U.S. patent application number 10/041974 was filed with the patent office on 2003-07-10 for modular liner hanger.
This patent application is currently assigned to Weatherford International, Inc.. Invention is credited to Marcin, Jozeph Robert, Wilkin, James Frederick.
Application Number | 20030127222 10/041974 |
Document ID | / |
Family ID | 21919355 |
Filed Date | 2003-07-10 |
United States Patent
Application |
20030127222 |
Kind Code |
A1 |
Marcin, Jozeph Robert ; et
al. |
July 10, 2003 |
Modular liner hanger
Abstract
A liner hanger having a mechanical coupling between a liner
hanger body and one or more cones is disclosed. The cones are
coupled to the liner hanger body to resist axial and relative
rotational movement without welding the cones to the hanger body,
and without the need to use integral cones. In general, the
mechanical coupling includes a hanger body or casing mandrel, a
cone assembly journaled on the casing mandrel, at least one slot or
groove in an outer wall of the casing mandrel, and at least one
partially or fully annular slot on the inside surface of the cone
assembly oriented to correspond with the groove(s) in the outer
wall of the hanger body. At least one wire, or one or more
bearings, is situated in the corresponding slot and the groove. The
wire engages the flanks of the slot and groove sufficiently to
resist axial or rotational movement of the cones relative to the
hanger body.
Inventors: |
Marcin, Jozeph Robert; (St.
Albert, CA) ; Wilkin, James Frederick; (US) |
Correspondence
Address: |
John R. Keville
HOWREY SIMON ARNOLD & WHITE LLP
750 Bering Drive
Houston
TX
77057
US
|
Assignee: |
Weatherford International,
Inc.
|
Family ID: |
21919355 |
Appl. No.: |
10/041974 |
Filed: |
January 7, 2002 |
Current U.S.
Class: |
166/208 ;
166/217 |
Current CPC
Class: |
Y10T 403/75 20150115;
Y10T 403/41 20150115; Y10T 403/62 20150115; Y10T 403/7073 20150115;
E21B 43/10 20130101 |
Class at
Publication: |
166/208 ;
166/217 |
International
Class: |
E21B 023/02 |
Claims
What is claimed is:
1. A liner hanger comprising: a casing mandrel; a cone assembly
journaled on the casing mandrel; a slot on an outer wall of the
casing mandrel; a groove, at least partially annular, on an inside
surface of the cone assembly oriented with the slot; at least one
wire situated in the slot and the groove.
2. The tool assembly of claim 1 wherein there are a plurality of
slots, and a plurality of grooves oriented with the slots.
3. The tool assembly of claim 2 wherein there is a single helical
slot oriented with a single helical groove.
4. A mechanical coupling between a liner hanger body and one or
more cones, the coupling comprising: at least one indent in the
liner hanger body outer wall; at least one indent in an inner
surface of the cones; and a plurality of bearings at least
partially located in the indent in the liner hanger body outer wall
and at least partially in the indent in the inner surface of the
cones to resist axial movement of the cones relative to the liner
hanger body.
5. A mechanical coupling between a liner hanger body and one or
more cones, the coupling comprising: at least one indent in the
liner hanger body outer wall; at least one indent in an inner
surface of the cones; and a wire radially located in the indent in
the liner hanger body outer wall and in the indent in the inner
surface of the cones to resist axial movement of the cones relative
to the liner hanger body.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to setting liner hangers
during well completion or maintenance operations. In particular,
the invention is directed to a liner hanger in which the cones of
the liner hanger are non-integral to the barrel and attached by
mechanical means without welding.
[0002] Generally, in a producing well, casing (lengths of steel
pipe joined together) runs from the surface to a specified depth in
the wellbore. The casing generally has a large diameter. It is
installed and cemented in place to seal off drilling and
circulating fluids from the borehole and prevent commingling of
well fluids, and to prevent the walls of the borehole from caving.
The casing string is generally hung from a hanger on the
surface.
[0003] A liner is a length of casing that is hung inside existing
casing. Unlike the casing string, the liner generally does not
extend to the surface, but is anchored, suspended, and supported by
a liner hanger that is installed near the bottom of the casing in
which the liner is suspended, or near the location where the liner
string is desired to isolate problems such as from other zones such
as lost circulation or high pressure. The liner also provides
capital savings in reducing the cost of the steel pipe needed since
it does not run to the top of the well.
[0004] A liner hanger holds the liner in place once the liner is in
the desired location in the well, and carries the weight of the
liner after it is hung off. Mechanical or hydraulic slips on the
hanger hold the liner in place by gripping the inside wall of the
casing in which the liner is suspended. Hangers may be set
hydraulically by creating pressure in the hanger, activating
hydraulic pistons that move the slips against the casing. During
the running process the slips are retained in a retracted position.
Once the liner is in the desired position, the slips are driven
across the cones by the activation mechanism, which may be
mechanical or hydraulic, thereby increasing the diameter of the
slips and forcing the teeth on the outer surface into the casing.
Liner hangers generally include one or more sets of cones and
slips.
[0005] The cones are wedge-shaped sections on the liner hanger's
outer wall. Generally in the past, the cones have been integral to
the barrel of the liner hanger. For example, in a common type of
prior art liner hanger the barrel is made of two piece
construction, as shown in FIGS. 1A and 1B. A lower portion of the
barrel is threaded onto an upper portion and acts as a hydraulic
cylinder. The entire assembly contains a longitudinal throughbore
that allows for the passage of fluids during the running process.
The slips and cones are slotted to allow the passage of fluid in
the annulus around the liner hanger during the running in/removal
or cementing processes.
[0006] With the hydraulic version, when the liner hanger is in the
desired position, the operator creates an increased pressure,
generally by dropping a ball or dart into a ball seat or other
receptacle in a landing collar below the liner hanger. At a
particular increased pressure a setting piston moves upward to an
extended position. The setting piston drives a setting sleeve,
connected by one or more slip arms to the slips. This drives the
slips, which expand out over the wedge-shaped cone pads until fully
gripping the inside of the casing. Downward motion transfers the
full liner weight through the cones and slips into the supporting
casing.
[0007] Alternatively, the hanger can be mechanically set. In one
such hanger, the work string attached to the liner hanger is
rotated. Rotation may be right-hand set or left hand set depending
on the desired embodiment. The rotation causes a J-Cage mechanism
in contact with the casing to disengage a lug from the short leg of
the J-Cage and allows the slips to align with the cones. Downward
motion then allows the slips to expand over the cones and grip the
casing's inner wall, transferring the weight of the liner to the
supporting casing.
[0008] A disadvantage of such prior art liner hangers is that they
must be constructed using a very thick-walled steel tube stock, for
example a six inch inner diameter might require an eight inch outer
diameter, in order for the wall to have sufficient thickness in the
area of the cones and the cylinder once the steel tube is machined
inside and out. This creates expense in the material, in the
machining time, and in the construction.
[0009] Other liner hangers have been constructed with a
single-piece mandrel or barrel. In this case, the cylinder or
J-Cage is connected to the barrel using mechanical means such as
set screws, wirelocks, or welding. The cones are generally integral
to the barrel as described above, but in some prior art embodiments
the cones may have been welded to the barrel, which adds cost and
time to the production. In addition, because of the complexity and
cost of the tool construction, it is impractical to create stock
items.
[0010] Welding the cones or the cylinder to the barrel or casing
mandrel requires multiple welds. These welds add time and expense
to the manufacture of the liner hanger. More importantly, welding
can affect the metallurgy of the barrel, making the welded area
subject to attack, for example by corrosive well fluids. As such,
welding to the barrel or to a casing mandrel is at minimum
undesirable, and may be prohibited under certain industry standard
regulations. As such, mechanical connections are preferable.
[0011] The disadvantages of two-piece liner hanger, and the
single-piece welded liner hanger, are overcome by the present
invention.
SUMMARY OF THE INVENTION
[0012] It is an aspect of the current invention that a liner
hanger, whether mechanical or hydraulic, may be constructed in a
modular fashion. The cones are attached to a barrel or mandrel in a
manner that is mechanical, does not require welding, and is highly
resistant to axial movement. It is a further aspect of the
invention that the mechanical connection is made using non-adhesive
components combined in such a manner that they will resist the high
temperatures, high pressures, and corrosive fluids and gases that
may be encountered in the well.
[0013] In the embodiment described herein, the present invention
provides a high-strength non-welded mechanical connection between
the cones of a liner hanger and a barrel or mandrel. As such, the
liner hanger can be built using standard stock casing, reducing the
over-all expense. In general, the liner hanger includes at least
one set of cones and slips.
[0014] One or more grooves or channels are cut in an outer wall of
the barrel. In preferred embodiments, the groove or channel is
sufficiently shallow to avoid significantly thinning the wall
thickness of the barrel. The inside surface of the cones contains
at least one partially or fully annular slot or groove oriented to
correspond with the groove(s) in the outer wall of the casing
mandrel.
[0015] At least one lock is situated in the corresponding slot and
the groove. The lock engages the flanks of the slot and groove
sufficiently to resist shears loads applied by the weight of the
liner that is hung off, and axial movement during running in the
hanger. In a preferred embodiment, the lock is one or more wires,
although other mechanical locking devices may be installed to
provide the same function.
[0016] The cones of the liner hanger, as well as the cylinder and
slips, can be easily installed on, or removed from the barrel. A
standard size barrel can accommodate cones and slips of various
sizes as needed for the characteristics of a particular well, the
piston or J-Cage area needed, and the weight of the particular
length of liner to be hung off the liner hanger. As such, the
system of the current invention provides a liner hanger that is
constructed of separately built and stored modules, and one that
uses mechanical non-welded connections.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1A is an elevation of an upper portion of a prior art
liner hanger with a two-piece barrel;
[0018] FIG. 1B is an elevation of a lower portion of a prior art
liner hanger with a two-piece barrel;
[0019] FIG. 2A is a partial sectional elevation of an upper portion
of a hydraulically actuated modular liner hanger;
[0020] FIG. 2B is a partial sectional elevation of a lower upper
portion of a hydraulically actuated modular liner hanger;
[0021] FIG. 3 is a partial sectional elevation of cones connected
to the liner hanger;
[0022] FIG. 4 is a second partial sectional elevation of cones
connected to the liner hanger, shown at a different radial
location;
[0023] FIG. 5 is a cross section of the hydraulically actuated
modular liner hanger shown in FIG. 2;
[0024] FIG. 6 is a partial sectional elevation of a hydraulic
actuation mechanism of the modular liner hanger;
[0025] FIG. 7A is a sectional elevation of an upper portion of a
mechanically actuated modular liner hanger; and
[0026] FIG. 7B is a sectional elevation of a lower portion of a
mechanically actuated modular liner hanger.
DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0027] In FIGS. 2A and 2B, an upper and lower portion of a
hydraulic-set modular liner hanger 10 are shown. Partial figures
are meant to show certain aspects of embodiments of the invention,
and are not necessarily continuous.
[0028] The modular liner hanger comprises a body or barrel 20,
which may also be called a mandrel or casing mandrel, or a liner
hanger body. Barrel 20 is generally cylindrical and contains a
generally cylindrical internal through bore 22. The barrel may be
made out of standard size and standard material casing that is well
known in the oilfield practice, or can be made out of specialty
pipe sizes or materials. At one end the barrel 20 may contain a
tapered and threaded portion 24 for connection to a running string,
liner packer, and/or liner setting tools (not shown).
[0029] A first set of cones or cone pads 50 is journalled about the
barrel 20. Cones 50 are separately machined pieces, and can be
constructed of various materials and in various sizes as desired
for a particular application. Cones 50 may include two or more cone
pads spaced around the circumference; three are shown in the
embodiment in the figures herein.
[0030] It is a particular aspect of the current invention to
provide a modular constructed liner hanger wherein the cones and
cylinders are mechanically joined to the barrel in a manner that
restricts both axial movement and rotation between the cones and
cylinder relative to the barrel. For this reason, prior liner
hangers have generally been constructed with the cones integral or
welded to the casing mandrel, and the cylinder constructed of a
separate barrel section with a threaded connection. The present
invention provides a one-piece construction and avoids welding, or
reduces the total number of welds.
[0031] In one embodiment of the current invention, as shown in
FIGS. 2A, 3, and 4, one or more grooves, or a series of radial
grooves 26, are cut in the external wall of the barrel 20. Grooves
26 need not be deeply cut into the outside diameter of the barrel
20, and could be little more than indentations, aligned with a
series of one or more corresponding annular grooves 52 in the inner
wall of the cones 50. Each annular groove 52 is connected to a
lateral bore 54 between the groove and the external surface of the
cones 50. Referring now to FIGS. 3 and 5, cones 50 also contain a
series of concave portions 56 that allow the passage of fluid.
Concave portions 56 may alternatively be a series of axial slots,
bores, or other means for allowing flowby of a sufficient volume of
fluid. In other embodiments, cone pads 50 may be a single cone or
may be multiple disjointed cones individually installed.
[0032] As shown in FIGS. 2A and 3, with the cones 50 journalled
about the barrel 20, and the grooves or indents 26 and 52 aligned,
a wire or series of wires 60 can be disposed in the grooves 26 and
52. Wires 60 can be installed through the lateral bores 54, cut to
appropriate lengths, and the opening of the lateral bores 54 closed
if desired.
[0033] Wires 60 bear on the flanks of grooves 26 and 52 to resist
axial movement of the cones 50 relative to the barrel 20. In a
preferred embodiment, the yield point of wires 60 will be greater
than the yield point of the barrel 20 and the cones 50.
[0034] In alternate embodiments, grooves 26 and 50 could be single
helical grooves, and a single wire 60 could be threaded into the
helical grooves. In addition, the grooves could be full or partial
channels, keyways, or other passageways. Wires 60 could be replaced
by a series of ball bearings sized for the grooves or other
passageways, roller-type bearings, or keys.
[0035] A keyway 28 is machined into the outer wall of barrel 20.
Key 58 is installed in a the keyway and a corresponding slot in the
cones 50 to resist relative rotation and to keep the cones properly
aligned. In an alternate embodiment, the cones may not be keyed to
the barrel, thus allowing relative rotation.
[0036] Referring again to FIG. 2A, journalled below the cones 50
are a corresponding first set of slips 70. Slips 70 contain a
serrated portion 72. The first set of slips 70 is connected to a
first end of one or more slip arms 80 by screws 74, or by other
known fastening means.
[0037] Slip arm 80 extends from the first set of slips 70 to a
hydraulic setting mechanism, or to the second set of slips 100
located lower on the barrel 20. The slip arms 80 transfer the
initial setting force from the hydraulic setting mechanism.
Although two sets of slips are shown, in other embodiments there is
only one set of slips, or there may be three or more. Such
variations are determined based on the required liner length,
hanging capacity, and well conditions, and/or to minimize stress in
the supporting casing. The slip arms may be radially offset, as in
the embodiment shown.
[0038] A slip arm support ring 82 may be installed between the
barrel 20 and the slip arm 80 to stiffen the slip arm 80 as may be
necessary based on the arrangement of, and distance between, cones
50 and 90. The second set of cones 90 may be radially offset from
the first set of cones 50.
[0039] Similar to the attachment of cones 50 to the barrel 20, in
the embodiment shown, grooves 30 are cut in the external wall of
the barrel 20. Grooves 30 are aligned with a second series of one
or more corresponding annular grooves 92 in the inner wall of the
second set of cones 90. Each groove 92 may be connected to a
lateral bore (not shown but which are similar to bore 54) between
the groove 92 and the surface of the cones 90. Cones 90 are
journalled about the barrel 20, and the grooves 30 and 92 are
aligned so that a wire or series of wires 62 can be disposed in the
grooves 30 and 92. Wires 62 may have a higher yield point relative
to the barrel 20 and the cones 90. Grooves 30 and 92 could be
single helical grooves with a single wire 62. The grooves could be
full or partial channels, keyways, or other passageways. Wires 62
could be replaced by a series of ball bearings sized for the
grooves or other passageways, roller-type bearings, or wires or
keys.
[0040] A second keyway (not shown) may be machined into the outer
wall of barrel 20, and a second key may be installed in the keyway
and a mating slot in the cones 90 to resist relative rotation and
to keep the cones 90 properly aligned.
[0041] Second set of slips 100 may be radially offset from the
first set of slips 70, but is aligned with the second set of cone
pads 90. The second set of slips 100 also contains a serrated
portion 102. The serrated portions 72 and 102 of the slips 70 and
100 are sufficiently hardened to allow setting into the particular
grade of casing in the well.
[0042] The second set of slips 100 is coupled to a second slip arm
110 by any mechanical means, for example, the screws 112 shown.
Slip arms 80 and 100 are coupled to a setting mechanism 120. In one
embodiment, setting mechanism 120 includes limit ring 135. Slip
arms 80 and 110 are coupled to the setting sleeve 136.
[0043] As shown in FIGS. 2B and 6, a cylinder 132 is also
journalled about the barrel 20. Cylinder 132 has a counterbore area
that, together with the outer wall of barrel 20, piston 138 and
associated seals 139, seal 133, and gage ring 140 create a chamber
144. A port 36 in barrel 20 allows the passage of fluid from the
throughbore 22 to chamber 144. Thus when the hydraulic liner hanger
10 has reached its desired position, a ball or dart is dropped and
lands in a seat or receptacle resulting in a pressure increase as
additional fluid is pumped down the string. The cylinder 132 may be
shear pinned to actuate at a predetermined pressure value. At the
desired pressure, the piston 138 moves upward, driving the setting
sleeve 136 upward. Setting sleeve 136 is slotted such that the
slots 137 allow travel upward and downward, but set screws 134
located in the slots 137 restrain rotation of the setting sleeve
136 relative to the barrel 20. With the piston 138 travelling
upward, the force is transferred from the setting sleeve 136 to the
slip arms 80 and 110. This causes slips 70 and 100 to come in
contact with the cones 50 and 90, and to be expanded outward until
serrated edges 72 and 102 and in gripping relation with the casing.
In conjunction with shoulder 146, limit ring 135 provides a backup
to set screws 134 in restraining the maximum travel distance for
the slip arms 80 and 110.
[0044] Gage ring 140 provides the base for the chamber 144. Barrel
20 contains a third set of grooves 34 cut in the external wall of
the barrel 20. Grooves 34 are aligned with another series of one or
more corresponding annular grooves 142 in the inner wall of the
gage ring 140. Each groove 142 may be connected to a lateral bore.
Gage ring 140 is journalled about the barrel 20 such that the
grooves 34 and 142 are aligned and a third wire or series of wires
64 can be disposed in the grooves 34 and 142. Wires 64 may have a
higher yield point relative to the barrel 20 and the gage ring 140.
Grooves 34 and 142 could be single helical grooves with a single
wire 64. The grooves could be full or partial channels, keyways, or
other passageways. Wires 64 could be replaced by a series of ball
bearings sized for the grooves or other passageways, roller-type
bearings, or wires.
[0045] Setting mechanism 120 and/or cylinder 132 may have an area
of larger outside diameter to protect the slips 70 and 100 and slip
arms 80 and 110 during running of the liner hanger 10. In addition,
at the distal end of barrel 20 there may be a tapered and threaded
portion 38 for connection to a liner packer, and/or liner setting
tools (not shown).
[0046] As can be seen, the cones 50 and 90, and the gage ring 140
of setting mechanism 120 are connected to the barrel or casing
mandrel 20 by means of one or more wirelocks, or similar mechanical
type connections, without the need for welding. It can also be seen
that the body of the liner hanger 20 has a generally uniform wall
thickness in the portion of the liner hanger where the cones 50 and
90 and the gage ring 140 are journalled and coupled, thus the tool
need not be manufactured from heavy wall pipe.
[0047] In an embodiment shown in FIGS. 7A and 7B, one possible
version of a mechanical set liner hanger in accordance with the
current invention is illustrated. Mechanical set liner hanger 150,
is comprised of barrel 220, one or more set of cone pads 250 and
290, and slips 270 and 300 associated with the cone pads 250 and
290. The cones 250 and 290 are attached to the barrel 220 using
mechanical non-welded connections, which can be a wirelock
mechanism as detailed in FIGS. 3 and 4. The cones 250 and 290
contain one or more grooves 252 and 292 that are aligned with
channels or grooves 226 and 230 in the outer wall of the barrel
220. One or more wires 260 and 262, bearings, or other mechanical
apparatus sufficiently stress resistant, are installed in the
mating grooves 226 and 252, and 230 and 292, in the cones and
barrel. Locked in this manner, the cones 250 and 290 are held in a
manner that resists axial loads and restricts axial movement of the
cones 250 and 290 relative to the barrel 220. Cones 250 and 290 may
be keyed to the barrel 220 using keys 258 and 296 installed in the
barrel keyways 228 and 232, to resist rotation of the cones
relative to the barrel.
[0048] The slips 270 and 300 in mechanical set liner hanger 150 are
driven by J-Cage 360. The J-Cage 360 contains a J-shaped slot 362.
A lug 364 is positioned within the J-shaped slot 362. During the
running of the mechanical set liner hanger 150, the lug 364 is held
against the short leg of the slot 362 because of the drag forces on
the J-Cage 360 which is in contact with the casing (not shown).
When the hanger is in the desired location in the well, the
mechanical hanger 150 is set by lifting the work string to release
the lug 364 from the short leg of the slot 362. The mechanical
hanger 150 is then rotated, to the right for right-hand set, and to
the left if left-hand set, to shift the lug to the long leg of the
J-shaped slot 362 and to align the slips 270 and 300 with the cones
250 and 290. With the cones 250 and 290 and slips 270 and 300
aligned, downward motion of the work string brings the cones 250
and 290 into contact with the slips 270 and 300, expanding the
serrated edges of the slips 270 and 300 into the casing wall. The
weight of the liner is transferred through the slips 270 and 300
into the surrounding casing to support the liner.
[0049] While the apparatus and methods of this invention have been
described in terms of preferred and illustrative embodiments, it
will be apparent to those of skill in the art that variations may
be applied without departing from the concept and scope of the
invention. All such similar substitutes and modifications apparent
to those skilled in the art are deemed to be within the scope and
concept of the invention.
* * * * *