Information
-
Patent Grant
-
6405628
-
Patent Number
6,405,628
-
Date Filed
Tuesday, August 17, 199925 years ago
-
Date Issued
Tuesday, June 18, 200222 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 086 2015
- 086 50
- 089 115
- 175 2
- 175 45
- 175 457
- 102 365
- 102 438
- 102 439
- 102 440
- 102 473
- 102 489
- 102 522
- 102 313
- 102 314
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International Classifications
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Abstract
A method and apparatus for drilling and penetrating hard materials utilizes a high velocity gun system that fires multiple shots of a projectile and an energetic slurry at the surface of the material to be penetrated. The penetrating device includes one or more firing barrels that are loaded with a propellant, a projectile and an energetic (explosive) slurry, and are controlled to fire in a preselected firing sequence. The projectile enters the material to be penetrated generating a hole into which the energetic slurry is also fired. The energetic slurry detonates upon contact with the material causing an explosion that further fractures the material and which blows the material out of the hole. The process is repeated until a desired penetration depth is obtained.
Description
FIELD OF THE INVENTION
The present invention is directed in general to a method and apparatus for drilling or penetrating hard surfaces and materials such as rock, concrete and steel. In particular, the present invention is directed to penetrating hard surfaces and materials utilizing a high velocity gun system that fires multiple shots of a projectile and an energetic slurry at the surface of the material to be penetrated.
BACKGROUND OF THE INVENTION
Conventional excavation techniques employ the use of drills to drill holes in a layer of a material to be penetrated. Explosives are placed in the holes and detonated to cause a layer of the material to fracture and break apart. The resulting rubble is cleared from the excavation site and the process is repeated for a subsequent layer of material to be penetrated. Such conventional excavation techniques result in a slow and tedious process in which several distinct and separate steps must be performed in sequence to excavate each layer of material to be removed.
Convention drilling or boring techniques employ the use of complicated mechanical drilling apparatus. The drilling apparatus incorporates the use of a drill bit to cut through the material being bored. Mechanical drill bits are subject to wear and breakage, however, and therefore must be periodically maintained or replaced. The required maintenance of mechanical drilling apparatus generally increases in proportion to the hardness of the material to be drilled, causing delays and interruptions in the drilling process in order to service the drilling equipment.
In view of the above, it would be desirable to provide a method and apparatus for boring through and excavating hard materials such as rock, concrete and steel that would allow for the rapid removal of material without requiring the separate steps of drilling, placement of explosives, detonation of explosives and debris removal associated with conventional excavation techniques or the use of maintenance prone and mechanically complicated drilling systems associated with conventional drilling or boring techniques.
SUMMARY OF THE INVENTION
The invention provides a method and apparatus for drilling and penetrating hard materials utilizing a high velocity gun system that fires multiple shots of a projectile and an energetic slurry at the surface of the material to be penetrated. More specifically a penetrating device is provided that includes one or more firing barrels. The firing barrels are loaded with a propellant, a projectile and an energetic (explosive) slurry, and are controlled to fire in a preselected firing sequence. The projectile enters the material to be penetrated generating a hole into which the energetic slurry is also fired. The energetic slurry detonates upon contact with the material causing an explosion that further fractures the material and which blows the material out of the hole. The process is repeated until a desired penetration is obtained.
In preferred embodiments, the projectile includes aluminum which reacts with the slurry to further enhance the explosive force, the slurry preferably includes at least one of HMX, RDX and TNT, and the propellant is a preferably a liquid propellent of a type used in conventional liquid propellant guns although conventional solid propellents may be employed. Still further, the device is preferably provided with an explosive payload that is detonated when the desired penetration depth is reached. In a still further embodiment, the device is fitted with control fins and a guidance system for use as an air launched munitions.
Additional features and advantages of the invention will become apparent to those of ordinary skill in the art after review of the following detailed description of the preferred embodiments of the invention with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described with reference to certain preferred embodiments thereof as shown in the accompanying drawings, wherein:
FIG. 1
illustrates a basic penetrating device in accordance with the invention that utilizes a single firing barrel;
FIG. 2
illustrates the penetration of a material by a projectile fired by the penetrating device illustrated in
FIG. 1
;
FIG. 3
illustrates the detonation of an energetic slurry fired into a material by the penetrating device illustrated in
FIG. 1
;
FIG. 4
illustrates the dislodgement of material caused by the detonation of the energetic slurry as illustrated in
FIG. 3
;
FIG. 5
illustrates a man portable penetrating device in accordance with the present invention that includes three firing barrels;
FIG. 6
illustrates a drilling or boring penetrating device in accordance with the present invention that includes multiple firing barrels;
FIG. 7
illustrates a stand for holding the drilling device illustrated in
FIG. 6
in a substantially perpendicular position on a material to be bored;
FIG. 8
illustrates the generation of a bore hole by the firing of multiple projectiles by the device illustrated in
FIG. 6
;
FIG. 9
illustrates the detonation of energetic slurry fired into a bore hole by the device illustrated in
FIG. 6
;
FIG. 10
is a longitudinal cross-sectional view of a preferred embodiment of a projectile to be used in the device illustrated in
FIG. 6
;
FIG. 11
is a cross-sectional view of the projectile illustrated in
FIG. 10
taken along indicated line a—a;
FIG. 12
illustrates the creation of substantially stress fractures by the projectile illustrated in
FIG. 11
;
FIG. 13
illustrates a penetrating device of the type illustrated in
FIG. 6
further including an explosive payload;
FIG. 14
illustrates a penetrating device of the type illustrated in
FIG. 13
configured as an air launched munition; and
FIG. 15
illustrates a preferred number and pattern of firing barrels for a penetrating devices of the type illustrated in
FIGS. 6
,
13
and
14
.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION
FIG. 1
illustrates a basic penetrating device in accordance with the present invention that includes a firing barrel
10
through which a high velocity jet including a projectile
12
and a fixed volume of energetic slurry
14
is fired by combusting a propellant
16
. As shown in
FIG. 2
, the projectile
12
penetrates the surface of a material
18
to be excavated, thereby causing fractures
20
in the material that expand outward from a penetration hole
22
. The energetic slurry
14
follows the projectile
12
into the penetration hole
22
and achieves a fully coupled explosion within the penetration hole
22
(illustrated in FIG.
3
), which generates high pressure shock waves and hot gases that cause the fractured material (illustrated by the dashed line) to be blasted outward past the firing barrel
10
of the penetrating device. The penetration hole
22
is thereby cleared of debris during the penetration process as illustrated in FIG.
4
. Accordingly, the penetration process is made essentially continuous by firing the penetration device multiple times in rapid succession, with penetration and removal of material taking place without interruption, as successive shot causes the penetration hole
22
to be expanded.
The expendables utilized in the penetrating device include the energetic slurry
14
, the projectiles
12
, the propellant
16
and an obturator
15
located between the energetic slurry
14
and the propellant
16
. The energetic slurry
14
preferably includes an explosive material such as HMX, RDX or TNT, that is separated from the propellant
16
by the obturator
15
, which may be made of a plastic or any other suitable material. The projectiles
12
can be made of any desired material including metal or ceramics, depending upon the application and type of material to be penetrated. In a preferred embodiment, the projectiles
12
include at least some portion of aluminum which reacts with energetic slurry
14
to create a more powerful explosion. The projectile
12
can either be a single solid projectile, a projectile that splits into multiple pieces upon firing or multiple projectile elements such as steel shot. The propellant
16
is preferably a conventional liquid propellant utilized in conventional liquid propellant guns, thereby allowing the penetrating device to be easily recharged by pumping the projectiles
12
, the slurry
14
and the propellant
16
from pressurized tanks into the firing barrel
10
. The propellant
16
is ignited by conventional firing techniques utilized in various types of guns including electric ignition. Alternatively, solid propellant, for example conventional gun powder, can be utilized and the slurry
14
and projectiles
12
can be incorporated within a cartridge type device that essentially disintegrates upon ignition, in which case conventional mechanical type ammunition feeding systems can be utilized.
The penetration device can be easily made portable for use in demolition of walls or similar small structures. Referring to
FIG. 5
, a penetration device
26
in accordance with the invention is shown including a main body
28
mounted on a collapsible bipod
30
. The main body
28
incorporates three gun barrels
32
that fire a combination of energetic slurry and projectiles as described above in rapid succession. Alternatively, the penetration device can be mounted on a vehicle for further ease of mobility.
In a further embodiment illustrated in
FIG. 6
, the invention provides a penetration device
33
for boring deep into a material through the application of successive firings. The deep penetration device includes a fire control unit
34
, flexible containers
36
for storage of expendables including propellant, explosive slurry and projectiles, and a check valve system
38
for loading the expendables from the flexible containers into multiple firing barrels
40
. The fire control unit
34
controls the operation of the check valve system
38
to load and fire the multiple firing barrels
40
in a prescribed firing pattern, and may be implemented utilizing special purpose control processors, general purpose processors specifically programmed for the application, discrete circuit components or combinations thereof
As is illustrated in
FIG. 7
, the penetration device
33
is loaded into a firing stand
42
such that the penetration device
33
is substantially perpendicular to a surface of the material to be bored. The firing stand includes a holding tube
43
, in which the penetration device
33
is placed, and a number of support legs
45
. Upon activation, the fire control unit
34
controls the firing barrels
40
to fire projectiles and energetic slurry into the surface of the material. As illustrated in
FIG. 8
, the projectiles
12
fired from the gun barrels
40
penetrate the material drilling holes approximately three times their diameter and causing stress fractures
44
in the material. The energetic slurry
14
ignites upon hitting the bottom of the hole being bored, thereby generating high pressure gases that penetrate the stress fractures
44
(as shown in
FIG. 9
) and causing the fractured material to be blown past the firing barrels
40
. The weight of the penetrating device causes it to slide through the holding tube
43
and into the penetration hole formed by the excavation. The process is repeated causing the penetrating device
33
to progressively move deeper into the material to be bored, until a desired penetration depth is reached.
In order to maximize the efficiency of the penetrating device, it is desirable to utilize a projectile
12
that will both penetrate perpendicularly to a surface of the material to be penetrated, and will also cause stress fractures that run substantially parallel to surface of the material, so that the material can be easily blasted from the penetration hole by the gases and shock waves generated by the detonation of the energetic slurry
14
.
FIGS. 10 and 11
illustrate a preferred projectile that includes a Lexan™ sabot
46
, an aluminum pusher
48
, a steel ram
50
, four steel supplemental projectile elements
52
, a polyethylene buffer
54
and a steel nose primary projectile element
56
. Upon firing, the steel nose primary projectile element
56
penetrates substantially perpendicular to the surface of the material to be bored and generates radiating type stress fractures
58
. The supplemental projectile elements
52
separate and open like flower pedals to penetrate the material at oblique angles as illustrated in
FIG. 12
, causing their own stress fractures
60
that overlap the stress fractures
58
generated by the primary projectile element
56
. The cross-fracturing substantially weakens the material over single dimensional fractioning that would occur if all projectiles penetrated perpendicular to the surface. Accordingly, the detonation of the energetic slurry
14
causes a larger volume of the material to be removed (indicated by dashed line) as opposed to the results obtained from a single perpendicularly entering projectile.
The invention can be utilized for any number of applications. In one preferred embodiment, the penetrating device is further fitted with an explosive payload
62
, as shown in
FIG. 13
, that is detonated once the penetrating device has reached a specified depth. Still further, the penetrating device illustrated in
FIG. 13
can be further modified by the addition of control canards
64
, control fins
66
and a guidance system
68
into an air launched penetrating munitions, as illustrated in FIG.
14
. In this embodiment, the penetrating device is also provided with a stabilizing drag chute (not shown) to stabilize the device so that it hits the ground in a substantially vertical orientation. Prior to impact, a ground proximity sensor
70
is utilized to signal the control unit
34
to begin firing the firing barrels
40
just prior to impact, thereby creating a crater into which the device can penetrate.
The invention provides a number of advantages over conventional excavation and drilling techniques. For example, large amounts of material can be rapidly removed at relatively low cost. The device does not require complex mechanical support systems that are subject to failure or extensive maintenance. Further, the device can be remotely operated or preprogrammed for remote operation thereby avoiding potential injuries.
The invention has been described with reference to certain preferred embodiments thereof. It will be understood, however, that modifications and variations are possible within the scope of the appended claims. For example, the type of propellent, energetic slurry and projectile to be used will necessary be dependent on the application and material to be penetrated. The number and configuration of the firing barrels may also be varied. In general, the number and horizontal separation of the firing barrels determine the horizontal separation in the fractures formed in them material to be penetrated, while the projectile structure determines the depth.
FIG. 15
, for example, illustrates one preferred distribution of firing barrels, wherein six firing barrels are disposed at substantially equal intervals in a circle and a seventh barrel is provided at the center of the circle.
Claims
- 1. An apparatus comprising:a projectile and an energetic slurry at least one firing barrel; and firing means for firing the projectile and energetic slurry from the firing barrel; wherein said projectile includes a sabot, a pusher, a ram located adjacent the pusher, a plurality of supplemental projectile elements located adjacent to the ram, a buffer material located next to the supplemental projectile elements and a primary projectile element.
- 2. An apparatus as claimed in claim 1, wherein the firing means includes a liquid propellant.
- 3. An apparatus as claimed in claim 1, wherein the energetic slurry includes at least one of HMX, RDX and TNT.
- 4. An apparatus as claimed in claim 1, wherein the projectile includes aluminum.
- 5. An apparatus comprising:a plurality of firing barrels; supply means for supplying projectiles, an energetic slurry and a propellant into said firing barrels; and control means for controlling the firing of said plurality of firing barrels in accordance with a preselected firing sequence; wherein said projectile includes a sabot, a pusher, a ram located adjacent the pusher, a plurality of supplemental projectile elements located adjacent to the ram, a buffer material located next to the supplemental projectile elements and a primary projectile element.
- 6. An apparatus as claimed in claim 5, further comprising an explosive payload.
- 7. An apparatus as claimed in claim 6, further comprising control fins and a guidance system.
- 8. An apparatus as claimed in claim 5, wherein said projectile includes a primary projectile element and a plurality of secondary projectile elements.
- 9. An apparatus as claimed in claim 5, wherein said propellant comprises a liquid propellant.
- 10. An apparatus as claimed in claim 5, wherein the energetic slurry includes at least one of HMX, RDX and TNT.
- 11. An apparatus as claimed in claim 5, wherein the projectile includes aluminum.
- 12. A method of penetrating a material comprising the steps of:a. loading a firing barrel with a propellant, a projectile and an energetic slurry, wherein said projectile includes a sabot, a pusher, a ram located adjacent the pusher, a plurality of supplemental projectile elements located adjacent to the ram, a buffer material located next to the supplemental projectile elements and a primary projectile element; b. firing the loaded firing barrel at the material to be penetrated; and c. repeating steps a and b until a desired penetration is obtained.
- 13. A method as claimed in claim 12, wherein said propellant comprises a liquid propellant.
- 14. A method as claimed in claim 12, wherein the energetic slurry includes at least one of HMX, RDX and TNT.
- 15. A method as claimed in claim 12, wherein the projectile includes aluminum.
US Referenced Citations (10)
Foreign Referenced Citations (2)
Number |
Date |
Country |
2622156 |
Nov 1977 |
DE |
488236 |
Sep 1918 |
FR |