U.S. patent application number 14/932184 was filed with the patent office on 2016-08-18 for plunger lift assembly.
The applicant listed for this patent is Roland McDavid, Brandon Williams. Invention is credited to Roland McDavid, Brandon Williams.
Application Number | 20160238002 14/932184 |
Document ID | / |
Family ID | 56620925 |
Filed Date | 2016-08-18 |
United States Patent
Application |
20160238002 |
Kind Code |
A1 |
Williams; Brandon ; et
al. |
August 18, 2016 |
PLUNGER LIFT ASSEMBLY
Abstract
The present application includes a plunger assembly having an
internally coupled clutch assembly within a cage. The clutch
retainer assembly is free from direct impact with objects at the
bottom of the well that may cause damage to the clutch assembly.
The clutch assembly includes a multi-piece clutch to contact a stem
within the cage. One or more retainers are used to maintain the
orientation and alignment of the clutch within the cage. The cage
includes a linear taper to increase wall thicknesses and further
includes one or more flow cuts along the exterior surface of the
wall to increase the volume of fluid that can enter through the one
or more ports in the cage.
Inventors: |
Williams; Brandon; (Aledo,
TX) ; McDavid; Roland; (Aledo, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Williams; Brandon
McDavid; Roland |
Aledo
Aledo |
TX
TX |
US
US |
|
|
Family ID: |
56620925 |
Appl. No.: |
14/932184 |
Filed: |
November 4, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62116628 |
Feb 16, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04B 47/00 20130101;
E21B 43/121 20130101; F04B 53/14 20130101; F04B 47/02 20130101 |
International
Class: |
F04B 53/14 20060101
F04B053/14; F04B 47/00 20060101 F04B047/00; E21B 43/12 20060101
E21B043/12 |
Claims
1. A plunger assembly for use in a well, comprising: a mandrel; a
cage coupled to the mandrel, the cage and the mandrel forming a
body; an internal stem configured to translate within the cage and
outside of the mandrel, the stem configured to selectively regulate
the flow of fluid through the mandrel; and an internal clutch
assembly coupled internally within the cage, the internal clutch
assembly including a clutch configured to engage the stem.
2. The plunger assembly of claim 1, wherein the clutch is
partitioned into a plurality of equally sized radial portions.
3. The plunger assembly of claim 1, wherein the clutch includes at
least three radial portions.
4. The plunger assembly of claim 3, wherein the three radial
portions are equally sized.
5. The plunger assembly of claim 1, wherein the clutch includes a
groove configured to accept a ring, the ring configured to maintain
the alignment and orientation of the clutch.
6. The plunger assembly of claim 1, further comprising: a ring
configured to maintain the alignment and orientation of a clutch
within the internal clutch assembly, the ring housed within a
groove in the clutch.
7. The plunger assembly of claim 1, wherein the internal clutch
assembly further includes a band configured to wrap around a
central body of the clutch, the band being configured to hold the
clutch together.
8. The plunger assembly of claim 7, wherein the band is retained
around the body of the clutch and restricted from sliding off the
central body of the clutch.
9. The plunger assembly of claim 7, wherein the internal clutch
assembly uses one or more dissimilar bands.
10. The plunger assembly of claim 9, wherein the bands of the
internal clutch assembly are layered to vary the pressure applied
to the stem.
11. The plunger assembly of claim 7, wherein the band may be at
least one of a low load unobtrusive band and an elastomeric
bands.
12. The plunger assembly of claim 1, wherein the cage is configured
to gradually taper from an upper end in communication with the
mandrel to a lower end opposite the upper end, the taper configured
to maintain a linear reduction in surface area, the linear
reduction permits for an increased thickness to assist in absorbing
impact forces at the bottom of the well.
13. The plunger assembly of claim 1, wherein the cage includes one
or more flow cuts formed into the outer surface of the cage, the
flow cuts being reduced thickness areas in the wall of the
cage.
14. The plunger assembly of claim 13, wherein the flow cut is
configured to reduce the distance between a portion of the cage and
an internal surface of the well so as to permit for the increased
flow of fluid into the mandrel.
15. The plunger assembly of claim 14, wherein the cage includes at
least two flow cuts.
16. The plunger assembly of claim 14, wherein the flow cuts are
equally spaced radially around the cage.
17. The plunger assembly of claim 1, wherein the cage includes one
or more ports in the wall of the cage and configured to permit the
passage of fluid into the mandrel.
18. The plunger assembly of claim 17, wherein the one or more ports
are located in a flow cut of the cage, the flow cut being a reduced
thickness portion of the cage.
19. The plunger assembly of claim 1, wherein the internal clutch
assembly is configured to control external pressures applied to the
internal stem.
Description
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates generally to oil field tools,
and more particularly to an improved plunger lift assembly.
[0003] 2. Description of Related Art
[0004] The oil and gas industry has been drilling and completing
wells to produce hydrocarbons for decades. Plungers are downhole
tools used by operators to remove liquids and contaminants from
productive natural gas wells. A plunger acts as an artificial lift.
In operation the plunger passes down through the well until it
reaches a contact point in which the plunger seals shut. Pressure
beneath the plunger builds and raises the plunger in the well,
thereby removing all the liquids above the plunger.
[0005] A number of disadvantages exist with plungers. Bypass valve
style plungers may have an external clutch retainer. The clutch
retainer usually coupled directly to the cage. The cage and clutch
retainer are located at the lower end of the plunger and experience
great impact forces at the bottom of the well. The valve cage is
typically thin-walled and susceptible breakage from the impact
forces. Additionally, the clutch retainer being located externally,
experiences direct impact forces at the bottom of the well and can
be another failure point. When failed, pieces of the clutch and
damaged retainer break from the plunger in the well, requiring each
piece to be fished out, thereby increasing costs to the operator.
Another disadvantage of bypass valve style plungers is the clutch.
Clutches may typically be two-piece assemblies and use a spring
wire or elastomeric bands to apply pressure.
[0006] An improved plunger assembly design is needed. Although
great strides have been made, considerable shortcomings remain.
DESCRIPTION OF THE DRAWINGS
[0007] The novel features believed characteristic of the
application are set forth in the appended claims. However, the
application itself, as well as a preferred mode of use, and further
objectives and advantages thereof, will best be understood by
reference to the following detailed description when read in
conjunction with the accompanying drawings, wherein:
[0008] FIG. 1 is an exploded perspective view of a plunger assembly
according to the preferred embodiment of the present
application
[0009] FIG. 2 is an enlarged side section view of a portion of the
plunger assembly of FIG. 1;
[0010] FIGS. 3 and 4 are enlarged side section views illustrating a
stem used in the plunger lift assembly of FIG. 1 in two different
positions;
[0011] FIGS. 5-8 are associated views of an internal clutch
assembly used in the plunger lift assembly of FIG. 1;
[0012] FIGS. 9-10 are associated views of a clutch retainer used in
the plunger lift assembly of FIG. 1;
[0013] FIGS. 11-12 are associated views of a cage used in the
plunger lift assembly of FIG. 1; and
[0014] FIG. 13 is a bottom view of the cage of FIG. 12 showing
exemplary flow cut designs.
[0015] While the system and method of the present application is
susceptible to various modifications and alternative forms,
specific embodiments thereof have been shown by way of example in
the drawings and are herein described in detail. It should be
understood, however, that the description herein of specific
embodiments is not intended to limit the application to the
particular embodiment disclosed, but on the contrary, the intention
is to cover all modifications, equivalents, and alternatives
falling within the spirit and scope of the process of the present
application.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] Illustrative embodiments of the preferred embodiment are
described below. In the interest of clarity, not all features of an
actual implementation are described in this specification. It will
of course be appreciated that in the development of any such actual
embodiment, numerous implementation-specific decisions must be made
to achieve the developer's specific goals, such as compliance with
system-related and business-related constraints, which will vary
from one implementation to another. Moreover, it will be
appreciated that such a development effort might be complex and
time-consuming but would nevertheless be a routine undertaking for
those of ordinary skill in the art having the benefit of this
disclosure.
[0017] In the specification, reference may be made to the spatial
relationships between various components and to the spatial
orientation of various aspects of components as the devices are
depicted in the attached drawings. However, as will be recognized
by those skilled in the art after a complete reading of the present
application, the devices, members, apparatuses, etc. described
herein may be positioned in other desired orientations. Thus, the
use of terms to describe a spatial relationship between various
components or to describe the spatial orientation of aspects of
such components should be understood to describe a relative
relationship between the components or a spatial orientation of
aspects of such components, respectively, as the device described
herein may be oriented in other desired directions.
[0018] The system and method in accordance with the present
application overcomes one or more of the above-discussed problems
commonly associated with existing plunger assembly designs.
Specifically, the system of the present application is configured
to incorporate an internal clutch retainer, 3-piece clutch, and
improved cage. The cage is configured to assist in the passage of
liquids, hydrocarbons, and solids; and prevent premature wear and
breakage typically associated from impact forces. These and other
unique features of the system are discussed below and illustrated
in the accompanying drawings.
[0019] The assembly will be understood, both as to its structure
and operation, from the accompanying drawings, taken in conjunction
with the accompanying description. Several embodiments of the
assembly may be presented herein. It should be understood that
various components, parts, and features of the different
embodiments may be combined together and/or interchanged with one
another, all of which are within the scope of the present
application, even though not all variations and particular
embodiments are shown in the drawings. It should also be understood
that the mixing and matching of features, elements, and/or
functions between various embodiments is expressly contemplated
herein so that one of ordinary skill in the art would appreciate
from this disclosure that the features, elements, and/or functions
of one embodiment may be incorporated into another embodiment as
appropriate, unless otherwise described.
[0020] The system of the present application is configured to
translate within an oil/gas well. The plunger lift assembly is
configured to translate up and down through a well by selectively
permitting the passage of hydrocarbons, contaminants, and liquids
through an internal chamber. At the bottom of the well, the plunger
assembly is configured to impact a stop or bumper. The impact
forces are transferred through a cage to the body. The plunger
assembly includes the cage surrounding an internal clutch, a clutch
retainer, and a stem. The stem extends from a lower end of the cage
during the fall through the well. In this orientation,
hydrocarbons, liquids and contaminants are configured to pass
around the stem and through channels in the cage into the internal
chamber of a mandrel. This passage of fluid permits the plunger to
fall through contaminants and liquid in the well. Upon contact at
the designated location, the orientation of the stem changes within
the cage. The stem presses up within the cage and contacts a bottom
portion of the mandrel, thereby forming a seal and preventing the
future passage of liquid and contaminants through the internal
chamber. In this sealed condition, pressure builds up beneath the
plunger which eventually reaches a level where the pressure lifts
the plunger to the surface. At the same time, the liquid and
contaminants above the plunger are also brought to the surface. The
stem is unseated upon contact with the surface of the well.
[0021] Referring now to the figures wherein like reference
characters identify corresponding or similar elements in form and
function throughout the several views. The following Figures
describe assembly/system 101 and its associated features.
[0022] Referring now to FIG. 1 in the drawings, an exploded
perspective view of plunger assembly 101 is illustrated. Assembly
101 includes a mandrel 103, stem 105, clutch assembly 107, clutch
retainer 109, and cage 111. Cage 111 is configured to couple to an
end of mandrel 103 in a threaded relationship. Cage 111 and mandrel
103 are detachable. When coupled, cage 111 and mandrel 103 form the
body of assembly 101. Stem 105 is configured to translate within
cage 111 between at least two positions, outside of mandrel 103.
Stem 105 is configured to selectively regulate the flow of working
fluid through mandrel 103 by changing its position within cage 111.
Clutch assembly 107 is internally located within cage 111 along
with stem 105. Clutch assembly 107 is configured to engage a
portion of stem 105 while in both the first position and the second
position. Each part is described in further detail in the following
figures.
[0023] FIG. 2 illustrates a partial side section view of the
individual parts of assembly 101. From FIG. 2, an internal view of
cage 111 is more clearly seen. When assembled, each part is located
as illustrated in FIGS. 3 and 4. In particular, the two positions
of stem 105 are illustrated in FIGS. 3 and 4. Also of note is the
particular location of clutch retainer 109. Clutch retainer 109 is
located internally within cage 111. In particular, cage 111 is the
lowest part of assembly 101. Clutch assembly 107 is configured to
nestle against a lower internal lip of cage 111 within a formed
pocket of space. Clutch retainer 109 is in threaded attachment with
cage 111 and is located above clutch assembly 107. Therefore,
clutch assembly 107 is pressed down onto the lower internal lip of
cage 111 by the tightening of clutch retainer 109. FIGS. 3 and 4
more clearly illustrate the location of clutch retainer 109. In
this embodiment, clutch retainer is clearly internally housed
within cage 111 and is not subjected to direct contact with
external objects in the well, such as a bumper. By avoiding direct
contact with a bumper at the bottom of the well, the life of the
clutch is preserved. Impact forces are absorbed by cage 111.
[0024] FIGS. 3 and 4 are used to illustrate assembly 101 combined
and in operation with stem 105 oriented between two different
positions. As noted previously, when assembly 101 is traveling down
through a well, stem 105 is naturally in a protruding position such
that stem 105 is in a first position as seen in FIG. 4. The lower
part of the head portion of stem 105 is resting on, or slightly
above, clutch retainer 109. Hydrocarbons, liquids and contaminants
within the well are passed through various channels or gaps within
assembly 101, such as those formed in cage 111 to permit the
passage of working fluid through internal chamber 115 of mandrel
103.
[0025] FIG. 3, in particular, illustrates stem 105 in the second
position, wherein stem 105 is pressed against mandrel 103 by
contact with an external member in the well. The transition to the
second position occurs when assembly 101 impacts the bottom of the
well. The impact seats stem 105 in the second position. The impact
forces are absorbed predominantly through cage 111. In the second
position, stem 105 is flush with the bottom surface of cage 111 and
the upper surface of the head of stem 105 is pressed against a
lower portion of mandrel 103. The contact between mandrel 103 and
stem 105 forms a seal that cuts off the flow of fluid through
mandrel 103. Note that the head of stem 105 in FIG. 3 is above that
of various ports 113 located in the side of cage 111. The sealing
effect prevents the passage of fluid through internal chamber 115
and results in a pressure gradient between the liquid above
assembly 101 and that of the fluid below assembly 101. The pressure
gradient causes assembly 101 to rise to the surface of the well and
simultaneously remove the liquids and contaminants above it.
[0026] Stem 105 is illustrated as a cylindrical member having a
head portion at an upper end. The shape and size of stem 105 is
adapted to fit the sizing of assembly 101. Some embodiments may
utilize various types of surface treatments along the main shaft of
stem 105, such as threads or axial grooves to assist in the passing
of solids across the clutch, however in the preferred embodiment,
the main shaft of stem 105 is slightly textured as opposed to being
relatively smooth.
[0027] Referring now also to FIGS. 5-8 in the drawings, clutch
assembly 107 is illustrated. Clutch assembly 107 includes a clutch
117 illustrated in FIG. 5, a band 118 as seen in FIGS. 6A and 6B,
and a ring 117 shown in FIG. 7. Clutch 117 is configured to engage
the outer surface of stem 105 around the elongated shaft. Clutch
117 is a multi-member clutch wherein clutch 117 is partitioned into
a plurality of radial portions. The portions are equally sized and
spaced to permit equal surface contact with stem 105. Together, the
members of clutch 117 surround and contact the circumference of
stem 105. Clutch 117 is configured to permit a greater area of
contact with stem 105 for a better transitioning as stem 105
transitions between the first and second positions. Although clutch
117 is shown having three members, it is contemplated that clutch
117 may include more or less members. Additionally, the members may
be unequally sized in other embodiments as desired.
[0028] The respective positioning and orientation of the members of
clutch 117 are held together through one or more retainers. The
retainers are used to maintain the alignment and orientation of
clutch 117. As seen in FIG. 7, clutch assembly includes ring 119.
Ring 119 is configured to clip around a portion of clutch 117 to
restrict the ability of each member of clutch 117 from separating
from one another. Clutch 117 includes an upper and lower recessed
groove 114 located around the circumference of the external surface
of each member of clutch 117. Ring 119 is configured to rest within
groove 114. Ring 119 is configured to protrude away from the outer
surface 120 of clutch 117. The protruding rings 119 help to
maintain the alignment of clutch 117 relative to cage 111. Rings
119 may contact internal surfaces of the cage within the seat which
clutch 117 resides. It is understood that ring 119 is not limited
to the specific depictions of FIG. 7. Ring 119 may be formed as a
complete circle, without a gap, in other embodiments. The groove
depth for rings 119 can be cut deeper or shallower on the exterior
of clutch 117 to control external pressure applied to stem 105. The
depth of the grooves regulates the external pressure on stem 105.
Regulation of external pressures on stem 105 may also be
accomplished through the use of different types of rings 119.
[0029] In FIGS. 6A and 6B, bands 118 are illustrated. Bands 118 are
configured to wrap around a central body of the clutch members
between grooves 114. An example of bands 118 are Hoopster bands.
Bands 118 are bound between rings 119 so as to restrict the ability
of bands 118 from sliding off clutch 117. Bands 118 are configured
to provide additional strength and resistance to undesired movement
of the members of clutch 117. In this way, bands 118 are configured
to also maintain the alignment and orientation of the individual
members of clutch 117. One or more bands 118 may be used depending
on the size of each band. A slot 116 is maintained in each band to
ensure appropriate flexure of band 118 and may also allow band 118
to possibly expand sufficiently to pass over the body of clutch 117
if rings 119 are engaged. FIG. 8 illustrates a side view of clutch
117 with phantom lines representing interior edges.
[0030] As mentioned previously, it is desired to regulate external
pressures on stem 105. To accomplish this, clutch 117 may be
configured to be a variable pressure clutch system through the use
of different types of bands 118 and rings 119. The rings and bands
of clutch 117 may be constant section rings, low load unobtrusive
bands, and even elastomeric bands that fit on the outer parts of
clutch 117 between the grooves. One or more dissimilar styles may
be used simultaneously. Clutch 117 may optionally include an
elastomeric band layered over bands 118 and/or ring 119. The mixing
and matching of different bands 118 and rings 119 in one or more
layers selectively allows for clutch 117 to accommodate and
regulate varied external pressures on stem 105.
[0031] Referring now also to FIGS. 9 and 10 in the drawings, clutch
retainer 109 is illustrated. Retainer 109 is configured to be
located and secured within cage 111. Retainer 109 is located and
seated above clutch assembly 107. Retainer 109 may be secured in
various different ways. As depicted in the Figures, threaded
engagement is one such method. This allows for the removal of
retainer 109. Another method is to a pin that passes through a
portion of cage 111 and retainer 109 that is also spot welded to
cage 111 to prevent undesired removal. The weld prevents the
backing out of the pin. When using a pin, retainer 109 would be
torqued down to the desired level and then a hole would be drilled
through cage 111 and into a portion of retainer 109. The spot weld
would be done after inserting the pin into the hole and ensuring it
passes through into retainer 109. Stem 105 is configured to pass
through a central portion 124 of retainer 109. It is noted that
retainer 109 is internally located within cage 111 and is protected
from direct impact from the falling of plunger assembly 101 in the
well. If in the event of failure of assembly 101, the internally
mounted retainer 109 and clutch assembly 107 remain within cage 111
and are prevented from falling out into the well. This prevents the
need to fish the parts out of the well.
[0032] Referring now also to FIGS. 11-13 in the drawings, cage 111
is further illustrated. Cage 111 is shown in a perspective view
(see FIG. 11) and in a side section view (see FIG. 12). Threaded
locations are seen for attachment of cage 111 to mandrel 103 at an
upper portion, and a threaded location at a lower portion for
attachment with retainer 109. Cage 111 is a one piece member and is
configured to retain thicker walls so as to absorb the impact
forces at the bottom of the well without incurring damage. Cage 111
has a gradual taper from an upper end, in communication with the
mandrel, that slowly narrows down to a lower end opposite the upper
end. The taper is configured to maintain a linear reduction in
surface area from the upper end to the lower end of cage 111. This
linear reduction permits for an increased thickness to assist in
absorbing impact forces at the bottom of the well.
[0033] As noted previously, working fluid is configured to enter
cage 111 through ports 113 and pass through internal chamber 115.
As working fluid passes between the walls of the well and assembly
101, particulates may build up resulting in some restriction in
flow through ports 113. Cage 111 is configured to include one or
more flow cuts 121 formed into an outer surface of cage 111. Ports
or slots 113 are located on flats or flow cuts 121. The object and
purpose of the ports 113 and flow cuts 121 are to permit for the
increased flow of liquid through internal chamber 115. Importantly,
the liquid within the well may include contaminants that can build
up and have differing sized dimensions. The use of flow cuts 121
can provide a larger area for the passage of contaminants. This
reduces the chances of having to fish out the plunger from the well
due to failed operations of the stem in not sealing. The ports 113
and flow cuts 121 are possible because of the thickened walls of
cage 111. The thicker walls also help with absorbing impact forces
as noted above. It is understood that one or more ports 113 and or
flow cuts 121 are possible.
[0034] Flow cuts 121 are reduced thickness areas in the wall of the
cage. As seen in greater detail in FIG. 13, exemplary designs of
flow cuts 121 are illustrated and contemplated for use with
assembly 101. Flow cuts 121 are equally spaced around the
circumference of cage 111. Flow cuts 121 are configured to increase
the distance between cage 111 with ports 113 and that of the walls
of the well so as to minimize chances of restrictions and to
increase flow of working fluid through ports 113. Although flow
cuts 121 are illustrated as flat surfaces, it is understood that
the contour may be modified to include one or more radiused
surfaces.
[0035] The current assembly has many advantages over the prior art
including at least the following: 1) three-piece clutch for added
contact points with the stem; 2) an internally located clutch and
clutch retainer within the cage; 3) inclusion of thicker walls
within the cage; 4) inclusion of flow cuts in the outer surface of
the cage; 5) Variable pressure clutch assembly; and 6) multiple
bands used around the clutch.
[0036] The particular embodiments disclosed above are illustrative
only, as the application may be modified and practiced in different
but equivalent manners apparent to those skilled in the art having
the benefit of the teachings herein. It is therefore evident that
the particular embodiments disclosed above may be altered or
modified, and all such variations are considered within the scope
and spirit of the application. Accordingly, the protection sought
herein is as set forth in the description. It is apparent that an
application with significant advantages has been described and
illustrated. Although the present application is shown in a limited
number of forms, it is not limited to just these forms, but is
amenable to various changes and modifications without departing
from the spirit thereof.
* * * * *