U.S. patent application number 12/330619 was filed with the patent office on 2010-06-10 for shaped charge with an integral liner and case.
This patent application is currently assigned to SCHLUMBERGER TECHNOLOGY CORPORATION. Invention is credited to Allan W. King.
Application Number | 20100139515 12/330619 |
Document ID | / |
Family ID | 42229611 |
Filed Date | 2010-06-10 |
United States Patent
Application |
20100139515 |
Kind Code |
A1 |
King; Allan W. |
June 10, 2010 |
SHAPED CHARGE WITH AN INTEGRAL LINER AND CASE
Abstract
An integral shaped charge has a liner portion and a case
portion, the liner portion forming a cavity extending from a face
to an apex. An explosive is disposed in the chamber.
Inventors: |
King; Allan W.; (Manvel,
TX) |
Correspondence
Address: |
Schlumberger Reservoir Completions;Schlumberger Technology Corporation
14910 Airline Road
Rosharon
TX
77583
US
|
Assignee: |
SCHLUMBERGER TECHNOLOGY
CORPORATION
SUGAR LAND
TX
|
Family ID: |
42229611 |
Appl. No.: |
12/330619 |
Filed: |
December 9, 2008 |
Current U.S.
Class: |
102/309 ;
86/20.1 |
Current CPC
Class: |
F42B 1/024 20130101;
F42B 1/036 20130101 |
Class at
Publication: |
102/309 ;
86/20.1 |
International
Class: |
F42B 1/036 20060101
F42B001/036; F42B 3/08 20060101 F42B003/08 |
Claims
1. A shaped charge comprising: a liner portion and a case portion
formed by one of the group of stamping, drawing and machining,
wherein the case portion and the liner portion are a single unitary
piece of shaped charge material; the case portion and the liner
portion defining a chamber between the case portion and the liner
portion; and an explosive material disposed within the chamber.
2. The shaped charge of claim 1, wherein the shaped charge material
comprises barite.
3. The shaped charge of claim 1, wherein the shaped charge material
comprises at least one selected from the group consisting of: a
metal, a glass, and a ceramic.
4. The shaped charge of claim 1, wherein the explosive material
comprises a first explosive material and a second explosive
material, the first and second explosive materials having different
explosive characteristics from one another.
5. The shaped charge of claim 1, wherein the shaped charge material
includes an explosive material.
6. The shaped charge of claim 1, wherein the liner portion extends
from a face of the shaped charge to an apex and comprises at least
three distinct radiuses of curvature.
7-8. (canceled)
9. The shaped charge of claim 1, wherein the explosive material
comprises a first PBX explosive material and a second PBX explosive
materials, the first and the second explosive materials having
different explosive characteristics.
10. The shaped charge of claim 1, wherein the explosive material is
PBX explosive.
11. The shaped charge of claim 1, wherein a liner insert is
disposed in a cavity defined by the liner portion.
12. The shaped charge of claim 1, wherein the liner insert
comprises a material selected from a group consisting of a metal, a
glass, a ceramic and barite.
13. The shaped charge of claim 11, wherein the liner insert
comprises sintered tungsten.
14. A method for constructing a shaped charge, the method
comprising the steps of: providing a single unified piece of shaped
charge material; forming the shaped charge material into a shaped
charge body comprising a liner portion and a case portion, wherein
forming comprises one selected from a group consisting of stamping,
drawing, and machining; and disposing an explosive material in the
shaped charge.
15. The method of claim 14, wherein the step of forming comprises
drawing the shaped charge material from a face around the case
portion to form the liner portion.
16. The method of claim 14, wherein the step of forming includes:
creating a generally conical shaped liner portion extending from a
face to an apex; and creating a case portion extending down and
around from the face proximate to the apex.
17. The method of claim 16, wherein the step of creating the
generally conical shaped liner portion precedes the step of
creating the case portion.
18. The method of claim 16, wherein the explosive material is
disposed with the perforating material before the shaped charge
body is formed.
19. The method of claim 16, wherein the explosive material is
disposed in a chamber defined by the liner and the case.
20. The method of claim 14, wherein the single unified piece of
shaped charge material is provided in a substantially flat planar
shape.
21. The method of claim 14, wherein the single unified piece of
shaped charge material is provided in a substantially flat planar
shape.
22. A method for constructing a shaped charge for a perforating
gun, comprising: providing a substantially planar, disk shaped
unitary piece of shaped charge material having a face; forming a
conically shaped liner portion extending from the face to an apex,
the liner portion having a cavity; drawing the shaped charge
material down from the face and around the liner portion to form a
case portion and a chamber between the liner portion and the case
portion; and disposing an explosive material in the chamber.
23. The method of claim 22, wherein the liner portion comprises at
least three distinct radiuses of curvature.
Description
TECHNICAL FIELD
[0001] The present specification relates in general to wellbore
operations and more specifically to shaped charges.
BACKGROUND
[0002] A perforating device or perforating gun may be utilized in a
subterranean well to perforate a well casing and surrounding
formation. For example, once a well is drilled, a well casing may
be inserted into the well and cemented into place. A perforating
gun may be inserted into the well and shaped charges may be
detonated to punch holes in the well casing and surrounding
formation. A shaped charge may include a liner surrounded by a case
to enclose explosive materials. When the explosive materials are
detonated in shaped charges, the liner portion forms a slug and a
jet that is propelled through the well casing and into the
formation and may create a perforation tunnel. Heretofore, the
liner and the case for the shaped charges are manufactured
separately utilizing two or more different non-integral or
non-unitary parts for the case and the liner.
SUMMARY
[0003] An embodiment of a shaped charge includes a shaped charge
comprising: a body comprising a liner portion and a case portion;
the case portion and the liner portion together being a single
unitary piece of shaped charge material; the case portion and the
liner portion defining a chamber between the case portion and the
liner portion; and an explosive material disposed within the
chamber.
[0004] The foregoing has outlined some of the features and
technical advantages of embodiments in order that the detailed
description of the embodiments that follow may be better
understood. Additional features and advantages will be described
hereinafter which form the subject of the claims herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The foregoing and other features and aspects of embodiments
will be best understood with reference to the following detailed
description of specific embodiments, when read in conjunction with
the accompanying drawings, wherein:
[0006] FIG. 1 is a schematic illustrating a perforating gun
disposed in a wellbore;
[0007] FIG. 2 is a cross-sectional view of an illustrative
embodiment of a shaped charge;
[0008] FIG. 3 and 4 are partial cross-sectional views of an
embodiment of a shaped charge at stages of a process of forming a
shaped charge; and
[0009] FIG. 5 is a cross-sectional view of another embodiment of a
shaped charge utilizing multiple explosive materials.
DETAILED DESCRIPTION
[0010] Refer now to the drawings wherein depicted elements are not
necessarily shown to scale and wherein like or similar elements are
designated by the same reference numeral through the several
views.
[0011] FIG. 1 is a well schematic illustrating an embodiment of a
perforating gun 5 disposed in a wellbore 7. Perforating gun 5 is
disposed in wellbore 7 on a conveyance 9 at subterranean formation
11. Perforating gun 5 includes one or more shaped charges 10
adapted for forming perforations and fluid communication between
wellbore 7 and formation 11. The conveyance 9 can be coiled tubing,
wireline, slickline, or production tubing, for example. Further,
the conveyance could be absent in a case where the perforating
device is integrated with a completion.
[0012] FIG. 2 is a cross-sectional view of an illustrative
embodiment of a shaped charge 10. Shaped charge 10 includes a body
12 and an explosive 14. Shaped charge body 12 is constructed of a
shaped charge material and includes a liner portion 16 and a case
portion 18. The liner portion 16 and the case portion 18 can be
formed of a single unitary piece of material of construction. For
example, in the embodiment illustrated in FIG. 2, shaped charge
body 12 is an integral shaped charge having a liner portion 16 and
a case portion 18 formed from a single unitary part of the shaped
charge material.
[0013] Liner portion 16 is a generally bowl, or coned, shaped
section that may shape the perforating jet of the detonated
explosive 14. For purposes of description, liner portion 16 forms a
cavity 20 extending from a face 22 of shaped charge 10 to a tip or
apex 24. Case portion 18 is the portion of body 12 that extends
around from face 22 proximate to apex 24. Explosive 14 is disposed
in a chamber 26 formed between liner portion 16 and case portion
18.
[0014] A hole 28 may be formed through case portion 18 into chamber
26. Hole 28 may be utilized, for example, for disposing explosive
14 in chamber 26 and for positioning and/or exposing a primer 30
(FIGS. 4 and 5). In the embodiment illustrated in FIG. 2, liner
portion 16 and case portion 18 are formed from a single unitary
piece of material. The single unitary piece of material can begin
as a substantially flat planar shape, and can preferably begin as a
flat circular disk shape.
[0015] An embodiment of a method of constructing a shaped charge 10
of the present invention is described with reference to FIGS. 3 and
4. In FIG. 3, a single piece of unitary material 32, referred to
herein as shaped charge material, is provided. Liner portion 16 and
case portion 18 may be constructed of various types of material
without departing from the scope of embodiments described herein.
For example, in this embodiment, material 32 may be formed of
various materials, including without limitation, metals, barite,
metal alloys, metal powders, ceramics, metal filled resins, and the
like. Barite can also be used when combined with a densifying agent
such as ceramics, glass, steel, lead etc or other metal powder. As
will be further understood, material 32 may include explosive
material 14.
[0016] In this embodiment, material 32 is provided as a
substantially planar member that is a single unitary part and is
circular in shape. In a first step, liner portion 16 is formed from
the material 32 into substantially the desired profile and
dimensioned to achieve the desired liner portion 16 shape. For
example, in this embodiment, liner portion 16 is formed to have a
triple radius formed as it extends down from a face 22 down to its
tip 24. For example, there can be at least three distinct radiuses
of curvature from the face 22 to the tip 24, possibly as part of a
progressive change of curvature, akin to tapering. Ballistic
characteristics can be affected from varying the shape of the liner
portion. Further, as in this embodiment liner portion 16 can have a
progressively changing thickness, e.g., tapering, wherein its
thickness decreases as it extends from about face 22 toward tip 24.
Similarly, the thickness of the liner will affect ballistics
characteristics. Material 32 may then be drawn down and around the
liner portion 16 to form a case portion 18 to define chamber 26 as
shown in FIG. 4.
[0017] Explosive 14 may be provided prior to or after shaped charge
body 12 is formed and shaped into the desired liner portion 16 and
case portion 18 configuration. For example, in some embodiments,
explosive 14, such as plastic bonded explosive (PBX), may be
injected or extruded into chamber 26. In the embodiment of FIG. 3,
explosive material 14 is illustrated as being disposed with
material 32 along the portion forming liner portion 16 prior to
forming case portion 18. Thereby, when case portion 18 is formed
(FIG. 4) explosive 14 is positioned in chamber 26. A liner insert
34 may be disposed in liner cavity 20.
[0018] Shaped charge body 12 may be formed in various manners
associated with the composition of material 32. For example, if
shaped charge material is a metal, liner portion 16 may be formed
from the sheet of material by stamping, drawing, casting,
machining, molding, or by any suitable manufacturing method.
However, in other embodiments, the materials may be provided in any
suitable form for the particular manufacturing method utilized,
such as a liquefied material for casting, a solid block of material
for machining, and the like. Further, the material utilized to form
the shaped charge may be a metal or a combination of metals, a
metal filled resin, a ceramic, glass, barite, refractory material,
any other suitable materials, or a combination thereof Barite can
also be used when combined with a densifying agent such as
ceramics, glass, steel, lead etc or other metal powder.
[0019] FIG. 5 is a cross-sectional view of another embodiment of a
shaped charge 10 having an integral shaped charge body 12 (a liner
portion 16 and a case portion 18) and multiple explosive materials
90a and 90b. In the illustrated embodiment, shaped charge 10
includes a first explosive material 90a and a second explosive
material 90b. For example, second explosive 90b may have a higher
velocity of detonation (VOD) than first explosive 90a. In some
embodiments, explosives 90a and 90b may be injected or extruded
into chamber 26 after shaped charge body 12 is formed. In other
embodiments, explosives 90a and 90b may be disposed with shaped
charge material 32 (FIG. 3) prior to forming shaped charge body 12.
Shaped charge 10, illustrated in FIG. 5, further includes an inert
resin spider 36 and a primer 30 disposed in chamber 26. The primer
30 can extend along the inside of the case portion 18 outward and
upward from the hole 28, and end with a primer ring 31 at the rim
of the primer 30.
[0020] From the foregoing detailed description of specific
embodiments, it should be apparent that apparatuses, systems, and
methods of manufacturing shaped charges that are novel have been
disclosed. Although specific inventive embodiments have been
disclosed herein in some detail, this has been done solely for the
purposes of describing various inventive features and aspects, and
is not intended to be limiting with respect to the scope of the
claims herein. It is contemplated that various substitutions,
alterations, and/or modifications, including but not limited to
those embodiment variations which may have been suggested herein,
may be made to the disclosed embodiments without departing from the
spirit and scope of the specification and the claims herein.
* * * * *