U.S. patent application number 12/020095 was filed with the patent office on 2009-07-30 for junction having improved formation collapse resistance and method.
This patent application is currently assigned to BAKER HUGHES INCORPORATED. Invention is credited to Daniel T. Craig, Jobby T. Jacob, Bryan P. Pendleton.
Application Number | 20090188671 12/020095 |
Document ID | / |
Family ID | 40898048 |
Filed Date | 2009-07-30 |
United States Patent
Application |
20090188671 |
Kind Code |
A1 |
Jacob; Jobby T. ; et
al. |
July 30, 2009 |
JUNCTION HAVING IMPROVED FORMATION COLLAPSE RESISTANCE AND
METHOD
Abstract
A junction includes a borehole casing having a window therein; a
diverter disposed within the casing and aligned and oriented with
the window, the diverter having at least one profile along a
longitudinal edge thereof; and a hanger assembly having a window
therein, the window having an edge receivable by the at least one
profile, the profile supporting the hanger assembly and method.
Inventors: |
Jacob; Jobby T.; (Houston,
TX) ; Pendleton; Bryan P.; (Cypress, TX) ;
Craig; Daniel T.; (Fulshear, TX) |
Correspondence
Address: |
CANTOR COLBURN, LLP
20 Church Street, 22nd Floor
Hartford
CT
06103
US
|
Assignee: |
BAKER HUGHES INCORPORATED
HOUSTON
TX
|
Family ID: |
40898048 |
Appl. No.: |
12/020095 |
Filed: |
January 25, 2008 |
Current U.S.
Class: |
166/313 ;
166/242.3 |
Current CPC
Class: |
E21B 41/0035
20130101 |
Class at
Publication: |
166/313 ;
166/242.3 |
International
Class: |
E21B 17/18 20060101
E21B017/18 |
Claims
1. A junction comprising: a diverter having profiled longitudinal
edges; and a hanger assembly configured to engage the profiled
longitudinal edges.
2. The junction as claimed in claim 1 wherein the profiled edges
comprise a radial support surface.
3. The junction as claimed in claim 1 wherein the profiled edges
comprise a hoop support surface.
4. The junction as claimed in claim 1 wherein the profiled edges
each comprise a recess.
5. The junction as claimed in claim 1 wherein the profiled edges
comprise a ramped surface.
6. The junction as claimed in claim 1 wherein the profiled edges
comprise a flat face.
7. The junction as claimed in claim 1 wherein the profiled edges
comprise at least a radial support surface and a hoop support
surface.
8. The junction as claimed in claim 7 wherein the radial and hoop
support surfaces intersect one another.
9. The junction as claimed in claim 8 wherein the intersection is
at an acute angle.
10. The junction as claimed in claim 8 wherein the intersection is
at an obtuse angle.
11. The junction as claimed in claim 9 wherein the acute angle is
about 30 degrees to about 89.9 degrees.
12. A method for improving collapse resistance of a junction
comprising: disposing a diverter having a profiled longitudinal
edge in a borehole at an intersection with a lateral borehole; and
engaging a hanger assembly with the profiled longitudinal edge.
13. A junction comprising: a borehole casing having a window
therein; a diverter disposed within the casing and aligned and
oriented with the window, the diverter having at least one profile
along a longitudinal edge thereof, and a hanger assembly having a
window therein, the window having an edge receivable by the at
least one profile, the profile supporting the hanger assembly.
14. The junction as claimed in claim 13 wherein the supporting is
radial.
15. The junction as claimed in claim 13 wherein the supporting is
in hoop.
Description
BACKGROUND
[0001] In the hydrocarbon recovery industry, multilateral wells
have become more and more used over the last decade or so. In each
case of a lateral borehole extending from a primary borehole or
from another lateral borehole, a natural junction is necessarily
created in the formation. In the vernacular of the hydrocarbon
recovery industry, the term "junction" usually refers to the
man-made part of the well structure that is built into the natural
junction to convey the targeted hydrocarbon to the surface. In some
cases, the junction is intended to be a pressure competent
structure, while in others there is no reason for the junction to
contain pressure. In either type, there is an interest in the
junction to be capable of withstanding formation collapse so that
the well will function for its intended purpose, regardless of the
collapse. Different materials have been used with inherent expense
and thicker materials have been used, again with inherent expense.
While such configurations can be effective in alleviating the
effects of formation collapse to some extent, the added expense is
undesirable and alternate configurations and methods are always
well received by the art.
SUMMARY
[0002] A junction includes a diverter having profiled longitudinal
edges; and a hanger assembly configured to engage the profiled
longitudinal edges.
[0003] A method for improving collapse resistance of a junction
includes disposing a diverter having a profiled longitudinal edge
in a borehole at an intersection with a lateral borehole; and
engaging a hanger assembly with the profiled longitudinal edge.
[0004] A junction includes a borehole casing having a window
therein; a diverter disposed within the casing and aligned and
oriented with the window, the diverter having at least one profile
along a longitudinal edge thereof; and a hanger assembly having a
window therein, the window having an edge receivable by the at
least one profile, the profile supporting the hanger assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Referring now to the drawings wherein like elements are
numbered alike in the several Figures:
[0006] FIG. 1 is a perspective view of a first embodiment of the
junction configuration as disclosed herein;
[0007] FIG. 2 is a cross section view of FIG. 1 taken along section
line 2-2;
[0008] FIG. 3 is a perspective view of a second embodiment of the
junction configuration as disclosed herein;
[0009] FIG. 4 is a cross section view of FIG. 3 taken along section
line 4-4;
[0010] FIG. 5 is a perspective view of a third embodiment of the
junction configuration as disclosed herein;
[0011] FIG. 6 is a cross section view of FIG. 5 taken along section
line 6-6.
DETAILED DESCRIPTION
[0012] Initially, it will be helpful to point out that a part of
the teaching hereof is to provide for support of a hanger assembly
by a seal bore diverter instead of by a casing structure through
which the hanger extends. Such a configuration allows one to take
advantage of the excess strength that exists in the invariably
thicker material of the seal bore diverter. Such support can be
accomplished in several ways, the following embodiments being
representative but not limiting.
[0013] Referring to FIGS. 1 and 2, a junction 10 is illustrated in
perspective view. A casing 12 of a primary bore, whether that
actually is a mother bore to the surface, or another lateral, is
shown with a seal bore diverter 14 therein. One of ordinary skill
in the art will be familiar with a seal bore diverter but not with
the profile illustrated thereon in FIG. 1. The seal bore diverter
14 includes a diverter face 16 bounded on each longitudinal edge
thereof by a recess 18, 20. Each recess as illustrated comprises
two surfaces. One of the surfaces is a radial support surface 22
and the other is a hoop support surface 24. Surfaces 22 and 24
intersect at an acute angle 26 in one embodiment, although it is
possible for the intersection to occur at an obtuse angle with
consequent reduction in hoop support. In the illustration of FIGS.
1 and 2, the angle 26 is about 30 degrees to about 89.9
degrees.
[0014] The surfaces 22 and 24 are dimensioned to approximately the
thickness of a hanger assembly 26, intended to be engaged
therewith. This can be appreciated most easily by viewing FIG. 2.
It is to be understood, however, that it is not required that the
dimensions of surfaces 22 and 24 be exactly the same as a surface
30 of hanger assembly 26 but that the dimensions of surfaces 22 and
24 may be somewhat larger or somewhat smaller than surface 30
without significant change in function of the configuration.
[0015] The dimensions of surfaces 22 and 24 are a product of the
annular dimension of the sealbore diverter 14 at the cross sections
point at which a sectional view is taken. In the FIG. 2 view,
however, it is evident that the dimension of surfaces 22 and 24
provides significant radial support to the hanger assembly 26
relative to what the casing itself might provide simply because of
the much greater surface area available on surfaces 22 and 24.
Prior art arrangements are provided support only by the casing 12
and only by happenstance, as a direct teaching for support of the
junction in such manner is not to be found in the prior art.
[0016] With the arrangement as illustrated in FIGS. 1 and 2, a
significant formation collapse resistance is achieved by providing
both a much greater surface area for radial support and a hoop
support that has not been provided in the past. Crush resistance is
significantly increased both because the hanger assembly 26 cannot
close at its own window due to surfaces 22 and 24 and because a
greater percentage of the hanger assembly 26 is radially supported.
The recesses 18 and 20 may be provided by machining, or may be
molded in, etc.
[0017] In another embodiment, referring to FIGS. 3 and 4, each
longitudinal edge 40 of the seal bore diverter 14, is configured as
a flat face 42, so that hoop stress in the hanger assembly 26 is
supported during the application of formation collapse pressure on
the hanger assembly 26. It is to be appreciated that in this
embodiment, the window 44 in the hanger assembly 26 is milled
differently than is usually the case in the art. Rather, as can be
ascertained from a view of FIG. 4, window edge surfaces 46 are
about ninety degrees from an angle such as that seen in FIGS. 1 and
2. The edges 46 are thus well supported by flat faces 42. This
particular embodiment boasts very easy machining to create but as
will be appreciated by an attentive reader, the hoop strength
improvement of this embodiment is less than that attained in the
embodiment of FIGS. 1 and 2.
[0018] In yet another alternate embodiment, referring to FIGS. 5
and 6, the seal bore diverter 14 is differently configured to have
a scooped ramp 50 on both longitudinal sides of the diverter face
16. In this embodiment, a relatively large surface area of the
hanger assembly 26 is supported by the diverter 14 by each of the
ramps 50. This provides added collapse resistance, by simple
spreading of the load and is otherwise a simple modification to
make to a diverter 14 and thus inexpensive.
[0019] While preferred embodiments have been shown and described,
modifications and substitutions may be made thereto without
departing from the spirit and scope of the invention. Accordingly,
it is to be understood that the present invention has been
described by way of illustrations and not limitation.
* * * * *