the roller devices
themselves each include a cylindrical bearing based mechanism to
allow rolling thereof during the contacting of the wall.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is an overview of an oilfield with a well that
accommodates a toolstring employing embodiments of roller devices
as a conveyance aid.
[0009] FIG. 2A is an enlarged side view of the toolstring of FIG. 1
and highlighting the roller devices thereof.
[0010] FIG. 2B is a front cross sectional view of the toolstring
taken from line 2-2 of FIG. 2A revealing the internal working of a
given roller device.
[0011] FIG. 3A is a side view of the underside of a roller device
of FIGS. 1, 2A and 2B highlighting an embodiment of a journal
bearing therein.
[0012] FIG. 3B is a side view of an alternate embodiment of the
journal bearing of FIG. 3A.
[0013] FIG. 4A is a side view of the toolstring of FIG. 1 employing
an alternate embodiment of roller devices as a conveyance aid.
[0014] FIG. 4B is a front cross sectional view of the toolstring
taken from line 4-4 of FIG. 4A revealing the internal working of a
given roller device.
[0015] FIG. 5 is a flow-chart summarizing an embodiment of
employing roller devices of a toolstring as an aid to conveyance
thereof through a well.
DETAILED DESCRIPTION
[0016] Embodiments are described with reference to certain downhole
applications through deviated well sections that may benefit from
roller devices as an aid to conveyance of a toolstring through the
well. In particular, coiled tubing line is utilized to deliver a
logging and treatment assembly of considerable length to a downhole
location at a depth beyond a non-vertical section of the well.
Though, wireline, drill pipe and other conveyance line types may be
utilized. Regardless, conveyance of the assembly may be aided by
passive rollers thereof as it enters a deviated or tortuous portion
of the non-vertical well section. Of course, a host of other
downhole assemblies and accessories, conveyed by coiled tubing or
otherwise, may be outfitted with conveyance aids as detailed
herein. These may include more interventional devices and
applications such as for perforating or those of a more passive
nature such as for more limited conventional logging. Regardless,
so long as the conveyance aid of the assembly includes roller
devices with cylindrical bearing based mechanisms therein, enhanced
conveyance thereof through the well may be achieved.
[0017] Referring now to FIG. 1, an overview of an oilfield 105 is
shown accommodating a well 180. The well 180 in turn accommodates a
toolstring 101 that employs embodiments of roller devices 100 as a
conveyance aid. That is, as is increasingly the case, the well 180
may be of somewhat sophisticated and non-vertical architecture,
traversing several thousand feet and multiple formation layers 190,
195.
[0018] Thus, in the depicted example, where the toolstring 101 is
conveyed to sufficient depths, it must traverse a bend 197 in the
well 180. Given that the toolstring 101 may be a fairly rigid
structure spanning 50-150 feet or more, roller device or devices
100 such as those depicted may serve as a passive aid in allowing
the toolstirng 101 to round the bend 197. That is, as the rigid
toolstring 101 is advanced by conveyance line such as, but not
limited to, coiled tubing 110 into the bend 197, the well wall 185
may present a tight fit or squeeze to the elongated toolstring 101.
However, the roller devices 100 may passively and responsively roll
against the well wall 185 at this time to further aid in conveyance
of the toolstring 101 beyond the bend 197.
[0019] While rounding the bend 197 with passive assistance of
roller devices 100 appears fairly straight forward, particular
challenges may be presented to the effectiveness of the devices 100
due to the nature of the well environment. For example, as detailed
further below, the toolstring 101 of the example embodiment shown
includes logging devices 160 for obtaining a variety of different
types of well data such as the nature of the surrounding formation
195 or well fluids and other constituents. Indeed, as shown in FIG.
1, a significant amount of debris 199, sand or other particulate
may be found in the well 180. These types of physical corrosives
are not limited to isolated locations but are disbursed throughout
the well 180 and fluids thereof. As a result, roller devices 100 as
shown are fully exposed to such corrosives whenever positioned
downhole. However, as detailed further below, the roller devices
100 are equipped with a unique cylindrical bearing based mechanism
so as to minimize internal exposure and wear from the downhole
environment, thereby extending life and effectiveness as a
conveyance aid.
[0020] Continuing now with reference to FIG. 2A, with added
reference to FIG. 1, an enlarged side view of the toolstring 101 is
shown which highlights the noted roller devices 100. In this
depiction it is apparent that the roller devices are of a profile
that is slightly larger than the diameter (d) of the toolstring
101. Thus, as noted above, the roller devices 100 may passively
contact the well wall 185 as needed (e.g. upon rounding the bend
197). As also indicated above, the toolstring 101 is conveyed via
coiled tubing 110. In the embodiment shown, such operations may
involve surface equipment 125 that includes use of a mobile coiled
tubing truck 135 with reel 144 and control unit 142 for directing
operations. These operations may include the conveyance of the
coiled tubing 110 and toolstring 101 and/or directing of downhole
applications as described further below. As will be appreciated by
those skilled in the art, the conveyance line 110 may comprise
wireline cable, slickline, coiled tubing, drill pipe, or any
suitable conveyance line.
[0021] Continuing with reference to FIG. 1, conveyance includes
routing the coiled tubing 110 and toolstring 101 through a
gooseneck injector 155 at a rig 145 over the well 180. Thus, the
entire assembly may be forcibly advanced through a blowout
preventer 165 and into the vertical portion of the well 180. With
added reference to FIG. 2A, the toolstring 101 may be advanced
within the well 180 as described above for sake of logging and/or
other downhole applications.
[0022] In the embodiment of FIG. 2A, the example toolstring 101
includes traditional logging as well as more interventional tool
segments. For example, imaging 270, gas monitoring 230 and density
acquisition 260 tools may constitute part of the logging device
160. However, a treatment tool 120 for delivering downhole fluids
is also provided. In fact, the toolstring 101 is even outfitted
with a sampling implement 265 for direct interfacing with the well
wall 185 as described further below. That is, in the embodiment
shown, the toolstring is not configured for use in an exclusively
cased well or other more isolated environment. Rather, exposure by
the toolstring 101 and its roller devices 100 to a host of downhole
fluids, debris 199, introduced treatment fluids, and even formation
disturbance is to be expected.
[0023] In light of the vast amount of particle and other expected
downhole exposures, the roller devices 100 are configured with
cylindrical bearing based mechanisms as noted above. More
specifically, with reference to FIG. 2B, a front cross sectional
view of the toolstring 101 is shown taken from line 2-2 of FIG. 2A.
In this manner, the internal workings of a given roller device 100
are revealed. That is, apart from the internal density acquisition
tool 261 and housing 260 at this portion of the logging device 160,
two roller devices 100 are shown along with internals thereof.
[0024] The internals of the roller devices 100 reveal cylindrical
bearing based mechanisms in the form of journal bearings 200. That
is, the indicated housing 260 is equipped with mandrels 215 that
extend therefrom such that circumferential, substantially
monolithic journal bearings 200 may be disposed thereabout. In this
manner, a smooth substantially uninterrupted bearing interface is
provided between the body of each roller device 100 and each
mandrel 215. As a result, exposure and opportunity for particulate,
sand and other debris 199 of the well 180, to interact with such
bearing based mechanisms 200 is kept at a minimum. For example, the
amount of exposed surface to volume area is minimized with use of a
smooth monolithic piece as opposed to conventional ball bearings.
Furthermore, the ability is now afforded to configure the underside
of a body of the roller device 100 to substantially morphologically
match the journal bearing 200. Thus, the bearing 200 may be
substantially isolated from the indicated exposures of concern.
[0025] Continuing with reference to FIG. 2B, the journal bearing
200 may be of a non-corrosive, durable metal so as to even further
extend the life thereof. Additionally, the single-piece nature of
the bearing 200 may afford ease of assembly and maintenance, even
in circumstances where replacement is required. That is, hub screws
240 may be loosened for removal of a hub 210, and the single-piece
bearing 200 dropped out of the roller device 100.
[0026] In the embodiment shown, two rollers 100 in an adjacent
fashion. Thus, when a sampling implement 265 as shown in FIG. 2A is
extended to interface with the well wall 185 (through zone 266), it
may achieve a stable interface along a perpendicular axis 201. That
is, the roller devices 100 may attain a foothold at one side of the
well wall 185 and allow the implement 265 to achieve a largely
sealed engagement with the opposite side of the well wall 185 for
formation sampling therefrom. From a dimensional standpoint this
may be achieved so long as the diameter of the well 180
sufficiently exceeds the width of the toolstring 101, from one 100
roller device to another roller device 100.
[0027] In the embodiment of FIG. 2B, the cylindrical bearing based
mechanism is a journal bearing 200 as described. However, other
forms of cylindrical bearing based mechanisms may alternatively be
employed. For example, in one embodiment, cylindrical roller
bearings may be utilized which provide a degree of both radial and
axial slip. Additionally, as described further below with regard to
FIGS. 4A and 4B, alternate embodiments of roller devices 400, 401
and journal bearing configurations may also be utilized.
[0028] Referring now to FIG. 3A a side view of the underside of a
roller device 100 such as that of FIGS. 1, 2A and 2B is depicted.
In this view, an embodiment of the journal bearing 200 is
highlighted therein. The bearing 200 is of a circumferentially
continuous and monolithic form as described above. Accordingly, it
includes a continuous interior surface 315 for direct interface
with a mandrel 215 as shown in FIG. 2B. Similarly, an exterior
surface 301 is provided for interfacing the body of the roller
device 100.
[0029] With added reference to FIG. 2B, the roller device 100
includes an exterior structure 350 and face 351 that is exposed to
the well 180 for interfacing the well wall 185 as described above.
However, it is also configured with a recess 375 having a portion
for receiving the bearing 200. In the embodiment shown, this recess
375 is stepped down such that the bearing 200 does not occupy the
entirety of the recess 375. Of course, in other embodiments,
alternative recess architecture may be utilized.
[0030] Referring now to FIG. 3B, a side view of an alternate
embodiment of the journal bearing 200 of FIG. 3A is shown. In the
embodiment of FIG. 3B, the journal bearing 200 remains of
continuous circumferential form. However, the bearing is split into
separate monolithic pieces 320, 340 which are utilized together.
More specifically, this results in the noted interior surface 315
and exterior surface 301 being associated with separate pieces 320,
340 of the bearing 200. As a result, forces that are exerted on the
interior surface 315 by the mandrel 215 of FIG. 2B are not
necessarily imparted directly across the entirety of the bearing
200 (e.g. all the way to the other surface 301). Similarly, forces
from interface with the well wall 185 which translate over to the
exterior surface 301 are not automatically imparted directly across
the bearing to the opposite surface 315 (see FIG. 2B).
[0031] The intentional physical disconnect between the journal
pieces 320, 340 as described above results in an interface 330 that
allows for intentional slippage. That is, the reason forces from
one surface 301 or another 315 do not necessarily fully translate
across the entirety of the bearing 200 is due to the allowance of
slippage at the noted interface 330. Once more, this interface 330
is located at an isolated interior of the bearing 200 such that its
presence does not result in a new location of exposure in terms of
well debris and other corrosives of the environment. More
specifically, unlike use of multi-piece spherical bearings for
example, a multi-piece bearing 200 is provided in FIG. 3B that does
not result in added surface exposure to the well environment that
might compromise life of the bearing 200.
[0032] Referring now to FIGS. 4A and 4B, alternate embodiments of
roller devices 400, 401 are shown which may be of a more elongated
400 or dual-sided 401 configurations. These embodiments highlight
the fact that a variety of different configurations of roller
devices may be employed which utilize underlying embodiments of
cylindrical bearing based mechanisms, whether of a journal bearing
type or otherwise.
[0033] Specifically, with reference to FIG. 4A, a side view of the
toolstring 101 of FIG. 2A is shown, again with focus on the
vicinity of the logging device 160 near a sampling tool 465.
However, in contrast to FIG. 2A, the embodiment of FIG. 4A reveals
roller devices 400 which are of a more interior and elongated
configuration with respect to the tool housing 460. That is, as
opposed to being more fully exterior the housing 460, the roller
devices 400 may be recessed to a degree into the housing 460 (see
FIG. 4B).
[0034] By the same token, with reference to FIG. 4B, a roller
device 401 may instead be extended further away from the housing
460 (e.g. and of a dual-sided configuration). Specifically, FIG. 4B
is a front cross-sectional view of the same toolstring 101 of FIG.
4A, taken from line 4-4 thereof. In this view, the internal
workings of roller devices 400, 401 are shown. Wear piece type
journal bearings 410 of a more elongated variety may serve as the
cylindrical bearing based mechanisms as depicted in the partially
sectional view of a dual-sided roller device 401.
[0035] Additionally, with reference to these same roller devices
401, they may be positioned at opposite sides of the housing 460
and of sufficient distance (d') relative a diameter (D) of the well
180 so as to provide a degree of centralization. That is, rather
than attain a footing at a side of the well 180 opposite the
perpendicular axis 411 and zone 466 for the sampling tool 465,
centralization above the `floor` of the well wall 485 may be
attained. So, for example, at the time of sampling, it is less
likely that the elongated interior roller devices 400 would be in
contact with debris at the well wall 185, particularly during
formation sampling. Of course, a variety of additional tool
configurations and roller device types may also be developed which
take advantage of underlying embodiments of cylindrical bearing
based mechanisms.
[0036] Referring now to FIG. 5, a flow-chart summarizing an
embodiment of employing roller devices of a toolstring as an aid to
conveyance is shown. Specifically, the toolstring is deployed into
the well as indicated at 510. The roller device may provide
conveyance assistance as indicated at 530. Further, in recognition
of debris and other wear-inducing factors of the well environment,
a cylindrical bearing based mechanism may be utilized in
conjunction with the device as noted at 550. Thus, as indicated at
570 and 590, an application may be performed with the toolstring
and it may be removed from the well in a reliable and repeatable
manner without undue concern over roller device ineffectiveness,
failure or excessive wear.
[0037] Embodiments described hereinabove include roller-aided
conveyance devices and techniques that may or may not be passive in
nature. However, these roller devices avoid the use of ring
assemblies utilizing a plurality of spherical bearings. Thus,
bearing life is not significantly compromised in light of regular
exposure to the downhole environment. Rather, roller devices and
conveyance may be aided through use of an underlying cylindrical
bearing based mechanism, that may even be of enhanced
manufacturability and comparatively low labor replacement cost. In
addition to aiding conveyance of the toolstring 101, those skilled
in the art will appreciate that the roller device or devices 100,
400, and/or 401 may also prevent or mitigate sticking of the
toolstring 101 while the toolstring 101 is stationary, such as when
the sampling implement 265 or sampling tool 465 is directly
interfacing with the well wall 185 for extended periods of time, as
the roller device or devices 100, 400, and/or 401 may provide a
mechanism for passively and/or responsively rolling against a well
wall 185 and/or a mudcake formed thereon.
[0038] The preceding description has been presented with reference
to presently preferred embodiments. Persons skilled in the art and
technology to which these embodiments pertain will appreciate that
alterations and changes in the described structures and methods of
operation may be practiced without meaningfully departing from the
principle, and scope of these embodiments. Regardless, the
foregoing description should not be read as pertaining only to the
precise structures described and shown in the accompanying
drawings, but rather should be read as consistent with and as
support for the following claims, which are to have their fullest
and fairest scope.
* * * * *