U.S. patent application number 14/237416 was filed with the patent office on 2014-11-27 for support bracket for selective fire switches.
This patent application is currently assigned to Halliburton Energy Services, Inc.. The applicant listed for this patent is Halliburton Energy Services, Inc.. Invention is credited to Maquelle Lee Bienvenu, Donald Crawford, Paul Anthony Molina, Tony Tran.
Application Number | 20140345485 14/237416 |
Document ID | / |
Family ID | 51689884 |
Filed Date | 2014-11-27 |
United States Patent
Application |
20140345485 |
Kind Code |
A1 |
Molina; Paul Anthony ; et
al. |
November 27, 2014 |
Support Bracket for Selective Fire Switches
Abstract
Disclosed is a robust selective fire switch. One exemplary
selective fire switch includes a switch housing, a plunger having a
head and a body extending longitudinally from the head, the head
extending at least partially into an opening defined in the switch
housing, a first post and a second post arranged on opposing sides
of the switch housing, and a filament wire coupled to and extending
between both the first and second posts, the filament wire being in
contact with the plunger and thereby securing the plunger in a
seated configuration within the switch housing.
Inventors: |
Molina; Paul Anthony;
(Houston, TX) ; Bienvenu; Maquelle Lee; (Cypress,
TX) ; Tran; Tony; (Houston, TX) ; Crawford;
Donald; (Spring, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Halliburton Energy Services, Inc. |
Houston |
TX |
US |
|
|
Assignee: |
Halliburton Energy Services,
Inc.
Houston
TX
|
Family ID: |
51689884 |
Appl. No.: |
14/237416 |
Filed: |
April 11, 2013 |
PCT Filed: |
April 11, 2013 |
PCT NO: |
PCT/US2013/036204 |
371 Date: |
February 6, 2014 |
Current U.S.
Class: |
102/202.14 |
Current CPC
Class: |
E21B 43/1185 20130101;
H01H 3/16 20130101 |
Class at
Publication: |
102/202.14 |
International
Class: |
E21B 43/1185 20060101
E21B043/1185 |
Claims
1. A selective fire switch, comprising: a switch housing; a plunger
having a head and a body, the body extending longitudinally from
the head and at least partially into an opening defined in the
switch housing; a first post and a second post arranged on opposing
sides of the switch housing; and a filament wire coupled to and
extending between both the first and second posts across the switch
housing, the filament wire being in contact with the plunger and
thereby securing the plunger in a seated configuration within the
switch housing.
2. The selective fire switch of claim 1, wherein the filament wire
extends from the first post to the second post and back to first
post from the second post.
3. The selective fire switch of claim 1, wherein the first and
second posts support the filament wire across the switch housing in
a substantially tangential relationship with respect to the head of
the plunger.
4. The selective fire switch of claim 1, wherein at least one of
the first and second posts define a lateral extension that extends
a short distance over the switch housing.
5. The selective fire switch of claim 1, wherein the filament wire
is coupled to one or both of the first and second posts by at least
one of soldering, welding, brazing, or mechanical fasteners.
6. The selective fire switch of claim 1, wherein at least one of
the first and second posts is electrically conductive and
configured to apply a voltage across the filament wire.
7. The selective fire switch of claim 1 or 6, wherein the filament
wire is configured to fail upon being subjected to the voltage, and
wherein, when the filament wire fails, the plunger is able to move
from the seated configuration to an extended configuration.
8. The selective fire switch of claim 1, wherein the first post
comprises an input stanchion and an output stanchion, the input and
output stanchions being electrically conductive and structurally
offset from each other on a first side of the switch housing.
9. The selective fire switch of claim 1 or 8, wherein the filament
wire comprises a first portion coupled to the input stanchion and
extending to the second post arranged on a second side of the
switch housing, and a second portion extending from the second post
and coupled to the output stanchion.
10. The selective fire switch of claim 1, further comprising at
least one groove defined in the head of the plunger and being
configured to receive or engage the filament wire as it extends
across the switch housing.
11. The selective fire switch of claim 1 or 10, wherein the
filament wire comprises a first portion and a second portion and
the at least one groove comprises a first groove and a second
groove defined on opposing sides of the head, the first groove
being configured to engage the first portion and the second groove
being configured to engage the second portion.
12. The selective fire switch of claim 1 or 10, wherein the at
least one groove is centrally defined on the head and the filament
wire rests within the at least one groove.
13. The selective fire switch of claim 1 or 10, wherein the at
least one groove comprises one or more conduits defined through the
head and configured to receive the filament wire therethrough.
14. A method of operating a selective fire switch, comprising:
securing a plunger in a seated configuration within a switch
housing with a filament wire that engages the plunger, the filament
wire being coupled to and extending between a first post and a
second post arranged on opposing sides of the switch housing and
extending across the switch housing; applying a voltage across the
filament wire; burning the filament wire with the voltage; and
moving the plunger from the seated configuration to an extended
configuration with respect to the switch housing.
15. The method of claim 14, wherein the plunger has a head and a
body extending longitudinally from the head and at least partially
into an opening defined in the switch housing, and wherein securing
the plunger in the seated configuration further comprises
supporting the filament wire with the first and second posts in a
substantially tangential relationship with respect to the head.
16. The method of claim 14 or 15, wherein supporting the filament
wire with the first and second posts further comprises supporting
the filament wire with a lateral extension defined on at least one
of the first and second posts, the lateral extension extending a
short distance over the switch housing.
17. The method of claim 14 or 15, further comprising engaging the
filament wire in or on at least one groove defined in the head of
the plunger.
18. The method of claim 14 or 15, wherein moving the plunger from
the seated configuration to the extended configuration further
comprises: engaging the body of the plunger on a toggle mechanism
arranged within the switch housing, the toggle mechanism being
spring loaded; and moving the plunger into the extended
configuration with the toggle mechanism once the filament wire is
burned.
19. The method of claim 14, wherein applying the voltage across the
filament wire comprises: supplying a current to the first post, the
first post being electrically conductive; and conducting the
current from the first post to the filament wire.
20. The method of claim 14, wherein the first post comprises an
input stanchion and an output stanchion, the input and output
stanchions being electrically conductive and structurally offset
from each other, and wherein apply the voltage across the filament
wire comprises: supplying a current to the input stanchion;
conducting the current from the input stanchion to a first portion
of the filament wire which extends to the second post; and
conducting the current to the output stanchion via a second portion
of the filament wire that extends from the second post.
21. A selective fire switch, comprising: a switch housing; a
plunger extending at least partially into an opening defined in the
switch housing; an input stanchion and an output stanchion arranged
on a first side of the switch housing, the input and output
stanchions being electrically conductive and structurally offset
from each other; a post arranged on a second side of the switch
housing opposite the first side of the switch housing; and a
filament wire having a first portion coupled to the input stanchion
and extending to the post across the switch housing, and a second
portion extending from the post across the switch housing and to
the output stanchion, the filament wire being in contact with the
plunger and thereby maintaining the plunger in a seated
configuration within the switch housing.
22. The selective fire switch of claim 21, wherein the filament
wire is supported across the switch housing between the input and
output stanchions and the post in a substantially tangential
relationship with respect to the plunger.
23. The selective fire switch of claim 21, wherein at least one of
the input and output stanchions and the post defines a lateral
extension that extends a short distance over the switch
housing.
24. The selective fire switch of claim 21, wherein the filament
wire is coupled to at least one of the input and output stanchions
and the post by at least one of soldering, welding, brazing, or
mechanical fasteners.
25. The selective fire switch of claim 21, wherein the input and
output stanchions are electrically conductive and configured to
route a voltage through the filament wire and around the post.
26. The selective fire switch of claim 21 or 25, wherein the
filament wire is configured to fail upon being subjected to the
voltage, and wherein, when the filament wire fails, the plunger is
able to move from the seated configuration to an extended
configuration.
27. The selective fire switch of claim 21, wherein the plunger has
a head and at least one groove defined in the head, the at least
one groove being configured to receive or engage the filament wire
as it extends across the switch housing.
28. The selective fire switch of claim 21 or 27, wherein the at
least groove comprises a first groove and a second groove defined
on opposing sides of the head, the first groove being configured to
engage the first portion of the filament wire and the second groove
being configured to engage the second portion of the filament
wire.
29. The selective fire switch of claim 21 or 27, wherein the at
least one groove comprises first and second conduits defined
through the head and configured to receive the first and second
portions of the filament wire, respectively, therethrough.
Description
BACKGROUND
[0001] The present disclosure relates generally to wellbore casing
perforation operations and, more particularly, to a more robust
selective fire switch used in casing perforating guns.
[0002] After drilling the various sections of a subterranean
wellbore that traverses a hydrocarbon-bearing formation, individual
lengths of relatively large diameter metal tubulars are typically
secured together to form a casing string that is positioned within
the wellbore. This casing string increases the integrity of the
wellbore and provides a path for producing fluids extracted from
producing intervals in the formation to the surface.
Conventionally, the casing string is cemented within the wellbore.
To produce fluids into the casing string, hydraulic openings or
perforations must be made through the casing string and the cement,
and extend a short distance into the surrounding subterranean
formation.
[0003] Typically, these perforations are created by detonating a
series of shaped charges that are disposed within the casing string
and are positioned adjacent to the formation. Specifically, one or
more perforating guns are loaded with shaped charges that are
connected with a detonator via a detonating cord. The perforating
guns are then connected within a tool string that is lowered into
the cased wellbore at the end of a tubing string, wireline,
slickline, coiled tubing or other type of downhole conveyance. Once
the perforating guns are properly positioned in the wellbore such
that the shaped charges are adjacent the formation to be
perforated, the shaped charges are detonated, thereby creating the
desired hydraulic openings in to the casing string.
[0004] To detonate a particular shaped charge, a voltage is
commonly sent to a corresponding selective fire switch that
includes a filament wire configured to be burned or otherwise
disintegrate upon being subjected to a predetermined amount of
voltage. The filament wire also typically supports a plunger used
to switch the fire switch into detonation mode. Once the filament
wire is burned, the plunger is able to switch positions, thereby
placing the fire switch in detonation mode. In traditional
selective fire switches, the filament wire is usually supported
with a pliable terminal or turret and may be susceptible to tensile
stresses and environmental vibrations. Upon experiencing extreme
vibrations, for example, especially vibrations stemming from
adjacent detonations or explosions, the filament wire can fail or
may otherwise be rendered inoperable before its intended operation
can be carried out.
SUMMARY OF THE DISCLOSURE
[0005] The present disclosure relates generally to wellbore casing
perforation operations and, more particularly, to a more robust
selective fire switch used in casing perforating guns.
[0006] In some embodiments, a selective fire switch is disclosed
and may include a switch housing, a plunger having a head and a
body, the body extending longitudinally from the head and at least
partially into an opening defined in the switch housing, a first
post and a second post arranged on opposing sides of the switch
housing, and a filament wire coupled to and extending between both
the first and second posts across the switch housing, the filament
wire being in contact with the plunger and thereby securing the
plunger in a seated configuration within the switch housing.
[0007] In some embodiments, a method of operating a selective fire
switch is disclosed. The method may include securing a plunger in a
seated configuration within a switch housing with a filament wire
that engages the plunger, the filament wire being coupled to and
extending between a first post and a second post arranged on
opposing sides of the switch housing and extending across the
switch housing, applying a voltage across the filament wire,
burning the filament wire with the voltage, and moving the plunger
from the seated configuration to an extended configuration with
respect to the switch housing.
[0008] In some embodiments, another selective fire switch is
disclosed and may include a switch housing, a plunger extending at
least partially into an opening defined in the switch housing, an
input stanchion and an output stanchion arranged on a first side of
the switch housing, the input and output stanchions being
electrically conductive and structurally offset from each other, a
post arranged on a second side of the switch housing opposite the
first side of the switch housing, and a filament wire having a
first portion coupled to the input stanchion and extending to the
post across the switch housing, and a second portion extending from
the post across the switch housing and to the output stanchion, the
filament wire being in contact with the plunger and thereby
maintaining the plunger in a seated configuration within the switch
housing.
[0009] The features of the present disclosure will be readily
apparent to those skilled in the art upon a reading of the
description of the embodiments that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The following figures are included to illustrate certain
aspects of the present disclosure, and should not be viewed as
exclusive embodiments. The subject matter disclosed is capable of
considerable modifications, alterations, combinations, and
equivalents in form and function, as will occur to those skilled in
the art and having the benefit of this disclosure.
[0011] FIG. 1 is a well system that may embody or otherwise employ
one or more principles of the present disclosure, according to one
or more embodiments.
[0012] FIGS. 2A-2D are various views of an exemplary selective fire
switch, according to one or more embodiments.
[0013] FIGS. 3A and 3B are isometric views of another exemplary
selective fire switch, according to one or more embodiments.
[0014] FIGS. 4A-4D illustrate various exemplary embodiments of a
plunger that can be used with the selective fire switches of FIGS.
2A-2D or 3A-3B, according to one or more embodiments.
DETAILED DESCRIPTION
[0015] The present disclosure relates generally to wellbore casing
perforation operations and, more particularly, to a more robust
selective fire switch used in casing perforating guns.
[0016] The present disclosure describes a selective fire switch
that has structural stanchions or posts configured to reliably
support a filament wire that is to be burned or otherwise
disintegrated in the process of setting a detonator. The posts
provide additional structural strength to the switch and the
filament wire such that the filament wire is able to sustain heavy
shock loads and vibrations, such as vibrations that are sustained
through detonations of adjacent perforation charges. Moreover, the
posts may include lateral extensions that bend over or extend
across the switch a short distance in order to decrease the
deflection potential of the filament wire, thereby reducing the
potential for tensile fatigue in the filament wire before its
intended operation can be undertaken.
[0017] Referring to FIG. 1, illustrated is a well system 100 that
may embody or otherwise employ one or more principles of the
present disclosure. The well system 100 may include an offshore oil
and gas platform 102 centered over a submerged oil and gas
formation 104 located below a sea floor 106. Even though FIG. 1
depicts an offshore oil and gas platform 102, it will be
appreciated by those skilled in the art that the various
embodiments discussed herein are equally well suited for use in
conjunction with other types of oil and gas rigs, such as
land-based oil and gas rigs or rigs located at any other
geographical site. A subsea conduit 108 extends from a deck 110 of
the platform 102 to a wellhead installation 112 including one or
more subsea blow-out preventers 114. The platform 102 has a
hoisting apparatus 116 and a derrick 118 for raising and lowering
pipe strings, such as work string 120, within the subsea conduit
108.
[0018] As depicted, a wellbore 122 extends through the various
earth strata including a hydrocarbon-bearing formation 104. A
casing string 124 is cemented within the wellbore 122 using cement
126. The work string 120 includes various tools such as a plurality
of perforating gun assemblies 134 arranged at or near its distal
end. When it is desired to perforate the casing string 124 and
cement 126 in order to provide fluid communication to the formation
104, the work string 120 is lowered through the casing string 124
until the perforating guns 134 are properly positioned relative to
the formation 104. Thereafter, one or more shaped charges within
the string of perforating guns are sequentially fired, either in an
uphole to downhole or a downhole to uphole direction. Upon
detonation, the liners of the shaped charges form jets that create
a spaced series of perforations extending outwardly through the
casing string 124, the cement 126, and into surrounding portions of
the formation 104, thereby allowing fluid communication between the
formation 104 and the wellbore 122.
[0019] In the illustrated embodiment, the wellbore 122 has an
initial, generally vertical portion 128 and a lower, generally
deviated or horizontal portion 130. The work string 120 may include
a retrievable packer 132 which may be sealingly engaged with the
casing string 124 in the vertical portion 128 of the wellbore 122.
The perforating guns 134 may have a ported nipple 136 arranged at
their upper or proximal end, below which is a time domain firer
138. The time domain firer 138 may be arranged at the upper end of
a tandem gun set 140 including first and second guns 142 and 144.
In the illustrated embodiment, a plurality of such gun sets 140 are
utilized, each including a first gun 142 and a second gun 144.
[0020] Positioned between each gun set 140 may be a blank pipe
section 146 used to control and optimize the pressure conditions in
the wellbore 122 immediately after detonation of the shaped
charges. In other embodiments, the blank pipe sections 146 may
serve as secondary pressure generators. It should be understood by
those skilled in the art that any arrangement of perforating guns
may be utilized in conjunction with the present disclosure,
including both more and less sections of blank pipe 146 as well as
no sections of blank pipe 146, without departing from the scope of
the disclosure. It will also be appreciated by those skilled in the
art that even though FIG. 1 depicts the perforating guns 134 and
its associated components as being arranged to perforate a
horizontal section of the wellbore 122, the embodiments described
herein are equally applicable for use in portions of the wellbore
122 that are vertical, deviated, slanted or otherwise.
[0021] Referring now to FIGS. 2A-2D, illustrated are various views
of an exemplary selective fire switch 200 (hereinafter "switch")
that may be used in conjunction with one or more of the perforating
guns 134 of FIG. 1, according to one or more embodiments. In
particular, FIGS. 2A and 2B illustrate isometric and end views of
the switch 200, respectively, in a secured configuration (i.e., a
position opposing a load), and FIGS. 2C and 2D illustrate isometric
and end views of the switch 200, respectively, in an actuated
configuration (i.e., a position after functioning). Those skilled
in the art, will readily recognize that the embodiments disclosed
herein may equally be applied to other technology fields besides
the oil and gas industry. Indeed, the various embodiments of
selective fire switches disclosed herein may be used in any field
where it may prove advantageous to have a robust and reliable
firing switch. For example, the exemplary selective fire switches
may be used in any device requiring a mechanism capable of
enabling/disabling or engaging/releasing something.
[0022] The switch 200 depicted in FIGS. 2A-2D may include a switch
housing 202 coupled to or otherwise supported by a circuit board
204, such as a printed circuit board or the like. The switch
housing 202 may be made of one or more non-conductive or insulative
materials such as, but not limited to, plastics, polymers,
ceramics, glasses, composites, combinations thereof, and the like.
The switch 200 may include a plunger 206 at least partially
arranged within the housing 202 and movable between a seated
configuration, as depicted in FIGS. 2A and 2B, and an extended
configuration, as depicted in FIGS. 2C and 2D. The plunger 206 may
also be made of one or more non-conductive or insulative materials
such as, but not limited to, plastics, polymers, ceramics, glasses,
composites, nylon, combinations thereof, and the like.
[0023] The plunger 206 may have a head 208 and a body 210 (FIG. 2B)
that extends longitudinally from the head 208. As depicted in FIG.
2B, the body 210 may be configured to extend within an opening 212
defined or otherwise formed within the housing 202. The head 208
may exhibit a diameter that is greater than the diameter of the
opening 212 such that the head 208 is prevented from extending into
the opening 212 and otherwise generally rests on the exterior of
the housing 202 when the plunger 206 is in its seated
configuration.
[0024] The switch 200 may further include a filament wire 214 that
may extend across at least a portion of the housing 202 and may be
supported across the housing 202 by at least a first post 216a and
a second post 216b. The filament wire 214, also known as a fuse
wire or heater wire, may also be configured to at least partially
maintain or otherwise secure the plunger 206 in its seated
configuration within the housing 202. In some embodiments, for
example, the plunger 206 may define or otherwise include at least
one groove 218 configured to receive or engage the filament wire
214. In the embodiment of FIGS. 2A-2D, for instance, the at least
one groove 218 may include a first groove 218a and a second groove
218b defined on opposing sides of the head 208 and portions of the
filament wire 214 may rest on or otherwise be received in each of
the first and second grooves 218a,b.
[0025] The filament wire 214 is shown in FIGS. 2A-2D as extending
from the first post 216a to the second post 216b, extending around
the second post 216a and returning to the first post 216a. Those
skilled in the art will readily appreciate, however, that the
filament wire 214 may extend between the first and second posts
216a,b in various other configurations, without departing from the
scope of the disclosure. In some embodiments, for example, the
filament wire 214 may include only a single wire strand extension
that extends between or otherwise connects the first post 216a to
the second post 216. As a result, and as will be described in
greater detail below, the at least one groove 218 may take on
several different configurations to accommodate the differing
configurations of the filament wire 214, without departing from the
scope of the disclosure.
[0026] In its seated configuration, as shown in FIG. 2B, the distal
end of the body 210 of the plunger 206 may engage or otherwise bias
a toggle mechanism 220. In some embodiments, the toggle mechanism
220 may be a single-throw, single-pole switch, as generally known
by those skilled in the art. In other embodiments, the toggle
mechanism 220 may encompass any other type of toggling or switching
device capable of generally performing the actions of the toggle
mechanism 220 described herein, such as relays, contactors,
actuators, spring devices, valves, inflatable or expandable
apparatus (whether inflating speed control or not), and the like.
In at least one embodiment, the toggle mechanism 220 may be similar
to or otherwise related to the switches described in co-owned U.S.
patent application Ser. No. 13/494,075, filed on Jun. 12, 2012, the
contents of which are hereby incorporated by reference in their
entirety. Accordingly, the toggle mechanism 220 depicted in FIGS.
2B and 2D is shown and described merely for illustrative purposes
and should not be considered limiting to the scope of the
disclosure.
[0027] As illustrated, the exemplary toggle mechanism 220 may
include a wiper 222 that may be movable between a first position,
as shown in FIG. 2B, where the wiper 222 makes contact with a first
contact 224a, and a second position, as shown in FIG. 2D, where the
wiper 222 makes contact with a second contact 224b. The wiper 222
may be spring biased or otherwise naturally tending towards contact
with the second contact 224b. The wiper 222 may be made of an
electrically conductive material, such as copper or bronze. In at
least one embodiment, the wiper 222 may be a wire or the like.
[0028] In order to maintain the wiper 222 in the first position or
otherwise in contact with the first contact 224a, the body 210 of
the plunger 206 may be extended through the opening 212 such that
it engages the wiper 222 and overcomes its spring force until the
wiper 222 makes contact with the first contact 224a. In such a
configuration, the plunger 206 is in its seated configuration and
may be maintained therein with the filament wire 214 biasing
against a portion of the head 208, such as the at least one groove
218. In the event the filament wire 214 is severed or otherwise
fails, such as is depicted in FIGS. 2C-2D, the plunger 206 may be
moved or otherwise forced in the upward direction as the wiper 222
moves to its second position and makes contact with the second
contact 224b.
[0029] The filament wire 214 may be coupled to or otherwise
attached to the first and second posts 216a,b which generally serve
as stanchions that support the filament wire 214 across the housing
202 and hold the filament wire 214 in a substantially tangential
relationship with the head 208 of the plunger 206. As illustrated,
the first and second posts 216a,b may be arranged on opposing sides
of the housing 202 such that the filament wire 214 generally
extends across the top of the housing 202. In some embodiments, the
filament wire 214 may be soldered, welded, or brazed to one or both
of the first and second posts 216a,b, or otherwise attached thereto
using a glue or any chemical adhesive known to those skilled in the
art. In other embodiments, the filament wire 214 may be fastened to
one or both of the first and second posts 216a,b using one or more
mechanical fasteners such as, but not limited to, screws, clamps,
wedges, rivets, clips, heat shrink tubing, combinations thereof,
and the like. In yet other embodiments, the filament wire 214 may
form an integral part of one or both of the first and second posts
216a,b, without departing from the scope of the disclosure.
[0030] At their respective bases, the first and second posts 216a,b
may be soldered to, mechanically fastened to, or otherwise form an
integral part of the circuit board 204. In some embodiments, both
the first and second posts 216a,b may be electrically conductive or
otherwise made of a material that is able to conduct an electrical
current therethrough. In other embodiments, however, one of the
first or second posts 216a,b may be non-conductive or otherwise
made of an insulative material, without departing from the scope of
the disclosure. In the illustrated embodiment, both the first and
second posts 216a,b are electrically conductive, as will be
described below.
[0031] In one or more embodiments, at least one of the first and
second posts 216a,b may include or otherwise define a lateral
extension that extends or otherwise reaches a short distance across
or over the housing 202. In FIGS. 2A-2D, each of the first and
second posts 216a,b are depicted as having a lateral extension,
labeled as a first lateral extension 226a and a second lateral
extension 226b. The first and second lateral extensions 226a,b may
prove advantageous in providing additional support to the filament
wire 214 such that the filament wire 214 may be less susceptible to
wire fatigue or mechanical vibrations. The distance that each
lateral extension 226a,b extends across or over the housing 202 may
vary, depending on the application. In at least one embodiment, for
example, one or both of the lateral extensions 226a,b may extend to
but not obstruct movement of the plunger 206 such that the plunger
206 is nonetheless able to move to its extended configuration.
[0032] According to one or more embodiments of the disclosure, the
switch 200 may be used to set or otherwise arm an igniter or
detonator (not shown) used to detonate a corresponding perforating
charge (not shown), such as is used in casing perforating
operations briefly described above. With the switch 200 and the
plunger 206 in their secured and seated configurations,
respectively, as depicted in FIGS. 2A and 2B, exemplary operation
of the switch 200 is now provided.
[0033] A first voltage 227 may be sent to the toggle mechanism 220
via a power line 228. The power line 228 may be communicably or
otherwise electrically coupled to a power source (not shown) either
arranged adjacent the switch 200 (e.g., downhole) or at a remote
location (e.g., via wireline, slickline, e-line, etc.), such as the
platform 102 of FIG. 1. The first voltage 227 may be a positive or
a negative voltage, depending on the perforating application and
how many switches 200 are to be activated. Those skilled in the art
will readily appreciate that the power line 228 may receive the
first voltage 227 via several different methods or devices, without
departing from the scope of the disclosure.
[0034] With the plunger 206 in its seated configuration, the wiper
222 is held in its first position and therefore in contact with the
first contact 224a. Accordingly, the first voltage 227 is conveyed
to the first contact 224a which may be configured to convey the
first voltage 227 to a first conductor line 230a. In some
embodiments, the first conductor line 230a may be communicably or
otherwise electrically coupled to the first post 216a, such that
the first voltage 227 is conveyed to the first post 216a via the
first conductor line 230a. As shown in FIG. 2A, the first conductor
line 230a is shown as extending to the first post 216a as part of
the design of the circuit board 204. At least one diode 232 (FIG.
2A) may be arranged in the first conductor line 230a and otherwise
configured to determine the polarity of the first voltage 227 such
that the correct voltage polarity is provided to the first post
216a for proper operation.
[0035] With continued reference to FIG. 2A, in some embodiments the
first voltage 227 may be applied across the first post 216a and to
the filament wire 214 which conveys the first voltage 227 to the
second post 216b. In some embodiments, the filament wire 214 may
extend at least partially down the first post 216 toward the
circuit board 204. The second post 216b may then convey the first
voltage 227 downstream to ground, for example. The filament wire
214 may be manufactured or otherwise configured to exhibit a
predetermined resistance per unit length. The first voltage 227 may
be a predetermined voltage used to overcome the predetermined
resistance of the filament wire 214 such that as the first voltage
227 is applied across the filament wire 214, the filament wire 214
may be configured to burn, disintegrate, or otherwise fail.
[0036] Those skilled in the art will readily recognize the several
advantages of the first and second posts 216a,b. For example, the
first and second posts 216a,b may reliably secure the filament wire
214 across the top of the housing 202 while holding the plunger 206
in its seated configuration. Moreover, the first and second posts
216a,b provide additional structural strength to the switch 200 and
the filament wire 214 such that the filament wire 214 may be able
to sustain heavy shock loads and vibrations. The lateral extensions
226a,b of each post 216a,b, respectively, may serve to decrease the
length and deflection of the filament wire 214, thereby reducing
the potential for tensile fatigue, commonly referred to as "support
post fatigue." As a result, the switch 200 provides a more robust
and reliable means of setting a detonator.
[0037] Referring to FIGS. 2C-2D, the filament wire 214 is depicted
as burned or otherwise disintegrated after having been subjected to
the first voltage 227. Without the filament wire 214 securing or
maintaining the plunger 206 in its seated configuration, the spring
force of the wiper 222 may overcome the weight of the plunger 206,
thereby moving the plunger 206 to its extended configuration as the
wiper 222 moves to its second position. With the wiper 222 in its
second position, contact is made between the wiper 222 and the
second contact 224b and the power source (not shown) is thereby
placed in electrical communication with the igniter or detonator
(not shown). Specifically, the power line 228 may be electrically
coupled through the wiper 222 and the second contact 224b to a
second conductor line 230b which may be coupled to the
detonator.
[0038] To activate the detonator, and thereby detonate a
corresponding perforating charge, a second voltage 234 may be
applied across the power line 228 and conveyed through the wiper
222, the second contact 224b, and the second conductor line 230b
which applies the second voltage 234 to the detonator. Similar to
the first voltage 227, the second voltage 234 may be a positive or
a negative voltage, depending on the perforating application and
how many switches 200 are to be activated.
[0039] Referring now to FIGS. 3A and 3B, illustrated are isometric
views of another exemplary selective fire switch 300 (hereinafter
"switch"), according to one or more embodiments. The switch 300 may
be similar in some respects to the switch 200 of FIGS. 2A-2D and
therefore may be best understood with reference thereto, where like
numerals indicate like elements that will not be described again in
detail. Similar to the switch 200 of FIGS. 2A-2D, the switch 300
includes the switch housing 202 coupled to or otherwise supported
by the circuit board 204. The switch 300 may also include the
plunger 206 at least partially arranged within the housing 202 and
movable between seated and extended configurations, as depicted in
FIG. 3A and FIG. 3B, respectively.
[0040] Unlike the switch 200 of FIGS. 2A-2D, however, the first
post 216a of the switch 300 may include or otherwise encompass an
input stanchion 302a and an output stanchion 302b. As illustrated,
the input stanchion 302a may be communicably or otherwise
electrically coupled to the first conductor line 230a. The output
stanchion 302b may be structurally offset from the input stanchion
302a and otherwise insulated from contact with the input stanchion
302a except for through the filament wire 214, as will be described
below. Both the input and output stanchions 302a,b may be
electrically conductive or otherwise made of a material that is
able to conduct an electrical current. The second post 216b may or
may not be electrically conductive. In embodiments where the second
post 216b is electrically conductive, any voltages applied across
the second post 216b may be prevented from passing through and into
the circuit board 204.
[0041] In some embodiments, the filament wire 214 may be soldered,
welded, or brazed to one or both of the input and output stanchions
302a,b. In other embodiments, the filament wire 214 may be fastened
to one or both of the input and output stanchions 302a,b using one
or more mechanical fasteners such as, but not limited to, screws,
clamps, wedges, rivets, clips, combinations thereof, and the like.
In yet other embodiments, the filament wire 214 may form an
integral part of one or both of the input and output stanchions
302a,b. Moreover, one or both of the input and output stanchions
302a,b may include or otherwise define a portion of the first
lateral extension 226a. In the illustrated embodiment, each of the
input and output stanchions 302a,b are shown as defining
corresponding portions of the first lateral extension 226a.
[0042] In the illustrated embodiment, the first voltage 227 may be
conveyed to the input stanchion 302a via the first conductor line
230a. The input stanchion 302a may apply the first voltage 227
across the filament wire 214 and, more particularly, to a first
portion 304a of the filament wire 214 that extends from the input
stanchion 302a, across the housing 202, and to the second post
216b. The filament wire 214 may then loop around the second post
216 such that the first voltage 227 is conveyed back to the first
post 216a or, more particularly, to the output stanchion 302b via a
second portion 304b of the filament wire 214. More particularly,
the second portion 304b may be configured to extend from the second
post 216b, across the housing 202, and to the output stanchion
302b. The output stanchion 302b may convey the first voltage 227
downstream, such as to ground, for example.
[0043] As briefly discussed above, the filament wire 214 may be
manufactured or otherwise configured to exhibit a predetermined
resistance per unit length, and the first voltage 227 may be a
predetermined voltage used to overcome the predetermined resistance
of the filament wire 214. As a result, as the first voltage 227 is
conducted through the filament wire 214, the filament wire 214 may
be configured to burn, disintegrate, or otherwise fail, thereby
freeing the plunger 206 to move into its extended configuration, as
depicted in FIG. 3B.
[0044] Those skilled in the art will readily appreciate that
looping the filament wire 214 around the second post 216 via the
first and second portions 304a,b of the filament wire 214 requires
the first voltage 227 to traverse a greater effective length of the
filament wire 214. Increasing the effective length of the filament
wire 214 may increase its resistance such that a reduced amount of
voltage would be required to burn or otherwise disintegrate the
filament wire 214.
[0045] Moreover, looping the filament wire 214 around the second
post 216 via the first and second portions 304a,b also offers an
increased amount of strength for the filament wire 214 such that
the filament wire 214 may be better able to sustain vibrations and
other shock loading that may be encountered in a downhole
environment.
[0046] Referring now to FIGS. 4A-4D, with continued reference to
the prior figures, illustrated are exemplary embodiments of the
plunger 206, according to one or more embodiments. Each of the
variations of the plunger 206 in FIGS. 4A-4D may be used in
conjunction with any of the embodiments of the switches 200, 300
described above. As illustrated, in some embodiments of the plunger
206, the filament wire 214 may include two lengths of wire, each of
which may be configured to apply voltage in either the same or
opposing directions across the plunger 206. Accordingly, in at
least one embodiment, the filament wire 214 depicted in FIGS. 4A-4D
may be the first and second portions 304a,b of the filament wire
214, as described above with reference to FIGS. 3A and 3B. In other
embodiments, such as is shown in FIG. 4D, the filament wire 214 may
encompass a single wire strand that extends across the plunger
206.
[0047] In FIG. 4A, the at least one groove 218 may be centrally
defined or otherwise formed on the head 208 of the plunger 206. The
filament wire 214 may rest within or otherwise be restrained within
the groove 218 until burned or disintegrated, as described above.
As depicted, the groove 218 may be in the general shape of a
rectangular cut or slot defined in the head 208. In other
embodiments, however, the groove 218 may be arcuate in shape (i.e.,
"U" shaped), such that the filament wire 214 rests in a trough-like
structure. In yet other embodiments, the groove 218 may be "V"
shaped or assume any other polygonal shape capable of receiving or
otherwise containing the filament wire 214.
[0048] In FIG. 4B, the groove 218 may be entirely omitted from the
plunger 206, and the filament wire 214 may instead rest or
otherwise extend across the top of the head 208. In FIG. 4C, the at
least one groove 218 may be characterized as one or more
perforations or conduits defined in and otherwise extending through
the head 208 of the plunger 206. As illustrated in FIG. 4C first
and second conduits 402a and 402b may each be configured to receive
a separate strand of the filament wire 214 therethrough. As will be
appreciated, more or less than two conduits 402a,b may be used,
without departing from the scope of the disclosure. For instance,
in FIG. 4D, a single perforation or conduit 404 may be defined in
and otherwise extended through the head 208 of the plunger 206. As
illustrated, the conduit 404 may be configured to receive the
filament wire 214 therein.
[0049] Those skilled in the art will readily recognize several
other variations that the plunger 206 may assume while remaining
within the scope of the present disclosure. The embodiments
depicted in FIGS. 4A-4D are shown and described for illustrative
purposes only and therefore should not be considered as limiting
the disclosure to only those illustrated embodiments. Indeed, other
configurations of the plunger 206, not necessarily depicted or
otherwise described herein, but nonetheless configured to generally
interact with the filament wire 214 as discussed herein, are also
contemplated as being within the scope of the disclosure.
[0050] Therefore, the disclosed systems and methods are well
adapted to attain the ends and advantages mentioned as well as
those that are inherent therein. The particular embodiments
disclosed above are illustrative only, as the teachings of the
present disclosure may be modified and practiced in different but
equivalent manners apparent to those skilled in the art having the
benefit of the teachings herein. Furthermore, no limitations are
intended to the details of construction or design herein shown,
other than as described in the claims below. It is therefore
evident that the particular illustrative embodiments disclosed
above may be altered, combined, or modified and all such variations
are considered within the scope and spirit of the present
disclosure. The systems and methods illustratively disclosed herein
may suitably be practiced in the absence of any element that is not
specifically disclosed herein and/or any optional element disclosed
herein. While compositions and methods are described in terms of
"comprising," "containing," or "including" various components or
steps, the compositions and methods can also "consist essentially
of" or "consist of" the various components and steps. All numbers
and ranges disclosed above may vary by some amount. Whenever a
numerical range with a lower limit and an upper limit is disclosed,
any number and any included range falling within the range is
specifically disclosed. In particular, every range of values (of
the form, "from about a to about b," or, equivalently, "from
approximately a to b," or, equivalently, "from approximately a-b")
disclosed herein is to be understood to set forth every number and
range encompassed within the broader range of values. Also, the
terms in the claims have their plain, ordinary meaning unless
otherwise explicitly and clearly defined by the patentee. Moreover,
the indefinite articles "a" or "an," as used in the claims, are
defined herein to mean one or more than one of the element that it
introduces. If there is any conflict in the usages of a word or
term in this specification and one or more patent or other
documents that may be incorporated herein by reference, the
definitions that are consistent with this specification should be
adopted.
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