Note: Descriptions are shown in the official language in which they were submitted.
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EX.PItESS MAUL LABEL NO. EV222929067~75 PATENT
CHECK ENHANCER
BACKGROUND OF THE 1N~IENTION
[001] This is a continuation-in-part of application serial no. 10/176,808,
filed June 20, 2002.
1. Field of the invention
[002] This invention relates to bottom-hole assemblies used in oil and gas
wells, and more
particularly, to a check enhancer having .an outer -body with ports
longitudinally spaced from
ports in a dispersement nipple disposed in the outer body.
2. Description of the Prior Art
[003] It is well known in the production and treatment of oil and gas wells to
inject fluids into
the well. This is done in a variety of ways, one of which is to use a bottom-
hole assembly. Prior
art bottom-hole assemblies comprise a ball check valve attached to a ported
dispersernent nipple.
The ball check valve is connected to a length of coiled tubing by a known
tubing fitting. The
coiled tubing is used to run the tool into the well to a desired location. In
operation, fluid is
flowed down the tubing into the bottom-hole assembly. The fluid passes through
the ball check
valve which allows flow downwardly therethrough and prevenla any significant
amount of fluid
from flowing back upwardly tlu-ough the tubing. The fluid flows out of the
bottom-hole
assembly tlu-ough the ports in the dispersement nipple and into the well at a
location adjacent to
the bottom-hole assembly.
[004] These prior art bottom-hole assemblies have had a couple of problems.
First, scale
deposits due to contaminants in the well can build up in the ports in the
dispersement nipple, and
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this will eventually restrict the flow therethrough. If this occurs. it may be
necessary to remove
the assembly from the ~~ell prematurely for cleaning. This is both costly and
time consuming.
[005] Another problem mrith the prior art bottom-hole assembly is that bubbles
may form in the
dispersement nipple. These bubbles can float up within the dispersernent
nipple and pass
upwardly through the ball check valve, either when the ball check is open to
flow fluid
therethrough or because a complete seal may not be formed in the valve when it
is closed. These
bubbles can disrupt the flow through the tubing.
[006) The present invention solves these problems by adding an outer housing
around the
dispersement nipple of the prior art bottom-hole assembly. The body keeps
clean fluid around
the dispersement nipple which significantly reduces or eliminates scale
deposits in the check
valve and nipple ports. Also, the presence of fluid adjacent to the
dispersement nipple minimizes
bubble formation. Bubbles may form at the ports in the outer housing, but even
if this occurs,
the bubbles will merely float up to the upper inside portion of the outer
housing which is not a
problem because that portion of the housing is not,in communication with the
tubing.
SUMMARY OF THE INVENTION
[007) The present invention is an improved bottom-hole assembly; and more
specifically, as
used herein; a check enhancer apparatus for use in injecting fluids into a
well. The enhaneer
generally comprises a housing portion defining a fluid cavity therein and a
housing port in
communication with the fluid cavity, an injector portion connected to the
housing portion, and a
length of tubing connected to the injector portion. The injector portion
defines an injector port
therein in communication with the tubing and the fluid cavity, and the
injector port is
longitudinally spaced from the housing port.
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[008] The housing portion comprises an outer body in which the housing port is
disposed. The
injector portion comprises a dispersement nipple in which the injector port is
disposed and a
check valve connected to the dispersement nipple. At least the dispersement
nipple extends into
the fluid cavity.
[009] The check valve, preferably either a ball check valve or poppet-type
valve, allows fluid
flow from the tubing to the dispersement nipple and substantially prevents
fluid flow from the
dispersement nipple to the tubing. The housing port is preferably lacated
above the injector port
when the apparatus in disposed in the well, such that fluid flowing out of the
injector port at least
partially fills the fluid cavity before flowing out oi' the housing port. In
one embodiment, the
injector port is one of a plurality of injector ports, the housing port is one
of a plurality of
housing ports and all of the housing ports are longitudinally spaced from all
of the injector ports.
[010 Stated another way, the present invention is a check enhancer comprising
a dispersement
nipple defining a nipple port therein, a check valve connected to the
dispersement nipple and
adapted for connection to a length of tubing such that the nipple port is in
communication with
the tubing when the check valve is in an open position, and an outer body
disposed around the
dispersement nipple and defining a body port therein. The body port is
longitudinally spaced
from the nipple port, and in the preferred embodiment, the body port is above
the nipple port
when the apparatus is positioned in the well. The nipple port is preferably
one of a plurality of
nipple ports defined in the dispersement nipple, the body port is one of a
plurality of body ports
defined in the outer body, and all of the body ports are longitudinally spaced
from all of the
nipple ports. The check valve is attached to the tubing by a tubing fitting.
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[011] Numerous objects and advantages of the invention will become apparent as
the following
detailed description of the preferred embodiment is read in conjunction with
the drawings which
illustrate such embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[012] FIG. 1 shows a first embodiment of the check enhancer of the present
invention as it is
run into a well on a length of coiled tubing.
[013] FIGS. 2A and 2B illustrate a cross-sectional view of the first
embodiment of the
enhancer.
[014] FIGS. 3A and 3B is a cross-sectional view of a second embodiment of the
enhancer.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[O1S] Referring to FIG. 1. a first embodiment of the check emlzancer of the
present invention is
shown and generally designated by the nuzrzeral 10. Apparatus or enhancer 10
is shown
positioned in a well 12 on a length of coiled tubing 14.
[01b] Referring now also to FIGS. 2A and 2B, details of the first embodiment
of enhancer 10
will be discussed. Generally; ezW ancer 10 comprises an outer housing portion
16 and an inner
injector portion 18 disposed in the housing poz-tion. Injector portion 18 is
substantially the same
as a prior art check enhancer which has been used in wells without any outer
housing.
[017] Housing portion 16 includes an outer bod~r 20 and an adapter or bonnet
22 attached
thereto by any means known in the art, such as threaded connection 24. Adapter
22 defines a
central opening through which a portion of tubing 14 extends. Opening 26 is
sized so that tubing
14 may be slidably disposed therethrough.
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(018] Adapter 22 is attached to tubing 14 by a housing tubing fitting 28.
Housing tubing fitting
28 is connected to adapter 22 by any means know in the art; such as threaded
connection 30.
Housing tubing fitting 28 can be of any type known in the art; such as, but
not limited to. a
compression fitting as shown in FIG. 2A. Prior to tightening housing tubing
fitting 28, tubing 14
can be moved in opening 26 in adapter 22 so that injector portion 18 may be
placed in any
desired position relative to housing portion 16.
(019J In the embodiment shov~Jn in the draw-ings. outer body 20 comprises a
collar 32, a
cylinder 34 and an end cap 36: Collar 32 is fixedly attached to cylinder 34 by
a means known in
the art, such as a v~~eld 38. End cap 36 is fixedly attached to cylinder 34 by
a means knowm in the
art, such as weld 40. Thus; outer body 20 is integrally formed. Alternatively;
outer body.2~ may
be made from a single piece of material.
(020] Outer body 20 defines a fluid cavity 42 therein and a pluralit~.~ of
body or housing ports
44 ~~hich provide communication between fluid cavity 42 and well 12. Body
ports 44 are
preferably at the upper end of fluid cavity 42.
(021] Injector portion 18 includes a check valve 46 attached to a dispersement
nipple 48 by any
means know in the art. such as threaded connection 50.
(022] Check valve 46 includes a check valve body 52 having a first bore 54 and
a larger second
bore 56 therein. A downwla3-dly facing shoulder 58 extends betvreen first bare
54 and second
bore 56. . At an opposite end of second bore 56 is an upwardly facing shoulder
60 which
generally faces shoulder 58. A ball 62 is disposed in second bore 56 o.f check
valve body 52 and
is larger than fixst bore 54 so that the ball will seat on an edge 64 of
shoulder 58. Ball 62 is
biased toward shoulder 58 by a spring 66. It will be seen by those skilled in
the art that fluid can
pass downwardly through check valve 46, but upward flow is substantially
prevented.
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[023] Dispersement nipple 48 defines a bore 68 therein u~hicb is in
communication with cheek
valve 46. Bore 6$ is closed at its lower end. A plurality of nipple or
injector ports 70 is defined
in dispersement nipple 48. Nipple ports 70 provide communication between bore
68 and fluid
cavity 42 in outer body 20 when injector portion I8 is positioned in housing
portion 16. At the
lower end of dispersement nipple 48 is a tapered tip or nose 72 which helps
guide the
dispersement nipple as it is positioned in outer body 20.
[024] Check valve 46 is attached to tubing 14 by an injector tubing fitting
74. Injector tubing
fitting 74 is connected to check valve body 52 by any means know in the art,
such as threaded
connection 76. Injector tubing fitting 74 can be of any type know=n in the
art, such as, but not
limited to. a compression fitting as shown in FICi. 2B. After injector tubing
fitting is connected,
it will be seen by those skilled in the art that bore 68 and nipple ports ?0
are in communication
with tubing 14.
[025] During assembly of enhancer 10, check valve 46 is assembled and attached
to
dispersement nipple 48 as previously shown and described: Before or after
this, a portion of
tubing 14 is inserted through housing tubing fitting 28 and opening 26 in
adapter 22. Housing
tubing fitting 28 is not tightened at this point. Injector tubing fitting 74
is used to connect check
valve 46 to tubing 14 and tightened to make a complete injector portion 18.
Injector portion 18
is inserted into outer body 20. and the outer body is connected to adapter 22
as previously shown
and described. By moving tubing 14 through opening 26 in adapter 20, injector
portion l8 may
be positioned in the desired relative relationship within housing portion 16.
Housing tubing
fitting 28 is then tightened on tubing I4 to complete the assembly. It will be
seen by those
skilled in the art that nipple ports 70 are longitudinally spaced below body
ports 44 when
enhancer l0 is in an operating position in ulell 12. In a preferred
embodiment, injector portion
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18 is longitudinally positioned above end cap 36 such that scale and other
deposits will settle to
the bottom of fluid cavity 42 in housing portion 16 without interfering with
fluid flow from
nipple ports 70.
Second Embodiment
[02b] Referring now to FIGS. 3A and 3B, a second embodiment of the enhancer of
the present
invention is shown and designated by the numeral 100. Second embodiment
apparatus 100 is
connected to a length of tubing 102 as hereinafter described. Enhancer 100 is
positioned in a
~~ell on tubing 102 in a manner similar to first embodiment enhancer 10 on
tubing 14.
[027) Generally, enhancer 100 comprises a housing portion 104 and an injector
portion 106.
[028] Housing portion 104 includes an outer body 108 which itself comprises a
cylinder 110
znd an end cap 112. End cap 112 is fixedly attached to cylinder 110 by a means
known in the
art, such as weld 114.
[029] Outer body 108 defines a fluid cavity l 16 therein and a plurality of
body or housing ports
118 which provide communication between fluid cavity I 16 and the well. Body
ports 118 are
preferably at the upper end of fluid cavity 116.
[030) Injector portion 106 includes a check valve 120 connected to a
dispersement nipple 122
by an co~u~ector 124.
[03i] Check valve 120 includes a check valve body 126 connected to a check
valve cap 128 at
a threaded connection 130. Check valve body 126 defines a first bore 132 and a
larger second
bore 134 therein. A downrvardly facing sl-~oulder 136 extends between first
bore 132 and second
bore 134. At an opposite end of second bore 134 is an upwardly facing shoulder
138 which
generally faces shoulder 136. A ball 140 is disposed in second bore 134 of
check valve body
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126 and is larger than first bore 132 so that the ball will seat on an edge
142 of shoulder 136:
Ball 140 is biased tow%ard shoulder 136 by a spring 144. A third bore 146 is
defined in check
valve body 126 below shoulder 138. As further described herein, fluid can pass
downwardly
through check valve 120, but upward flow is substantially prevented.
[032] Check valve 120 is attached to connector 124 by any means known in the
art, such as
threaded connection 148. Cozv~ector 124 has an outer surface 150 which extends
into, and is
attached to, cylinder 110. This attaclmnent may be by a press fit, adhesives,
pinning, a threaded
correction or any other means known in the art. In a presently preferred
embodiment, cylinder
110 and connector 124 are attached by weld. Thus; it will be seen that
connector 124 provides a
aneans for connecting check valve 120 to outer body 108 of housing portion
104.
[033] Connector 124 defines a first bore 152 therein which is in communication
with check
valve 120 and a larger second bore 154.
[034] Dispersement nipple 122 extends into second bore 154 of connector 124.
Dispersement
nipple 122 and connector 124 are thus connected by a press fit, adhesives,
pinning, a threaded
correction or any other means known in the art. In a presently preferred
embodiment, nipple
122 and connector 124 are connected by weld.
[035] Dispersement nipple I22 defines a bore 156 therein which is in
communication with first
bore 1 S2 in connector 124 and thus with check valve 120. Bore 156 is closed
at its lower end. A
plurality of nipple or injector ports 158 is defined in dispersement nipple
122. Nipple ports 158
provide communication between bore 156 and fluid cavity 116 in outer body. At
the lower end
of dispersement nipple 122 is a tapered tip or nose 160 which helps guide the
dispersernent
nipple as it is positioned in outer body 108.
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[036 Check valve 120 is attached to tubing 102 by an injector tubing fitting
162. Injector
tubing fitting 162 is connected to check valve cap 128 by any means know in
the art, such as
threaded connection 164. Injector tubing fitting 162 can be of any t'rpe known
in the art, such as,
but not limited to, a compression fitting as shown in FIG. 3A. After injector
tubing fitting is
connected, it will be seen by, those skilled in the art that bore I 56 and
nipple ports 158 are in
communication with tubing 102.
(037] In the prefewed embodin gent, nipple ports 158 are longitudinally
positioned above end
cap 112 such that scale and other deposits will settle to the bottom of fluid
cavity I 16 in housing
portion 104 without interfering ~lith fluid flow from nipple ports I58. Also
in a preferred
ernbodin~ent. nose 160 of dispersement nipple 122 is attached by weld to end
cap 112.
Operation of the Invention
(038 In operation, first embodiment eWancer 10 is lowered into well 12 on
tubing 14 to the
desired depth and location in the well. Fluids are pumped down tubing 14 into
injector portion .
18. Check valve 46 allows fluid flow into dispersement nipple 48 and thus out
nipple ports 70
into fluid cavity 42 in housing portion I 6. The fluid flo~~~s upwardly
through fluid cavity 42 and
is discharged from enhancer 10 through body ports 44 into w-ell 12. Because
body ports 44 are
longitudinally spaced above nipple ports 70, fluid cavity 42 v~~ill always
have a volume of clean
fluid in it from the tubing. That is, dispersenaent nipple 48 is at least
partially submerged in this
clean fluid which substantially minimizes ox eliminates the build up of scale
deposits in nipple
ports 70. As previously mentioned; such scale deposition and the undesirable
restriction in fluid
flow resulting therefrom are problems with prior art enhancers w-hich are
solved by the present
invention. Scale deposits may form in body ports 44, but this is not a problem
because these
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ports aresubstantially larger than nipple ports 70 and no significant
reduction in fluid flow.
occurs.
[039) In the operation of second embodiment enhancer 100, it is lowered into a
»~ell on tubing
102 to the desired depth and location in the same manner as first embodiment
enhancer 10.
Fluids are pumped down tubing l02 into injector portion 106. Check valve 120
allows fluid
flow into dispersement nipple 122 and thus out nipple ports 158 into fluid
cavity 116 in housing
portion 104. The fluid flov~rs upwardly through fluid cavity 116 and is
discharged from enhancer
100 tlu-ough body ports I18 into the well. Because body ports I18 are
longitudinally, spaced
above nipple ports 158, fluid cavity I16 will always have a volume of clean
fluid in it from the
tubing. That is, dispersement nipple 122 is at least partially submerged in
this clean fluid which
substantially minimizes or eliminates the build up of scale deposits in nipple
ports 158. Scale
deposits may form in body ports I18, but this is not a problem because these
pours are
substantially larger than nipple ports 158 and no significant reduction in
fluid flow occurs.
[040) In either embodiment. the creation of undesirable bubbles in
dispersement nipple 48 or
122 is minimized or eliminated because it is submerged. Any bubbles will form
instead in fluid
cavity 42 or 116 and float to the top thereof This is not a problem because it
is virtually
irnpossihle for these bubbles to enter tubing 14 or 102.
[041] It will be seen, therefore. that the check eWancer of the present
invention is »ell adapted
to carry out the ends and advantages mentioned, as well as those inherent
therein. ~~Jhile two
presently preferred embodiments have been slzov,~n for the purposes of this
disclosure, numerous
changes in the arrangement and construction of parts may be made by those
skilled in the art.
All such changes are encompassed within the scope and spirit of the appended
claims.
[042] Vv~hat is claimed is:
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