U.S. patent application number 14/784113 was filed with the patent office on 2016-03-17 for anchor ring assembly.
The applicant listed for this patent is REACTIVE DOWNHOLE TOOLS LIMITED. Invention is credited to Mike Allen, Christopher George Barnes, David Matthew Hare.
Application Number | 20160076324 14/784113 |
Document ID | / |
Family ID | 48537384 |
Filed Date | 2016-03-17 |
United States Patent
Application |
20160076324 |
Kind Code |
A1 |
Allen; Mike ; et
al. |
March 17, 2016 |
ANCHOR RING ASSEMBLY
Abstract
An anchor ring assembly for anchoring to a mandrel includes an
annular housing which defines a through bore to permit mounting on
a mandrel. A plurality of slips are circumferentially arranged
within the through bore of the housing, and a plurality of
activator members extend from an external surface of the housing to
engage the slips. The activator members are adjustable relative to
the housing to extend the slips radially inwardly to engage and
grip a mandrel.
Inventors: |
Allen; Mike; (Insch, GB)
; Hare; David Matthew; (Aberdeen, GB) ; Barnes;
Christopher George; (Aberdeenshire, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
REACTIVE DOWNHOLE TOOLS LIMITED |
Aberdeen |
|
GB |
|
|
Family ID: |
48537384 |
Appl. No.: |
14/784113 |
Filed: |
April 17, 2014 |
PCT Filed: |
April 17, 2014 |
PCT NO: |
PCT/GB2014/051210 |
371 Date: |
October 13, 2015 |
Current U.S.
Class: |
166/381 ;
166/118; 166/179; 166/206; 166/214 |
Current CPC
Class: |
E21B 17/10 20130101;
E21B 23/06 20130101; E21B 33/129 20130101; E21B 33/126 20130101;
E21B 33/1208 20130101 |
International
Class: |
E21B 23/06 20060101
E21B023/06; E21B 33/129 20060101 E21B033/129 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 17, 2013 |
GB |
1306968.7 |
Claims
1. An anchor ring assembly for anchoring to a mandrel, comprising:
an annular housing defining a through bore to permit mounting on a
mandrel; a plurality of slips circumferentially arranged within the
through bore of the housing; and a plurality of activator members
extending from an external surface of the housing to engage the
slips, wherein the activator members are adjustable relative to the
housing to extend the slips radially inwardly to engage and grip a
mandrel.
2. The anchor ring assembly according to claim 1, wherein the
activator members comprise activator screws threadedly engaged with
the housing to permit adjustment to extend the respective
slips.
3. The anchor ring assembly according to claim 1, wherein a single
activator member is provided for each slip.
4. The anchor ring assembly according to claim 1, wherein the
activator member engage respective rear faces of the slips.
5. The anchor ring assembly according to claim 1, wherein an
activator member is configured to engage a respective slip
generally centrally thereof.
6. The anchor ring assembly according to claim 1, wherein at least
one of: at least one slip defines an engagement profile on a rear
surface thereof to be engaged by a respective activator member; at
least one slip comprises a gripping profile on inwardly facing
surface thereof for use in gripping an outer surface of a mandrel;
at least one slip comprises gripping teeth; at least one slip
comprises first and second sets of gripping teeth; at least one
slip comprises first and second sets of gripping teeth and the
first and second sets of gripping teeth are orientated in opposing
directions; at least one slip defines a curved profile.
7-11. (canceled)
12. The anchor ring assembly according to claim 1, comprising a
plurality of spacer ribs circumferentially distributed around the
through bore of the housing, wherein adjacent slips are separated
by a respective spacer rib.
13. The anchor ring assembly according to claim 12, wherein at
least one of: each spacer rib extends generally axially relative to
the housing; adjacent spacer ribs define a pocket therebetween for
receiving a respective slip; each spacer rib defines tapered side
faces, wherein the circumferential faces of each slip define
corresponding tapered faces; at least two circumferentially
adjacent spacer ribs retain a slip positioned therebetween within
the assembly; at least two circumferentially adjacent spacer ribs
define a limit of radial movement of a slip positioned
therebetween; at least two circumferentially adjacent ribs define a
minimum circumferential separation distance which is smaller than a
circumferential dimension of a slip positioned therebetween: at
least two circumferentially adjacent ribs define a minimum
circumferential separation distance which is smaller than a maximum
circumferential dimension of a slip positioned therebetween; at
least two circumferentially adjacent ribs collectively define a
retaining profile configured to retain a slip therebetween.
14-20. (canceled)
21. The anchor ring assembly according to claim 1, comprising a
retaining arrangement configured to retain one or more slips
mounted within the housing.
22. The anchor ring assembly according to claim 21, wherein at
least one of: the retaining arrangement is configured to apply a
retaining force to one or more slips to retain said slips within
the housing; the retaining arrangement biases one or more slips
towards a retracted configuration; the retaining arrangement is
mounted radially inwardly of the slips; one or more slips define a
groove formed in an inner surface thereof for accommodating a
retaining arrangement; each slip defines a groove, wherein when the
slips are mounted within the housing each individual groove is
aligned to receive the retaining arrangement; the retaining
arrangement is mounted axially centrally of the slips; the
retaining arrangement comprises a spring member or element, such as
a split spring element; at least one slip comprises first and
second axially separated gripping profiles, wherein a retaining
arrangement is located between said first and second profiles.
23-29. (canceled)
30. The anchor ring assembly according to claim 1, the annular
housing defines a circumferential groove formed in an inner surface
thereof, wherein said groove is configured to accommodate one or
more slips.
31. The anchor ring assembly according to claim 30, wherein at
least one of: the circumferential groove is profiled, wherein at
least one slip defines a corresponding profile to permit
appropriate fitting of the slips within the groove; at least one
axial face of the groove is tapered, and at least one axial face of
at east one slip is tapered to correspond and engage the tapered
axial face of the groove; opposing axial faces of the groove, and
opposing axial faces of at least one slip are tapered.
32-33. (canceled)
34. The anchor ring assembly according to claim 1, wherein at least
one of: at least one axial end face of the housing defines a load
surface; and at least one axial end face of the housing is tapered
relative to a central axis of the housing.
35. (canceled)
36. The anchor ring assembly according to claim 1, wherein at least
one axial end face of the housing comprises an axial extension
configured to engage an external component, such as a sealing
element.
37. The anchor ring assembly according to claim 1, comprising a
sealing arrangement configured to provide a seal with a
mandrel.
38. The anchor ring assembly according to claim 1, comprising a
sealing element extending from one axial end of the housing.
39. A method for anchoring to a mandrel, comprising: mounting an
anchor ring assembly on a mandrel, wherein the anchor ring assembly
comprises an annular housing and a plurality of slips
circumferentially arranged within a through bore of the housing;
and adjusting a plurality of activator members which extend from an
outer surface of the housing to engage the respective slips to
extend the slips radially inwardly to engage and grip the
mandrel.
40. A sealing assembly for use in providing a seal in an annulus
between a mandrel and a bore wall, comprising: an annular housing
defining a through bore to permit mounting on a mandrel; a
plurality of slips circumferentially arranged within the through
bore of the housing; a plurality of activator members extending
from an external surface of the housing to engage the slips,
wherein the activator members are adjustable relative to the
housing to extend the slips radially inwardly to engage and grip a
mandrel; and a sealing element extending from one axial end of the
housing.
41. The sealing assembly according to claim 40, comprising two
annular housings located at opposite ends of the sealing element,
wherein each annular housing accommodates slips for anchoring to a
mandrel.
42. A sealing assembly comprising: a mandrel; and an annular
sealing element bonded to the outer surface of the mandrel, wherein
the sealing element comprises a swellable material configured to
swell upon exposure to an activator.
43. A sealing assembly comprising: a support member; an outer
swellable sealing element mounted on an outer surface of the
support member; and an inner swellable sealing element mounted on
an inner surface of the support member, wherein the outer swellable
sealing element is configured to swell to define a seal between the
support member and a bore wall, and the inner swellable sealing
element is configured to swell to define a seal between the support
member and a mandrel.
44. The sealing assembly according to claim 43, configured to be
mounted on a mandrel.
45. The sealing assembly according to claim 43, wherein at least
one of: the support member comprise a metallic support member: the
support member is generally cylindrical; the support member
comprises one or more perforations through its wall structure; the
support member comprises one or more perforations through its wall
structure, the inner and outer sealing elements engage, for example
by being integrally formed, via the perforations.
46-48. (canceled)
49. The sealing assembly according to claim 43, comprising one or
more end rings.
50. The sealing assembly according to claim 49, wherein at least
one of: the support member engages at least one end ring; the outer
sealing element engages an axial end face or surface of an end
ring; the inner sealing element engages an axial end face or
surface of an end ring; the inner sealing element engages an inner
circumferential face of an end ring; and an end ring is secured
relative to the support member via one or more screws.
51-54. (canceled)
55. A sealing assembly for use in providing a seal in an annulus
between a mandrel and a bore wall, comprising: an annular housing
defining a through bore to permit mounting on a mandrel, wherein
the annular housing includes a sealing arrangement for providing a
seal between the annular housing and a mandrel; a plurality of
slips circumferentially arranged within the housing, wherein the
slips are configured to be extended radially inwardly to engage and
grip a mandrel; and a cup sealing element extending from one axial
end of the housing.
56. The sealing assembly according to claim 55, wherein one axial
end of the housing includes an axial extension configured to engage
the cup sealing element.
57. The sealing assembly according to claim 55, wherein the cup
sealing element is bonded to one axial end of the housing.
58. The anchor ring assembly according to claim 1, wherein the
activator members are adjustable radially inwards relative to the
housing to extend the slips radially inwardly to engage and grip a
mandrel.
Description
REFERENCE TO RELATED APPLICATIONS
[0001] This application is a United States National Phase
application of PCT Application No. PCT/GB2014/051210 filed on Apr.
17, 2014, which claims priority to United Kingdom Application No.
1306968.7 filed on Apr. 17, 2013.
FIELD OF THE INVENTION
[0002] The present invention relates to an anchor ring assembly for
anchoring to a mandrel, for example to provide end support to seal,
such as a packer for providing a seal in a wellbore annulus.
BACKGROUND TO THE INVENTION
[0003] Many industries may require components to be located and
secured to a mandrel, such as a tubular body. For example, in the
oil and gas industry, annular seals are frequently employed which
are mounted on a mandrel and function to extend radially outwardly
from the mandrel to engage a bore wall, thus sealing the annulus
between the mandrel and bore wall. Such a seal is often referred to
as a packer. Known packers or seals in the oil and gas industry may
be activated in a number of ways to be extended radially outwardly,
for example by being axially compressed, by swelling, by inflation
or the like.
[0004] In many seal designs the sealing component is located on a
mandrel against metal end rings. Such end rings are located at one
or both axial ends of a sealing body, and may be secured to the
mandrel by welding, via set screws or the like.
[0005] The end rings may anchor a sealing component to the mandrel.
Additionally, such end rings may also function to prevent unwanted
axial deformation of the sealing component, for example due to
extrusion when exposed to a pressure differential, which might
otherwise compromise the integrity of any established seal. This
may be of particular importance in swellable seal designs, wherein
the end rings function to prevent or minimise axial swelling, such
that the swelling of the seal may be restricted primarily to the
radial direction.
[0006] Of critical importance in the design of end rings is their
ability to provide a sufficient anchor to resist any displacing
forces which might be experienced, and in some instances a poorly
anchored end ring may result in failure of any associated seal.
SUMMARY OF THE INVENTION
[0007] According to a first aspect of the present invention, there
is provided an anchor ring assembly for anchoring to a mandrel,
including an annular housing defining a through bore to permit
mounting on a mandrel, a plurality of slips circumferentially
arranged within the through bore of the housing, and a plurality of
activator members extending from an external surface of the housing
to engage the slips. The activator members are adjustable relative
to the housing to extend the slips radially inwardly to engage and
grip a mandrel.
[0008] In use, the anchor ring assembly may be mounted on a mandrel
and located in a desired position, with the activator members then
adjusted relative to the housing to extend the slips radially
inwardly to engage and grip the outer surface of the mandrel, thus
anchoring or locking the anchor ring assembly to the mandrel.
[0009] The anchor ring assembly may be used in various
applications. For example, the anchor ring assembly may be for use
in defining a no-go profile on a mandrel.
[0010] The anchor ring assembly may define or function as an end
ring for a seal element, such as an annular seal element, swellable
seal element, axially compressible seal element, cup seal element
and/or the like. The anchor ring assembly may be configured to
resist axially applied forces, such as axial pressure forces
established by exposure to a pressure differential across a seal
element. Such resistance to axial forces may permit the anchor ring
assembly to provide support to assist the seal element to resist
extrusion.
[0011] The anchor ring assembly may be configured to provide
support to a seal element. The anchor ring assembly may be
configured to secure a seal element on or relative to a
mandrel.
[0012] The anchor ring assembly may be suitable for use in securing
to a mandrel in the form of a tubular, such as an oilfield tubular,
for example a casing tubular, liner tubular, production tubular,
tool sleeve or the like.
[0013] The activator members may include activator screws
threadedly engaged with the housing to permit adjustment to extend
the respective slips.
[0014] A single activator member may be provided for each slip. In
other embodiments one slip may be associated with multiple
activator members.
[0015] The activator members may be configured to engage respective
rear faces of the slips. An activator member may be configured to
abut a respective slip. In such an arrangement adjustment of an
activator member relative to the housing may function to extend an
associated slip. In some embodiments an activator member may be
secured to a respective slip. Such an arrangement may permit the
activator member to be adjusted relative to the housing to permit
both extension and retraction of the associated slip.
[0016] An activator member may be configured to engage a respective
slip generally centrally thereof. For example, an activator member
may be configured to engage a respective slip at an axial and/or
circumferential central region of said slip. Engagement of an
activator member generally centrally of a respective slip may
permit a degree of self-adjustment of said slip, for example to
self-align with an outer surface of a mandrel. In one embodiment
engagement of an activator member generally centrally of an
associated slip may permit said slip to pivot relative to the
housing. Such pivoting may be possible in multiple directions. Such
an arrangement may provide a self aligning function of the
slips.
[0017] One or more slips may define an engagement profile on a rear
surface thereof and configured to be engaged by a respective
activator member. For example, such an engagement profile may
include a recess, dimple, blind hole, channel or the like.
[0018] One or more slips may include a gripping profile on inwardly
facing surfaces thereof for use in gripping an outer surface of a
mandrel. Such a gripping profile may assist to increase a
connection force between the anchor ring assembly and a mandrel.
The gripping profile may be defined by any suitable structure, such
as by individual teeth or ribs, by a surface roughness, by a
knurled profile, by use of inserted material such as a carbine or
the like.
[0019] One or more slips may include first and second sets of
gripping teeth. Said sets of gripping teeth may be orientated in
opposing directions. Such an arrangement may permit the first set
of gripping teeth to preferentially resist forces applied in one
direction, such as one axial direction, and the second set of
gripping teeth to preferentially resist forces applied in an
opposite direction, such as an opposite axial direction. The first
set of gripping teeth may be located on one axial side of a slip,
and the second set of gripping teeth may be located on an opposite
axial side of the slip.
[0020] One or more slips may facilitate an increase in an
engagement area between the anchor ring assembly and a mandrel,
which may permit a more robust connection to be achieved. Further,
the use of slips which are extended to engage the outer surface of
the mandrel may eliminate or minimise the requirement to alter the
form of the mandrel to accommodate an anchor ring assembly.
[0021] One or more slips may be profiled to correspond to a profile
of a mandrel. For example, one or more slips may be generally
curved to permit engagement with a cylindrical mandrel. One or more
slips may be curved to define a circumferential segment.
[0022] At least two, and in some embodiments all slips may be
arranged such that circumferential ends thereof may be positioned
generally adjacent to each other. This arrangement may maximise the
total circumferential slip surface area which may engage a mandrel,
thus permitting a more robust connection to be achieved.
[0023] The anchor ring assembly may include a plurality of spacer
ribs circumferentially distributed around the through bore of the
housing, wherein adjacent slips are separated by a respective
spacer rib. Each spacer rib may extend generally axially relative
to the housing. Circumferential ends of the slips may be positioned
adjacent respective spacer ribs.
[0024] One or more spacer ribs may be integrally formed with the
housing.
[0025] One or more spacer ribs may be separately formed and secured
to the housing, for example via screws or the like.
[0026] Adjacent spacer ribs may define a pocket therebetween for
receiving a respective slip. Each spacer rib may define tapered
side faces, wherein the circumferential faces of each slip may
define corresponding tapered faces. Such an arrangement may
facilitate radial extension and retraction of the slips, with
minimal interference from the spacer ribs. Furthermore, such
tapered faces of the slips and spacer ribs may permit each slip to
be appropriately guided into the circumferential groove of the
housing upon retraction of said slips.
[0027] At least two circumferentially adjacent spacer ribs may
secure a slip positioned therebetween. At least two
circumferentially adjacent spacer ribs may define a limit of radial
movement, such as inward radial movement, of a slip positioned
therebetween. In one embodiment at least two circumferentially
adjacent ribs may define a minimum circumferential separation
distance which is smaller than a circumferential dimension of a
slip positioned therebetween. At least two circumferentially
adjacent ribs may define a minimum circumferential separation
distance which is smaller than a maximum circumferential dimension
of a slip positioned therebetween. In such an arrangement, once the
slip is interposed between adjacent ribs, said ribs will prevent
said slip from being fully radially removed from the anchor ring
assembly.
[0028] At least two circumferentially adjacent ribs may
collectively define a retaining profile configured to retain a slip
therebetween.
[0029] The anchor ring assembly may include a retaining arrangement
configured to retain one or more slips mounted within the housing.
The retaining arrangement may be configured to retain all slips
within the housing. The retaining arrangement may be configured to
apply a retaining force to one or more slips to retain said slips
within the housing. Extension of one or more slips radially
inwardly may be achieved against this retaining force. The
retaining arrangement may be configured to bias one or more slips
towards a retracted configuration. In such an arrangement
adjustment of one or more activator members in a direction to
extend the associated one or more slips may act against the bias of
the retaining arrangement. Further, in such an arrangement
adjustment of one or more activator members in a direction to
retract the associated one or more slips may permit the bias of the
retaining arrangement to cause said slips to be retracted.
[0030] The retaining arrangement may be mounted radially inwardly
of the slips.
[0031] In one embodiment one or more slips may define a groove
formed in an inner surface thereof for accommodating a retaining
arrangement. A plurality, for example all, slips may define a
groove, wherein when the slips are mounted within the housing, each
individual groove is aligned to receive the retaining arrangement.
Such a collective groove may be generally circumferential. In some
embodiments such a collective groove may be helical.
[0032] A groove provided in one or more slips for accommodating a
retaining arrangement may define a groove width which is larger
than the corresponding width of the retaining arrangement. Such an
arrangement may permit a degree of relative motion between the slip
or slips and the retaining arrangement, for example to permit
compliance of the slip or slips during clamping against a
mandrel.
[0033] The retaining arrangement may be configured to be mounted
axially centrally of the slips. Such an arrangement may permit the
slips to be self-aligning, for example to accommodate the profile
of a mandrel. Such an arrangement may permit each slip to pivot
about the retaining arrangement, which may provide a self-alignment
function.
[0034] The retaining arrangement may include a single retaining
element.
[0035] The retaining arrangement may include a spring member or
element.
[0036] The retaining arrangement may define a split ring spring
element configured to provide an outwardly directed retaining
force.
[0037] At least one slip may define or include first and second
gripping profiles, wherein a retaining arrangement is located
between said first and second profiles. In such an embodiment the
retaining arrangement may not interfere with the gripping function
of the slips.
[0038] The annular housing may define a circumferential groove
formed in an inner surface thereof, wherein said groove is
configured to accommodate one or more slips. The circumferential
groove may be circumferentially continuous. Alternatively, the
circumferential groove may be circumferentially discontinuous. For
example, multiple discrete grooves or recesses may be provided
within the housing. Such discrete grooves or recesses may define a
plurality of circumferentially arranged pockets each for receiving
or accommodating one or more slips.
[0039] The circumferential groove of the housing may be profiled,
wherein at least one slip defines a corresponding profile to permit
appropriate fitting of the slips within the groove.
[0040] The circumferential groove of the housing may be defined
between opposing axial faces. Opposing axial ends of at least one
slip may be profiled to correspond with the axial faces of the
housing groove.
[0041] At least one axial face of the groove may extend generally
perpendicular relative to a central axis of the housing. Such an
axial face may define an annular shoulder. Such an axial face may
permit load transference between the housing and at least one
slip.
[0042] At least one axial face of the groove may be tapered. That
is, at least one axial face of the groove may be tapered or
obliquely aligned relative to a central axis of the housing. At
least one axial face of at least one slip may be tapered to
correspond and engage the tapered axial face of the groove. In use,
an axial load applied on the housing, for example from an external
component, such as a seal element, may be transmitted to at least
one slip via the respective tapered faces, thus applying an inward
radial force on said at least one slip. Such an inward radial force
may function to increase the gripping force of the slips against a
mandrel. Accordingly, increasing axial load applied on the housing,
for example from an external component, may result in the gripping
force of the slips being increased. As such, the anchor ring
assembly may automatically respond to changes in applied axial
forces.
[0043] Opposing axial faces of the groove, and opposing axial faces
of at least one slip may be tapered. Such an arrangement may permit
an increase in gripping force to be achieved in the event of an
axial load applied in opposite axial directions.
[0044] At least one axial end face of the housing may be configured
to be engaged by an external component, such as a seal component or
element. At least one axial end face of the housing may define a
load surface, such as a load shoulder or the like. Such a load
surface may be configured for transmission of force from an
external component or environment into the anchor ring
assembly.
[0045] At least one axial end face of the housing may be tapered
relative to a central axis of the housing. Such a tapered surface
may facilitate or assist with insertion of the anchor ring
assembly, for example when mounted on a mandrel, into a bore, such
as a well bore.
[0046] At least one axial end face of the housing may be generally
perpendicular to central axis of housing.
[0047] At least one axial end face of the housing may be configured
to be sealingly engaged with an external component, such as a
sealing element.
[0048] At least one axial end face of the housing may be configured
to be bonded to an external component, such as a seal component or
element.
[0049] At least one axial end face of the housing may be configured
to define a profile configured to permit engagement with a
corresponding profile on an external component, such as a sealing
element.
[0050] At least one axial end face of the housing may include an
axial extension configured to engage an external component, such as
a sealing element, for example a cup seal element. The axial
extension may increase a surface area of contact between an
external component and the housing. The axial extension may be
configured to at least partially define a sealed surface between
the housing and an external component. The axial extension may be
configured to at least partially define a bonded surface between
the housing and an external component.
[0051] The anchor ring assembly may include a sealing arrangement
configured to provide a seal with a mandrel. The sealing
arrangement may be configured to provide a seal between the housing
and a mandrel. The seal arrangement may include a mechanical seal,
such as an o-ring seal or the like. An inner surface of the housing
may define a circumferential groove configured to accommodate a
seal, such as an o- ring seal. An inner surface of the housing may
define multiple circumferential grooves configured to accommodate
respective seals.
[0052] The sealing arrangement may be configured to provide a seal
between the slips and a mandrel. The slips may define one or more
grooves configured to collectively accommodate a seal, such as an
o-ring seal.
[0053] A retaining arrangement configured to retain the slips
within the circumferential groove of the housing may also define a
sealing arrangement configured to provide a seal against a
mandrel.
[0054] The anchor ring assembly may include a sealing element
extending from one axial end of the housing. The sealing element
may be configured for use in providing a seal in an annulus defined
between a mandrel and an outer bore wall, such as an open drilled
bore wall, the wall of a casing, pipeline or the like. The anchor
ring assembly, and in particular the annular housing may provide
axial support to such a sealing element, for example to help resist
extrusion of the sealing element when exposed to a pressure
differential.
[0055] The sealing element may include an annular sealing
element.
[0056] The sealing element may include a swellable material
configured to swell upon exposure to an activator, such as oil
and/or water. In such an arrangement the anchor ring assembly, and
in particular the housing when anchored to a mandrel via the slips,
may function to restrict swelling of the swellable material in an
axial direction. In this way, swelling may be achieved primarily in
a radial direction to facilitate sealing between the mandrel and an
outer bore wall.
[0057] The sealing element may include an axially compressible
sealing element. In such an arrangement the anchor ring assembly,
and in particular the housing when anchored to a mandrel via the
slips, may define a reaction point against which such a
compressible sealing element may be compressed.
[0058] The sealing element may include a cup seal sealing element.
One axial end of the cup sealing element may be engaged with the
housing, for example sealingly engaged, and an opposite axial end
of the cup sealing element may be free from support, so as to
permit the seal element to function as a cup seal.
[0059] The sealing element may be bonded directly to a mandrel.
[0060] The sealing element may include a support sleeve, an outer
sealing material mounted on an outer surface of the support sleeve,
and an inner sealing material mounted on an inner surface of the
support sleeve.
[0061] In such an arrangement the outer sealing material may be
configured to establish a seal with a wall of a bore, and the inner
sealing material may be configured to establish a seal against a
mandrel.
[0062] The support sleeve may extend along the entire axial length
of the sealing element. In some embodiments the support sleeve may
extend along a partial axial length of the sealing element.
[0063] The support sleeve may be fixed to the anchor ring assembly,
for example to the housing of the anchor ring assembly.
[0064] According to a second aspect of the present invention, there
is provided a method for anchoring to a mandrel, including mounting
an anchor ring assembly on a mandrel, the anchor ring assembly
including an annular housing and a plurality of slips
circumferentially arranged within a through bore of the housing,
and adjusting a plurality of activator members which extend from an
outer surface of the housing to engage the respective slips to
extend the slips radially inwardly to engage and grip the
mandrel.
[0065] The anchor ring assembly according to the first aspect may
be utilized in the method according to the second aspect.
[0066] According to a third aspect of the present invention, there
is provided a sealing assembly for use in providing a seal in an
annulus between a mandrel and a bore wall, including:
[0067] an annular housing defining a through bore to permit
mounting on a mandrel;
[0068] a plurality of slips circumferentially arranged within the
through bore of the housing;
[0069] a plurality of activator members extending from an external
surface of the housing to engage the slips, wherein the activator
members are adjustable relative to the housing to extend the slips
radially inwardly to engage and grip a mandrel; and
[0070] a sealing element extending from one axial end of the
housing.
[0071] The sealing assembly may include two annular housings
located at opposite ends of the sealing element, wherein each
annular housing accommodates slips for anchoring to a mandrel. In
such an arrangement the sealing element may be supported at
opposing ends.
[0072] The sealing assembly may include a single housing, such that
the sealing element is supported at a single end.
[0073] The sealing element may include any suitable type of sealing
element, such as a swellable sealing element, compressible sealing
element, a cup sealing element or the like.
[0074] The housing may include an axial extension extending from
one axial end face thereof to permit engagement with the sealing
element.
[0075] The sealing assembly may include an anchor ring assembly
according to the first aspect.
[0076] According to a fourth aspect of the present invention, there
is provided a sealing assembly including: a mandrel; an annular
sealing element bonded to the outer surface of the mandrel, wherein
the sealing element includes a swellable material configured to
swell upon exposure to an activator.
[0077] The activator may include water, oil, gas or the like.
[0078] According to a fifth aspect of the present invention, there
is provided a sealing assembly including a support member, an outer
swellable sealing element mounted on an outer surface of the
support member, and an inner swellable sealing element mounted on
an inner surface of the support member. The outer swellable sealing
element is configured to swell to define a seal between the support
member and a bore wall, and the inner swellable sealing element is
configured to swell to define a seal between the support member and
a mandrel.
[0079] The sealing assembly may be configured to be mounted on a
mandrel, for example to be slipped on to one end of a mandrel.
[0080] The support member may include a metallic support member.
The support member may be generally cylindrical. The support member
may include one or more perforations through its wall structure.
The inner and outer sealing elements may engage each other via
these perforations. In one embodiment the inner and outer sealing
elements may be integrated, for example continuous, via these
perforations.
[0081] The sealing assembly may include one or more end rings. The
support member may be secured or at least engage at least one end
ring.
[0082] The outer sealing element may engage an axial end face or
surface of an end ring.
[0083] The inner sealing element may engage an axial end face or
surface of an end ring.
[0084] The inner sealing element may engage an inner
circumferential face of an end ring. Such an arrangement may permit
the inner sealing element to also establish a seal between an end
ring and a mandrel.
[0085] An end ring may be configured to be secured relative to the
support member via one or more screws, such as set screws, grub
screws or the like.
[0086] An end ring may include an anchor ring assembly according to
the first aspect.
[0087] According to a sixth aspect of the present invention, there
is provided a sealing assembly for use in providing a seal in an
annulus between a mandrel and a bore wall, including an annular
housing defining a through bore to permit mounting on a mandrel,
the annular housing including a sealing arrangement for providing a
seal between the annular housing and a mandrel, a plurality of
slips circumferentially arranged within the housing, the slips
configured to be extended radially inwardly to engage and grip a
mandrel, and a cup sealing element extending from one axial end of
the housing.
[0088] One axial end of the housing may include an axial extension
configured to engage the cup sealing element.
[0089] The cup sealing element may be bonded to one axial end of
the housing.
[0090] The sealing arrangement provided between the housing and a
mandrel may include one or more mechanical seals, such as o-ring
seals.
[0091] The sealing assembly may include an anchor ring assembly
according to the first aspect.
[0092] Features defined in relation to one aspect may be provided
in combination with any other aspect. It should be understood that
the features defined above in accordance with any aspect of the
present invention or below in relation to any specific embodiment
of the invention may be utilized, either alone or in combination
with any other defined feature, in any other aspect or embodiment
of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0093] These and other aspects of the present invention will now be
described, by way of example only, with reference to the
accompanying drawings, in which:
[0094] FIG. 1 is a perspective view of an anchor ring assembly
according to an embodiment of the present invention;
[0095] FIG. 2 is a side view of the anchor ring assembly of FIG. 1,
shown mounted on a mandrel, wherein the mandrel is illustrated in
broken outline;
[0096] FIG. 3 is a cross sectional view of the anchor ring assembly
taken through line 3-3 of FIG. 2, with the mandrel removed for
clarity;
[0097] FIG. 4 is a cross sectional view of the anchor ring assembly
taken through line 4-4 of FIG. 2, with the mandrel removed for
clarity;
[0098] FIG. 5 is a perspective view of a single slip which forms
part of the anchor ring assembly;
[0099] FIG. 6 is a cross-section view of the anchor ring assembly
taken through line 6-6 of FIG. 2, with the mandrel removed for
clarity;
[0100] FIG. 7 illustrates a sealing assembly according to an
embodiment of the present invention, which incorporates a pair of
anchor ring assemblies;
[0101] FIG. 8 illustrates a sealing assembly according to another
embodiment of the present invention, which incorporates a pair of
anchor ring assemblies;
[0102] FIG. 9 is a cross sectional view of a portion of an anchor
ring assembly according to an alternative embodiment of the present
invention;
[0103] FIG. 10 is a perspective view of an anchor ring assembly
according to an alternative embodiment of the present
invention;
[0104] FIG. 11 is a side view of the anchor ring assembly of FIG.
10, shown mounted on a mandrel, wherein the mandrel is illustrated
in broken outline;
[0105] FIG. 12 is a cross sectional view of the anchor ring
assembly taken through line 12-12 of FIG. 11, with the mandrel
removed for clarity;
[0106] FIG. 13 is an enlarged view of a portion of the anchor ring
assembly as shown in the section of FIG. 12, with a slip
removed;
[0107] FIG. 14 illustrates a sealing assembly according to an
embodiment of the present invention, with an end ring removed for
clarity; and
[0108] FIG. 15 illustrates a sealing assembly according to an
alternative embodiment of the present invention.
DETAILED DESCRIPTION OF THE DRAWINGS
[0109] A perspective view of an anchor ring assembly, generally
identified by reference numeral 10, is shown in FIG. 1, and a side
view of the same assembly 10 is illustrated in FIG. 2. As will be
described in detail below, the anchor ring assembly 10 is for use
in anchoring to a mandrel 12, which is illustrated in FIG. 2 in
broken outline. The mandrel 12 may include a tubular member, such
as an oilfield tubular. The anchor ring assembly 10 may have
utility in multiple applications. In some of the examples below the
assembly 10 is utilized to function as an end ring in a sealing
assembly, such as a packer assembly.
[0110] The anchor ring assembly 10 includes an annular housing 14
which defines a throughbore 15 to permit the housing 14 to be
mounted on the mandrel 12. The assembly 10 further includes a
plurality of slips 16 (five in the embodiment shown) which are
circumferentially arranged within a circumferential groove 18
formed in an inner surface of the housing 14, wherein the slips 16
are each located between circumferentially arranged spacer ribs 20
which are secured to the housing via screws 22, as also illustrated
in FIG. 3 which is a cross-sectional view through line 3-3 of FIG.
2. Each rib 20 includes tapered side faces 24, and the
circumferential end faces 26 of each slip 16 correspond such that
the slips 16 may be permitted to be displaced radially inwardly
without interference from the ribs 20. Furthermore, the
corresponding faces 24, 26 of the ribs 20 and slips 16 may function
to align the slips 16 within the circumferential groove 18 of the
housing 14 when moved towards a retracted position.
[0111] A plurality of activator members in the form of screws 28
extend from the outer surface of the housing 14 and engage the rear
faces of the respective slips 16, as shown in FIG. 4 which is a
cross sectional view through line 4-4 of FIG. 2. Adjustment of the
activator screws 28 relative to the housing 14 permits the slips 16
to be extended radially inwardly to grip the outer surface of the
mandrel 12 and thus anchor the assembly 10 thereto.
[0112] A single activator screw 28 is provided for each slip 16,
and each screw 28 engages the rear face of a slip 16 generally
centrally thereof. This arrangement permits the slips 16 to pivot
about the contact point with the screws 28, which assists with
self-alignment of the slips 16 with the mandrel 12.
[0113] In the present embodiment, one axial end face 30 of the
housing 14 is generally perpendicular to a central axis of the
housing 14. As best illustrated in FIG. 2, such a perpendicular end
face 30 defines an annular shoulder relative to the mandrel 12.
This annular shoulder or face 30 may be used to support an adjacent
external component, such as a sealing element for defining a seal
between the mandrel 12 and a bore wall.
[0114] An opposite axial end face 32 of the housing 14 defines a
tapered surface. This may facilitate insertion of the mandrel 12
and mounted anchor ring assembly 10 into a bore, for example to
minimise snagging of the assembly 10 with any restrictions in such
a bore.
[0115] An individual slip 16 is illustrated in FIG. 5, reference to
which is additionally made. Each slip 16 is generally arcuate or
curved in form and includes first and second sets of gripping
profiles in the form of sets of teeth 34, 36 which function to
increase the anchoring force against the mandrel 12. In the
embodiment shown, the first and second sets of gripping teeth 34,
36 are orientated in opposing directions, which permits the first
set of gripping teeth 34 to preferentially resist forces applied in
one axial direction, and the second set of gripping teeth 36 to
preferentially resist forces applied in an opposite axial
direction.
[0116] Each slip 16 includes a central groove 38 which are aligned
when the slips 16 are mounted within the housing 14. The grooves 38
are configured to receive a split ring spring member 40, as
illustrated in FIGS. 1 and 4, which functions to retain each slip
16 within the circumferential groove 18 of the housing 14. Further,
the spring member 40 applies a biasing force against the slips 16
to bias said slips towards a retracted position, for example when
the activator screws 28 are adjusted relative to the housing 14 to
permit retraction of the slips 16. In some embodiments the grooves
38 each are wider than the spring member 40 in the axial direction.
Such an arrangement may permit a degree of relative movement
therebetween.
[0117] Reference is now additionally made to FIG. 6 which is a
cross sectional view of the assembly 10 taken through line 6-6 of
FIG. 2. As illustrated, the circumferential groove 18 formed in the
housing includes opposing tapered side faces 42. Further, each slip
16 includes corresponding tapered side faces 44. In use, an axial
load applied on the housing 14, for example from an external
component, such as a seal element, may be transmitted to the slips
16 via the respective tapered faces 42, 44, thus applying an inward
radial force on the slips 16. Such an inward radial force may
function to increase the gripping force of the slips 16 against the
mandrel 12. Accordingly, increasing axial load applied on the
housing 14, for example from an external component, may result in
the gripping force of the slips 16 being increased. As such, the
anchor ring assembly 10 may automatically respond to changes in
applied axial forces.
[0118] As noted above, the anchor ring assembly 10 may be used in
multiple applications, including as an end ring within a sealing
assembly, such as illustrated in FIG. 7. In this exemplary
embodiment a sealing assembly, generally identified by reference
numeral 50, includes an annular sealing element 52 which is bonded
directly to the mandrel 12, and a pair of anchor ring assemblies
10, as described above, are located and anchored to the mandrel 12
at opposing ends of the sealing element 52. The sealing element 52
may be composed of or include a swellable material, such as a
swellable rubber, which swells when contacted by a suitable
activator, such as oil and/or water.
[0119] The anchor ring assemblies 10 may function to provide axial
support to the sealing element 52, for example to assist the
sealing element 52 to resist extrusion, to restrict any axial
swelling and the like. Further, the anchor ring assemblies 10 may
protect the sealing element 52 while the mandrel 12 is run into a
bore.
[0120] In the present embodiment the sealing element 52 may first
be bonded to the mandrel, and the anchor ring assemblies 10 then
located in place. Alternatively, the anchor ring assemblies 10 may
be located on the mandrel and secured in place, with the sealing
element 52 then located and bonded to the mandrel 12.
[0121] An alternative embodiment of a sealing assembly, in this
case generally identified by reference numeral 60, is illustrated
in FIG. 8. The sealing assembly 60 includes a sealing element 62
which is mounted about the mandrel 12. However, in this case the
sealing element 62 is not bonded to the mandrel 12, but instead is
simply slipped over the mandrel 62 and located in the desired
position. A pair of anchor ring assemblies 10, as described above,
are mounted on the mandrel 12 at opposing ends of the sealing
element.
[0122] As in the embodiment shown in FIG. 7, the sealing element 62
in FIG. 8 may include a swellable material. In particular, the
sealing element 62 is composed of a support sleeve 64, which may be
of a metal construction, an outer swellable layer 66 mounted on an
outer surface of the support sleeve 64, and an inner swellable
layer 68 mounted on an inner surface of the support sleeve 64. In
use, the outer layer 66 may swell to provide a seal between the
support sleeve 64 and a bore wall, and the inner layer 68 may swell
to provide a seal between the support sleeve 64 and the mandrel 12.
In some embodiments the sleeve 64 may be perforated such that the
outer and inner swellable layers 66, 68 may be integrated with each
other through the perforations.
[0123] Reference is now made to FIG. 9 which is a cross sectional
view of a portion of an anchor ring assembly, generally identified
by reference numeral 110, in accordance with an alternative
embodiment of the present invention. Anchor ring assembly 110 is
similar to that assembly 10 first shown in FIG. 1 and as such like
features share like reference numerals, incremented by 100.
Accordingly, the assembly 110 includes a housing 114 and a
plurality of slips 116 arranged within a circumferential groove 118
formed in the inner surface of the housing 114. As in the
embodiment first shown in FIG. 1, the slips 116 in the present
embodiment may be extended by use of activator screws (not shown)
to grip a mandrel (also not shown).
[0124] In the present embodiment the housing 114 defines a pair of
circumferential grooves 70, 72 on either side of the slips 116
which are configured to receive respective o-rings 74, 76. These
o-rings 74, 76 permit a seal to be achieved between the housing 114
and a mandrel.
[0125] One end of the housing 114 includes an axial extension 78
which in the present embodiment is for use in engaging an end of a
sealing element 80, which is shown in broken outline. The sealing
element 80 is bonded to the axial extension 78, thus achieving a
seal therebetween.
[0126] In the present embodiment the sealing element 80 defines a
cup sealing element, having a proximal end 82 secured to the axial
extension 78, as described above, and having a distal end (not
illustrated) being free from support, such that a pressure
differential across the sealing element 80 may act to extend the
distal end against a bore wall, to establish and/or increase a seal
therebetween. In this respect, the o-rings 74, 76 function to
prevent leakage of fluid/pressure across the anchor ring assembly
110.
[0127] A perspective view of anchor ring assembly 210 in accordance
with an alternative embodiment of the present invention is shown in
FIG. 1, and a side view of the same assembly 210 is illustrated in
FIG. 2, shown mounted on a mandrel 212 (shown in broken outline).
Anchor ring assembly 210 is similar to assembly 10 first shown in
FIG. 1, and as such like components share like reference numerals,
incremented by 200.
[0128] Accordingly, the anchor ring assembly 210 includes an
annular housing 214 which defines a throughbore 215 to permit the
housing 214 to be mounted on the mandrel 212. The assembly 210
further includes a plurality of slips 216 (ten in this present
embodiment) which are circumferentially arranged within a
circumferential groove 218 formed in an inner surface of the
housing 214. The slips 216 are located between circumferentially
arranged spacer ribs 220 which are secured to the housing via
screws 222. As will be described in more detail below, the ribs 220
function to hold or retain the slips 216 within the housing 214,
while still permitting the slips to be moved radially. As such,
additional retaining features, such as split rings, are not
necessarily required in the present embodiment.
[0129] A plurality of activator members in the form of screws 228
extend from the outer surface of the housing 214 and engage the
rear faces of the respective slips 216, as shown in FIG. 12 which
is a cross sectional view through line 12-12 of FIG. 10. Adjustment
of the activator screws 228 relative to the housing 214 permits the
slips 216 to be extended radially inwardly to grip the outer
surface of the mandrel 212 and thus anchor the assembly 210
thereto.
[0130] In the present embodiment one axial end face 230 of the
housing 214 is generally perpendicular to a central axis of the
housing 214, and an opposite axial end face 232 of the housing 214
defines a tapered surface.
[0131] In a similar manner to the slips 16 of assembly 10, the
slips 216 in the present embodiment define an arcuate inner
surfaces which include a gripping profile in the form of teeth 35.
However, in the present embodiment the teeth are arranged in a
common direction.
[0132] As noted above, the ribs 220 function to retain the slips
216 within the housing. In this respect, reference is now made to
FIG. 13, which is an enlarged view of a portion of the anchor ring
assembly 210 as shown in the section of FIG. 12, with a slip 216a
removed from a pocket 90 defined between two circumferentially
adjacent ribs 220a, 220b. The ribs 220a, 22b are formed and
arranged within the housing 214 to define a radially inner
circumferential separation distance 92 which is smaller than the
radially outer circumferential length 94 of the slip 216a.
Accordingly, once the slip 216a is mounted within the pocket 90,
and the ribs 220a, 220b are securely fastened to the housing 214,
the slip 216a will not be permitted to be removed, yet will be
permitted to move radially within the housing to selectively grip
and release a mandrel 212.
[0133] Reference is now made to FIG. 14 of the drawings in which
there is shown a sealing assembly, generally identified by
reference numeral 300, in accordance with an embodiment of the
present invention. The assembly 300 is adapted to be slipped over a
mandrel (not shown), and located in the desired position, thus
providing a degree of freedom on where and when to apply the
sealing assembly 300.
[0134] The assembly 300 includes a sealing component 302 which
extends between opposing end rings 304, wherein one end ring is
shown removed from the assembly 300 to reveal features of the
sealing component 302. The end rings 304 may function to secure the
entire assembly 300 to a mandrel.
[0135] The sealing component 302 includes a support sleeve 308
which may be of a metal construction and which extends between the
end rings 304. An outer swellable seal layer 310 is mounted on an
outer surface of the support sleeve 308, wherein the outer layer
310 is axially shorter than the support sleeve 308. An inner
swellable seal layer 312 is mounted on an inner surface of the
support sleeve 308, wherein the inner layer 312 is axially longer
than the support sleeve 308. In use, the outer layer 310 may swell
to provide a seal between the support sleeve 308 and a bore wall,
and the inner layer 312 may swell to provide a seal between the
support sleeve 308 and a mandrel, thus achieving a complete annular
seal between the mandrel and bore wall.
[0136] The end rings 304 may be mounted relative to the sealing
component 302 such that an end face 314 of the rings 304 abuts or
engages the outer seal layer 310, whereas an inner surface of the
ends rings 304 engages or abuts the support sleeve 308 and
optionally the inner seal layer 312. In this respect, swelling of
the inner layer 312 may function to establish a seal against the
end rings 304, for example between the end rings 304 and a
mandrel.
[0137] In an alternative embodiment, which is not illustrated, the
support sleeve 308 and outer and inner seal layers 310, 312 may be
of equal axial lengths. In a further alternative embodiment, the
support sleeve 308 may be axially shorter then the inner and outer
seal layers 310, 312. Further, the support sleeve 308 may be
perforated, and the inner and outer seal layers 310, 312 may
engage, for example be integrally formed, through the
perforations.
[0138] Reference is now made to FIG. 15 which illustrates a sealing
assembly, generally identified by reference numeral 320, in
accordance with an alternative embodiment of the present invention,
wherein the sealing assembly 320 is shown mounted on a mandrel 322,
such as an oilfield tubular. In certain embodiments the mandrel 322
may form part of the sealing assembly 320. The mandrel 322 may be
provided in the form of a pup joint. The mandrel 322 may include
threaded connectors 328, 329 at opposing ends thereof. Connector
328 may be a pin type threaded connector, whereas connector 329 may
be a box type threaded connector.
[0139] The sealing assembly 320 includes a swellable seal element
324 which is directly bonded to the outer surface of the mandrel
322. Such bonding may be achieved by use of an adhesive. Such
bonding may be achieved by mounting the swellable material of the
seal element 324 on the mandrel, and then vulcanising the material
to cause the element 324 to become bonded to the mandrel 322.
[0140] The sealing assembly 320 further includes a pair of end
rings 326 mounted at opposite ends of the sealing element 324, and
may be used to protect and axially support the seal element
324.
[0141] It should be understood that the embodiments described
herein are merely exemplary and that various modifications may be
made thereto without departing from the scope of the invention. For
example, the anchor ring assemblies may be for use in other
applications beyond providing support to a sealing element or
component, such as in establishing a no-go on a mandrel. Further,
in some embodiments one, some or all of the ribs (such as ribs 22
or ribs 220) may be integrally formed with the housing.
[0142] The foregoing description is only exemplary of the
principles of the invention. Many modifications and variations of
the present invention are possible in light of the above teachings.
The preferred embodiments of this invention have been disclosed,
however, so that one of ordinary skill in the art would recognize
that certain modifications would come within the scope of this
invention. It is, therefore, to be understood that within the scope
of the appended claims, the invention may be practiced otherwise
than as specifically described. For that reason the following
claims should be studied to determine the true scope and content of
this invention.
* * * * *