U.S. patent application number 17/327862 was filed with the patent office on 2021-12-02 for quick connect device for fractrap and method.
The applicant listed for this patent is GEODYNAMICS, INC.. Invention is credited to Jeremy Eli CASTANEDA, Kevin GEORGE, Raymond Christopher SHAFFER.
Application Number | 20210372206 17/327862 |
Document ID | / |
Family ID | 1000005623747 |
Filed Date | 2021-12-02 |
United States Patent
Application |
20210372206 |
Kind Code |
A1 |
SHAFFER; Raymond Christopher ;
et al. |
December 2, 2021 |
QUICK CONNECT DEVICE FOR FRACTRAP AND METHOD
Abstract
A quick connect device for connecting a plug to a setting tool
includes a collet having a body and plural fingers; a first end of
the collet is configured to be attached to a trapping mechanism
associated with the setting tool; and a second end of the collet
has the plural fingers, which are configured to be attached to the
plug. The second end automatically connects to the plug by only
pushing the second end onto the plug.
Inventors: |
SHAFFER; Raymond Christopher;
(Burleson, TX) ; CASTANEDA; Jeremy Eli;
(Weatherford, TX) ; GEORGE; Kevin; (Cleburne,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GEODYNAMICS, INC. |
Millsap |
TX |
US |
|
|
Family ID: |
1000005623747 |
Appl. No.: |
17/327862 |
Filed: |
May 24, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
63031820 |
May 29, 2020 |
|
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|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 23/06 20130101;
E21B 17/046 20130101; E21B 17/0423 20130101 |
International
Class: |
E21B 17/046 20060101
E21B017/046; E21B 17/042 20060101 E21B017/042; E21B 23/06 20060101
E21B023/06 |
Claims
1. A quick connect device for connecting a plug to a setting tool,
the quick connect device comprising: a collet having a body and
plural fingers; a first end of the collet is configured to be
attached to a trapping mechanism associated with the setting tool;
and a second end of the collet has the plural fingers, which are
configured to be attached to the plug, wherein the second end
automatically connects to the plug by only pushing the second end
onto the plug.
2. The quick connect device of claim 1, wherein each finger of the
plural fingers engages a ring located on the plug.
3. The quick connect device of claim 2, wherein each finger has a
tab which is configured to move past the ring and lock the tab onto
the ring.
4. The quick connect device of claim 3, wherein at least one finger
of the plural fingers has an extension that extends past the
corresponding tab.
5. The quick connect device of claim 2, wherein at least one finger
of the plural fingers is longer than the plural fingers.
6. The quick connect device of claim 1, wherein the collet is
attached with threads to the trapping mechanism.
7. The quick connect device of claim 6, wherein the trapping
mechanism is attached with threads to the internal sleeve of the
setting tool.
8. The quick connect device of claim 1, wherein the collet, the
trapping mechanism, and the plug fluidly communicate with each
other and a ball is sized to pass through the collet, from the plug
to the trapping mechanism.
9. The quick connect device of claim 8, further comprising: the
ball, wherein the ball is sized to not pass through an internal
bore of the plug and the trapping mechanism is configured to trap
the ball to prevent the ball from returning to the plug.
10. A system for connecting a plug to a setting tool with a quick
connect device, the system comprising: the plug, which is
configured to seal a bore of a casing in a well; and the quick
connect device, wherein the quick connect device has a collet that
automatically engages and locks onto the plug by only pushing the
collet onto the plug.
11. The system of claim 10, further comprising: a trapping
mechanism configured to be attached to an internal sleeve of the
setting tool; and an external sleeve configured to house the
trapping mechanism and the quick connect device, wherein the collet
is configured to be attached with a first end to the trapping
mechanism and with a second end to the plug.
12. The system of claim 10, wherein the plug has a mandrel and a
ring located on the mandrel.
13. The system of claim 12, wherein the collet has plural fingers
at the second end, and each finger engages the ring located on the
mandrel.
14. The system of claim 13, wherein each finger has a tab which is
configured to move past the ring and lock the tab onto the
ring.
15. The system of claim 12, wherein the ring is configured to break
at a desired force, to free the quick connect device from the
plug.
16. The system of claim 12, wherein the ring is molded into a
mandrel of the plug.
17. The system of claim 12, wherein the ring is placed into a
trench formed in a mandrel of the plug.
18. The system of claim 13, wherein at least one finger of the
plural fingers has an extension that extends past the corresponding
tab.
19. The system of claim 11, further comprising: a ball, wherein the
trapping mechanism has an internal chamber configured to hold the
ball and the ball is sized to pass through an internal bore of the
collet.
20. A method for connecting a plug to a setting tool before being
deployed in a well, the method comprising: providing a plug having
a mandrel, the mandrel having a ring that extends around and away
from the mandrel; attaching a trapping mechanism to a collet;
attaching the collet to the ring of the plug by only pushing the
collet onto the plug; sliding the trapping mechanism, while
connected to the collet and the plug, inside an external sleeve of
a setting kit; and rotating the plug to attach threads of the
trapping mechanism to an internal sleeve of the setting tool.
Description
BACKGROUND
Technical Field
[0001] Embodiments of the subject matter disclosed herein generally
relate to a quick connect device that is used in a well for setting
a plug, and more specifically, to a setting tool having a ball trap
that is modified with the quick connect device to attach without
screws to the plug for setting the plug in the well.
Discussion of the Background
[0002] After a well is drilled and cased, a fluid connection needs
to be established between the bore of the casing and the formations
outside the well. One or more perforation guns are used for this
purpose, i.e., to make holes through the casing to establish the
fluid connection between the bore and the formations. The
perforation guns may be lowered into the well together with a
setting tool, a plug, and a corresponding ball, which is shaped to
seal a bore of the plug. The setting tool sets the plug at a
desired level inside the well, the ball is moved into the bore of
the plug to seal it, and then the perforating guns are fired to
establish perforations into the casing, i.e., to achieve the fluid
connection between the bore of the casing and the formations. A
fracturing fluid is then pumped into the well and into the
formations, through the perforations, to fracture the formations.
Because of the plug and the ball that seals the bore of the plug,
the fracturing fluid is forced through the perforations only in the
current stage.
[0003] A typical setting tool/plug system 100 is illustrated in
FIG. 1A and includes the setting tool 110 and the plug 130 and a
setting kit 120 that connects the setting tool to the plug. The
setting kit 120 includes, among other components, an internal
sleeve 112 and an external sleeve 114, that encloses the internal
sleeve 112. The plug 130 has a mandrel 132 that defines a bore 134.
Various elements are distributed along the mandrel 132, for
example, a top push ring 136, an upper slip ring 138, an upper
wedge 140, a sealing element 142, a lower wedge 144, a lower slip
ring 146, a bottom push ring 148, and a mule shoe 150. The top push
ring 136 becomes in direct contact with the external sleeve 114
while the bottom push ring 148 is attached with screws 149 to the
internal sleeve 112. When the setting tool is activated, the
external sleeve presses through the external sleeve 114 of the
setting kit against the top push ring while the internal sleeve of
the setting tool holds still the bottom push ring, through the
internal sleeve of the setting kit. The setting tool is typically
activated by an explosive charge that causes a piston to be driven
inside the setting tool. The movement of this piston is used for
sliding one of the internal sleeve or the external sleeve relative
to the other sleeve.
[0004] This opposite motion of the internal and external sleeves
112 and 114 makes the wedges 140 and 144 to push away, radially,
the slip rings 138 and 146, to engage the casing (not shown) of the
well while also compressing the sealing element 142. This motion
results in the slip rings pressing strongly against the casing,
which prevents, due to the high friction, the entire plug from
slipping relative to the casing, and also results in the sealing
element sealing the bore of the casing, and thus preventing a fluid
from moving past the plug.
[0005] After the plug has been set, the internal sleeve of the
setting kit breaks out from the bottom push ring and thus, the
setting tool and the setting kit detaches from the plug, so that
the setting tool together with the perforating guns can be removed
from the well. The plug is left behind and seals the casing of the
well at that location. Thus, a fracturing operation can now begin.
After the current stage is perforated with the guns and fractured,
the above noted operations are repeated to deploy a new plug, to
insulate a new stage, and to perforate and fracture the new stage
to further establish a fluid connection between the interior of the
casing and the formations.
[0006] An alternative mode of coupling the setting tool to the plug
is shown in FIG. 1B, where the setting kit 120 includes the
external sleeve 114 and a trapping mechanism 116, which is attached
to the internal sleeve 112, and the trapping mechanism 116 is
attached with screws 149, to a proximal end of the mandrel 132,
which means that the internal sleeve 112 does not extend all the
way through the bore 134 of the mandrel as in the case shown in
FIG. 1A. In this instance, the trapping mechanism 116 is attached
to the mandrel 132. The trapping mechanism 116 includes a wing 118
for trapping a ball that might be present inside the internal
sleeve. However, even for this case, screws 149 are used to connect
the mandrel to the trapping mechanism or to the internal sleeve.
The screws 149 are designed in both cases to break when a certain
force is applied, which is selected to be larger than the force
necessary to set the plug.
[0007] The operation of attaching the plug 130 to the setting tool
110 in the above cases may result in incorrectly attaching the plug
to the setting kit 120, or failing to fully attach the plug to the
setting kit as the holes that are made in the setting kit to
receive the screws 149 wear off in time and cannot be reused. Thus,
there is a need to have a novel way to connect a setting kit to a
plug so that there is only one way to connect these elements, and
also to avoid the presence of holes or screws for connecting these
parts to each other to extend their useful life.
SUMMARY
[0008] According to an embodiment, there is a quick connect device
for connecting a plug to a setting tool. The quick connect device
includes a collet having a body and plural fingers, a first end of
the collet is configured to be attached to a trapping mechanism
associated with the setting tool, and a second end of the collet
has the plural fingers, which are configured to be attached to the
plug. The second end automatically connects to the plug by only
pushing the second end onto the plug.
[0009] According to another embodiment, there is a system for
connecting a plug to a setting tool with a quick connect device.
The system includes the plug, which is configured to seal a bore of
a casing in a well, and the quick connect device. The quick connect
device has a collet that automatically engages and locks onto the
plug by only pushing the collet onto the plug.
[0010] According to still another embodiment, there is a method for
connecting a plug to a setting tool before being deployed in a
well. The method includes providing a plug having a mandrel, the
mandrel having a ring that extends around and away from the
mandrel; attaching a trapping mechanism to a collet; attaching the
collet to the ring of the plug by only pushing the collet onto the
plug; sliding the trapping mechanism, while connected to the collet
and the plug, inside an external sleeve of a setting kit; and
rotating the plug to attach threads of the trapping mechanism to an
internal sleeve of the setting tool.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate one or more
embodiments and, together with the description, explain these
embodiments. In the drawings:
[0012] FIG. 1A illustrates a traditional setting kit that is
connected to a bottom of a plug with plural screws;
[0013] FIG. 1B illustrates a setting kit having a trapping
mechanism that is connected to a top of a plug with plural
screws;
[0014] FIG. 2 illustrates a system that uses a quick connect device
to connect the setting tool to a plug with no screws;
[0015] FIG. 3 illustrates the quick connect device having a sloped
body that automatically connects to a ring of the plug by only
pushing the quick connect device onto the plug;
[0016] FIG. 4A illustrates a plug that has a groove in which the
ring is placed for being connected to the quick connect device;
[0017] FIG. 4B illustrates the ring being made of two parts that
connect to each other with male/female features;
[0018] FIG. 5 illustrates a plug that has the ring formed
integrally with a mandrel of the plug for being connected to the
quick connect device;
[0019] FIG. 6 illustrates the quick connect device having a
cylindrical body that automatically connects to a ring of the plug
by only pushing the quick connect device onto the plug;
[0020] FIG. 7 illustrates a plug that has a groove in which the
ring is placed for being connected to the quick connect device;
[0021] FIG. 8 illustrates the quick connect device having a collet
with plural fingers, and one finger is longer that the others for
engaging a dedicated slot into the plug; and
[0022] FIG. 9 is a flow chart of a method for attaching the setting
tool to the plug with the quick connect device.
DETAILED DESCRIPTION
[0023] The following description of the embodiments refers to the
accompanying drawings. The same reference numbers in different
drawings identify the same or similar elements. The following
detailed description does not limit the invention. Instead, the
scope of the invention is defined by the appended claims. The
following embodiments are discussed, for simplicity, with regard to
a quick connect device that attaches a setting tool having a
trapping mechanism to a plug. However, the embodiments discussed
herein are applicable to any tool that needs to be attached to
another tool, in a well, with no screws.
[0024] Reference throughout the specification to "one embodiment"
or "an embodiment" means that a particular feature, structure or
characteristic described in connection with an embodiment is
included in at least one embodiment of the subject matter
disclosed. Thus, the appearance of the phrases "in one embodiment"
or "in an embodiment" in various places throughout the
specification is not necessarily referring to the same embodiment.
Further, the particular features, structures or characteristics may
be combined in any suitable manner in one or more embodiments.
[0025] According to an embodiment, a quick connect device for
attaching a plug to a trapping mechanism of a setting tool includes
a collet having a thread at one end and plural fingers at an
opposite end. The threaded end connects to the setting tool or to
the trapping mechanism of the setting tool while the plural fingers
connect to the plug. No screws are used for these connections and
thus, no holes need to be made either in the plug or in the
trapping mechanism for this purpose. The collet automatically
connects to the plug by pushing the collet onto the plug. The quick
connect device and the trapping mechanism may be used with any
existing setting tool. In one embodiment, which is discussed next,
a so called FracTrap trapping mechanism (see, for example, U.S.
Pat. Nos. 9,617,816, 9,464,499, 9,765,590) is taken as an example
of a setting kit that is attached to the setting tool. A FracTrap
trapping mechanism is different from a traditional setting kit in
the sense that the trapping mechanism 116 (see FIG. 1B) is provided
inside an external sleeve, to trap the ball that seals the mandrel
of the plug. The plug used in this embodiment is a fracturing plug,
also called a frac plug. However, other plugs may also be used with
the discussed quick connect device.
[0026] According to the embodiment shown in FIG. 2, a quick connect
device 210 is provided between a trapping mechanism 116 associated
with a setting tool 220, and a plug 230 for achieving a mechanical
connection between these elements. FIG. 2 shows such a system 200
in which the quick connect device 210 has the trapping mechanism
116 and the quick connect device 210 fully located inside the
external sleeve 314, which is attached to the setting tool 220, and
for this reason the trapping mechanism 116 and the quick connect
device 210 are shown with a dash line. In one embodiment, the
external sleeve 314 and the trapping mechanism 116 form a setting
kit. As noted above, the setting tool 220 may be any known setting
tool. For simplicity of explanation, the setting tool 220 in this
embodiment is considered to have the internal and external sleeves
shown in FIGS. 1A and 1B. However, the plug 230 is modified to be
different from the plug 130 previously shown, as discussed
later.
[0027] FIG. 3 shows in more detail one possible implementation of
the quick connect device 210 and its functional relationships to
the setting tool 220 (more precisely, to the internal sleeve 222
and the external sleeve 224 of the setting tool), the trapping
mechanism 116, the external sleeve 314, and the plug 230. While the
external elements of the plug 230 may be similar to those of the
plug shown in FIGS. 1A and 1B, its internal mandrel 232 is
configured to have a head portion 232A, which is proximal to the
quick connect device 210, and is differently configurated form the
head of the mandrel 132. More specifically, as shown in FIGS. 3 and
4A, the head 232A of the mandrel 232 has, in one application, a
ring 234 formed around an entirety of the head. The ring 234 may be
formed of various materials, e.g., metal, plastic, elastomer, etc.
In one application, as shown in FIG. 4A, the ring 234 is
manufactured separately from the plug 230. A corresponding trench
236 (see FIG. 4A) is formed in the head 232A of the mandrel 232 and
the ring 234 is placed, partially, as shown in the figure, inside
the trench 236. In one application, the ring 234 may be made from
two or more parts 234A and 234B, as shown in FIG. 4B. The two parts
may be formed to have male 410 and female 412 features that fit
into each other so that the two halves 234A and 234B shows in the
figure can lock together. More than two parts may be used to form
the ring 234. The ring may be formed of the same material as the
mandrel 232 or a different material.
[0028] Alternatively, as shown in FIG. 5, the ring 234 may be made
integrally with the head 232A of the mandrel 232, i.e., to have a
monolithic structure. This means that both the mandrel 232 and the
ring 234 are made of the same material, for example, during the
same manufacturing process, and there is no trench or groove 236.
If the mandrel 232 is made of a composite material, the ring 234
may be made by over-molding during the manufacturing of the
mandrel. Any other process may be used for forming the ring 234 on
the mandrel 232. It is noted that irrespective of the
implementation of the ring 234 on the mandrel 232, the ring 234 is
designed to not slide relative to the mandrel 232. However, the
ring 234 is designed to break at a certain force, for example,
10,000 psi, to release the quick connect device 230, as discussed
later.
[0029] The connection between the quick connect device 210 and the
plug 230 is now discussed with regard to FIGS. 3 to 5. These
figures show the quick connect device 210 including a collet 214.
The collet 214, as shown in FIG. 3, is configured to have threads
213 at a first end 214A, that are configured to fit corresponding
threads of the trapping mechanism 116 of the setting tool 220.
Thus, the collet 214 is attached to the trapping mechanism 116 of
the setting tool 220. The collet 214 may have an internal bore 216
that allows a ball 310 to pass through. The ball 310 is hold in
place in an internal chamber 119 inside the trapping mechanism 116.
The ball 310 is sized to fit and close the bore 238 of the mandrel
232, after passing through the bore 216 of the collet 214. In other
words, as shown in FIG. 3, an interior shoulder 240 of the mandrel
232 is sized to receive the ball 310, and to form a seat that
together with the ball 310 seals the bore 238. However, the
seat/shoulder 240 is sized to not let the ball 310 pass through the
mandrel 232. Returning to the internal chamber 119, it has one or
more openings 218 for allowing a fluid to enter into or to exit
freely from the chamber.
[0030] The collet 214 is illustrated in more detail in FIGS. 4A and
5 and has a body 400 that includes threads 402 at a first end 214A,
to connect to the threads 213 of the trapping mechanism 116 of the
setting tool 220. The body 400 is shaped to increase in diameter
from the first end 214A towards a second end 214B, i.e., to have a
sloped side 420. The other end 214B of the collet 214 is shaped to
have plural fingers 402-I, which are separated by each other by a
corresponding gap G. Each finger 402-1 may have a corresponding tab
404-1, as shown in FIGS. 4A and 5, and the tab is configured to
engage the ring 234 so that the collet 214 is fixedly and securely
attached to the mandrel 232 of the plug 230 by simply pushing the
collet onto the plug, over the ring 234. Because the body of the
collet is made with a slope 420, the fingers 402-I may inherit the
same slope. The collet may be made of any material. In one
application, the collet is made of such a material that the fingers
are flexible, i.e., when the tabs of the fingers engage the ring,
the fingers bent upwards to embrace the ring of the mandrel. Note
that FIGS. 4A and 5 show only two fingers 402-1 and 402-2 with
their corresponding tabs 404-1 and 404-2 being engaged to the ring
234. However, in one application, all the fingers have
corresponding tabs and each tab engages the ring 234.
[0031] The tabs and/or the ring are shaped and their material is
selected in such a way so that a desired maximum force can be
applied by the collet on the mandrel. If the force applied by the
setting tool to the mandrel through the collet becomes larger than
the desired maximum force, the ring 234 is designed to break and to
release the tabs 404, so that the collet 214 can separate from the
plug 230, the plug 230 remains set in place, and the setting tool
220 with the trapping mechanism 116 and the collet 214 can be
retrieved from the well. In one application, the ring is
exclusively part of the plug and the collet does not even directly
contact or touch the plug, only the ring. FIGS. 6 and 7 show
another implementation of the quick connect device 210, in which
the collet 214 has no sloped sides, i.e., its body is cylindrical.
All the other elements of this implementation are similar to those
shown in FIGS. 3 to 5 and thus, their description is omitted
herein.
[0032] Due to the fingers 402-I having the tabs 404-I on the quick
connect device 210, and the ring 234 on the plug 230, there are no
holes made either in the mandrel of the plug or in the internal
sleeve or the trapping mechanism of the setting kit for attaching
these elements to each other. After the setting tool 220 sets the
plug 230, just the ring 234 of the plug 230 is broken, no other
component. This means that as soon as the setting tool 220, the
trapping mechanism 116, the external sleeve 314, and the quick
connect device 210 are brought to the surface, there is no need to
remove any screw, but simply a new plug 230 is attached to the
collet 214 so that the tabs 404-I of the collet engage the ring 234
of the new plug and the connection between the plug and the setting
tool is established. Because of this simplified connection process,
the operator of the setting tool and plug cannot misconnect these
elements with the trapping mechanism as they cannot be connected in
any other way. Also, the multiple use of the setting tool, the
trapping mechanism, the external sleeve, and the quick connect
device do not damage any of their components, as only the ring of
the plug 230 is damaged in the process. Therefore, as long as a new
plug 230 is provided, the system 200 can be used multiple times
with the same setting tool and quick connect device.
[0033] In one embodiment, which is illustrated in FIG. 8, one
finger 402-3 has in addition to the corresponding tab 404-3, an
extension 406-3, which is monolithically formed with the finger
402-3. The extension 406-3 makes the finger 402-3 to be longer than
all other fingers 402-I. A corresponding longer slot 233 is formed
in the head 232A of the mandrel 232, to accommodate this extension.
This means that when the operator of the setting tool connects the
plug 230 to the collet 214, the plug needs to be rotated so that
the longer slot 233 matches and receives the extension 406-3 of the
finger 402-3. Therefore, the plug can be added to the collet only
if their angular orientations are aligned, i.e., the longer slot
233 acts as a key. In this way, after the collet is mechanically
connected to the plug, the plug and the collet rotate as a single
element, i.e., the plug cannot rotate relative to the collet. This
feature ensures that the collet 214 also rotates with the plug, and
thus, when the collet 214 is attached to the trapping mechanism 116
of the setting tool 220, these elements rotate in unison. In this
respect, note that the collet 214 is fully disposed inside the
external sleeve 314 and thus, it cannot be directly attached to the
internal sleeve 112 unless it is connected to the plug 230. In
other words, it is much easier to attach the collet to the plug and
then the connected elements are passed through the external sleeve
314 of the setting kit, which is already attached to the setting
tool, to connect the collar to the trapping mechanism. In one
application, it is possible to connect the collar to the plug and
to the trapping mechanism and then to slide these connected
elements to the internal sleeve of the setting tool. While FIG. 8
shows the sloped collet 214, the same configuration can be
implemented for the non-slopped collet.
[0034] In another embodiment, the quick connect device may use a
reversed tabbed collet where the tabs stick outward rather than
inward and thus the collet bends in instead of out, i.e., the tabs
and the fingers enter inside the mandrel to engage the ring or a
corresponding structure, for example, a trench. Also, a spring and
ball bearing connection can be used in one application to connect
the collet to the plug. A connection via a J-lock could also work
to hook up a setting adapter to a frac plug to be set in the
well.
[0035] The above discussed systems prevent any deviation from a
standard procedure of assembly of the setting tool to a plug, at
the well site. This approach reduces misruns due to the assembly at
the well site where screws can be left out of the plug, thus
causing a low set force and improper seal between the plug and the
casing of the well. In one application, the system 200 is faster
and easier to assemble, leaves less hard metal in the well, as all
that is left behind is a thin soft metal ring. In yet another
application, the system 200 improves the tool life and longevity of
the tool with replaceable collet. The two piece shear ring shown in
FIG. 4B overcomes the challenge of having a single shear ring over
molded in a large horizontal mold.
[0036] A method for attaching the plug to a setting tool is now
discussed with regard to FIG. 9. The method includes a step 900 of
providing a plug 230 having a mandrel 232, the mandrel 232 having a
ring 234 that extends around and away from the mandrel 232, a step
902 of attaching a trapping mechanism 116 to a collet 214, a step
904 of attaching the collet 214 to the ring 234 of the plug 230 by
only pushing the collet 214 onto the plug 230, a step 906 of
sliding the connected collet 214 and the plug 230, inside an
external sleeve 314 of a setting kit, to contact an internal sleeve
222 of the setting tool 220, and a step 908 of rotating the plug
230 to attach threads of the trapping mechanism 116 to the internal
sleeve 222 of the setting tool 220.
[0037] The disclosed embodiments provide methods and systems for
connecting a plug to a setting tool having a trapping mechanism,
without the use of screws. It should be understood that this
description is not intended to limit the invention. On the
contrary, the exemplary embodiments are intended to cover
alternatives, modifications and equivalents, which are included in
the spirit and scope of the invention as defined by the appended
claims. Further, in the detailed description of the exemplary
embodiments, numerous specific details are set forth in order to
provide a comprehensive understanding of the claimed invention.
However, one skilled in the art would understand that various
embodiments may be practiced without such specific details.
[0038] Although the features and elements of the present exemplary
embodiments are described in the embodiments in particular
combinations, each feature or element can be used alone without the
other features and elements of the embodiments or in various
combinations with or without other features and elements disclosed
herein.
[0039] This written description uses examples of the subject matter
disclosed to enable any person skilled in the art to practice the
same, including making and using any devices or systems and
performing any incorporated methods. The patentable scope of the
subject matter is defined by the claims, and may include other
examples that occur to those skilled in the art. Such other
examples are intended to be within the scope of the claims.
* * * * *