US2605704A - Pyrotechnical cutting apparatus - Google Patents
Pyrotechnical cutting apparatus Download PDFInfo
- Publication number
- US2605704A US2605704A US706639A US70663946A US2605704A US 2605704 A US2605704 A US 2605704A US 706639 A US706639 A US 706639A US 70663946 A US70663946 A US 70663946A US 2605704 A US2605704 A US 2605704A
- Authority
- US
- United States
- Prior art keywords
- explosive
- cavity
- charge
- cutting apparatus
- section
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000005520 cutting process Methods 0.000 title description 17
- 239000002360 explosive Substances 0.000 description 27
- 238000005474 detonation Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 4
- 238000010276 construction Methods 0.000 description 3
- 230000001788 irregular Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 235000003332 Ilex aquifolium Nutrition 0.000 description 1
- 241000209027 Ilex aquifolium Species 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 238000005422 blasting Methods 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000001066 destructive effect Effects 0.000 description 1
- 235000020004 porter Nutrition 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000037452 priming Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
- F42B1/00—Explosive charges characterised by form or shape but not dependent on shape of container
- F42B1/02—Shaped or hollow charges
Definitions
- the present invention has for its object a pyrotechnical apparatus specially adapted for pyrotechnical cutting-as. it is practiced in the enterprises of civil engineering and public works, by the apposition of a longitudinal set of explosives to the surface or wall to be out.
- Its particular object is to provide structures of cutting apparatus which will ensure an efficient cutting, superior to that of the usual practice, while at thesame time only employing a much smaller quantity of explosive.
- Devices according to the invention comprise an elongated cavity, provided in the explosive, according to a course orientated in the direction of propagation of the detonation wave within the explosive or in a neighboring direction, and opening on the side of the wall to be cut.
- the cutting effect is, besides, reinforced by the lining of said cavity with a wall made of metal or of a cast or agglomerate material, of a strong mechanical resistance, applied either directly on the surface of the explosive, or on an intermediate envelope containing said explosive.
- the cross section of said cavity substantially symmetrical with reference to a plane perpendicular to the plane of the surface to be cut, in other words, to the plane defined by its opening along the longitudinal section of the useful charge of the explosive (the section below which the concentration action of the detonation is no longer directed towards the surface to be out), can be either of any triangular, polygonal, or ourvilinear shape desired, but, in accordance with another feature.
- this cross-section when working with explosives having a high speed of detonation, this cross-section is so designed that the isosceles triangle inscribed, having for its apex the point of the normal maximum distance to the aforesaid plane of opening and for its base, the distance between the extreme points of application of the useful explosive charge in this section shows an angle at the apex Of between 90 and 120.
- the outer casing of the device if rigid, or the lining of the cavity, is lengthened by construction in the direction of the surface to be cut, in such a manner as to ensure, when the apparatus is put into place, a distance to said surface corresponding to the optimum efiiciency of the cutting charge employed; said distance being always less than about one and a half times the opening of the cavity.
- the structures of. the apparatus are made flexible or plastic longitudinally, while, at the same time, retaining practically the above men-.
- Fig. 1 shows, in perspective, a diagrammatical example of embodiment of such an apparatus
- Figs. 2 and 3 and Fig. 5 givein cross-section, two alternatives of the example shown in Fig. 1.
- Fig. 4 shows the limit of dimensioning provided for the cross-section of the cavity; and 7 Figs. 6 to 9 represent various alternatives of embodiment, incorporating some structural features specially designed to give a simple method of putting the invention into execution.
- This casing is lengthened by walls such as 5 and 6 which permit of obtaining by construction the optimum distance of action between the useful plane of the explosive charge and the planeof the surface to be out which distance is variable following the shape and nature of the charge I and the material of the surface to be cut, but which is less than one and a half times the transversalwidth of the cavity formed by said walls.
- walls such as 5 and 6 which permit of obtaining by construction the optimum distance of action between the useful plane of the explosive charge and the planeof the surface to be out which distance is variable following the shape and nature of the charge I and the material of the surface to be cut, but which is less than one and a half times the transversalwidth of the cavity formed by said walls.
- this distance can be defined'during the manufacturing process, not being calculated from the rigid lining of the cavity 3, but from the rigid casing surrounding the explosive charge.
- this crosssection is shown as an isosceles triangle with its apex upper A and laterals B and C. This triangular section .is not necessary, however, and
- linesAB and BC of the casing may be curved as shown, for'example an ogivel of apex A or even a semi-circular arch as is shown as an illustration in 8 of Fig. 3, where the section is a semi-circle with the diameter BC.
- the crosssection of the cavity which should preferably be symmetrical with respect to th longitudinal plane of the apparatus, should have such aform that the above-mentioned isosceles triangle with its points AB and C defined above,
- the walls of this cavity can then have any desired form, from the dihedral shape BAC to the cylindrical shape B1AC1, passing through any other curvilinear and (or) polygonal shape.
- tubes it is understood not only circular tubes but thoseof all forms of circular, elliptical, oval, or polygonal sections as desired. It is thus that in the, example shown in Fig. 6 the explosive I oocupies the space between an oval tube II which forms at the same time the outer casing and a tube of circular section I 2 which forms the wall of the cavity 3.
- the outside tube I3 is flattened at I4 in order to constitute a supporting wall on the surface to be cut, the cavity 3 being limited by a profiled element I5 having a V-shaped cross section.
- This element I5 is wedged in the tube I3 by the compressed powder behind it.
- the external casing I6 is made of a flexible sheath which is fixed around the tube I'I, limiting the cavity 3 and the explosive I, and holding them in their relative desirable positions. Structures of this type are specially interesting, from the sole point of view of efficiency, for the underwater employment of the cutting apparatus; in fact, it has been discovered that in the latter case it was necessary to keep the cavity 3 watertight, which was rendered easy to realize, owing to these shapes.
- this method of realization permits the simplification of putting into practice another feature of the invention, that of making flexible the cutting apparatus comprising a cavity in order to facilitate putting them into position and to increase their efliciency on curved or irregular surfaces. It is suflicient, in fact, to provide for flexible tubes, water-tight or not, and other flexible elements of any known convenient type, and to employ either a pulverulent or a plastic explosive, while keeping, at the same time, the degree of rigidity desirable for the wall of the cavity 3, and the extensions of this wall,-or of the casing, used to keep the required spacing between the cutting apparatus and the surface to be cut, for example, by making them of a plastic, moulded, 0r agglomerated material reinforced or not by a casing or by a metallic framework.
- the charge I will be plastic, whereas the lining 4 and the walls 5, 6 thereof will be flexible.
- the charge I may be pulverulent or plastic, the tubes II and I2 being flexible.
- Fig. 9 shows diagrammatically, such an arrangement in which the rigid elements IB, I9, 20 of a cross-section such as is shown in relation to Figs. 1 to 8, or derived from these examples, are provided with terminal faces 2i and 22, convex and concave respectively, which fitinto each other.
- the continuity of the whole is ensured for example, by a flexible sheath 23, or it can simply be realized by placing some elements, one after the other onto the cutting wall.
- an elongated explosive charge formed of a plurality of comparatively rigid units and a relatively flexible sheath encasing all said units, the contacting adjacent ends of said units being formed respectively concavely and convexly and having substantially identical radii, whereby flexing of said sheath will maintain a substantially unaltered area of contact between adjacent ones of said units, said charge being formed with a longitudinal groove along the entire length thereof, so as to concentrate the cutting effect of the charge when exploded.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Lining Or Joining Of Plastics Or The Like (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR921208T | 1945-11-07 |
Publications (1)
Publication Number | Publication Date |
---|---|
US2605704A true US2605704A (en) | 1952-08-05 |
Family
ID=9434373
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US706639A Expired - Lifetime US2605704A (en) | 1945-11-07 | 1946-10-30 | Pyrotechnical cutting apparatus |
Country Status (5)
Country | Link |
---|---|
US (1) | US2605704A (en(2012)) |
BE (1) | BE468966A (en(2012)) |
FR (1) | FR921208A (en(2012)) |
GB (1) | GB618617A (en(2012)) |
NL (1) | NL66224C (en(2012)) |
Cited By (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2763210A (en) * | 1953-01-06 | 1956-09-18 | Joseph H Church | Shaped charges |
US2833215A (en) * | 1951-08-18 | 1958-05-06 | Thomas C Bannon | Gun perforator and method of manufacture |
US3185089A (en) * | 1962-06-28 | 1965-05-25 | Thiokol Chemical Corp | Flexible linear shaped charge for underwater use |
US3280743A (en) * | 1963-05-10 | 1966-10-25 | Hubert G Reuther | Directional control of explosive energy |
US3561703A (en) * | 1969-07-07 | 1971-02-09 | Stencel Aero Eng Corp | Canopy breaking by shaped charge |
JPS4894981A (en(2012)) * | 1972-03-17 | 1973-12-06 | ||
US3934511A (en) * | 1968-08-15 | 1976-01-27 | The United States Of America As Represented By The Secretary Of The Navy | Linear shaped charge warhead |
US3991679A (en) * | 1975-06-23 | 1976-11-16 | The United States Of America As Represented By The Secretary Of The Navy | Booster apparatus for augmenting side initiation of explosive cords |
US4034672A (en) * | 1976-01-02 | 1977-07-12 | Eckels Robert E | Linear explosive |
FR2473402A1 (en) * | 1980-01-15 | 1981-07-17 | Alsetex Armement Etud | Pyrotechnical process for splitting concrete slab - uses chain of explosive charges with inverted V=section at definite centres along cut line |
US4297946A (en) * | 1978-12-05 | 1981-11-03 | Paton Boris E | Extended shaped charge and method of making same |
US4374495A (en) * | 1977-09-17 | 1983-02-22 | Thomanek Franz R | Warhead for antitank missiles featuring a shaped charge |
US4649825A (en) * | 1984-06-25 | 1987-03-17 | The United States Of America As Represented By The Secretary Of The Navy | Explosive separation system for composite materials |
EP0278233A1 (de) * | 1987-01-14 | 1988-08-17 | DIEHL GMBH & CO. | Gehäuse für koppelbare Schneidladungen |
AU600236B2 (en) * | 1979-08-14 | 1990-08-09 | Bae Systems Plc | Linear cutting charge |
US5111637A (en) * | 1988-09-26 | 1992-05-12 | Highland Supply Corporation | Method for wrapping a floral grouping |
US5239804A (en) * | 1988-09-26 | 1993-08-31 | Highland Supply Corporation | Method for wrapping a floral grouping |
US5522319A (en) * | 1994-07-05 | 1996-06-04 | The United States Of America As Represented By The United States Department Of Energy | Free form hemispherical shaped charge |
US5720344A (en) * | 1996-10-21 | 1998-02-24 | Newman; Frederic M. | Method of longitudinally splitting a pipe coupling within a wellbore |
US20050211467A1 (en) * | 2004-03-24 | 2005-09-29 | Schlumberger Technology Corporation | Shaped Charge Loading Tube for Perforating Gun |
US20060201373A1 (en) * | 2002-11-28 | 2006-09-14 | James Sammons | Linear shaped charge system |
AU2003283125B2 (en) * | 2002-11-28 | 2009-04-23 | Applied Explosives Technology Pty Limited | Improved linear shaped charge system |
US20100018427A1 (en) * | 2006-03-04 | 2010-01-28 | Alford Research Limited | Explosive Charge |
US8006621B1 (en) * | 2008-02-07 | 2011-08-30 | Cherry Christopher R | Linear explosive breaching apparatus and method |
US8146503B2 (en) | 2002-11-28 | 2012-04-03 | Rapid Entry Pty Limited | Linear shaped charge system |
CN104101273A (zh) * | 2014-07-21 | 2014-10-15 | 中国船舶重工集团公司第七○二研究所 | 一种基于水下爆炸技术的新型排爆装置 |
US8887609B1 (en) | 2009-02-27 | 2014-11-18 | Christopher R. Cherry | Explosive system for destruction of overpacked munitions |
RU2570148C1 (ru) * | 2014-07-01 | 2015-12-10 | Общество с ограниченной ответственностью "Газпром трансгаз Самара" | Подрывной заряд |
AU2016225950B2 (en) * | 2016-09-12 | 2018-09-27 | Applied Explosives Technology Pty Limited | Further Improved Linear Shaped Charge System |
US10969204B2 (en) * | 2018-01-11 | 2021-04-06 | The United States Of America, As Represented By The Secretary Of The Navy | Systems and methods for penetrating structures with repositionable shaped charges |
RU204402U1 (ru) * | 2020-05-19 | 2021-05-24 | Николай Павлович Михайлов | Удлиненный заряд взрывчатого вещества |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2513233A (en) * | 1949-03-15 | 1950-06-27 | Laud Stanley Byers | Multiple jet blasting charge |
US2973164A (en) * | 1949-05-13 | 1961-02-28 | Northrop Corp | Wing severing device |
US2789504A (en) * | 1950-02-25 | 1957-04-23 | Mccloud Mary | High explosives |
US2757611A (en) * | 1950-04-11 | 1956-08-07 | Joseph H Church | Shaped charges |
US2839997A (en) * | 1950-05-12 | 1958-06-24 | Joseph H Church | Shaped charges |
DE974557C (de) * | 1956-07-27 | 1961-02-09 | Wasagchemie Ag | Verfahren zur Lenkung und Verstaerkung der Wirkung von Sprengkoerpern |
GB2476992B (en) | 2010-01-18 | 2014-12-03 | Jet Physics Ltd | Linear shaped charge |
GB2476993B (en) | 2010-01-18 | 2015-02-11 | Jet Physics Ltd | A material and linear shaped charge |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB191128030A (en) * | 1910-12-14 | 1912-10-10 | Westf Anhaltische Sprengstoff | Improvement in Explosive Charges or Bodies. |
US1440601A (en) * | 1921-01-06 | 1923-01-02 | John R Holran | Explosive charge |
US1531555A (en) * | 1924-07-31 | 1925-03-31 | Joseph W Harris | Art of perforating and severing metals |
US2404440A (en) * | 1941-04-19 | 1946-07-23 | Clarence W Lothrop | Torpedo countermining device |
US2407093A (en) * | 1942-05-21 | 1946-09-03 | Gestion Et D Expl De Brevets S | Method and apparatus for cutting or punching sheet material |
US2409848A (en) * | 1943-03-10 | 1946-10-22 | Carnegie Illinois Steel Corp | Twin tube mine clearing snake |
US2543057A (en) * | 1946-04-30 | 1951-02-27 | Louis F Porter | Elongated flexible tubular explosive |
-
0
- NL NL66224D patent/NL66224C/xx active
- BE BE468966D patent/BE468966A/xx unknown
-
1945
- 1945-11-07 FR FR921208D patent/FR921208A/fr not_active Expired
-
1946
- 1946-10-30 US US706639A patent/US2605704A/en not_active Expired - Lifetime
- 1946-11-04 GB GB32739/46A patent/GB618617A/en not_active Expired
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB191128030A (en) * | 1910-12-14 | 1912-10-10 | Westf Anhaltische Sprengstoff | Improvement in Explosive Charges or Bodies. |
US1440601A (en) * | 1921-01-06 | 1923-01-02 | John R Holran | Explosive charge |
US1531555A (en) * | 1924-07-31 | 1925-03-31 | Joseph W Harris | Art of perforating and severing metals |
US2404440A (en) * | 1941-04-19 | 1946-07-23 | Clarence W Lothrop | Torpedo countermining device |
US2407093A (en) * | 1942-05-21 | 1946-09-03 | Gestion Et D Expl De Brevets S | Method and apparatus for cutting or punching sheet material |
US2409848A (en) * | 1943-03-10 | 1946-10-22 | Carnegie Illinois Steel Corp | Twin tube mine clearing snake |
US2543057A (en) * | 1946-04-30 | 1951-02-27 | Louis F Porter | Elongated flexible tubular explosive |
Cited By (36)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2833215A (en) * | 1951-08-18 | 1958-05-06 | Thomas C Bannon | Gun perforator and method of manufacture |
US2763210A (en) * | 1953-01-06 | 1956-09-18 | Joseph H Church | Shaped charges |
US3185089A (en) * | 1962-06-28 | 1965-05-25 | Thiokol Chemical Corp | Flexible linear shaped charge for underwater use |
US3280743A (en) * | 1963-05-10 | 1966-10-25 | Hubert G Reuther | Directional control of explosive energy |
US3934511A (en) * | 1968-08-15 | 1976-01-27 | The United States Of America As Represented By The Secretary Of The Navy | Linear shaped charge warhead |
US3561703A (en) * | 1969-07-07 | 1971-02-09 | Stencel Aero Eng Corp | Canopy breaking by shaped charge |
JPS4894981A (en(2012)) * | 1972-03-17 | 1973-12-06 | ||
US3991679A (en) * | 1975-06-23 | 1976-11-16 | The United States Of America As Represented By The Secretary Of The Navy | Booster apparatus for augmenting side initiation of explosive cords |
US4034672A (en) * | 1976-01-02 | 1977-07-12 | Eckels Robert E | Linear explosive |
US4374495A (en) * | 1977-09-17 | 1983-02-22 | Thomanek Franz R | Warhead for antitank missiles featuring a shaped charge |
US4297946A (en) * | 1978-12-05 | 1981-11-03 | Paton Boris E | Extended shaped charge and method of making same |
AU600236B2 (en) * | 1979-08-14 | 1990-08-09 | Bae Systems Plc | Linear cutting charge |
FR2473402A1 (en) * | 1980-01-15 | 1981-07-17 | Alsetex Armement Etud | Pyrotechnical process for splitting concrete slab - uses chain of explosive charges with inverted V=section at definite centres along cut line |
US4649825A (en) * | 1984-06-25 | 1987-03-17 | The United States Of America As Represented By The Secretary Of The Navy | Explosive separation system for composite materials |
EP0278233A1 (de) * | 1987-01-14 | 1988-08-17 | DIEHL GMBH & CO. | Gehäuse für koppelbare Schneidladungen |
US5111637A (en) * | 1988-09-26 | 1992-05-12 | Highland Supply Corporation | Method for wrapping a floral grouping |
US5239804A (en) * | 1988-09-26 | 1993-08-31 | Highland Supply Corporation | Method for wrapping a floral grouping |
US5522319A (en) * | 1994-07-05 | 1996-06-04 | The United States Of America As Represented By The United States Department Of Energy | Free form hemispherical shaped charge |
US5720344A (en) * | 1996-10-21 | 1998-02-24 | Newman; Frederic M. | Method of longitudinally splitting a pipe coupling within a wellbore |
US20060201373A1 (en) * | 2002-11-28 | 2006-09-14 | James Sammons | Linear shaped charge system |
AU2003283125B2 (en) * | 2002-11-28 | 2009-04-23 | Applied Explosives Technology Pty Limited | Improved linear shaped charge system |
US7536956B2 (en) * | 2002-11-28 | 2009-05-26 | Rapid Entry Pty Limited | Linear shaped charge system |
US8146503B2 (en) | 2002-11-28 | 2012-04-03 | Rapid Entry Pty Limited | Linear shaped charge system |
US7159657B2 (en) | 2004-03-24 | 2007-01-09 | Schlumberger Technology Corporation | Shaped charge loading tube for perforating gun |
US20050211467A1 (en) * | 2004-03-24 | 2005-09-29 | Schlumberger Technology Corporation | Shaped Charge Loading Tube for Perforating Gun |
US9746292B2 (en) | 2006-03-04 | 2017-08-29 | Alford Research Limited | Explosive charge |
US20100018427A1 (en) * | 2006-03-04 | 2010-01-28 | Alford Research Limited | Explosive Charge |
US8006621B1 (en) * | 2008-02-07 | 2011-08-30 | Cherry Christopher R | Linear explosive breaching apparatus and method |
US8887609B1 (en) | 2009-02-27 | 2014-11-18 | Christopher R. Cherry | Explosive system for destruction of overpacked munitions |
RU2570148C1 (ru) * | 2014-07-01 | 2015-12-10 | Общество с ограниченной ответственностью "Газпром трансгаз Самара" | Подрывной заряд |
CN104101273A (zh) * | 2014-07-21 | 2014-10-15 | 中国船舶重工集团公司第七○二研究所 | 一种基于水下爆炸技术的新型排爆装置 |
AU2016225950B2 (en) * | 2016-09-12 | 2018-09-27 | Applied Explosives Technology Pty Limited | Further Improved Linear Shaped Charge System |
US10900756B2 (en) | 2016-09-12 | 2021-01-26 | Applied Explosives Technology Pty Limited | Further improved flexible linear charge system |
AU2018282259B2 (en) * | 2016-09-12 | 2021-07-01 | Applied Explosives Technology Pty Limited | Further Improved Flexible Linear Charge System |
US10969204B2 (en) * | 2018-01-11 | 2021-04-06 | The United States Of America, As Represented By The Secretary Of The Navy | Systems and methods for penetrating structures with repositionable shaped charges |
RU204402U1 (ru) * | 2020-05-19 | 2021-05-24 | Николай Павлович Михайлов | Удлиненный заряд взрывчатого вещества |
Also Published As
Publication number | Publication date |
---|---|
GB618617A (en) | 1949-02-24 |
NL66224C (en(2012)) | |
FR921208A (fr) | 1947-04-30 |
BE468966A (en(2012)) |
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