U.S. patent application number 12/370401 was filed with the patent office on 2010-08-12 for system for supporting components within a tubular housing of a wellbore.
Invention is credited to Daniel W. Fish, Nicholas P. Gette.
Application Number | 20100200217 12/370401 |
Document ID | / |
Family ID | 42539430 |
Filed Date | 2010-08-12 |
United States Patent
Application |
20100200217 |
Kind Code |
A1 |
Gette; Nicholas P. ; et
al. |
August 12, 2010 |
SYSTEM FOR SUPPORTING COMPONENTS WITHIN A TUBULAR HOUSING OF A
WELLBORE
Abstract
A well system comprising a tubular housing, a hanger assembly,
and a load member disposed in a recess within the central bore of
the housing to support the hanger assembly from the housing. The
recess and the load member are configured so that a greater portion
of the area of the load member extends into the central bore of the
housing as the load member is moved axially in a first direction
within the recess.
Inventors: |
Gette; Nicholas P.;
(Houston, TX) ; Fish; Daniel W.; (Houston,
TX) |
Correspondence
Address: |
Patent Department;GE Oil & Gas
4424 West Sam Houston Parkway North, Suite 100
Houston
TX
77041
US
|
Family ID: |
42539430 |
Appl. No.: |
12/370401 |
Filed: |
February 12, 2009 |
Current U.S.
Class: |
166/86.1 ;
166/208 |
Current CPC
Class: |
E21B 43/10 20130101;
E21B 33/04 20130101 |
Class at
Publication: |
166/86.1 ;
166/208 |
International
Class: |
E21B 33/04 20060101
E21B033/04; E21B 43/10 20060101 E21B043/10; E21B 23/00 20060101
E21B023/00 |
Claims
1. A well system, comprising: a well housing having a hollow
interior comprising a central bore and an annular recess from the
central bore, the recess having a tapered surface; a deformable
ring adapted to be disposed in the recess of the well housing and
extend from within the recess into the central bore, wherein the
ring and the tapered surface of the recess are adapted to compress
the ring as the ring travels axially from a first portion of the
recess to a second portion of the recess to increase ring area
within the central bore.
2. The well system as recited in claim 1, wherein the tapered
surface of the recess is a conical section that decreases in radius
in an axial direction from the first portion of the recess to the
second portion of the recess.
3. The well system as recited in claim 1, wherein the ring has a
tapered surface that faces the tapered surface of the recess.
4. The well system as recited in claim 1, wherein the ring
comprises a surface adapted to support an object from the ring
within the central bore.
5. The well system as recited in claim 4, wherein the surface
adapted to support an object from the ring within the central bore
comprises a seating surface adapted to receive a corresponding
surface of the object.
6. The well system as recited in claim 5, wherein the seating
surface comprises a conical section that decreases in radius in an
axial direction.
7. The well system as recited in claim 1, wherein the well housing
is a high-pressure wellhead.
8. The well system as recited in claim 7, comprising a hanger
assembly, wherein the hanger assembly is supported by the ring
within the high-pressure wellhead.
9. The well system as recited in claim 1, wherein the ring is
biased to expand outward when disposed in the recess in the
housing.
10. A well system, comprising: a well housing having a hollow
interior comprising a central bore and an annular recess from the
central bore; and a collapsible ring disposed within the recess of
the housing and extending from the recess into the central bore to
form a shoulder to support an object disposed within the central
bore, wherein the ring is axially movable within the recess between
a first axial position and a second axial position, the surface
area of the ring within the central bore being greater in the
second axial position than in the first axial position.
11. The well system as recited in claim 10, wherein the recess
comprises an axially-tapered surface.
12. The well system as recited in claim 11, wherein the ring has a
corresponding axially-tapered surface that faces the
axially-tapered surface of the recess.
13. The well system as recited in claim 10, wherein the ring
comprises a seating surface adapted to receive a corresponding
surface of the object.
14. The well system as recited in claim 10, wherein the seating
surface comprises a conical section that decreases in radius in an
axial direction.
15. The well system as recited in claim 10, wherein the well
housing is a high-pressure wellhead.
16. The well system as recited in claim 15, comprising a hanger
assembly, wherein the hanger assembly is supported by the ring
within the high-pressure wellhead.
17. The well system as recited in claim 10, wherein the ring is
biased to expand outward when disposed in the recess in the
housing.
18. A wellhead system, comprising: a well housing having a hollow
interior comprising a central bore and an annular recess from the
central bore, the recess having a tapered surface; a hanger
assembly; and a split ring adapted to be disposed in the recess of
the well housing and extend from within the recess into the central
bore to support the hanger assembly, wherein the tapered surface of
the well housing is configured to collapse the split ring when the
hanger assembly is disposed on the split ring to be supported by
the split ring.
19. The wellhead system as recited in claim 18, wherein the split
ring is disposed in a first axial position in the recess and driven
to a second axial position by the hanger assembly.
20. The wellhead system as recited in claim 19, wherein the area of
the split ring within the central bore is greater when the split
ring is disposed in the second axial position than when the split
ring is disposed in the first axial position.
21. The wellhead system as recited in claim 19, wherein the radius
of the recess is greater in the region corresponding to the first
axial position of the split ring than in the region corresponding
to the second axial position.
22. The wellhead system as recited in claim 18, wherein the split
ring has a tapered surface that faces the tapered surface of the
recess.
23. The wellhead system as recited in claim 18, wherein the split
ring comprises a surface adapted to support the hanger assembly
facing the hanger assembly.
24. The wellhead system as recited in claim 23, wherein the surface
adapted to support the hanger assembly comprises a conical section.
Description
BACKGROUND
[0001] The invention relates generally to a tubular housing used to
support an object within the hollow interior of the tubular
housing. In particular, the invention relates to a system having a
tubular housing, such as a wellhead, to support an assembly, such
as a casing hanger, within the tubular housing via a load member
that extends between the housing and the assembly.
[0002] In the oil and gas industry, pipes and tubing are used to
transport oil and/or gas. In a well, pipe and/or tubing may be
supported by a tubular housing. For example, a wellhead and a
casing hanger disposed within the wellhead may be used to support
pipe, known as casing, within a wellbore. Casing is strong steel
pipe that is used in an oil and gas well to ensure a pressure-tight
connection from the surface to the oil and/or gas reservoir.
However, casing can be used to serve many purposes in a well. For
example, the casing can be used to protect the wellbore from a
cave-in or from being washed out. The casing can also be used to
confine production to the wellbore, so that water does not intrude
into the wellbore from a surrounding formation or so that drilling
mud does intrude into the surrounding formation from the wellbore.
The casing can also provide an anchor for the components of the
well.
[0003] Several sections of casing joined together end-to-end are
known as a "casing string." Because casing serves several different
purposes in a well, it is typical to install more than casing
string in a well. Casing strings typically are run in a concentric
arrangement, similar to an upside-down wedding cake, with each
casing string extending further downward into the ground as the
center of the arrangement of concentric casing strings is
approached. For example, the casing string with the greatest
diameter typically is the outermost casing string and the shortest,
while the casing string with the smallest diameter typically is at
the center and extends the deepest.
[0004] The casing hanger typically supports the casing string from
a wellhead or a similar structure located near the seafloor. The
casing hanger rests on a landing shoulder inside the wellhead.
Multiple casing hangers may supported within a single wellhead.
However, another method that may be used to support a casing
hanger, rather than by using a shoulder of the wellhead, is to use
a load ring to support the casing hanger. The load ring may be
actuated to extend between the casing hanger and a recess in the
wellhead to support the casing hanger.
[0005] Unfortunately, problems may occur when installing components
in the well below the wellhead. The load shoulder needed to support
a casing hanger reduces the diameter of the inner bore of the
wellhead that is available to pass objects through the wellhead.
Thus, the maximum diameter of a well component that that can be
passed through the wellhead is limited by the diameter of the load
shoulder. This limitation affects the maximum diameter of the
casing string that can pass through the wellhead, as well. This, in
turn, reduces the maximum amount of oil and/or gas that can pass
through the casing or production tubing at a given time during the
operation of the well. Various techniques have been developed to
maximize the effective diameter of the inner bore of a wellhead to
enable larger objects to pass through the wellhead for wellheads
having a given diameter. However, these techniques require
complicated mechanisms requiring several components, such as
activation members, load members, etc., to function.
[0006] Therefore, an improved technique for supporting a component
within a tubular housing is desired. The techniques described below
may solve one or more of the problems described above.
BRIEF DESCRIPTION
[0007] A well system comprising a tubular housing, a hanger
assembly, and a load member disposed in a recess within the central
bore of the housing to support the hanger assembly from the
housing. The recess and the load member are configured so that a
greater portion of the area of the load member extends into the
central bore of the housing as the load member is moved axially in
a first direction within the recess.
DRAWINGS
[0008] These and other features, aspects, and advantages of the
present invention will become better understood when the following
detailed description is read with reference to the accompanying
drawings in which like characters represent like parts throughout
the drawings, wherein:
[0009] FIG. 1 is a cross-sectional view of a wellhead system
comprising a casing hanger installed within a high pressure
wellhead, in accordance with an exemplary embodiment of the present
technique;
[0010] FIG. 2 is a detailed cross-sectional view of a portion of
the wellhead system, taken generally along line 2-2 of FIG. 1, in
accordance with an exemplary embodiment of the present
technique;
[0011] FIGS. 3-7 are a series of Figures illustrating the
installation of the casing hanger into the wellhead; in accordance
with an exemplary embodiment of the present technique;
[0012] FIG. 3 is a cross-sectional view illustrating the casing
hanger being lowered into the high pressure wellhead during the
installation process of the casing hanger, in accordance with an
exemplary embodiment of the present technique;
[0013] FIG. 4 is a cross-sectional view illustrating the casing
hanger initially engaging a split ring disposed in a recess within
the high pressure wellhead, in accordance with an exemplary
embodiment of the present technique;
[0014] FIG. 5 is a detailed cross-sectional view of a portion of
the casing hanger, taken generally along line 5-5 of FIG. 4, in
accordance with an exemplary embodiment of the present
technique;
[0015] FIG. 6 is a cross-sectional view illustrating the final
positions of the casing hanger and split ring in the high pressure
wellhead, in accordance with an exemplary embodiment of the present
technique;
[0016] FIG. 7 is a detailed cross-sectional view illustrating the
final positions of the casing hanger and split ring in the high
pressure wellhead, taken generally along line 7-7 of FIG. 6, in
accordance with an exemplary embodiment of the present
technique;
[0017] FIG. 8 is a top view illustrating the initial position of
the split ring relative to the central bore of the high pressure
wellhead, in accordance with an exemplary embodiment of the present
technique; and
[0018] FIG. 9 is a top view illustrating the final position of the
split ring relative to the central bore of the high pressure
wellhead, in accordance with an exemplary embodiment of the present
technique.
DETAILED DESCRIPTION
[0019] Referring now to FIG. 1, the present invention will be
described as it might be applied in conjunction with a technique
for supporting a first device within the hollow interior of a
second device. In the illustrated embodiment, the technique is used
in a wellhead system, as represented generally by reference numeral
20, comprising a high pressure wellhead 22 and a casing hanger
assembly 24. However, the technique may be used in systems other
than a wellhead system. A string of casing (not shown) is connected
to bottom of the casing hanger assembly 24. The casing hanger
assembly 24 and casing string are lowered into a central bore 26 of
the high pressure wellhead 22 by a setting tool (not shown). The
setting tool is supported by a string of pipe extending from a
derrick or crane located on a platform, such as a drilling
ship.
[0020] Referring generally to FIGS. 1 and 2, the casing hanger
assembly 24 is supported in the central bore 26 of the high
pressure wellhead 22 by a load member 28 disposed within a recess
30 from the central bore 26 of the high pressure wellhead 22. The
load member 28 is a contractible ring, such as a C-ring. However,
the load member 28 may be a series of dogs that may be moved inward
into engagement with the casing hanger assembly 24, or some other
type of load bearing assembly.
[0021] In the illustrated embodiment, the recess 30 is configured
to enable the load member 28 to move within the recess 30 along a
longitudinal axis 31 of the wellhead 22. In addition, as will be
discussed in more detail below, the load member 28 and the recess
30 are configured so that a greater portion of the load member 28
is extended from the recess 30 into the central bore 26 of the
wellhead 22 as the load member 28 is moved in a first axial
direction within the recess 30.
[0022] In FIGS. 1 and 2, the load member 28 is shown in a final
position after having moved in the first axial direction from an
initial position above the final position shown here. In the
illustrated embodiment, the recess 30 has a tapered surface 32 and
the load member 28 has a corresponding tapered surface 34 that
faces the tapered surface 32 of the recess 30. The tapered surfaces
32, 34 cooperate to drive the load member 28 inward as the load
member 28 moves axially from the top of the recess 30 to the bottom
in this view. The illustrated embodiment of the recess 30 has a
shoulder 36 that limits axial movement of the load member 28. The
load member 28 has a corresponding surface 38 that is configured to
abut the shoulder 36 of the recess.
[0023] The load member 28 has a surface 40 that is used to form a
shoulder for the casing hanger assembly 24. In the illustrated
embodiment, the surface 40 is tapered. In the illustrated
embodiment, the casing hanger assembly 24 has a protrusion 42 that
engages the load member 28 when the casing hanger assembly 24 is
lowered into the wellhead 22. The protrusion 42 has a surface 44
that faces the surface 40 of the load member 28. In the illustrated
embodiment, the surface 44 is tapered. The tapered surfaces 40, 44
engage in sliding engagement as the casing hanger assembly 24 and
the load member 28 move axially within the wellhead 22.
[0024] A portion of the top surface 40 of the load member 28
extends into the central bore 26 to form a shoulder 46 for
supporting the casing hanger assembly 24 within the central bore
26. As will be discussed in more detail below, the portion of the
surface 40 of the load member 28 that extends into the central bore
26 is greater when the load member 28 is located in the final
position, as shown here in FIGS. 1 and 2, than the portion that
extends into the central bore 26 when the load member 28 is located
in its initial position prior to axial movement within the recess
30. By minimizing the portion of the surface 40 of the load member
28 that extends into the central bore 26 prior to deploying the
casing hanger assembly 24 into the wellhead 22, the diameter
available for an object to be deployed into the wellbore below the
casing hanger 24 is increased.
[0025] Referring generally to FIGS. 3-7, a series of Figures
illustrating the deployment of the casing hanger assembly 24 into
the high pressure wellhead is presented. The casing hanger assembly
24 is initially located above the wellhead 22 in this view. The
casing hanger assembly 24 is then lowered into the high pressure
wellhead to be supported by the load member 28.
[0026] Referring generally to FIG. 3, as noted above, the casing
hanger assembly 24 is lowered into the high pressure wellhead 22 in
a first axial direction, as represented by arrow 48. The load
member 28 is disposed in an upper portion of the recess 30 of the
high-pressure wellhead 22. In the illustrated embodiment, the load
member 28 is outwardly-biased to maintain the load member 28 in the
upper portion of the recess 30. The load member 28 has an opening
50 extending through the load member 28 and having a diameter,
"D1", which is almost as wide in diameter as the full width of the
diameter of the central bore 26 of the wellhead 22. As a result,
objects having a diameter almost as great as the full width
diameter of the central bore 26 of the wellhead 22 may pass through
the load member 28.
[0027] Referring generally to FIGS. 4 and 5, as the casing hanger
assembly 24 is lowered further into the wellhead 22 it eventually
engages the load member 28. With the load member 28 located in the
upper portion of the recess 30, the load member 28 initially
presents a smaller shoulder 52 to the casing hanger assembly 24
than is present after the load member 28 is displaced axially
within the recess 30. Thus, objects having a greater diameter than
the final diameter of the opening 50 through the load member 28 may
be deployed into the wellbore below the casing hanger 24.
[0028] Referring generally to FIGS. 6 and 7, as the casing hanger
assembly 24 is lowered onto the load member 28, it drives the load
member 28 downward within the recess 30 of the wellhead 22 in a
first axial direction, as represented by arrow 54, from the upper
portion of the recess to a lower portion of the recess 30. The
tapered surfaces 32, 34 of the recess 30 and load member 28
cooperate to urge the load member 28 downward and inward, as
represented by arrow 54.
[0029] The inward movement of the load member 28 produced by the
downward axial movement in the recess 30 results in the shoulder 46
presented by the load member 28 after axial movement being greater
in size than the shoulder 52 before axial movement. The top surface
40 of the load member 28 slidingly engages the bottom surface 44 of
the protrusion 42 of the casing hanger assembly 24 as the load
member 28 is driven in the inward direction 56. In addition, the
opening 50 extending through the load member 28 after the inward
movement of the load member 28 has a diameter, "D2", which is
smaller in diameter than the initial diameter, D1. In the
illustrated embodiment, axial movement of the load member is
stopped by the shoulder 36 of the recess 30. In this position, the
load member 28 supports the casing hanger assembly 24 from the high
pressure wellhead 22.
[0030] Referring generally to FIGS. 8 and 9, top views of the load
member 28 extending into the central bore 26 of the high pressure
well head 22 are presented. As best seen in FIG. 8, the illustrated
embodiment of the load member 28 is a split ring that has a gap 56.
The initial shoulder 52 presented by the load member 28 in FIG. 8
extends a lesser distance into the central bore 26 than the final
shoulder 46 presented by the load member in FIG. 9. In addition,
the gap 56 present in FIG. 8 is no longer present in FIG. 9 due to
the inward contraction of the load member 28.
[0031] While only certain features of the invention have been
illustrated and described herein, many modifications and changes
will occur to those skilled in the art. It is, therefore, to be
understood that the appended claims are intended to cover all such
modifications and changes as fall within the true spirit of the
invention.
* * * * *