U.S. patent application number 15/903900 was filed with the patent office on 2018-08-09 for wellhead isolation tool and methods.
This patent application is currently assigned to Oil States Energy Services, L.L.C.. The applicant listed for this patent is Oil States Energy Services, L.L.C.. Invention is credited to Danny L. Artherholt, Charles Beedy, Bob McGuire.
Application Number | 20180223621 15/903900 |
Document ID | / |
Family ID | 63039183 |
Filed Date | 2018-08-09 |
United States Patent
Application |
20180223621 |
Kind Code |
A1 |
McGuire; Bob ; et
al. |
August 9, 2018 |
WELLHEAD ISOLATION TOOL AND METHODS
Abstract
An isolation tool and related methods for protecting a wellhead
to which a casing string is operably coupled. In an exemplary
embodiment, the isolation tool includes an anchor assembly adapted
to be connected to the wellhead; a mandrel adapted to sealingly
engage an interior portion of at least one of the wellhead and the
casing string; and a lock assembly including a mandrel head
connected to the mandrel and adapted to be displaced, relative to
the anchor assembly and the wellhead, to sealingly engage the
mandrel with the interior portion; a landing sleeve connected to
the mandrel head and adapted to be displaced, relative to the
mandrel head, the mandrel, the anchor assembly, and the wellhead,
to engage the anchor assembly; and a connector adapted to secure
the landing sleeve to the anchor assembly when the mandrel
sealingly engages the interior portion and the landing sleeve
engages the anchor assembly. In an alternative embodiment, the
landing sleeve may be unnecessary, as the range of adjustment for
the mandrel may be provided by the combination of a lockdown wing
which threadably engages the anchor assembly and a weight holding
lug which threadably engages the mandrel head.
Inventors: |
McGuire; Bob; (Meridian,
OK) ; Beedy; Charles; (Oklahoma City, OK) ;
Artherholt; Danny L.; (Asher, OK) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Oil States Energy Services, L.L.C. |
Houston |
TX |
US |
|
|
Assignee: |
Oil States Energy Services,
L.L.C.
Houston
TX
|
Family ID: |
63039183 |
Appl. No.: |
15/903900 |
Filed: |
February 23, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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15238019 |
Aug 16, 2016 |
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15903900 |
|
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|
14859702 |
Sep 21, 2015 |
9441441 |
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15238019 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 43/26 20130101;
E21B 19/10 20130101; E21B 33/04 20130101; E21B 17/02 20130101; E21B
33/068 20130101; E21B 33/03 20130101 |
International
Class: |
E21B 33/04 20060101
E21B033/04; E21B 33/068 20060101 E21B033/068; E21B 19/10 20060101
E21B019/10 |
Claims
1. An isolation tool for protecting a wellhead to which a casing
string is operably coupled, the isolation tool comprising: an
anchor assembly comprising a support member, at least a portion of
said support member being externally threaded; a mandrel comprising
a packoff assembly; and a lock assembly comprising: a mandrel head
operably connected to said mandrel, said mandrel comprising an
exterior annular shoulder, and at least a portion of said mandrel
head being externally threaded; a lockdown wing comprising an
interior annular shoulder and an upper annular surface, at least a
portion of said lockdown wing being internally threaded and
configured to threadably engage with the externally threaded
portion of said support member; and a weight holding lug comprising
a lower annular surface configured to abut the upper annular
surface of said lockdown wing, at least a portion of said weight
holding lug being internally threaded and configured to threadably
engage with the externally threaded portion of said mandrel
head.
2. The isolation tool of claim 1, further configured such that said
mandrel and mandrel head are locked in position when said lockdown
wing has threadably engaged said support member.
3. The isolation tool of claim 1, wherein the anchor assembly
further comprises: a first member adapted to be connected to a
wellhead; a base plate connected to the first member and adapted to
be secured to said support member via a weld-less connection.
4. A method of protecting a wellhead to which a casing string is
operably coupled, the method comprising: connecting to a wellhead
an anchor assembly comprising a support member; positioning within
the wellhead a mandrel comprising a packoff assembly, wherein the
mandrel is connected to, and adapted to move axially together with,
a mandrel head; threadably engaging a weight holding lug with an
externally threaded portion of said mandrel head; axially
displacing the mandrel and mandrel head relative to the anchor
assembly and wellhead, such that the packoff assembly is positioned
at a desired location within at least one of the wellhead and the
casing string; threadably engaging a lockdown sleeve with an
externally threaded portion of said support member, such that said
mandrel and mandrel head are locked in the desired position;
rotating said weight holding lug such that the lug advances axially
in a downward direction until a lower annular surface of the weight
holding lug abuts an upper annular surface of said lockdown
wing.
5. The method of claim 4, wherein the desired location of the
packoff assembly creates a sealing engagement with at least one of
the wellhead and the casing string.
6. The method of claim 4, wherein the anchor assembly further
comprises: a first member adapted to be connected to a wellhead; a
base plate connected to the first member and adapted to be secured
to said support member via a weld-less connection.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent
application Ser. No. 15/238,019 filed on Aug. 16, 2016, entitled
WELLHEAD ISOLATION TOOL AND METHODS, which is a continuation of
U.S. patent application Ser. No. 14/859,702, filed on Sep. 21,
2015, now U.S. Pat. No. 9,441,441, issued on Sep. 13, 2016, the
entire disclosures of which are incorporated herein by
reference.
[0002] This application is also related to U.S. patent application
Ser. No. 14/859,665, filed on Sep. 21, 2015, entitled WELLHEAD
ISOLATION TOOL AND METHODS, now U.S. Pat. No. 9,366,103, issued on
Jun. 14, 2016, the entire disclosure of which is incorporated
herein by reference.
TECHNICAL FIELD
[0003] The present disclosure relates generally to oil or gas
wellbore equipment, and, more particularly, to a wellhead isolation
tool and wellsite connectors for same.
BACKGROUND
[0004] Wellhead equipment utilized in connection with an oil or gas
wellbore may be subject to extreme conditions during oilfield
operations, such as, for example, cementing, acidizing, fracturing,
and/or gravel packing of a subterranean wellbore. Wellhead
isolation tools are often used to protect wellhead equipment from
excessive pressures, temperatures, and flow rates encountered
during such oilfield operations. An exemplary wellhead isolation
tool is adapted to position and secure a mandrel within a wellhead.
The mandrel includes a packoff assembly, which is adapted to
isolate the wellhead equipment from fluid flowing through the
mandrel to and from the oil or gas wellbore. However, in the field,
the performance and reliability of the mandrel and packoff assembly
are often an issue because of the extreme duty cycles experienced
by wellhead isolation tools during oilfield operations. For
example, during oil or gas wellbore fracturing operations, wellhead
equipment may be subject to a fluid or slurry pressure of up to
20,000 psi or more. As a result, the high pressures and flow rates
encountered during oil or gas wellbore fracturing operations often
cause packoff assemblies to "lift-off" from a sealing surface,
allowing the fracturing fluid or slurry to leak or blow by the
packoff assembly and into the wellhead equipment. Moreover, in
order to protect the packoff assembly from damage, it is important
to provide support against external forces applied to the mandrel
along the longitudinal axis thereof, in both axial directions.
Therefore, what is needed is an apparatus, system, or method that
addresses one or more of the foregoing issues, among one or more
other issues.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Various embodiments of the present disclosure will be
understood more fully from the detailed description given below and
from the accompanying drawings of various embodiments of the
disclosure. In the drawings, like reference numbers may indicate
identical or functionally similar elements.
[0006] FIG. 1 is a diagrammatic view of a wellhead isolation
assembly, including a hydraulic cylinder, a valve stack, and a
wellhead isolation tool, according to an exemplary embodiment.
[0007] FIG. 2 is an exploded diagrammatic view of the wellhead
isolation tool of FIG. 1, including a lock assembly, an anchor
assembly, and an adapter, according to an exemplary embodiment.
[0008] FIG. 3 is a cross-sectional view of the lock assembly of
FIG. 2, including a mandrel head, a landing sleeve, a threaded wing
nut, and a mandrel, according to an exemplary embodiment.
[0009] FIG. 4 is a cross-sectional view of the anchor assembly of
FIG. 2, including a support member, a base member, and a threaded
wing nut, according to an exemplary embodiment.
[0010] FIG. 5 is a cross-sectional view of the adapter of FIG. 2,
according to an exemplary embodiment.
[0011] FIG. 6A is cross-sectional view of a portion of the wellhead
isolation tool of FIGS. 1-5, the lock assembly of FIG. 3 being
assembled, via a plurality of stay rods, with the anchor assembly
of FIG. 4, according to an exemplary embodiment.
[0012] FIG. 6B is a cross-sectional view of the wellhead isolation
tool of FIGS. 1-5 and 6A, as the lock assembly, anchor assembly,
and stay rods of FIG. 6A are suspended above a wellhead, to which
the adapter of FIG. 5 is connected, according to an exemplary
embodiment.
[0013] FIG. 6C is a cross-sectional view of the wellhead isolation
tool of FIGS. 1-5 and 6A-6B, as the lock assembly, anchor assembly,
and stay rods of FIG. 6A are lowered in relation to the adapter and
wellhead of FIG. 6B, according to an exemplary embodiment.
[0014] FIG. 6D is a cross-sectional view of the wellhead isolation
tool of FIGS. 1-5 and 6A-6C, as the lock assembly is lowered
further in relation to the anchor assembly, the adapter, and the
wellhead, according to an exemplary embodiment.
[0015] FIG. 7 is an enlarged view of a portion of FIG. 6C,
illustrating the anchor assembly connected to, and sealingly
engaged with, the adapter, according to an exemplary
embodiment.
[0016] FIG. 8 is an enlarged view of a portion of FIG. 6D,
illustrating a portion of the mandrel sealed within the wellhead,
according to an exemplary embodiment.
[0017] FIG. 9A is an enlarged view of another portion of FIG. 6D,
illustrating the landing sleeve and threaded wing nut of the lock
assembly in an initial configuration, according to an exemplary
embodiment.
[0018] FIG. 9B is a detailed view of the lock assembly of FIG. 9A,
the landing sleeve being relocated to engage the anchor assembly,
according to an exemplary embodiment.
[0019] FIG. 9C is a detailed view of the lock assembly of FIG. 9B,
the threaded wing nut being threadably connected to the anchor
assembly, according to an exemplary embodiment.
[0020] FIG. 10 is a view of an alternative embodiment in which the
lock assembly does not include a lockdown sleeve but instead
comprises a lockdown wing and weight holding lug, and in which the
anchor assembly comprises an elongated threaded portion used to
provide a range of adjustment for the mandrel.
DETAILED DESCRIPTION
[0021] In an exemplary embodiment, as illustrated in FIG. 1, a
wellhead isolation assembly is schematically illustrated and
generally designated by the reference numeral 10. The wellhead
isolation assembly 10 is adapted to be connected to a wellhead 12,
which is, includes, or is part of, one or more wellhead components,
such as, for example, a casing head 14 and a tubing spool 16. In
several exemplary embodiments, the tubing spool 16 is adapted to
receive a casing string 18, which may include a bit guide 20.
Instead of, or in addition to, the casing head 14 and the tubing
spool 16, the wellhead 12 is, includes, or is part of, one or more
other wellhead components, such as, for example, a casing spool, a
casing hanger, a tubing head, a tubing hanger, a packoff seal, a
valve tree, a blowout preventer, an isolation valve, choke
equipment, another wellhead component, or any combination thereof.
An uppermost flange 22 extends from the wellhead 12.
[0022] Still referring to FIG. 1, the wellhead isolation assembly
10 includes an actuator, such as, for example, a hydraulic cylinder
24. The wellhead isolation assembly 10 also includes a valve stack
26 and a wellhead isolation tool 28. The hydraulic cylinder 24
includes a cylinder barrel 30 and a piston rod 32, which extends
within the cylinder barrel 30. The cylinder barrel 30 defines
opposing end portions 30a and 30b. The end portion 30a of the
cylinder barrel 30 is sealed off by a cylinder cap 34, which
includes a hook connector 36. The end portion 30b of the cylinder
barrel 30 includes a cylinder head 38, through which the piston rod
32 extends. Furthermore, a support plate 40 is connected to the
cylinder barrel 30 at the end portion 30b, and extends radially
outward therefrom.
[0023] The piston rod 32 defines opposing end portions 32a and 32b.
The end portion 32a of the piston rod 32 is connected to a piston
(not shown) disposed within the cylinder barrel 30. The piston (not
shown) is adapted to reciprocate back and forth within the cylinder
barrel 30, thereby causing the piston rod 32 to reciprocate back
and forth through the cylinder head 38. The end portion 32b of the
piston rod 32 includes a plug 42 and a connector, such as, for
example, a threaded wing nut 44. The threaded wing nut 44 is
adapted to connect the plug 42 to the valve stack 26 by threadably
engaging an adapter 46, which is connected to the valve stack 26.
Thus, when the threaded wing nut 44 is connected to the adapter 46,
as shown in FIG. 1, the plug 42 prevents the flow of a fluid
upwardly through the valve stack 26.
[0024] The valve stack 26 includes one or more valves such as, for
example, a pair of valves 48 and 50, which are adapted to either
prevent or allow the flow of a fluid through the valve stack 26.
The valve stack 26 may also include a fluid block 52 connected
between the valves 48 and 50, respectively. The fluid block 52
includes an internal passage (not shown), through which a fluid is
communicated between the valves 48 and 50, respectively. The fluid
block 52 may also include one or more diverter passages (not
shown), through which a fluid is communicated to and/or from the
internal passage of the fluid block 52. The valve stack 26 is
connected to the wellhead isolation tool 28. In several exemplary
embodiments, instead of, or in addition to, the valves 48 and 50,
the valve stack 26 includes one or more other valves.
[0025] The wellhead isolation tool 28 includes a lock assembly 54,
an anchor assembly 56, and an adapter 58. The lock assembly 54 is
adapted to be connected to the anchor assembly 56, as shown in FIG.
1. The anchor assembly 56 includes a base plate 60 that extends
radially outward therefrom. Moreover, as shown in FIG. 1, the
anchor assembly 56 is adapted to be connected to the adapter 58,
which, in turn, is connected to the uppermost flange 22 of the
wellhead 12. In several exemplary embodiments, the adapter 58 is
part of the anchor assembly 56. In several exemplary embodiments,
the adapter 58 is part of the wellhead 12. A plurality of stay rods
62 are connected between the base plate 60 of the anchor assembly
56 and the support plate 40 of the hydraulic cylinder 24. The stay
rods 62 secure the support plate 40 in position relative to the
base plate 60, thereby enabling the hydraulic cylinder 24 to urge
the valves 48 and 50, the fluid block 52, and the lock assembly 54
downwardly toward the anchor assembly 56, as will be discussed in
further detail below.
[0026] Referring to FIG. 2, the wellhead isolation tool 28,
including the lock assembly 54, the anchor assembly 56, and the
adapter 58, is shown in a disassembled state.
[0027] In an exemplary embodiment, as shown in FIG. 2, the lock
assembly 54 includes a mandrel head 64, a landing sleeve 66, and a
connector, such as, for example, a threaded wing nut 68. The lock
assembly 54 is adapted to secure a mandrel 70 in sealing engagement
with at least one of the wellhead 12 and the casing string 18, as
will be discussed in further detail below. In several exemplary
embodiments, the mandrel 70 is part of the lock assembly 54. The
landing sleeve 66 is threadably engaged with the mandrel head 64.
Further, the landing sleeve 66 retains the threaded wing nut 68.
The mandrel head 64 supports a mandrel 70, to which a packoff
assembly 72 is connected. In several exemplary embodiments, the
packoff assembly 72 is part of the mandrel 70. The mandrel 70 is
adapted to extend through the anchor assembly 56 and the adapter
58, and into the wellhead 12. As a result, the packoff assembly 72
is adapted to sealingly engage a portion of at least one of the
wellhead 12 and the casing string 18, as will be discussed in
further detail below.
[0028] In an exemplary embodiment, with continuing reference to
FIG. 2, the anchor assembly 56 includes a support member 74, a base
member 76, and a connector, such as, for example, a threaded wing
nut 78. The base plate 60 is connected to the base member 76 and
extends radially outward therefrom. Further, the base plate 60
includes a plurality of stay rod connectors 80, to which the stay
rods 62 are adapted to be connected. The support member 74 is also
connected to the base member 76 via a flanged connection with the
base plate 60. The support member 74 is adapted to be engaged by,
and threadably connected to, the threaded wing nut 68 of the lock
assembly 54. The base member 76 retains the threaded wing nut 78
for engagement with the adapter 58. The adapter 58 is adapted to be
connected to the uppermost flange 22 of the wellhead 12. The
adapter 58 is thus adapted to be engaged by, and threadably
connected to, the threaded wing nut 78.
[0029] Referring now to FIG. 3, an exemplary embodiment of the lock
assembly 54 of the wellhead isolation tool 28 is illustrated,
including the mandrel head 64, the landing sleeve 66, and the
threaded wing nut 68.
[0030] In an exemplary embodiment, as shown in FIG. 3, the mandrel
head 64 defines opposing end portions 64a and 64b, an interior
portion 64c, and an exterior portion 64d. The mandrel head 64
further defines an internal passage 64e circumscribed by the
interior portion 64c thereof. A flange 82 is connected to the end
portion 64a of the mandrel head 64, and extends radially outward
from the exterior portion 64d thereof. In several exemplary
embodiments, the flange 82 is threadably connected to the end
portion 64a of the mandrel head 64. The flange 82 includes a
plurality of through-holes 84 formed therethrough. The
through-holes 84 accommodate a plurality of fasteners 86, which are
adapted to connect the flange 82 and, consequently, the mandrel
head 64 to the valve 50. An external annular shoulder 88 is formed
into the exterior portion 64d of the mandrel head 64 at the end
portion 64b thereof. The external annular shoulder 88 faces in an
axial direction 90. The mandrel head 64 includes external threads
92 located proximate the end portion 64b thereof, adjacent the
external annular shoulder 88. Further, the mandrel head 64 includes
internal threads 94 located at the end portion 64b thereof. An
internal annular shoulder 96 is formed into the interior portion
64c of the mandrel head 64. The internal annular shoulder 96 faces
in an axial direction 98, which is substantially opposite the axial
direction 90. A pair of annular grooves 100 are formed into the
interior portion 64c of the mandrel head 64, between the internal
threads 94 and the internal annular shoulder 96. The annular
grooves 100 each accommodate an annular seal 102.
[0031] In an exemplary embodiment, with continuing reference to
FIG. 3, the landing sleeve 66 defines opposing end portions 66a and
66b, an interior portion 66c, and an exterior portion 66d. A
plurality of handles 104 are connected to, and extend radially
outward from, the exterior portion 66d of the landing sleeve 66 at
the end portion 66a thereof. The handles 104 are distributed
circumferentially about the landing sleeve 66. An external annular
shoulder 106 is formed into the exterior portion 66c of the landing
sleeve 66 proximate the end portion 66b thereof. The external
annular shoulder 106 faces in the axial direction 90. As a result,
an external annular foot 108 is formed at the end portion 66b of
the landing sleeve 66. An internal annular shoulder 110 is formed
into the interior portion 66c of the landing sleeve 66 proximate
the end portion 66a thereof. The internal annular shoulder 110
faces in the axial direction 98. The landing sleeve 66 includes
internal threads 112 located at the end portion 66a thereof,
adjacent the internal annular shoulder 110. The internal threads
112 of the landing sleeve 66 engage the external threads 92 of the
mandrel head 64. The landing sleeve 66 is adapted to be displaced
relative to the mandrel head 64 in either the axial direction 90 or
the axial direction 98, via the threaded engagement of the internal
threads 112 of the landing sleeve 66 with the external threads 92
of the mandrel head 64. Such axial displacement is accomplished by
rotating the landing sleeve 66 relative to the mandrel head 64, via
the plurality of handles 104. In this manner, the landing sleeve 66
is adapted to be advanced in the axial direction 98 until the
internal annular shoulder 110 of the landing sleeve 66 abuts the
external annular shoulder 88 of the mandrel head 64.
[0032] In an exemplary embodiment, with continuing reference to
FIG. 3, the threaded wing nut 68 defines opposing end portions 68a
and 68b, an interior portion 68c and an exterior portion 68d. An
internal annular shoulder 114 is formed into the interior portion
68c of the threaded wing nut 68 at the end portion 68a thereof. The
internal annular shoulder 114 faces in the axial direction 98. The
threaded wing nut 68 includes internal threads 116 located
proximate the end portion 68b thereof. An internal annular recess
118 is formed in the interior portion 68c of the threaded wing nut
68, between the internal annular shoulder 114 and the internal
threads 116. The internal annular recess 118 is adapted to
accommodate a portion of the external annular foot 108 of the
landing sleeve 66. Further, the threaded wing nut 68 is permitted
to rotate, and slide axially, in relation to the landing sleeve 66,
thus permitting the internal annular shoulder 114 of the threaded
wing nut 68 to abut the external annular shoulder 106 of the
landing sleeve 66.
[0033] In an exemplary embodiment, with continuing reference to
FIG. 3, the mandrel 70 defines opposing end portions 70a and 70b,
an interior portion 70c, and an exterior portion 70d. The mandrel
70 further defines an internal passage 70e circumscribed by the
interior portion 70c thereof. The mandrel 70 includes an end face
120 at the end portion 70a thereof. The end face 120 faces in the
axial direction 90 and abuts the internal annular shoulder 96 of
the mandrel head 64. The mandrel 70 includes external threads 122
located proximate the end portion 70a thereof. The external threads
122 of the mandrel 70 engage the internal threads 94 of the mandrel
head 64, thereby connecting the mandrel 70 to the mandrel head 64.
The exterior portion 70d of the mandrel 70 further defines an
annular sealing surface 124 at the end portion 70a thereof, between
the end face 120 and the external threads 122. Alternatively, in
several exemplary embodiments, the interior portion 64c of the
mandrel head 64 defines the annular sealing surface 124 and the
annular grooves 100 are formed into the exterior portion 70c of the
mandrel 70. In any event, the annular sealing surface 124 is
sealingly engaged by the annular seals 102 accommodated within the
annular grooves 100. In this manner, the annular seals 102 are
adapted to seal a flow of fluid within the internal passages 64e
and 70e, respectively, of the mandrel head 64 and the mandrel 70.
The packoff assembly 72 is connected to the exterior portion 70d of
the mandrel 70 at the end portion 70b thereof. In several exemplary
embodiments, the packoff assembly 72 in integrally formed with the
mandrel 70. The packoff assembly 72 includes an annular body 126
defining opposing end portions 126a and 126b, and an exterior
portion 126c. The exterior portion 126c of the annular body 126
includes an external annular shoulder 128 at the end portion 126b
thereof. The external annular shoulder 128 faces generally in the
axial direction 98. In several exemplary embodiments, the external
annular shoulder 128 is tapered. A plurality of annular grooves 130
are formed in the exterior portion 126c of the annular body 126,
and are axially spaced between the end portions 126a and 126b
thereof. Annular seals 132 are accommodated within respective ones
of the annular grooves 130.
[0034] Referring now to FIG. 4, an exemplary embodiment of the
anchor assembly 56 of the wellhead isolation tool 28 is
illustrated, including the support member 74, the base member 76,
and the threaded wing nut 78.
[0035] In an exemplary embodiment, as shown in FIG. 4, the support
member 74 defines opposing end portions 74a and 74b, an interior
portion 74c, and an exterior portion 74d. The support member 74
further defines an internal passage 74e circumscribed by the
interior portion 74c thereof. The support member 74 includes an end
face 134 at the end portion 74a thereof. The end face 134 faces in
an axial direction 136. The support member 74 includes external
threads 138 at the end portion 74a thereof. The external threads
138 of the support member 74 are adapted to be engaged by, and
connected to, the internal threads 116 of the threaded wing nut 68
of the lock assembly 54. The support member 74 includes an end face
140 at the end portion 74b thereof. The end face 140 faces in an
axial direction 142, which is substantially opposite the axial
direction 136. An axially-facing annular groove 144 is formed into
the end face 140 of the support member 74. The annular groove 144
accommodates a seal 146, such as, for example, a gasket.
[0036] The support member 74 also includes external threads 148 at
the end portion 74b thereof. A flange 150 is connected to the end
portion 74b of the support member 74, via the external threads 148.
Specifically, the flange 150 includes internal threads 152, which
are threadably engaged with the external threads 148 of the support
member 74. The flange 150 also includes a plurality of
through-holes 154 formed therethrough. The through-holes 154 are
adapted to accommodate a plurality of fasteners 156. In several
exemplary embodiments, the threaded engagement of the internal
threads 152 with the external threads 148 enables the connection of
the flange 150 to the support member 74 without the use of metal
joining techniques, such as, for example, welding, brazing, or
soldering. Thus, the connection of the flange 150 to the support
member 74 is a weld-less connection. However, in other embodiments,
the connection of the flange 150 to the support member 74 is
facilitated, at least in part, by a metal joining technique, such
as, for example, welding, brazing, or soldering.
[0037] An internal annular ridge 158 is formed into the interior
portion 74c of the support member 74, proximate the end portion 74a
thereof. Further, an internal annular shoulder 160 is formed into
the interior portion 74c of the support member 74, between the
internal annular ridge 158 and the end face 134. The internal
annular shoulder 160 faces in the axial direction 136. An internal
annular seal, such as, for example, a plurality of self-energizing
annular seals 162, is disposed along the interior portion 74c of
the support member 74, between the internal annular shoulder 160
and the internal annular ridge 158. The self-energizing annular
seals 162 may include any type of self-energizing seals, such as,
for example, O-rings, chevron seals (V-packing), another type of
self-energizing seals, or any combination thereof. Further, a
packing nut 164 is engaged with the internal annular shoulder 160.
The packing nut 164 applies a load, in the axial direction 142,
against the self-energizing annular seals 162 and, consequently,
the internal annular ridge 158. As a result, the self-energizing
annular seals 162 are trapped between the packing nut 164 and the
internal annular ridge 158. Thus trapped, the self-energizing
annular seals 162 are adapted to sealingly engage the exterior
portion 70d of the mandrel 70 when the mandrel 70 extends through
the support member 74. Moreover, once the packing nut 164 is in
place, the self-energizing annular seals 162 are adapted to remain
in a fixed position relative to the anchor assembly 56, including
the support member 74 and the base member 76, during operation of
the lock assembly 54.
[0038] The support member 74 may also include a radially-extending
opening 166 formed therethrough, from the interior portion 74c to
the exterior portion 74d thereof. The radially-extending opening
166 is used to place the support member 74 in fluid communication
with, for example, a variety of bleed-off equipment (not
shown).
[0039] In an exemplary embodiment, with continuing reference to
FIG. 4, the base member 76 defines opposing end portions 76a and
76b, an interior portion 76c, and an exterior portion 76d. The base
member 76 further defines an internal passage 76e circumscribed by
the interior portion 76c thereof. The base member 76 includes an
end face 168 at the end portion 76a thereof. The end face 168 faces
in the axial direction 136. An axially-facing annular groove 170 is
formed into the end face 168 of the base member 76. The annular
groove 170 accommodates the seal 146. Thus, the seal 146 is
disposed within the respective annular grooves 144 and 170 of the
support member 74 and the base member 76. In this position, the
seal 146 is adapted to seal a flow of fluid within the respective
internal passages 74e and 76e of the support member 74 and the base
member 76.
[0040] The base member 76 includes external threads 172 at the end
portion 76a thereof. The base plate 60 is connected to the end
portion 76a of the base member 76, via the external threads 172.
Specifically, the base plate 60 includes internal threads 174,
which are threadably engaged with the external threads 172 of the
base member 76. In several exemplary embodiments, the threaded
engagement of the internal threads 174 with the external threads
172 enables the connection of the base plate 60 to the base member
76 without the use of metal-joining techniques, such as, for
example, welding, brazing, or soldering. Thus, the connection of
the base plate 60 to the base member 76 is a weld-less connection.
However, in other embodiments, the connection of the base plate 60
to the base member 76 is facilitated, at least in part, by a metal
joining technique, such as, for example, welding, brazing, or
soldering. The base plate 60 also includes a plurality of
threaded-holes 176, which are threadably engaged by the plurality
of fasteners 156. Alternatively, in some embodiments, the
threaded-holes 176 are formed into the flange 150 and the
through-holes 154 are formed into the base plate 60. In other
embodiments, the base plate 60 and the flange 150 both include
threaded-holes. In still other embodiments, the flange 150 includes
the through-holes 154 and the base plate 60 also includes
through-holes. In any event, the fasteners 156 connect the flange
150 to the base plate 60 and, consequently, the base member 76. The
connection between the base plate 60 and the flange 150 enables the
connection of the support member 74 to the base member 76 without
the use of metal joining techniques, such as, for example, welding,
brazing, or soldering. Thus, the connection between the base plate
60 and the flange 150 is a weld-less connection. However, in other
embodiments, the connection between the base plate 60 and the
flange 150 is facilitated, at least in part, by a metal joining
technique, such as, for example, welding, brazing, or
soldering.
[0041] An external annular shoulder 178 is formed into the exterior
portion 76d of the base member 76 proximate the end portion 76b
thereof. The external annular shoulder 178 faces in the axial
direction 136. The base member 76 includes an end face 180 at the
end portion 76b thereof. The end face 180 faces in the axial
direction 142. An external annular shoulder 182 is also formed into
the exterior portion 76d of the base member 76 proximate the end
portion 76b thereof, and is located axially between the external
annular shoulder 178 and the end face 180. The external annular
shoulder 182 faces in the axial direction 142. As a result, an
external annular foot 184 is formed at the end portion 76b of the
base member 76. An annular groove 186 is formed into the external
annular shoulder 182. The base member 76 includes an
axially-extending annular portion 188 at the end portion 76b
thereof, extending between the external annular shoulder 182 and
the end face 180. One or more annular grooves 190 are formed into
the annular portion 188 of the base member 76. The annular grooves
190 are each adapted to accommodate an annular seal 192.
[0042] In an exemplary embodiment, with continuing reference to
FIG. 4, the threaded wing nut 78 defines opposing end portions 78a
and 78b, an interior portion 78c and an exterior portion 78d. An
internal annular shoulder 194 is formed into the interior portion
78c of the threaded wing nut 78 at the end portion 78a thereof. The
internal annular shoulder 194 faces in the axial direction 142. The
threaded wing nut 78 includes internal threads 196 located
proximate the end portion 78b thereof. An internal annular recess
198 is formed into the interior portion 78c of the threaded wing
nut 78, between the internal annular shoulder 194 and the internal
threads 196. The internal annular recess 198 is adapted to
accommodate a portion of the external annular foot 184 of the base
member 76. Further, the threaded wing nut 78 is permitted to
rotate, and slide axially, in relation to the base member 76, thus
permitting the internal annular shoulder 194 of the threaded wing
nut 78 to abut the external annular shoulder 178 of the base member
76.
[0043] Referring now to FIG. 5, an exemplary embodiment of the
adapter 58 of the wellhead isolation tool 28 is illustrated. The
adapter 58 defines opposing end portions 58a and 58b, an interior
portion 58c, and an exterior portion 58d. The adapter 58 further
defines an internal passage 58e circumscribed by the interior
portion 58c thereof. The adapter 58 includes an end face 200 at the
end portion 58a thereof. The end face 200 faces in an axial
direction 202. The adapter 58 includes external threads 204 at the
end portion 58a thereof. The external threads 204 of the adapter 58
are adapted to be engaged by, and connected to, the internal
threads 196 of the threaded wing nut 78. A flange 206 is connected
to the end portion 58b of the adapter 58, and extends radially
outward from the exterior portion 58d thereof. The flange 206
includes a plurality of through-holes 208 formed therethrough. The
through-holes 208 accommodate a plurality of fasteners 210, which
are adapted to connect the flange 206 and, consequently, the
adapter 58 to the uppermost flange 22 of the wellhead 12.
[0044] An internal annular shoulder 212 is formed into the interior
portion 58c of the adapter 58 at the end portion 58a thereof. The
internal annular shoulder 212 faces in the axial direction 202. The
adapter 58 includes an axially-extending annular portion 214 at the
end portion 58a thereof, extending between the internal annular
shoulder 212 and the end face 200. The annular portion 214 is
adapted to be sealingly engaged by the annular seals 192, which are
accommodated within the annular grooves 190 in the annular portion
188 of the base member 76. Alternatively, in several exemplary
embodiments, the annular grooves 190 is formed into the annular
portion 214 of the adapter 58 and the annular seals 192 are adapted
to sealingly engage the annular portion 188 of the base member 76.
An annular groove 216 is formed into the end face 200 of the
adapter 58. The annular groove 216 accommodates a resilient metal
seal 218, such as, for example, a metal C-ring seal. The resilient
metal seal 218 is adapted to be crushed between the annular groove
216 in the end face 200 of the adapter 58 and the annular groove
186 in the external annular shoulder 182 of the base member 76. In
this manner, when the base member 76 is connected to the adapter
58, the resilient metal seal 218, along with the annular seals 192,
is adapted to seal a flow of fluid within the respective internal
passages 58e and 76e of the adapter 58 and the base member 76.
[0045] In operation, in an exemplary embodiment, as illustrated in
FIGS. 6A-6D, 7, 8 and 9A-9C, the wellhead isolation tool 28 is used
to fluidically isolate at least a portion of the wellhead 12 from
the casing string 18.
[0046] Referring initially to FIG. 6A, the anchor assembly 56 is
initially assembled with the lock assembly 54, the valve stack 26
(visible in FIG. 1), and the hydraulic cylinder 24 (visible in FIG.
1), such that the mandrel 70 extends through the respective
internal passages 74e and 76e of the support member 74 and the base
member 76. An annular space 220 is thus defined between the
exterior portion 70d of the mandrel 70 and the respective interior
portions 74c and 76c of the support member 74 and the base member
76. Further, the exterior portion 70d of the mandrel 70 is
sealingly, and slidingly, engaged by the self-energizing annular
seals 162 of the support member 74. As mentioned above, the packing
nut 164 retains the self-energizing annular seals 162 in a fixed
position relative to the anchor assembly 56, including the support
member 74 and the base member 76, during operation of the lock
assembly 54. The stay rods 62 are connected between the support
plate 40 of the hydraulic cylinder 24 (visible in FIG. 1) and the
stay rod connectors 80 of the base plate 60. The stay rods 62
secure the support plate 40 in relation to the base plate 60,
thereby enabling the hydraulic cylinder 24 to axially displace the
valve stack 26 and the lock assembly 54 in relation to the anchor
assembly 56.
[0047] Referring now to FIG. 6B, the adapter 58 is shown connected
to the uppermost flange 22 of the wellhead 12 via the flange 206
and the fasteners 210. Regarding the structure of the wellhead 12,
in an exemplary embodiment, the tubing spool 16 of the wellhead 12
defines opposing end portions 16a and 16b, an interior portion 16c,
and an exterior portion 16d. The tubing spool 16 further defines an
internal passage 16e circumscribed by the interior portion 16c
thereof. An internal annular shoulder 222 is formed into the
interior portion 16c of the tubing spool 16. The internal annular
shoulder 222 faces in an axial direction 224. At least one of the
bit guide 20 and the casing string 18 abuts, or nearly abuts, the
internal annular shoulder 222 of the tubing spool 16. An internal
annular shoulder 226 may also be formed into the interior portion
16c of the tubing spool 16. The internal annular shoulder 226 is
located above the internal annular shoulder 222 and faces in an
axial direction 228, which is substantially opposite the axial
direction 224. The tubing spool 16 may also include
radially-extending ports 230 formed therethrough, from the interior
portion 16c to the exterior portion 16d thereof. The
radially-extending ports 230 are used to place the internal passage
16e of the tubing spool 16 in fluid communication with a variety of
well-site equipment (not shown).
[0048] Still referring to FIG. 6B with added reference to FIG. 1,
the hydraulic cylinder 24, the valve stack 26, the lock assembly
54, and the anchor assembly 56, which are secured relative to one
another via the stay rods 62 (as discussed above in relation to
FIG. 6A), are suspended, via the hook connector 36 of the hydraulic
cylinder 24, over the adapter 58 and, consequently, the wellhead
12. From this position, the mandrel 70 and the packoff assembly 72
are ready to be lowered in the axial direction 224, through the
adapter 58, into the wellhead 12, and, consequently, into the
internal passage 16e of the tubing spool 16.
[0049] Referring additionally to FIG. 6C, the hydraulic cylinder
24, the valve stack 26, the lock assembly 54, and the anchor
assembly 56, which are secured relative to one another via the stay
rods 62 (as discussed above in relation to FIG. 6A) and suspended
via the hook connector 36 of the hydraulic cylinder 24 (as
discussed above in relation to FIG. 6B), are lowered in the axial
direction 224 relative to the wellhead 12. As a result, the mandrel
70 and the packoff assembly 72 are inserted through the adapter 58,
into the wellhead 12 and, consequently, into the internal passage
16e of the tubing spool 16. With the mandrel 70 positioned as such,
the self-energizing annular seals 162 of the support member 74
sealingly engage the exterior portion 70d of the mandrel 70.
Further, the interior portion 16c of the tubing spool 16 is engaged
by the annular seals 132 of the packoff assembly 72. Alternatively,
in several exemplary embodiments, the annular seals 132 of the
packoff assembly 72 are adapted to engage an interior portion of
the casing string 18. An annular space 232 is defined between the
exterior portion 70d of the mandrel 70 and the interior portion 58c
of the adapter 58. As the mandrel 70 is lowered in relation to the
wellhead 12, the annular space 232 extends to include additional
annular space defined between the exterior portion 70d of the
mandrel 70 and various components of the wellhead 12, such as, for
example, the uppermost flange 22, the tubing spool 16, etc.
Moreover, the annular space 232 is in fluid communication with the
annular space 220. Accordingly, as the mandrel 70 is lowered, the
self-energizing annular seals 162 of the support member 74 prevent,
or at least obstruct, a flow of fluid through the respective
annular spaces 220 and 232 from escaping to the atmosphere. At the
same time, the self-energizing annular seals 162 remain in a fixed
position relative to the anchor assembly 56, including the support
member 74 and the base member 76.
[0050] Still referring to FIG. 6C, as the hydraulic cylinder 24,
the valve stack 26, the lock assembly 54, and the anchor assembly
56 continue to be lowered in the axial direction 224, the base
member 76 of the anchor assembly 56 is placed into abutment with
the adapter 58. Specifically, as shown in FIG. 7, the end face 180
of the base member 76 abuts, or nearly abuts, the internal annular
shoulder 212 of the adapter 58. In this position, the end face 180
is located axially adjacent the internal annular shoulder 212.
Further, the annular portion 214 of the adapter 58 is sealingly
engaged by the annular seals 192 of the base member 76. Further
still, the external annular shoulder 182 of the base member 76
abuts the end face 200 of the adapter 58. As a result, the
resilient metal seal 218 is crushed between the annular groove 216
in the end face 200 of the adapter 58 and the annular groove 186 in
the external annular shoulder 182 of the base member 76. In this
manner, the resilient metal seal 218, along with the annular seals
192, prevents, or at least obstructs, a flow of fluid within the
respective internal passages 58e and 76e of the adapter 58 and the
base member 76 from escaping to the atmosphere. The base member 76
is secured in relation to the adapter 58 by threadably engaging the
internal threads 196 of the threaded wing nut 78 with the external
threads 204 of the adapter 58, such that the internal shoulder 194
of the threaded wing nut 78 abuts the external annular shoulder 178
of the base member 76. The annular foot 184 of the base member 76
is thus trapped between the internal shoulder 194 of the threaded
wing nut 78 and the end face 200 of the adapter 58. In several
exemplary embodiments, the threaded engagement of the internal
threads 196 with the external threads 204 causes the resilient
metal seal 218 to be crushed between the respective annular grooves
186 and 216 of the base member 76 and the adapter 58.
[0051] Referring now to FIG. 6D, once the base member 76 is secured
to the adapter 58 (as described above in relation to FIGS. 6C and
7), the hydraulic cylinder 24 is actuated to displace the valve
stack 26 and the lock assembly 54 in the axial direction 224,
relative to the anchor assembly 56. As a result, the mandrel 70 is
displaced in the axial direction 224 relative to the anchor
assembly 56, the adapter 58, and the wellhead 12. Moreover, as
shown in FIG. 8, the annular seals 132 of the packoff assembly 72
are displaced in the axial direction 224, relative to the interior
portion 16c of the tubing spool 16, until the external annular
shoulder 128 of the packoff assembly 72 abuts the internal annular
shoulder 226 of the tubing spool 16. In this position, the annular
seals 132 of the packoff assembly 72 are sealingly engaged with the
interior portion 16c of the tubing spool 16, at a location above
the bit guide 20 and the casing string 18. Further, an annular
space 234 is defined between the exterior portion 70d of the
mandrel 70 and the interior portion 16c of the tubing spool 16. The
annular space 234 is in fluid communication with the annular spaces
232 and 220, respectively. In this position, the annular seals 132
of the packoff assembly 72 are operably to prevent, or at least
obstruct, a flow of fluid from the casing string 18 to the annular
spaces 220, 232, and 234, respectively.
[0052] In an exemplary embodiment, as illustrated in FIGS. 9A-9C,
once the external annular shoulder 128 of the packoff assembly 72
has been lowered into abutment with the internal annular shoulder
226 of the tubing spool 16 (as discussed above in relation to FIGS.
6D and 8), the lock assembly 54 is utilized to lock the mandrel 70
and the packoff assembly 72 in position relative to the wellhead
12.
[0053] More particularly, as shown in FIG. 9A, a landing distance
D.sub.1 is initially defined between the external annular foot 108
of the landing sleeve 66 and the end face 134 of the support member
74. Further, a range of adjustment D.sub.2 is defined between the
internal annular shoulder 110 of the landing sleeve 66 and the
external annular shoulder 88 of the mandrel head 64. While
maintaining a sufficient level of hydraulic pressure within the
hydraulic cylinder 24 (visible in FIG. 1) to urge the packoff
assembly 72 into abutment with the internal annular shoulder 226 of
the tubing spool 16, an external force is applied, via the handles
104, in order to rotate the landing sleeve 66. In this manner, the
landing sleeve 66 is threadably advanced in the axial direction 224
and towards the support member 74 until the external annular foot
108 of the landing sleeve 66 abuts the end face 134 of the support
member 74, as shown in FIG. 9B. The engagement of the landing
sleeve 66 with the support member 74 provides support against any
force applied to the lock assembly 54 in the direction 224.
Specifically, any force applied to the mandrel head 64 and/or the
landing sleeve 66 in the direction 224 is borne by the anchor
assembly 56 and, consequently, the adapter 58 and the wellhead 12.
Accordingly, any force applied to the mandrel head 64 and/or the
landing sleeve 66 in the direction 224 is not transferred to the
mandrel 70 or the packoff assembly 72. The lock assembly 54 is thus
capable of protecting the mandrel 70 and the packoff assembly 72 by
supporting the weight of the valve stack 26, the hydraulic cylinder
24, a variety of other wellbore cementing, acidizing, fracturing,
and/or gravel packing equipment, and/or other well-site
equipment.
[0054] Once the external annular foot 108 has been landed on the
support member 74 (as discussed above in relation to FIG. 9B), an
external force is applied to rotate the threaded wing nut 68,
thereby threadably engaging the internal threads 116 of the
threaded wing nut 68 with the external threads 138 of the support
member 74. The threaded wing nut 68 is threadably advanced in the
direction 224 until the internal annular shoulder 114 of the
threaded wing nut 68 abuts the external annular shoulder 106 of the
landing sleeve 66, as shown in FIG. 9C. In this manner, the annular
foot 108 of the landing sleeve 66 is trapped between the internal
annular shoulder 114 of the threaded wing nut 68 and the end face
134 of the support member 74. As a result, the threaded wing nut 68
secures the landing sleeve 66 to the locking member 74, thereby
maintaining the packoff assembly 72 in sealing engagement with the
interior portion 16c of the tubing spool 16. Furthermore, the
engagement of the internal annular shoulder 114 of the threaded
wing nut 68 with the external annular shoulder 106 of the landing
sleeve 66 provides support against any external force applied to
the lock assembly 54 in the direction 202. Specifically, any force
applied to the mandrel head 64 and/or the landing sleeve 66 in the
direction 202 is borne by the anchor assembly 56 and, consequently,
the adapter 58 and the wellhead 12. Accordingly, any force applied
to the mandrel head 64 and/or the landing sleeve 66 in the
direction 202 is not transferred to the mandrel 70 or the packoff
assembly 72. The lock assembly 54 is thus capable of protecting the
mandrel 70 and the packoff assembly 72 from any force in the
direction 202 that may cause leakage, blow by, and/or "lift-off" of
the packoff assembly, such as, for example, excessive fluid
pressure within the casing string 18, the tubing head 16, and/or
the mandrel 70.
[0055] In order for the external annular foot 108 to properly land
on the end face 134 of the support member 74, the landing distance
D.sub.1 must be less than, or equal to, the range of adjustment
D.sub.2. In several exemplary embodiments, in order to ensure that
the landing distance D.sub.1 is less than, or equal to, the range
of adjustment D.sub.2, the overall length of the mandrel 70 is
adjusted via the addition or removal of one or more mandrel
extension sections (not shown). Accordingly, the lock assembly 54
is compatible for use with a variety of different wellheads,
including, but not limited to, the wellhead 12.
[0056] Once the landing sleeve 66 has been secured to the locking
member 74 via the threaded wing nut 68 (as discussed above in
relation to FIG. 9C), the stay rods 62 and hydraulic cylinder 24
are removed from the wellhead isolation assembly 10 so that the
valve stack 26 and the wellhead isolation tool 28 may be used to
conduct one or more oil or gas wellbore operations, such as, for
example, cementing, acidizing, fracturing, and/or gravel packing of
a subterranean wellbore. In several exemplary embodiments, use of
the wellhead isolation tool 28 as described herein in connection
with the above-described wellbore operations prevents, or at least
reduces, any tendency of the packoff assembly 72, including the
annular seals 132, to "lift-off" from the internal annular shoulder
226 and/or the interior portion 16c of the tubing spool 16. In this
manner, the wellhead isolation tool 28 prevents the operating fluid
from leaking or blowing by the packoff assembly 72, including the
annular seals 132, and into the wellhead 12. In several exemplary
embodiments, use of the wellhead isolation tool 28 as described
herein protects the packoff assembly 72, including the annular
seals 132, from damage by supporting against external forces
applied to the mandrel 70 along the longitudinal axis thereof, in
both of the axial directions 202 and 224, respectively.
[0057] In several exemplary embodiments, the lock assembly 54
operates to prevent, or at least reduce, the transfer of any force
from the mandrel head 64 or the landing sleeve 66 to the mandrel 70
and, consequently, the packoff assembly 72.
[0058] In several exemplary embodiments, the lock assembly 54
operates to prevent, or at least reduce, the transfer of any axial
force from the mandrel head 64 or the landing sleeve 66 to the
mandrel 70 and, consequently, the packoff assembly 72.
[0059] In several exemplary embodiments, the lock assembly 54
isolates the mandrel 70 and the packoff assembly 72 from any
external forces that are applied to the mandrel head 64 or the
locking sleeve 66.
[0060] In several exemplary embodiments, the lock assembly 54
operates to lock the mandrel 70, including the packoff assembly 72,
down into position within the wellhead 12, while, at the same time,
supporting the weight of the valve stack 26, the hydraulic cylinder
24, a variety of other wellbore fracturing and gravel packing
equipment, and/or other well-site equipment.
[0061] The anchor assembly 56 and the adapter 58 have been
described herein as part of the wellhead isolation assembly 10.
However, in several exemplary embodiments, instead of, or in
addition to, being part of the wellhead isolation assembly 10, the
anchor assembly 56 is, includes, or is part of, a wellsite
connector that may be used to connect various wellsite components
within a number of wellsite systems, such as, for example, a pump
system, a manifold system, a lubricator system, another wellsite
system, etc. Further, in several exemplary embodiments, instead of,
or in addition to, being part of the wellhead isolation assembly
10, the combination of the anchor assembly 56 and the adapter 58
is, includes, or is part of, another wellsite connector that may be
used to connect various wellsite components within a number of
wellsite systems, such as, for example, a pump system, a manifold
system, a lubricator system, another wellsite system, etc. Further
still, in several exemplary embodiments, instead of, or in addition
to, being part of the wellhead isolation assembly 10, the
combination of the base member 76 and the adapter 58 is, includes,
or is part of, yet another wellsite connector that may be used to
connect various wellsite components within a number of wellsite
systems, such as, for example, a pump system, a manifold system, a
lubricator system, another wellsite system, etc.
[0062] Moreover, in several exemplary embodiments, instead of, or
in addition to, being part of the wellhead isolation assembly 10,
one or more components of the anchor assembly 56 form, include, or
are part of, a wellsite connector that may be used to connect
various wellsite components within a number of wellsite systems,
such as, for example, a pump system, a manifold system, a
lubricator system, another wellsite system, etc. Further, in
several exemplary embodiments, instead of, or in addition to, being
part of the wellhead isolation assembly 10, the combination of one
or more components of the anchor assembly 56 and one or more
components of the adapter 58 is, includes, or is part of, another
wellsite connector that may be used to connect various wellsite
components within a number of wellsite systems, such as, for
example, a pump system, a manifold system, a lubricator system,
another wellsite system, etc. Further still, in several exemplary
embodiments, instead of, or in addition to, being part of the
wellhead isolation assembly 10, the combination of one or more
components of the base member 76 and one or more components of the
adapter 58 is, includes, or is part of, yet another wellsite
connector that may be used to connect various wellsite components
within a number of wellsite systems, such as, for example, a pump
system, a manifold system, a lubricator system, another wellsite
system, etc.
[0063] In several exemplary embodiments, as illustrated in FIGS.
1-7 and 9A-9C, each of the fasteners 86, 156, and 210 includes a
threaded stud and a nut threadably engaged therewith. In several
exemplary embodiments, instead of a threaded stud and a nut
threadably engaged therewith, one or more of the fasteners 86, 156,
and 210 includes a bolt, the bolt including a bolt head and an
axial portion extending therefrom and through a corresponding one
of the through-holes 84, 154, or 208, at least the distal end
portion of the axial portion including external threads that
threadably engage corresponding internal threads of the valve 50,
corresponding ones of the threaded-holes 176, or corresponding
internal threads formed in the uppermost flange 22 of the wellhead
12. In several exemplary embodiments, one or more of the
through-holes 84, 154, and 208 are threaded-holes which, in several
exemplary embodiments, may be threadably engaged with corresponding
ones of the fasteners 86, 156, and 210, respectively. In several
exemplary embodiments, the threaded-holes 176 are through-holes,
each of which extends through the base plate 60. In several
exemplary embodiments, the threaded-holes 176 are through-holes,
each of which extends through the base plate 60, and each of the
fasteners 156 extends through the flange 150 and the base plate 60.
In several exemplary embodiments, the threaded-holes 176 are
through-holes, each of which extends through the base plate 60, and
each of the fasteners 156 extends through the flange 150 and the
base plate 60, and each of the fasteners 156 further includes
another nut that is threadably engaged with the threaded stud and
that engages the flange 150 on the side thereof axially opposing
the flange 150. In several exemplary embodiments, instead of, or in
addition to, a threaded stud and a nut threadably engaged
therewith, one or more of the fasteners 86, 156, and 210 includes
one or more other components such as, for example, another nut
threadably engaged with the threaded stud.
[0064] Referring now to FIG. 10, an alternative embodiment is
disclosed. In this embodiment, lock assembly 254 includes a mandrel
head 264 similar to mandrel head 64 in the previously described
embodiments. In particular, mandrel head 264 includes exterior
annular shoulder 298 similar to shoulder 88 in the prior
embodiments. Mandrel head 264 also comprises external threads 284.
Mandrel head 264 is connected to a mandrel comprising a packoff
assembly, substantially similar to the prior disclosed embodiments.
The embodiment of FIG. 10, however, does not include a landing
sleeve, as do the other disclosed embodiments. Instead, lock
assembly 254 comprises lockdown wing 268 and weight holding lug
288. In addition, support member 274 includes a threaded portion
238 that is elongated, as compared to support member 74 of the
other embodiments. In other respects, the anchor assembly of this
alternative embodiment may be similar to anchor assembly 56 shown
in other embodiments of the invention.
[0065] Lockdown wing 268 comprises internal annular shoulder 310,
which engages exterior annular shoulder 298 of mandrel head 264.
Lockdown wing 268 also comprises internal threads 316 which engage
with external threads 238 on support member 274, as described in
more detail below. Lockdown wing 268 also comprises an upper
annular surface 314, which extends radially outward from the
central longitudinal axis of the tool.
[0066] Weight holding lug 288 comprises a lower annular surface
312, which extends radially outward from the central longitudinal
axis of the tool. When the isolation tool of this embodiment is
installed and fully engaged, lower annular surface 312 of weight
holding lug 288 abuts upper annular surface 314 of lockdown wing
268, as shown in FIG. 10. Weight holding lug 288 also comprises
internal threads 308 which engage with external threads 284 on
mandrel head 264, as described in more detail below.
[0067] To install the embodiment shown in FIG. 10, the mandrel is
moved axially downward into position such that the packoff assembly
is in the desired location, as described above in connection with
FIG. 8. During this step of the installation process, weight
holding lug 288 is engaged with mandrel head 264 through the
interaction of internal threads 308 and external threads 284. This
engagement supports the weight of the tool, which avoids putting
substantial downward axial pressure on the bit guide during
installation.
[0068] Once the packoff assembly is in the desired position,
lockdown wing 268 is threadably advanced in an axial direction,
through the engagement of internal threads 316 and external threads
238 on support member 274, until internal annular shoulder 310
abuts exterior annular shoulder 298 of mandrel head 264. At this
point, the mandrel and packoff assembly are locked in position and
mandrel head 264 is just above support member 274. Finally, weight
holding lug 288 is threadably advanced in an axial direction,
through engagement of internal threads 308 and external threads
284, until lower annular surface 312 of weight holding lug 288
abuts upper annular surface 314 of lockdown wing 268.
[0069] The present disclosure introduces a wellsite connector
apparatus, including an adapter including a first end face having a
first annular groove formed therein, a first annular shoulder, and
a first annular portion extending axially between the first end
face and the first annular shoulder; a first member adapted to be
connected to the adapter, the first member including a second end
face, a second annular shoulder having a second annular groove
formed therein, and a second annular portion extending axially
between the second end face and the second annular shoulder; and a
resilient metal seal adapted to be crushed between the first and
second annular grooves when the first member is connected to the
adapter; wherein, when the first member is connected to the
adapter, the first end face and the first annular shoulder are
axially adjacent the second end face and the second annular
shoulder, respectively, and the first and second annular portions
are radially adjacent one another. In an exemplary embodiment, one
of the first and second annular portions includes one or more
annular grooves and the other of the first and second annular
portions includes an annular sealing surface; wherein the wellsite
connector apparatus further comprises one or more annular seals
extending within the one or more annular grooves, respectively;
and, when the first and second annular portions are radially
adjacent one another, the one or more annular seals sealingly
engage the annular sealing surface. In an exemplary embodiment, the
resilient metal seal is a metal C-ring seal. In an exemplary
embodiment, the wellsite connector apparatus further includes a
connector including internal threads and an internal annular
shoulder; wherein one of the adapter and the first member includes
external threads and the other of the adapter and the first member
includes an external annular shoulder; wherein, when the first
member is connected to the adapter, the internal threads of the
connector threadably engage the external threads so that the
internal annular shoulder of the connector engages the external
annular shoulder to crush the resilient metal seal between the
first and second annular grooves. In an exemplary embodiment, the
wellsite connector apparatus further includes a base plate
connected to the first member via a first weld-less connection and
a flange connected to a second member via a second weld-less
connection, the base plate and the flange being connected to each
other via a third weld-less connection; wherein the first and
second members define first and second fluid passageways,
respectively; and wherein the first, second, and third weld-less
connections are configured so that the first and second fluid
passageways are in fluid communication with each other. In an
exemplary embodiment, the first member includes first external
threads and the base plate includes first internal threads that are
threadably engaged with the first external threads to effect the
first weld-less connection; and the second member defines second
external threads and the flange defines second internal threads
that are threadably engaged with the second external threads to
effect the second weld-less connection. In an exemplary embodiment,
a plurality of threaded-holes are formed in one of the base plate
and the flange and distributed circumferentially thereabout; a
plurality of through-holes are formed through the other of the base
plate and the flange and distributed circumferentially thereabout,
the through-holes being aligned with the threaded-holes; and a
plurality of fasteners extend through the through-holes and
threadably engage the threaded-holes to effect the third weld-less
connection.
[0070] The present disclosure also introduces a wellsite connector
apparatus, including first and second members defining first and
second fluid passageways, respectively, the first and second
members being adapted to be connected to first and second wellsite
components, respectively; a base plate connected to the first
member via a first weld-less connection; and a flange connected to
the second member via a second weld-less connection; wherein the
base plate and the flange are connected to each other via a third
weld-less connection; and wherein the first, second, and third
weld-less connections are configured so that: the first and second
fluid passageways are co-axial; and the first and second wellsite
components are in fluid communication with each other, via at least
the first and second fluid passageways, when the first and second
members are connected to the first and second wellsite components,
respectively. In an exemplary embodiment, the first member includes
first external threads and the base plate includes first internal
threads that are threadably engaged with the first external threads
to effect the first weld-less connection; and the second member
defines second external threads and the flange defines second
internal threads that are threadably engaged with the second
external threads to effect the second weld-less connection. In an
exemplary embodiment, a plurality of threaded-holes are formed in
one of the base plate and the flange and distributed
circumferentially thereabout; a plurality of through-holes are
formed through the other of the base plate and the flange and
distributed circumferentially thereabout, the through-holes being
aligned with the threaded-holes; and a plurality of fasteners
extend through the through-holes and threadably engage the
threaded-holes to effect the third weld-less connection. In an
exemplary embodiment, the first member includes a first annular
shoulder having a first annular groove formed therein; and the
wellsite connector apparatus further includes an adapter to which
the first wellsite component is adapted to be connected, the
adapter being connected to the first member and comprising a first
end face having a second annular groove formed therein; and a
resilient metal seal crushed between the first and second annular
grooves. In an exemplary embodiment, the wellsite connector
apparatus further includes a connector including internal threads
and an internal annular shoulder; wherein one of the adapter and
the first member includes external threads and the other of the
adapter and the first member includes an external annular shoulder;
and wherein the internal threads of the connector threadably engage
the external threads and the internal annular shoulder of the
connector engages the external annular shoulder so that the
resilient metal seal is crushed between the first and second
annular grooves. In an exemplary embodiment, the first member
further includes a second end face and a first annular portion
extending axially between the second end face and the first annular
shoulder; the adapter further includes a second annular shoulder
and a second annular portion extending axially between the first
end face and the second annular shoulder; and the first and second
annular portions are radially adjacent one another. In an exemplary
embodiment, one of the first and second annular portions includes
one or more annular grooves and the other of the first and second
annular portions includes an annular sealing surface; the wellsite
connector apparatus further includes one or more annular seals
extending within the one or more annular grooves, respectively;
and, when the first and second annular portions are radially
adjacent one another, the one or more annular seals sealingly
engage the annular sealing surface.
[0071] The present disclosure also introduces a method of
assembling a wellsite connector apparatus, the method including
connecting a base plate to a first member via a first weld-less
connection, the first member defining a first fluid passageway and
being adapted to be connected to a first wellsite component;
connecting a flange to a second member via a second weld-less
connection, the second member defining a second fluid passageway
and being adapted to be connected to a second wellsite component;
and connecting the flange to the base plate via a third weld-less
connection; wherein the first, second, and third weld-less
connections are configured so that: the first and second fluid
passageways are co-axial; and the first and second wellsite
components are in fluid communication with each other, via at least
the first and second fluid passageways, when the first and second
members are connected to the first and second wellsite components,
respectively. In an exemplary embodiment, connecting the base plate
to the first member via the first weld-less connection includes
threadably engaging first internal threads of the base plate with
first external threads of the first member; and connecting the
flange to the second member via the second weld-less connection
includes threadably engaging second internal threads of the flange
with second external threads of the second member. In an exemplary
embodiment, a plurality of threaded-holes are formed in one of the
base plate and the flange and distributed circumferentially
thereabout; a plurality of through-holes are formed through the
other of the base plate and the flange and distributed
circumferentially thereabout; and connecting the flange to the base
plate via the third weld-less connection includes threadably
engaging a plurality of fasteners with respective ones of the
threaded-holes, aligning the through-holes with the threaded-holes,
and inserting the plurality of fasteners through respective ones of
the through-holes. In an exemplary embodiment, the first member
includes a first annular shoulder having a first annular groove
formed therein; and the method further includes: providing an
adapter comprising a first end face having a second annular groove
formed therein; and connecting the first member to the adapter so
that a resilient metal seal is crushed between the first and second
annular grooves. In an exemplary embodiment, connecting the first
member to the adapter includes threadably engaging internal threads
of a connector with external threads of one of the adapter and the
first member; and engaging an internal annular shoulder of the
connector with an external annular shoulder of the other of the
adapter and the first member to crush the resilient metal seal
between the first and second annular grooves. In an exemplary
embodiment, the first member further includes a second end face and
a first annular portion extending axially between the second end
face and the first annular shoulder; the adapter further includes a
second annular shoulder and a second annular portion extending
axially between the first end face and the second annular shoulder;
and, when the first member is connected to the adapter, the first
end face and the first annular shoulder are axially adjacent the
second end face and the second annular shoulder, respectively, and
the first and second annular portions are radially adjacent one
another.
[0072] It is understood that variations may be made in the
foregoing without departing from the scope of the present
disclosure.
[0073] In several exemplary embodiments, the elements and teachings
of the various illustrative exemplary embodiments may be combined
in whole or in part in some or all of the illustrative exemplary
embodiments. In addition, one or more of the elements and teachings
of the various illustrative exemplary embodiments may be omitted,
at least in part, and/or combined, at least in part, with one or
more of the other elements and teachings of the various
illustrative embodiments.
[0074] Any spatial references, such as, for example, "upper,"
"lower," "above," "below," "between," "bottom," "vertical,"
"horizontal," "angular," "upwards," "downwards," "side-to-side,"
"left-to-right," "right-to-left," "top-to-bottom," "bottom-to-top,"
"top," "bottom," "bottom-up," "top-down," etc., are for the purpose
of illustration only and do not limit the specific orientation or
location of the structure described above.
[0075] In several exemplary embodiments, while different steps,
processes, and procedures are described as appearing as distinct
acts, one or more of the steps, one or more of the processes,
and/or one or more of the procedures may also be performed in
different orders, simultaneously and/or sequentially. In several
exemplary embodiments, the steps, processes, and/or procedures may
be merged into one or more steps, processes and/or procedures.
[0076] In several exemplary embodiments, one or more of the
operational steps in each embodiment may be omitted. Moreover, in
some instances, some features of the present disclosure may be
employed without a corresponding use of the other features.
Moreover, one or more of the above-described embodiments and/or
variations may be combined in whole or in part with any one or more
of the other above-described embodiments and/or variations.
[0077] Although several exemplary embodiments have been described
in detail above, the embodiments described are exemplary only and
are not limiting, and those skilled in the art will readily
appreciate that many other modifications, changes and/or
substitutions are possible in the exemplary embodiments without
materially departing from the novel teachings and advantages of the
present disclosure. Accordingly, all such modifications, changes,
and/or substitutions are intended to be included within the scope
of this disclosure as defined in the following claims. In the
claims, any means-plus-function clauses are intended to cover the
structures described herein as performing the recited function and
not only structural equivalents, but also equivalent structures.
Moreover, it is the express intention of the applicant not to
invoke 35 U.S.C . . . sctn.112, paragraph 6 for any limitations of
any of the claims herein, except for those in which the claim
expressly uses the word "means" together with an associated
function.
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