U.S. patent application number 15/168658 was filed with the patent office on 2017-11-30 for composite body lock ring for a borehole plug with a lower slip assembly.
This patent application is currently assigned to BAKER HUGHES INCORPORATED. The applicant listed for this patent is BAKER HUGHES INCORPORATED. Invention is credited to Ryan M. Allen, Steve Rosenblatt, James S. Sanchez, Zachary S. Silva.
Application Number | 20170342794 15/168658 |
Document ID | / |
Family ID | 60421062 |
Filed Date | 2017-11-30 |
United States Patent
Application |
20170342794 |
Kind Code |
A1 |
Silva; Zachary S. ; et
al. |
November 30, 2017 |
Composite Body Lock Ring for a Borehole Plug with a Lower Slip
Assembly
Abstract
A borehole plug or packer for treating is designed to be milled
out after use. The plug handles differential pressure from above
using a lower slip assembly under a sealing element. A setting tool
creates relative axial movement of a setting sleeve and a plug
mandrel to compress the seal against the surrounding tubular and
set the slips moving up a cone against the surrounding tubular to
define the set position for the plug. The set position is held by a
split lock ring having a wedge or triangular sectional shape and a
surface treatment facing the mandrel that slides along the mandrel
during setting movement but resists opposed reaction force from the
compressed sealing element. The surface treatment can be a series
of downhole oriented ridges such as a buttress thread that
preferably penetrate the mandrel when holding the set position.
Inventors: |
Silva; Zachary S.; (Houston,
TX) ; Sanchez; James S.; (Tomball, TX) ;
Allen; Ryan M.; (Cypress, TX) ; Rosenblatt;
Steve; (Houston, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BAKER HUGHES INCORPORATED |
Houston |
TX |
US |
|
|
Assignee: |
BAKER HUGHES INCORPORATED
Houston
TX
|
Family ID: |
60421062 |
Appl. No.: |
15/168658 |
Filed: |
May 31, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 33/12 20130101;
E21B 33/129 20130101 |
International
Class: |
E21B 33/12 20060101
E21B033/12; E21B 33/129 20060101 E21B033/129 |
Claims
1. A plug or packer assembly for borehole use, comprising: a
mandrel supporting a sealing element and a retaining member
disposed between said sealing element and one of opposed ends of
said mandrel; a lock ring having a surface treatment facing said
mandrel, said surface treatment oriented toward a second of said
ends of said mandrel, said surface treatment configured for sliding
contact with an outer surface of said mandrel when moving toward a
first of said ends for setting said sealing element and said
retaining member and said surface treatment configured to penetrate
said outer surface of said mandrel when moving toward said second
end.
2. The assembly of claim 1, wherein: said lock ring comprising a
tapered surface opposite said surface treatment.
3. The assembly of claim 1, wherein: said lock ring comprises a
split ring.
4. The assembly of claim 1, wherein: said lock ring comprises
spaced segments.
5. The assembly of claim 1, wherein: said lock ring is rotationally
locked to said mandrel.
6. The assembly of claim 1, wherein: said surface treatment
comprises a plurality of ribs oriented toward said second end, said
second end oriented downhole from said first end.
7. The assembly of claim 6, wherein: said ribs are parallel.
8. The assembly of claim 6, wherein: said ribs comprise a
spiral.
9. The assembly of claim 6, wherein: said ribs comprise a thread
form.
10. The assembly of claim 6, wherein: said ribs are evenly or
unevenly spaced.
11. The assembly of claim 1, wherein: said lock ring comprises a
triangle shape in section.
12. The assembly of claim 11, wherein: said retaining member
comprises slips; said slips are retained to said mandrel by a slip
retainer ring defining at least one undercut conforming to the
shape of said lock ring.
13. The assembly of claim 12, wherein: said undercut and lock ring
comprise aligned tapered surfaces with respect to said outer
surface of said mandrel such that movement of said slip retainer
ring against said lock ring in response to a reaction force from a
set said sealing element pushes said surface treatment to penetrate
said outer surface of said mandrel.
14. The assembly of claim 13, wherein: said tapered surfaces apply
a radial and axial component forces to said surface treatment.
15. The assembly of claim 14, wherein: said surface treatment
comprises a plurality of ribs oriented toward said second end, said
second end oriented downhole from said first end.
16. The assembly of claim 15, wherein: said ribs are parallel.
17. The assembly of claim 15, wherein: said ribs comprise a
spiral.
18. The assembly of claim 15, wherein: said ribs comprise a thread
form.
19. The assembly of claim 15, wherein: said ribs are evenly or
unevenly spaced.
20. A treatment method for borehole use, comprising running in a
packer or plug mandrel supporting a sealing element and a retaining
member disposed between said sealing element and one of opposed
ends of said mandrel and a lock ring having a surface treatment
facing said mandrel, said surface treatment oriented toward a
second of said ends of said mandrel, said surface treatment
configured for sliding contact with an outer surface of said
mandrel when moving toward a first of said ends for setting said
sealing element and said retaining member and said surface
treatment configured to penetrate said outer surface of said
mandrel when moving toward said second end; setting said sealing
element and retaining member; pumping a treatment into the borehole
against said packer or plug.
21. A plug or packer assembly for borehole use, comprising: a
mandrel supporting a sealing element and a retaining member
disposed between said sealing element and one of opposed ends of
said mandrel; a lock ring facing said mandrel, comprising a surface
configured for sliding contact with an outer surface of said
mandrel when moving toward a first of said ends for setting said
sealing element and said retaining member and said surface
configured to frictionally engage using wedging action said outer
surface of said mandrel when moving toward said second end.
22. A treatment method for borehole use, comprising running in a
packer or plug mandrel supporting a sealing element and a retaining
member disposed between said sealing element and one of opposed
ends of said mandrel and a lock ring facing said mandrel,
comprising a surface configured for sliding contact with an outer
surface of said mandrel when moving toward a first of said ends for
setting said sealing element and said retaining member and said
surface configured to frictionally engage using wedging action said
outer surface of said mandrel when moving toward said second end
setting said sealing element and retaining member; pumping a
treatment into the borehole against said packer or plug.
Description
FIELD OF THE INVENTION
[0001] The field of the invention is borehole barriers and more
particularly designs that see pressure from above and use materials
the mill easily for removal after use and which lock in a set
position for use.
BACKGROUND OF THE INVENTION
[0002] Borehole plugs are used in a variety of applications for
zone isolation. In some applications the differential pressure
experienced in the set position can come from opposed directions.
These plug typically have a sealing element with mirror image slips
above and below the sealing element. The plug is set with a setting
tool that creates relative movement between a setting sleeve that
is outside the mandrel and the plug mandrel. The slips have wickers
oriented in opposed directions and ride out on cones to the
surrounding tubular. The sealing element is axially compressed
after the first set of slips bite followed by setting of the other
set of slips on the opposite side of the sealing element from the
first slip set to set. The set position of these elements is
maintained by a body lock ring assembly. Body lock ring assemblies
are in essence a ratchet device that allows relative movement in
one direction and prevents relative movement in the opposite
direction. The relative movement that compresses the sealing
element and drives the opposed slips out on respective cones is
locked by a body lock ring. Body lock rings are threaded inside and
out and sit between tow relatively movable components. The thread
forms are such that ratcheting in one direction only is enabled. A
good view of such a design is shown in FIG. 13 of U.S. Pat. No.
7,080,693. The trouble with such a design in applications where the
plug needs to be quickly milled out after use such as in treating
or fracturing is that the shear loading on the ratcheting patterns
is so high that the ratchet teeth break at loads that are well
within the needed operating pressure range for the plug. With
fracturing pressures going up and the use of readily milled
components such as composites a new approach to locking was need
and provided by the present invention. The goal is to hold the
differential pressure from above while keeping the design simple so
as not to prolong the milling time for ultimate removal. A typical
zone treatment can involve multiple plugs that need to be removed.
Elimination of upper slips when using the lock ring of the present
invention also shortens milling time.
[0003] The lock ring is preferably split to ease its movement when
axial opposed forces are applied to set the plug. The ring is
tapered in cross section to allow it to act as a wedge against
reaction force tending to relax the components from the set
position. The side of the ring facing the mandrel has a surface
treatment that provides minimal resistance in the setting direction
and digs into the mandrel to resist reaction forces from the
compressed sealing element in the set position. Preferably the
surface treatment is a series of extending members oriented
downhole with sharp ends that can dig into the mandrel for a firm
grip. These and other aspects of the present invention can be
better understood by those skilled in the art from a review of the
description of the preferred embodiment and the associated drawings
while recognizing that the full scope of the invention is to be
determined from the appended claims.
[0004] Multicomponent body lock rings have been made of easily
milled materials such as composites as illustrated in US
2014/0190685; U.S. Pat. No. 8,191,633; U.S. Pat. No. 6,167,963;
U.S. Pat. No. 7,036,602; U.S. Pat. No. 8,002,030 and U.S. Pat. No.
7,389,823.
SUMMARY OF THE INVENTION
[0005] A borehole plug or packer for treating is designed to be
milled out after use. The plug handles differential pressure from
above using a lower slip assembly under a sealing element. A
setting tool creates relative axial movement of a setting sleeve
and a plug mandrel to compress the seal against the surrounding
tubular and set the slips moving up a cone against the surrounding
tubular to define the set position for the plug. The set position
is held by a split lock ring having a wedge or triangular sectional
shape and a surface treatment facing the mandrel that slides along
the mandrel during setting movement but resists opposed reaction
force from the compressed sealing element. The surface treatment
can be a series of downhole oriented ridges such as a buttress
thread that preferably penetrate the mandrel when holding the set
position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a section view of the plug in the run in
position;
[0007] FIG. 2 is a close up view of the lock ring shown in FIG. 1
and
[0008] FIG. 3 is an exterior view of the plug.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0009] Referring to FIG. 1 the plug or packer 10 has a mandrel 12
preferably made of a readily milled material such as a composite.
Mandrel 12 can optionally have a passage 13 that can be optionally
closed with a ball landed on a seat or with a valve (not shown).
Shoulder 14 supports sealing element 16. A cone 18 has
individualized tapered surfaces 20 on which a slip 22 is guided
between opposed surfaces 24 and 26. The slips 22 are each connected
to a slip ring 28 that has a triangular undercut 30 when viewed in
section in FIG. 1 that extends for 360 degrees, preferably. The
undercut is defined by surfaces 32 and 34 as better seen in FIG. 2.
Lock ring 36 has an outer surface 38 that is preferably parallel to
surface 32 of undercut 30. Bottom surface 40 of ring 36 is
contacted by surface 34 of undercut 30 during the setting process.
A shear pin or some other breakable member 42 allows the sealing
element 16 to be compressed against a surrounding tubular that is
not shown before the slips 22 are released to move up ramp surfaces
20 by the breaking of the shear pin 42. Movement of ring 28
relative to mandrel 12 brings together surfaces 34 and 40 to push
the lock ring 36 in tandem with ring 28 during setting with a
setting tool that is well known and is not shown and which serves
as the force to brace the mandrel 12 while applying compressive
force to the sealing element 16 and then extending the slips 22
against the surrounding tubular. The slips 22 have a surface
treatment such as wickers 44 that resist reaction force from the
compressed sealing element 16 as well as applied pressure loads
from uphole applied in the direction of arrow 46.
[0010] The lock ring 36 has a surface treatment 48 on bottom
surface 50 that faces the mandrel 12. During setting when the ring
28 takes lock ring 36 with it the surface treatment 48 rides along
surface 54 of mandrel 12 without penetration of surface 54.
However, after the set and release from the plug by the setting
tool the reaction force from the sealing element 16 causes the
downhole oriented ribs 56 to penetrate the surface of the mandrel
12 to brace the lock ring 36 so that it can act as a wedge using
surface 38 to prevent motion of ring 28 in the direction of arrow
46.
[0011] Lock ring 36 can run continuously for nearly 360 with a
single split to facilitate assembly to the mandrel 12.
Alternatively, there can be discrete spaced segments for the
majority of the 360 degree extent of the undercut 30. Undercut 30
can be continuous or discontinuous for 360 degrees to retain lock
ring 36 when lock ring 36 is formed of discrete segments. The
wedging action between surfaces 32 and 38 reduces the stress in an
axial direction parallel to surface 54 to discourage shear failure
of the ribs 56 while the preferred composite construction of the
mandrel 12 encourages penetration through surface 54. The wedging
action creates a radial and axial component forces to the ribs 56
to increase the penetration into the mandrel 12 and to decrease the
axial shear force component acting on the ribs 56 at the outer
surface of said mandrel 12. The ribs 56 can be parallel or one or
more spiral patterns or a thread form such as a buttress thread.
The rib spacing can be equal or variable. The lock ring 36 can
preferably be made of composite material or a soft metallic that
can be easily drilled. Optionally, if lock ring 36 is a continuous
split ring the faces 58 and 60 that define the split can be placed
on opposed sides of a tab 62 on mandrel 12 to rotationally lock the
two together to prevent lock ring relative rotation with respect to
the mandrel 12 when milling out. When segments are used for the
lock ring 36 each segment can be rotationally retained in a
dedicated undercut 30 in ring 28 to rotationally secure the
components when milling out. Alternatively, some or all of the
above described plug 10 apart from sealing element 16 can be made
of a disintegrating controlled electrolytic material to forgo the
milling out altogether.
[0012] Optionally the ribs 56 can be omitted so that bottom surface
50 can make frictional contact with surface 54 with no or minimal
penetration so that the retaining force is principally or entirely
a frictional contact. Surface 50 can have surface roughening or it
can even be smooth. While the ability to hold reaction force may be
somewhat decreased without the ribs 50 there is still enough
resistance to reaction force to hold the set position for some
applications. Wedging action creates the frictional retention
force.
[0013] The teachings of the present disclosure may be used in a
variety of well operations. These operations may involve using one
or more treatment agents to treat a formation, the fluids resident
in a formation, a wellbore, and/or equipment in the wellbore, such
as production tubing. The treatment agents may be in the form of
liquids, gases, solids, semi-solids, and mixtures thereof.
Illustrative treatment agents include, but are not limited to,
fracturing fluids, acids, steam, water, brine, anti-corrosion
agents, cement, permeability modifiers, drilling muds, emulsifiers,
demulsifiers, tracers, flow improvers etc. Illustrative well
operations include, but are not limited to, hydraulic fracturing,
stimulation, tracer injection, cleaning, acidizing, steam
injection, water flooding, cementing, etc.
[0014] The above description is illustrative of the preferred
embodiment and many modifications may be made by those skilled in
the art without departing from the invention whose scope is to be
determined from the literal and equivalent scope of the claims
below:
* * * * *