Note: Descriptions are shown in the official language in which they were submitted.
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PLUNGER LIFT LUBRICATOR
BACKGROUND
[0001] This section provides background information to facilitate a better
understanding of the
various aspects of the disclosure. It should be understood that the statements
in this section of
this document are to be read in this light, and not as admissions of prior
art.
[0002] Hydrocarbon producing gas wells generally produce liquids in addition
to the flowing gas
stream. These fluids, gas and liquids, are conducted to the surface by a
string of production
tubing that communicates the below ground formation to piping system at the
surface. Removal
of the liquid fraction of the fluid column is mandatory for maintaining the
unrestricted
production of gas from the production zone formation. Frequently, a beam pump
unit is
employed for this task. However, beam pumping units are expensive and suffer
from high
maintenance costs.
[0003] In the field of plunger lift, a plunger acts as an unattached free-
traveling piston within the
length of the production tubing for the purpose of lifting liquids from an
active, gaseous
hydrocarbon-bearing formation. In the life cycle of a plunger lift system, the
plunger travels first
downwardly to the bottom region of the tubing string adjacent to the formation
then upwardly
within the tubing string multiple times within the course of the day. The use
of a plunger within
the tubing conduit of a gas well will enable the upward flow of light-density
gas to push toward
the surface those heavier liquids within the tubing string.
[0004] The tenn wellhead lubricator can refer to the sealing and packing
device atop the
wellhead of a rod pumping unit where the polish rod enters the wellbore at the
surface. In the
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field of plunger lift, a housing unit mounted atop a flowing gas well is also
referred to as a
lubricator. The plunger lift lubricators extant are occasionally made as a
single outlet version in
a T-shaped arrangement wherein production fluids flow into the T-shaped
lubricator and thence
into the surface piping. The upwardly traveling plunger moves into the
uppeiniost portion of this
T-shaped lubricator and held in this uppermost position by the up-flowing gas
stream. When the
moving gas stream is telininated by the subsequent closure of a valve within
the surface piping
downstream of the lubricator, the plunger falls into the wellbore by the force
of gravity.
[0005] In a more common iteration, the common plunger lift lubricator is
referred to as a "dual
outlet," meaning that the lubricator has two production passageways extending
perpendicular
from the main vertical section. An example of a common lubricator 300, having
dual outlets, is
illustrated in Figure 1. The common lubricator 300 includes a metal vertical
flow body 302
having an uppermost end 304 and a lowermost end 306, which are threaded (e.g.,
2-3/8 inch 8-
round thread). A spring housing 308 is threaded connected at the uppermost end
304. The two
outlets 310, 312 do not define a cross but instead are located one above the
other along the length
of the vertical flow body of the lubricator 300 and are separated vertically
by the approximate
length of a common plunger (piston). The purpose of the dual outlet
arrangement is to avoid
flow restrictions as the plunger enters into and remains in the lubricator
vertical section. A
single outlet lubricator is subject to flow restrictions, should the plunger
come to rest across the
opening of the single outlet.
[0006] The lowermost end of the common lubricator, made from metallic tubing,
presents a seal-
tight threaded arrangement for attachment to the wellhead. In a common
alternate version, the
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lowermost end of the common lubricator is first attached, by threading or
welding, to a flange
which is subsequently bolted to the mating flange of the uppermost valve in
the wellhead. All
common flanges are purchased as pre-threaded or as prepared for welded
attachment. Welded
connections are capable of holding 10,000 psi.
[0007] In general, the uppermost section of the common wellhead assembly
(e.g., tree) that
exists below these common lubricators presents a flange style connection as
the preferred version
within the industry because of the reliability and pressure holding
capabilities of flange
connections. Flange to flange connections are capable of holding 10,000 psi.
[0008] The outlet pipe connections 311, 313 oriented horizontally and attached
to the vertical
section of the common lubricator are made by the use of seal-tight threaded
connections (2"
NPT) or with the aid of the welding process. The connections, whether threaded
or flanged,
joining the lowermost section of these common lubricators to the uppermost end
of the wellhead
tree are made using seal-tight threaded components or with the aid of the
welding process to join
the metallic tubing to the flange on the lowermost end of the common
lubricator.
[0009] The one or more threaded (2" NPT) connectors 311, 313 (thread-o--lets)
of the common
lubricator 300 that are provided at the respective one or more outlets 310,
312 are attached to the
vertical section by welding 315. This threaded adaptor 311, 313, welded to the
vertical section,
permits threaded piping to be connected. All appropriate passageways 310, 312
are first drilled
into the vertical section prior to the welding process. In another common
iteration, one or more
horizontally oriented flanged style outlet connectors may be used and are
welded to the vertical
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section of the common lubricator and later joined to the surface pipe facility
by mating to these
flanged connections.
[0010] For the purpose of inspecting or removing the plunger, a catcher device
316 is installed
with the lubricator 300 to catch and hold the plunger in its uppermost
position within the
lubricator. This device is most commonly a spring-loaded pin that passes
horizontally through
the external wall of the lubricator and acts to pin the plunger against the
opposite wall. The
rounded end of the pin that makes contact with the plunger does not damage,
nor is damaged, by
impact with the plunger.
[0011] Limitations of the common plunger lift lubricators extant include the
use of the various
threaded connections. The commonly used threaded pipe, National Pipe Thread
("NPT"),
specifications describe a V-shape thread with a pressure containment rating of
5,000 psi (2"
NPT), whereas the wellhead tree is commonly rated at 10,000 psi. Dissimilar
ratings invite
mistakes with potential for failure. A pressure-caused failure can occur when
a fracking
operation is being conducted on a nearby wellbore and the fractures migrate
through the
hydrocarbon-containing source-rock to a wellbore that has been completed by
underrated surface
equipment, including a lubricator with NPT, V-shaped threads.
[0012] Another limitation related to the use of a common lubricator involves
failures related to
misalignment in the several components of the piping arrangement leading away
from the
wellhead and lubricator assembly. The equipment and components that make up
the totality of
the wellhead and surface facilities is supplied by a variety of vendors. This
variety of equipment
is typically installed by third parties without complete knowledge of any
limitations that should
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signal against alignment by force. Forced alignment procedures can be the
source of failures in
piping systems under cold stress. By its nature, threaded pipe is rigid and
unforgiving with
regard to misalignment. The exposed threaded section of threaded pipe
represents the weakest
point along the length of the pressure-containing pipe and the most common
location for stress
cracking and failure.
[0013] Further limitations are related to the use of welded connections. The
welding process
creates a heat affected zone ("HAZ") adjacent to the weld. The improper
heating and cooling of
this heat affected zone creates internal stress within the material.
[0014] With or without the heat of the welding process, the materials of these
pressure
containing lubricators are aggravated by a cold environment.
Steel, when subject to
temperatures for example below zero-degrees Fahrenheit, becomes brittle. It is
common for
lubricators used in cold climates to experience stress-inducing temperature
swings from 100 to -
20 degrees Fahrenheit in a matter of minutes, multiple times a day, from the
intermittent flow of
very warm production fluids in the presence of sub-zero wind and blowing snow.
SUMMARY
[0015] A plunger lift lubricator including a lower lubricator section having
an internal lubricator
bore extending axially from a top thread profile to a bottom flange profile an
outlet pipe
connector comprising a body having a vertical throughbore forming a portion of
the lubricator
bore and a radial passage extending through a pipe connector profile to the
vertical throughbore.
In accordance to aspects of the disclosure the lower lubricator section does
not have any welds.
In some embodiments the lower lubricator section is formed of a single piece
of material
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including the top thread profile, the bottom flange profile, and the outlet
pipe connector and the
pipe connector profile.
[0016] In some embodiments the lower lubricator section includes the outlet
pipe connector
formed of a single piece of material with the vertical throughbore extending
between a top
surface and a bottom surface, a flow body formed of a single piece of material
having a vertical
throughbore forming a portion of the lubricator bore and extending from the
bottom flange
profile to a top flange profile that is connected to the bottom surface of the
outlet pipe connector
and an adaptor formed of a single piece of material having a vertical
throughbore forming a
portion of the lubricator bore extending from the top thread profile to a
bottom flange profile that
is connected to the top surface of the outlet pipe connector.
[0017] This summary is provided to introduce a selection of concepts that are
further described
below in the detailed description. This summary is not intended to identify
key or essential
features of the claimed subject matter, nor is it intended to be used as an
aid in limiting the scope
of claimed subject matter.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The disclosure is best understood from the following detailed
description when read with
the accompanying figures. It is emphasized that, in accordance with standard
practice in the
industry, various features are not drawn to scale. In fact, the dimensions of
various features may
be arbitrarily increased or reduced for clarity of discussion.
[0019] Figure 1 illustrates a prior art common plunger lift lubricator.
[0020] Figure 2 illustrates a plunger lift well system incorporating a
lubricator in accordance
with one or more aspects of the disclosure.
[0021] Figure 3 illustrates a plunger lift lubricator having a lower
lubricator section that is
constructed of a single piece of material including the top and bottom
connection profiles and
one or more outlet pipe connectors in accordance with aspects of the
disclosure.
[0022] Figure 4 illustrates a single piece lower lubricator section including
the top and bottom
connection profiles and more than one outlet pipe connector according to
aspects of the
disclosure.
[0023] Figures 5 and 6 illustrate a single piece lower lubricator section
including the top and
bottom connection profiles and a single outlet pipe connector according to
aspects of the
disclosure.
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[0024] Figure 7 illustrates a plunger lift lubricator having a lower
lubricator section that is
constructed of multiple elements interconnected without welding in accordance
with one or more
aspects of the disclosure.
[0025] Figures 8 and 9 illustrate an example of a multiple element lower
lubricator section
according to aspects of the disclosure including a bore liner.
[0026] Figure 10 illustrates an example of a plunger catcher in accordance to
one or more
aspects of the disclosure.
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DETAILED DESCRIPTION
[0027] It is to be understood that the following disclosure provides many
different embodiments,
or examples, for implementing different features of various embodiments.
Specific examples of
components and arrangements are described below to simplify the disclosure.
These are, of
course, merely examples and are not intended to be limiting. In addition, the
disclosure may
repeat reference numerals and/or letters in the various examples. This
repetition is for the
purpose of simplicity and clarity and does not in itself dictate a
relationship between the various
embodiments and/or configurations discussed.
[0028] As used herein, the terms connect, connection, connected, in connection
with, and
connecting may be used to mean in direct connection with or in connection with
via one or more
elements. Similarly, the terms couple, coupling, coupled, coupled together,
and coupled with
may be used to mean directly coupled together or coupled together via one or
more elements.
Terms such as up, down, top and bottom and other like terms indicating
relative positions to a
given point or element are may be utilized to more clearly describe some
elements. Commonly,
these terms relate to a reference point such as the surface from which
drilling operations are
initiated.
[0029] With reference generally to Figures 2 to 10 example embodiments of
lubricators for use
in plunger lift systems are described. Figure 2 illustrates a well system 5
incorporating a plunger
lift system 7 in accordance to one or more aspects of the disclosure. Plunger
lift system 7
includes a lubricator 10 in accordance to one or more aspects of the
disclosure positioned at the
top of a production string 12 (tubing string) to cushion the arrival of a
plunger 14 (i.e., piston)
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that cyclically travels a length of the production string 12. Plunger 14 may
be a bypass or a solid
plunger. The depicted plunger 14 is illustrated as a bypass type of plunger
having an internal
passage that is selectively blocked by a valve element 16 (e.g., ball, dart,
etc.).
[0030] The lubricator 10 is a special piping arrangement installed for plunger
lift to capture the
cycling plunger 14 at the top of the well. In accordance to embodiments the
lubricator 10
includes an arrival spring 18 (mechanical or gas), which cushions the arrival
of a plunger within
the lubricator 10, and one or more radial fluid outlets 20 each formed in an
associated outlet pipe
connector 22 to connect the lubricator to the surface production pipe 24. The
lubricator 10 may
include one or more catchers 26 adapted to selectively hold the plunger 14
within the lubricator.
In accordance to some embodiments the catcher may be arranged with an outlet
pipe connector.
[0031] The well system 5 includes a borehole 28 extending from a surface 30 of
the earth to a
producing formation 32. Wellbore 28 may be lined with a casing 34 including
perforations 36
proximate the producing formation. The surface end of the casing is closed at
the surface by a
wellhead generally denoted by the numeral 38 having a valve 40 located below
or upstream of
the lubricator toward the producing formation. The production string 12
extends down the
wellbore inside of the casing. A bumper spring 42 is positioned at the lower
end of the tubing
string 12 to stop the downward travel of the plunger 14.
[0032] Formation fluid 44 enters the casing through the perforations and into
the tubing string
for example through a standing valve 46. The free travelling plunger 14 is
lifted from the bottom
of the well to the surface when the lifting gas energy below the plunger is
greater than the liquid
load 48 and gas pressure above the plunger. In a plunger lift system
operation, the well is shut-in
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by closing for example a flow control valve 25 for a period of time during
which sufficient
formation pressure is developed within the casing to move the plunger 14 and
the liquid slug 48
that is above the plunger upward to the surface when the flow control valve is
opened.
[0033] With reference in particular to Figures 2-10, the plunger lift
lubricator 10 generally
includes a lower vertical lubricator section 11 forming a vertical bore 54 and
extending between
a top end 56 connected to a spring housing 52 carrying the arrival spring 18
and a bottom end 58
to be connected to a wellhead. The lower vertical section comprises a flow
body 50 and a radial
outlet 20 formed in a pipe connector 22. According to aspects of the
disclosure the lower
lubricator section 11 does not include welded connections. Figures 3-6
illustrate a lower
lubricator section 11 that is constructed, via forging or machining, as a
single piece including the
top and bottom connection profiles 56, 58 and the one or more outlet pipe
connectors 22.
Figures 7-9 illustrate embodiments of a lower lubricator section 11 formed of
interconnected
elements without welding. Figure 10 illustrates a non-limiting example of a
catcher 26.
[0034] Referring first to Figures 3-6, the spring housing 52 is connected to
the top end 56 of the
flow body via threading to allow for removal of the spring housing when
needed. The bottom
end 58 is adapted to connect to the wellhead. Each of the flow bodies 50
illustrated in Figures 3-
6 have a flange type profile at the lowermost end 58 for connecting with the
wellhead, however,
a threaded connection may be utilized. In accordance to some embodiments, the
lowermost end
58 is machined, forged, or cast with the flange profile to avoid the weakness
of welding a flange
profile onto the flow body.
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[0035] The flow body 50 includes one or more radial production outlets 20.
Each outlet 20 is
formed through an outlet pipe connector 22 which is formed as a single unit
with the flow body
50 in Figures 3-6. The pipe connector 22 forms a horizontal passage 66
extending from the
radial outlet 20 and lubricator bore 54 through a pipe connector profile 68
for connecting to the
surface production piping 24 (Figure 2). In Figures 3 and 4 the pipe connector
profile 68 is a
thread profile. In accordance to some embodiments, the thread profile 68 is an
Acme thread
profile, such as a 14.5 degree thread profile. In Figures 5 and 6 the
connector profile 68 is a
flange profile. The outlet pipe connector 22 is forged, machined or cast with
the flow body 50
eliminating the welded connection of a thread or flange connector profile 68.
[0036] In accordance to some embodiments, the outlet pipe connector 22
includes a catcher 26
for example as described below with particular reference to Figure 10. In the
non-limiting
illustrated embodiments, the catcher 26 is aligned for example 180 degrees
from the horizontal
passage 66.
[0037] With reference in particular to Figures 3-6, the flow body 50 is
machined, forged or cast
as a one-piece unit including the outlet pipe connector(s) 22 and the
connection profiles on the
terminal ends 56, 58 from a single piece (billet) of material. The flow body
50 may be
constructed for example of an alloy compound including but not limited to
carbon, stainless
steel, or other corrosion resistant materials. In accordance to an embodiment
a billet of material
receives a stress-relieving heat-treatment from the supplying mill at the time
of manufacture and
carries a Rockwell hardness rating of 22 or less (Rc22). Above 22Rc, steel
will not pass the
Charpy impact test and is deemed unsuitable for cold service.
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[0038] The lubricator bore 54 may include one or more internal diameters. For
example, in
Figures 3-6 the lubricator bore 54 comprises a top passage 70 portion
proximate to the top end
56 having a different diameter than a lower passage 72 portion extending below
the top passage
portion. In the illustrated embodiments, the top passage 70 has a larger
diameter than the lower
passage 72. With reference to Figure 3, the lower end 74 of the spring housing
52 is positioned
inside the top passage 70 and an internally threaded collar 76, which is
rotationally attached to
the spring housing 52, connects with the external threads on the top end 56 of
the flow body 50.
A seal (e.g., 0-ring) 78 is disposed with the lower end 74 of the spring
housing to seal the
connection with the flow body and lubricator bore. The addition of seal 78
provides for
additional sealing capability in particular in the event that the spring
housing 52 and flow body
50 are misaligned during connection. A striker element 80 may be disposed with
the arrival
spring 18 and located at least partially within the top passage 70 portion of
the flow body. The
illustrated striker element 80 is a striker block for use for example with a
plunger having a male
fish neck profile. The striker element 80 can take various forms. In some
embodiments the
striker element 80 will include a rod to extend into the internal passage of
the plunger to move
the valve element to the open position.
[0039] In the illustrated embodiments the uppermost end 56 is defined by a
thread profile
without the aid of the welding process. The thread profile of the uppermost
end 56 conforms to a
14.5 degree Acme profile in at least one embodiment, representing a strong,
pressure resistant
design, unlike the common V-thread. In accordance to some embodiments, the
thread profile of
the outlet pipe connector profile 68 conforms to a 14.5 degree profile to
maintain the integrity of
the seal by withstanding the pressure induced stress.
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[0040] Square threads have a zero-degree thread flank angle and induce less
friction than a 14.5
degree Acme profile and therefore may be preferred for maximal applied axial
force to engage
the sealing element into a leak-tight joint. However, the square thread
profile is subject to
loosening, especially in the presence of the type of vibration that occurs
periodically within a
flowing fluid stream that is intermittently pressurized with gas then liquid.
In accordance with
an embodiment a square thread may be utilized with an anti-rotation, thread
locking device to
secure a non-locking, square thread.
[0041] Common 60 degree V-threads, whether straight or tapered, induce undue
friction during
the tightening process because the vector of the thread angle directs 30% of
the force generated
during the tightening process in a direction perpendicular to the preferred
axis. Consequently,
the common, 60 degree V-thread may not impart sufficient axial force to engage
the mating
surfaces of the surface piping into the concave surface of the lubricator
outlet profile. The
common V-thread is defined by its seal-tight thread. In profile, the thread is
tapered along its
length which causes the male profile to wedge into the female profile as the
threads are
tightened. For the pressurized fluid to escape it must migrate the length of
the spiral path of the
thread engagement, a task made difficult by the presence of the sealant
compound. The Acme
thread taught herein is a straight thread in profile wherein the spiral
profile maintains a constant
diameter along its length. Sealing does not take place within the thread
itself. The seal occurs
when the engagement of the thread acts to bias two mating surfaces into a
sealing contact. These
two surfaces are each defined by a radius shape, one concave and the other
convex, hence, the
allowance for a slight misalignment. The 14.5 degree thread profile carries a
greater sheer
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resistance because the profile of the thread is wider at its base when
compared to a square thread
profile.
[0042] Acme threads (14.5 degree) are considerably stronger against the forces
of thrust versus
V-thread. At 14.5 degrees, the Acme thread flank profile combines the correct
balance of thread-
locking friction with the ultimate holding power of the material's yield
strength. This
combination resists the axial movement generated by the force of the internal
pressure as well as
resistance to rotational creep.
[0043] Referring now to Figures 7-9, the lubricator 10 includes a lower
lubricator section 11
formed of multiple elements that are interconnected without welding. In the
illustrated
embodiments, the vertical lubricator bore 54 of the lower lubricator section
11 is formed of a
flow body 50 having the bottom connector profile 58, one or more outlet pipe
connectors 22, and
an adaptor 60 carrying the top connector profile 56 for connection with a
spring housing 52. In
the illustrated embodiments the lower lubricator elements 50, 22, 60 are
interconnected at non-
threaded flanges. In Figure 7 a portion of the lubricator bore 54 adjacent to
the radial outlet 20 is
shown with an enlarged diameter relative to the bore 54 at the bottom end 58
to dispose a liner as
illustrated in Figures 8 and 9. Although all of the single outlet lubricators
are shown as including
a liner as further described below, the single outlet lubricators do not
require a liner.
[0044] The outlet pipe connector 22 comprises a body 62 formed of a single
piece of material
such as an alloy compound including but not limited to carbon, stainless
steel, or other corrosion
resistant materials. In accordance to an embodiment a billet of material
receives a stress-
relieving heat-treatment from the supplying mill at the time of manufacture
and carries a
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Rockwell hardness rating of 22 or less (Rc22). Above 22Rc, steel will not pass
the Charpy
impact test and is deemed unsuitable for cold service. In the illustrated
examples the outlet pipe
connector is formed from a square shaped raw material and may retain the
square shape when
completed.
[0045] The outlet pipe connector 22 comprises a vertical throughbore 64
forming part of the
lubricator bore 54 and extending between top and bottom surfaces 82, 84 or
flange profiles. A
horizontal passage 66 extends radially from vertical throughbore 64 to a
surface pipe connection
profile 68 for connection with the surface piping 24 (Figure 2). The surface
pipe connection
profile 68 may be a threaded or flange type of profile. In accordance to
embodiments the flange
profiles 68, 82, 84 may be the planar or substantially planar outer surface of
the outlet pipe
connector 22. In the illustrated examples, the flange profiles of the outlet
pipe connector 22 may
include threaded sockets 90 for receive threaded elements (e.g., studs or
bolts) 92 or may
comprise threaded elements 92 on which the flange profiles of the respective
adaptor 60, flow
body 50 and surface piping can be attached. In accordance to some embodiments,
the outlet pipe
connector 22 includes a catcher 26 for example as described below with
particular reference to
Figure 10. In the non-limiting illustrated embodiments, the catcher 26 is
aligned for example
180 degrees from the horizontal passage 66.
[0046] The flow body 50 is made as a one-piece unit, machined, forged or cast
from a single
piece of material, along a single vertical axis of a material such as used to
form the outlet pipe
connector 22. The lower end 58 of the flow body 50 is formed with a connection
profile adapted
for connecting with a wellhead. In the illustrated examples the lower end
profile 58 is a flange
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profile. The flow body 50 has a top flange-type connection profile 86 for
connection with the
bottom flange-type connection profile 84 of the outlet pipe connector 22. The
flow body 50 has
a vertical throughbore 65 forming part of the lubricator bore 54 and extending
from the bottom
end 58 to the top end 86.
[0047] Adaptor 60 is made as a one-piece unit, machined, forged or cast from a
single piece of
material, of a material such as used to form the outlet pipe connector 22 and
flow body 50.
Adaptor 60 has a vertical throughbore 67 extending from the top end 56 to the
bottom flange-
type connection profile 88 connected to the top flange connection profile 82
of the outlet pipe
connector 22. In accordance to some embodiments, the top threaded profile 56
and or a threaded
connector profile 68 conforms to a 14.5 degree Acme profile in at least one
embodiment,
representing a strong, pressure resistant design, unlike the common V-thread.
[0048] With reference to Figures 2-10, the lower lubricator section 11 may
include one or more
horizontally oriented pipe outlets 20. Two or more outlets 20 are
traditionally utilized to reduce
or remove the possibility of the plunger 14 from blocking the flow path of the
produced fluid
from the production string through the lubricator and into the surface piping.
If the plunger
blocks a first horizontal outlet 20 the wellbore fluid can be produced from
one or more of the
additional vertically spaced horizontal outlets 20.
[0049] Relative to a multiple outlet lubricator, a single outlet reduces the
cost of manufacturing
and the costs in the related surface piping. To remove or reduce the
possibility of the traveling
plunger 14 blocking the flow path of the up-flowing fluid from within the
wellbore, the single
outlet 20 lubricator may comprise an annular passageway 94 that allows the
wellbore fluid to
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bypass the plunger 14 within the lubricator to pass through the outlet 20 into
the surface piping
as illustrated for example in Figures 3, 6, and 8-10. In accordance to
embodiments, the annular
passage 94 is formed between a perforated liner 96 disposed in the lubricator
bore 54 adjacent to
the outlet 20 and the inner wall 98 forming the lubricator bore. The
perforated liner 96 includes
openings 100 to allow fluid to pass radially through the liner. In accordance
to some
embodiments, an opening 100 may be sized and positioned to pass a pin element
of a catcher 26,
see e.g. Figure 10.
[0050] Figure 10 illustrates an example of a catcher 26 which may be utilized
with a lubricator
section 11. Catcher 26 includes an element 102, such as pin, adapted to
selectively engage a
plunger 14 (e.g., Figure 8) when it is located in the lubricator bore 54. In
the illustrated example
the pin 102 is biased by a spring 104. In accordance to some embodiments the
catcher 26 is
automated and operated by an actuator. Pin 102 is moveably disposed in a
radial passage 106
formed for example through the outlet pipe connector 22 and extending from the
outer surface 63
to the lubricator bore 54. In accordance to some embodiments, the pin passage
106 is located
about 180 degrees from the horizontal outlet passage 66. An end piece 108 is
connected with the
body 62 of the outlet pipe connector 22 over the pin passage 106. In the
illustrated example, the
end piece 108 is connected with a non-welded fastener 110, e.g., a screw, to
avoid a welded
connection. The end piece may be connected via welding in some embodiments.
[0051] The foregoing outlines features of several embodiments so that those
skilled in the art
may better understand the aspects of the disclosure. Those skilled in the art
should appreciate
that they may readily use the disclosure as a basis for designing or modifying
other processes and
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structures for carrying out the same purposes and/or achieving the same
advantages of the
embodiments introduced herein. Those skilled in the art should also realize
that such equivalent
constructions do not depart from the spirit and scope of the disclosure, and
that they may make
various changes, substitutions and alterations herein without departing from
the spirit and scope
of the disclosure. The scope of the invention should be determined only by the
language of the
claims that follow. The term "comprising" within the claims is intended to
mean "including at
least" such that the recited listing of elements in a claim are an open group.
The terms "a," "an"
and other singular terms are intended to include the plural forms thereof
unless specifically
excluded.
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