WO2001094277A2 - Detonating cord and methods of making and using the same - Google Patents
Detonating cord and methods of making and using the same Download PDFInfo
- Publication number
- WO2001094277A2 WO2001094277A2 PCT/US2001/016642 US0116642W WO0194277A2 WO 2001094277 A2 WO2001094277 A2 WO 2001094277A2 US 0116642 W US0116642 W US 0116642W WO 0194277 A2 WO0194277 A2 WO 0194277A2
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- WO
- WIPO (PCT)
- Prior art keywords
- detonating cord
- explosive
- diluent
- microballoons
- velocity
- Prior art date
Links
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- TZRXHJWUDPFEEY-UHFFFAOYSA-N Pentaerythritol Tetranitrate Chemical compound [O-][N+](=O)OCC(CO[N+]([O-])=O)(CO[N+]([O-])=O)CO[N+]([O-])=O TZRXHJWUDPFEEY-UHFFFAOYSA-N 0.000 claims abstract description 18
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- PAWQVTBBRAZDMG-UHFFFAOYSA-N 2-(3-bromo-2-fluorophenyl)acetic acid Chemical compound OC(=O)CC1=CC=CC(Br)=C1F PAWQVTBBRAZDMG-UHFFFAOYSA-N 0.000 claims description 11
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- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 claims description 5
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- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol group Chemical group C1(=CC=CC=C1)O ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 abstract description 18
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- 238000005422 blasting Methods 0.000 description 9
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- XTFIVUDBNACUBN-UHFFFAOYSA-N 1,3,5-trinitro-1,3,5-triazinane Chemical compound [O-][N+](=O)N1CN([N+]([O-])=O)CN([N+]([O-])=O)C1 XTFIVUDBNACUBN-UHFFFAOYSA-N 0.000 description 3
- YSIBQULRFXITSW-OWOJBTEDSA-N 1,3,5-trinitro-2-[(e)-2-(2,4,6-trinitrophenyl)ethenyl]benzene Chemical compound [O-][N+](=O)C1=CC([N+](=O)[O-])=CC([N+]([O-])=O)=C1\C=C\C1=C([N+]([O-])=O)C=C([N+]([O-])=O)C=C1[N+]([O-])=O YSIBQULRFXITSW-OWOJBTEDSA-N 0.000 description 3
- SNIOPGDIGTZGOP-UHFFFAOYSA-N Nitroglycerin Chemical group [O-][N+](=O)OCC(O[N+]([O-])=O)CO[N+]([O-])=O SNIOPGDIGTZGOP-UHFFFAOYSA-N 0.000 description 3
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- UZGLIIJVICEWHF-UHFFFAOYSA-N octogen Chemical compound [O-][N+](=O)N1CN([N+]([O-])=O)CN([N+]([O-])=O)CN([N+]([O-])=O)C1 UZGLIIJVICEWHF-UHFFFAOYSA-N 0.000 description 3
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- DAGSRNAIARXJOQ-UHFFFAOYSA-N 1,2,3,4-tetranitro-9h-carbazole Chemical compound C1=CC=C2C3=C([N+]([O-])=O)C([N+]([O-])=O)=C([N+](=O)[O-])C([N+]([O-])=O)=C3NC2=C1 DAGSRNAIARXJOQ-UHFFFAOYSA-N 0.000 description 1
- RUPDGJAVWKTTJW-UHFFFAOYSA-N 2,3-dinitropyridine Chemical compound [O-][N+](=O)C1=CC=CN=C1[N+]([O-])=O RUPDGJAVWKTTJW-UHFFFAOYSA-N 0.000 description 1
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- WYTGDNHDOZPMIW-RCBQFDQVSA-N alstonine Natural products C1=CC2=C3C=CC=CC3=NC2=C2N1C[C@H]1[C@H](C)OC=C(C(=O)OC)[C@H]1C2 WYTGDNHDOZPMIW-RCBQFDQVSA-N 0.000 description 1
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- QXJJQWWVWRCVQT-UHFFFAOYSA-K calcium;sodium;phosphate Chemical compound [Na+].[Ca+2].[O-]P([O-])([O-])=O QXJJQWWVWRCVQT-UHFFFAOYSA-K 0.000 description 1
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D1/00—Blasting methods or apparatus, e.g. loading or tamping
-
- C—CHEMISTRY; METALLURGY
- C06—EXPLOSIVES; MATCHES
- C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
- C06B23/00—Compositions characterised by non-explosive or non-thermic constituents
- C06B23/002—Sensitisers or density reducing agents, foam stabilisers, crystal habit modifiers
- C06B23/003—Porous or hollow inert particles
-
- C—CHEMISTRY; METALLURGY
- C06—EXPLOSIVES; MATCHES
- C06C—DETONATING OR PRIMING DEVICES; FUSES; CHEMICAL LIGHTERS; PYROPHORIC COMPOSITIONS
- C06C5/00—Fuses, e.g. fuse cords
- C06C5/04—Detonating fuses
Definitions
- the present invention is concerned with detonating cord having a controlled energy release which is attained by incorporating a diluent into the explosive core of the cord to control the velocity of detonation of the core.
- the present invention is also concerned with a method of making the detonating cord, and a method of utilizing the detonating cord to effectuate desired cutting or rapturing of any structures, rock formations or the like while minimizing undesired ancillary damage.
- Detonating cord is, of course, well known in the art and comprises a solid core of high explosive encased in a protective jacket which is usually waterproofed, such as by being coated with a suitable synthetic polymeric (plastic) material.
- the solid core of high explosive is a compressed pulverulent explosive which may or may not be plastic-bonded.
- Detonating cords are made in various sizes (core diameters) conventionally measured in grains of explosive per unit length.
- a typical explosive core for detonating cord is pentaerythritol tet- ranitrate ("PETN”) and typical core sizes range from about 5 grains of explosive per linear foot of cord (“gr/ft”) to about 400 gr/ft.
- detonating cord for a small detonating cord, e.g., one containing about 5 gr/ft (1.1 g/m) of explosive, a particle size of about 20 microns diameter is suitable, whereas for a detonating cord of much larger diameter, e.g., a detonating cord of about 400 gr/ft (85.2 g/m), adequate propagation of the explosion along the length of the cord may be attained with a particle diameter size of from 100 to 200 microns.
- detonating cord is generally used to transfer an explosive signal to various components of a blasting setup.
- detonating cord may be utilized as a surface trunkline to impart a detonation signal to a series of down-hole fuses such as shock tube or other detonating cords.
- a series of down-hole fuses such as shock tube or other detonating cords.
- PETN is the usual choice of explosive for detonating cord, other explosives may be used.
- explosives such as cyclo-1,3,5- trimethyleiie-2,4,6-trinitramine (Cyclonite, or "RDX”) or cyclotetramethylene tetranitramine (Homocyclonite, or "HMX”) may be utilized for the core of the detonating cord.
- RDX cyclo-1,3,5- trimethyleiie-2,4,6-trinitramine
- HMX cyclotetramethylene tetranitramine
- HNS hexanitrostilbene
- TMC tetranitrocarbazol
- PYX bis picryoamino 3,5, dinitro pyridine
- tubular sheath which encloses the core of explosive material
- any suitable material or combinations thereof as is well known in the art, may be employed. Such sheaths are pliable enough to enable the detonating cord to be deployed in any desired pattern, wrapped around structural members, etc.
- the sheath may also be a rigid sheath such as that described in Patent Application Serial No. 09/645,276, filed on August 24, 2000 in the name of Mark E. Woodall et al for "Rigid Reactive Cord And Methods Of Use And Manufacture". That patent application de-scribes a detonating cord having a non-metal outer sheath which imparts a sufficient flexural modulus, e.g., of about 250,000 psi (17.236 x 10 2 MPa), which enables a 6-foot length of the cord to be sufficiently rigid to perforate and penetrate fly ash. This rigid-type cord finds use in removing fly ash from boiler tubes.
- This patent deals with a propellant grain composition for use in solid-fuel rocket engines and discloses an oxidizer first reactant encapsulated by a polymeric barrier coating and a re- ducer fuel second reactant disposed on the polymeric barrier coating, with a final polymeric coating placed over the entire propellant grain to yield a unitary metal fuel-oxidizer propellant grain structure for use as a solid rocket fuel.
- U.S. Patent 5,859,264 issued January 12, 1999 to K. Coupland et al is entitled "Explosive Compositions” and discloses emulsifiers for use in emulsion explosives comprising a continuous organic phase and a discontinuous aqueous phase. At column 2, lines 59-67, this patent discloses the use of glass or resin microspheres or other gas-containing particulate materials.
- wedges are placed in each borehole of a line of boreholes and each wedge is gradually mechanically loaded in order to develop an even tensile stress field along the web of stone extending between and connecting the row of boreholes, until the web fragments to cleave the rock mass.
- the dimension stone industry is concerned with cutting from rock formations in quarries stone which is sized for use in construction and for headstones, markers and the like.
- black powder was one of the original explosive materials used in boreholes for cleaving stone by blasting.
- Black powder has a very low velocity of detonation and a very low explosive output and shock energy. These characteristics are advantageous in reducing collateral damage to stone cut from rock formations.
- the disadvantages of black powder are safety problems which inhere in its use, because black powder is extremely sensi- tive to static, sparks and fire, making it extremely dangerous. Black powder is also de-activated by water, precluding its use in wet areas.
- Dynamite is nitroglycerine soaked into an absorbent material and packaged in a cylindrical cartridge.
- the velocity of detonation of dynamite about 4500 feet per second (about 1,372 meters per second), is slightly higher than that of black powder.
- Dynamite also has slightly more radial explosive output.
- the primary disadvantage of dynamite is the excruciating headaches experienced by personnel who handle nitroglycerine-based material. Dynamite may also require a relatively large explosive diameter to function, rendering it unusable for smaller-diameter boreholes.
- a reduction in peak shock wave output pressure i.e., a reduction in the peak amplitude of the shock energy released by detonation of the cord, has been found to be highly beneficial in some applications where high-amplitude shock energy may cause or exacerbate unwanted collateral damage. Such applications include certain construction and tunneling activities, quarrying operations and cutting structures such as dimension stone, as described more fully below.
- a detonating cord having a controlled velocity of detonation and comprising a solid core of an explosive containing therein a first explosive and one or more diluents which reduce the velocity of deto- nation of the core.
- the detonating cord of the present invention finds use in any application in which reduced peak shock energy is required or desired.
- Reference herein to "reduced-velocity detonating cord”, “low-velocity detonating cord”, or the like, means a detonating cord whose explosive core contains a diluent which re- prises the velocity of detonation of the detonating cord as compared to an otherwise identical detonating cord which does not contain the diluent.
- the diluent may be either an explosively inert material, such as closed-cell void materials (referred to herein as microballoons, e.g., glass or resin microballoons or very fine plastic or glass beads, etc., or it may be an explosive material, for example, ammonium nitrate.
- closed-cell void materials referred to herein as microballoons, e.g., glass or resin microballoons or very fine plastic or glass beads, etc.
- an explosive material for example, ammonium nitrate.
- reference to a "solid" core of explosive material means that the tubular sheath of the detonating cord is completely filled with the explosive material.
- the presence of microballoons dispersed in the explosive material provides enclosed voids therein, but as the explosive material substantially completely fills the enclosing tubular sheath, the core is nonetheless described as a solid core.
- a detonating cord comprising an elongate tubular sheath encasing a solid core of an explosive material, the explosive material being comprised of a first explosive and a diluent.
- the diluent is present in an amount which reduces the velocity of detonation of the detonating cord as compared to that of an otherwise identical detonating cord in which the explosive material contains no diluent.
- the diluent comprises particles of an explosively inert material, e.g., explosively inert microballoons.
- the microballoons may be selected from the class consisting of glass microballoons and resin microballoons, preferably the latter, the microballoons having a diameter of from about 10 to about 175 microns.
- the microballoons may comprise resin microballoons, e.g., phenolic resin microballoons, having a diameter of from about 10 to about 175 microns.
- diluent comprises a second explosive material, e.g., ammonium nitrate, having a lower velocity of detonation than the first explosive material.
- a second explosive material e.g., ammonium nitrate
- the detonating cord contains from about 0.5 to 15%, e.g., from about 0.5 to 5%, by weight of the diluent, based on the dry weight of the core.
- the first explosive may be any suitable explosive, such as one or more of PETN, HMX, HNS, TNC, PYX and RDX.
- a method aspect of the present invention provides an improvement in a method of cleaving a rock formation. The method comprises drilling a plurality of substantially parallel boreholes into the formation to define between adjacent boreholes a web of rock interconnecting adjacent boreholes with each other, placing within the boreholes at least one length of deto- nating cord extending along the length of the respective boreholes, connecting the length of detonating cord to an explosive initiating device and initiating the length of detonating cord to cleave the formation.
- the improvement comprises that the detonating cord is one as described above.
- Another method aspect of the present invention provides a method for making a detonating cord as described above.
- the method comprises the steps of preparing an explosive material by admixing a first explosive with a diluent selected from the group consisting of (a) explosively inert diluents; (b) a second explosive having a velocity of detonation less than that of the first explosive; and (c) mixtures of (a) and (b), the diluent being present in an amount which reduces the velocity of detonation of the detonating cord as compared to an otherwise identical detonating cord in which the explosive material contains no diluent.
- the explosive material is enclosed within a tubular sheath to provide a detonating cord having a core of the explosive material.
- Figure 1 is a cross-sectional view in elevation of a segment of a slab of granite having a plurality of boreholes drilled therethrough;
- Figure 2 is a plan view of the granite slab of Figure 1 showing an end view of the boreholes
- Figure 3 is a schematic view corresponding to that of Figure 1 showing a length of detonating cord disposed within each of the boreholes and connected to a trunkline for initiation of the detonating cords;
- Figure 3 A is a cross-sectional view, enlarged relative to Figure 3, of a segment of the length of detonating cord illustrated in Figure 3;
- Figure 4 is a schematic view corresponding to that of Figure 1, but showing a stitching arrangement of a continuous length of detonating cord disposed as a loop within the boreholes;
- Figure 5 is a plan view of the granite slab of Figure 1 after it has been split in two by initiation of detonating cord emplaced with the boreholes;
- Figure 6 is a perspective, schematic view of a two-borehole setup for conducting tests of detonating cord;
- Figures 7-12 are graphs plotting the pressure output in thousands of pounds per square inch (“KLPS") against time in seconds of various samples of detonating cord tested in the setup illustrated in Figure 6.
- KLPS pounds per square inch
- the velocity of detonation of detonating cord can be controlled by mixing a diluent with the pulverulent explosive from which the explosive core of detonating cord is formed.
- the velocity of detonation of the detonating cord may be reduced. It has been discovered that by reducing the velocity of detonation, a reduction in the peak output pressures caused by detonation of the cord is attained without significantly affecting the total energy output of the cord.
- This smooth- wall technique is also employed in underground mining and tunneling applications to blast a secure, reasonably smooth roof or "back" in the mine, the smoothness of which reduces the requirements for mechanical supports such as roof bolts and the like.
- an explosive e.g., the use of detonating cord, of reduced velocity of detonation to cleave rock or stone along a line defined by a series of boreholes.
- Detonating cord is waterproof and safer to handle than black powder. It typically is a PETN-based explosive and produces none of the handling problems related to nitroglycerine-based explosives.
- Detonating cord can function in very small cord diameters, e.g., as small as less than 0.25 inch, i.e., 0.635 centimeter (“cm"), in diameter.
- These characteristics which are conventionally considered to be desirable attributes necessary to enable conventional detonating cord to initiate explosive charges of low sensitivity, contribute to excessive fracturing and cracking around the boreholes when conventional detonating cord is used to cleave rock. Only the detonating cord of the present invention provides an explosive of such small diameter, typically from about 0.125 to 0.250 inch (0.318 to 0.635 cm) diameter, having such a low velocity of detonation.
- Another aspect of the present invention utilizes a low- velocity detonating cord, preferably one having a velocity of detonation less than about 5000 meters per second ("m/sec").
- the invention enables taking advantage of the desirable features of detonating cord, such as the ability to be cut at any point along its length, and its relatively small cross-sectional diameter as compared to other explosives, with the feature of optimizing blasting performance by modifying the velocity of detonation of the cord.
- the low- velocity detonating cord of this aspect of the present invention results in decreased shock loading and increased gas pressurization within the boreholes in which the detonating cord is functioned, with no significant reduction in total energy output.
- the low- velocity detonating cord aspect of the present invention better mimics the action of mechanical wedges in cleaving stone than do conventional explosives, including conventional, high-velocity detonating cord, as is demonstrated by the data provided below. All of these advantages apply to any rock-cleaving application.
- the present invention permits the radial output energy of detonating cord to be tailored to a specific blasting application by changing, e.g., reducing, the velocity of detonation of the cord.
- FIG. 1 there is shown a somewhat schematic cross-sectional view taken along line I-I of Figure 2 of a granite block 10 having a plurality of boreholes 12 formed therein and extending substantially parallel to each other from and through top surface 14a to and through bottom surface 14b of granite block 10.
- parallel boreholes 12 are aligned along a straight line to define a web 16 of stone extending between and connecting boreholes 12 to each other.
- Web 16 is indicated in Figure 2 by dash lines.
- the present invention by providing an explosive which generates reduced peak shock wave pressures without a substantial reduction in total energy output, enhances the ability of the explosive of the present invention to break the rock web while reducing collateral radial damage to the rock. This enables increasing the spacing be- tween adj acent boreholes without a corresponding increase in collateral damage.
- Figure 3 shows schematically one arrangement for providing throughout the length of each of boreholes 12, lengths 18 of reduced- velocity detonating cord in accordance with an embodiment of the present invention.
- individual lengths 18 of reduced- velocity detonating cord are connected to a trunkline 20 which may itself comprise detonating cord and which may, but need not, be reduced- velocity detonating cord in accordance with an embodiment of the present invention.
- Trunkline 20 is initiated at one end thereof by any suitable known means (not illustrated) and a detonation signal travels along trunkline 20 to initiate each of the lengths 18 of detonating cord to fracture the web 16 of stone.
- FIG. 3 A shows that detonating cord 18 comprises a tubular sheath 18a encasing a solid core 18b of explosive material throughout which is dispersed a particulate diluent, provided in the illustrated embodiment by microballoons 18c.
- microballoons 18c is a hollow particulate body enclosing a void containing a gas, e.g., air.
- Tubular sheath 18a is made of any suitable material to provide adequate mechanical strength and to be resistant to penetra- tion of water or other liquids into core 18b.
- Figure 4 shows an alternate arrangement, sometimes referred to as "stitching", in which a single length 22 of reduced- velocity detonating cord in accordance with an embodiment of the present invention is threaded in a serpentine, stitching-like arrangement through each of boreholes 12 by inserting a return-loop of detonating cord through substantially the en- tire length of each borehole.
- Length 22 of detonating cord is initiated by any suitable means (not illustrated) and detonates along the length thereof to fracture the web 16 of stone.
- the total length of reduced-velocity detonating cord in a borehole is effectively doubled as compared to the arrangement of Figure 3.
- Adjacent the arcs 12a, 12b ( Figure 5) of the former boreholes 12 ( Figure 2) are a series of small radial cracks 24 and a few considerably longer radial cracks, refe ⁇ ed to as "stickers" in the dimension stone industry, shown at 26.
- the radial cracks 24 and stickers 26 be reduced in number and/or shortened as much as possible.
- a series of blocks was cleaved from larger blocks (production loaves) of granite using either 18 gr/ft (3.8 g/m), low- velocity detonating cord in accordance with an embodiment of the present invention, or conventional 18 gr/ft (3.8 g/m) detonating cord. All holes in the test blocks were loaded with Viking B-gel, an inert gel product with microballoons, available from Viking Explosives & Supply, Inc. of Rosemont, Minnesota.
- the B-gel is a product which is well known for use as a coupling agent for the purpose of buffering the initial shock pressure generated by functioning of the detonating cord. This or an equivalent gel product is used in an effort to reduce unwanted radial fracturing.
- a total of four blocks were cleaved using reduced- velocity detonating cord in accordance with an aspect of the present invention, and three blocks were cleaved using conventional high-velocity detonating cord. All blocks were sawed into 6 to 8 inch (about 15.2 to 20.3 cm) thick slabs and then polished. The yield from each slab, along with the degree of radial fracturing, was determined through observation and digital imaging analysis in order to compare the performance of each type of detonating cord. The observed results of these tests are tabulated in the following Table A. The average length of stickers was twelve inches. Table A
- the percents by weight are on the basis of percent by weight of the combined weight of PETN, ammonium nitrate and phenolic microballoons.
- the comparative detonating cord of Sample B had a loading of 18 gr/ft (3.83 g/m) of 100% PETN, i.e., it contained no diluent.
- Blast-pressure profiles were measured for a series of cord/coupling-agent combinations.
- the test arrangement is schematically illustrated in Figure 6 in which two test boreholes, 28 and 30, terminating in respective borehole bottoms 28a and 30a, were bored in the stone par- allel to each other with their peripheries spaced 6 inches (15.24 cm) from each other, this distance being illustrated as D in Figure 6.
- test detonating cord 32 was inserted throughout the length of test borehole 28 and, in those cases in which a coupling agent other than air was utilized, borehole 28 was filled with a coupling agent, e.g., gel or water (not shown).
- a coupling agent e.g., gel or water (not shown).
- a loop (not shown) of test detonating cord 32 was inserted into borehole 28 in order to test a "stitching" arrangement of detonating cord, as schematically illustrated in Figure 4.
- Test borehole 30 was filled with water as a coupling agent, and an underwater blast pressure sensor 34 was placed within the water-filled test borehole 30.
- Underwater blast pressure sensor 34 was connected by a cable 36 to computerized recording equipment (not illustrated) to record "pressure profiles", i.e., graphs of the pressure of the shock wave or pressure pulse generated by detonation of test detonating cord 32 as a function of time.
- the pressure profiles generated from test detonating cord 32 are shown in Figures 7-16, wherein the shock wave pressures are plotted on the left- hand vertical axes in kilopounds per square inch (“KIPS") and on the right-hand vertical axes in kilograms per square centimeter (“kg/cm 2 "). The time after functioning (detonation) is plotted on the horizontal axes in seconds.
- KIPS kilopounds per square inch
- kg/cm 2 kilograms per square centimeter
- the tested detonating cords 32 were 18 gr/ft (3.83 g/m) low- velocity cord in accordance with an embodiment of the present invention, and 7.5 gr/ft (1.60 g/m) and 18 gr/ft (3.83 g/m) comparative high-velocity cords.
- B-gel or air were used as the coupling agent.
- the energy output or work is indicated by the area beneath the curve in the Figures plotting the pressure profiles. These areas represent the product of pressure multiplied by time.
- FIG. 8 shows the pressure profile from comparative high- velocity detonating cord in B-gel coupling agent
- Figure 9 shows the pressure profile from low- velocity detonating cord in accordance with an embodiment of the present invention in B-gel coupling agent.
- a comparison of Figures 8 and 9 makes clear that the low- velocity detonating cord did not produce the sharp, high-amplitude pressure transients that were typical of the comparative high- velocity detonating cord, while otherwise maintaining a comparable level of pressure.
- the pressure profile of the low- velocity detonating cord in water shown in Figure 10 also shows that the reduction of the sharp peaks was not accompanied by a general reduction of pressure throughout the trace of the pressure profile.
- the performance of the low- velocity detonating cord in water shown in Figure 10 is of particular interest. It will be noted that these pressure profiles are very similar to those measured with low- velocity detonating cord in B-gel (shown in Figure 9) and represent a dramatic improvement over comparative high-velocity detonating cord in B-gel, shown in Figure 8. These results indicate that low- velocity cord in water performs better than the comparative high- velocity detonating cord' in B-gel, and about as well as low- velocity detonating cord in B-gel.
- FIG 11 A shows the pressure profile for a comparative high- velocity 18 gr/ft (3.83 g/m) detonating cord in air and a low-velocity 18 gr/ft (3.83 g/m) detonating cord in accordance with an embodiment of the present invention in air, the cords having been placed in the test borehole (28 in Figure 6) using the stitching arrangement schematically illustrated in Figure 4.
- Figure 12 shows the pressure profile of a comparative 7.5 gr/ft (1.60 g/m) high- velocity detonating cord in water as a coupling agent.
- the initial pressure peak while reduced as compared to higher core load detonating cords, is nonetheless prominent, about three times higher than the remaining non-peak pressure level.
- any suitable diluent may be utilized to reduce the velocity of the detonating cord, one which is found to be particularly useful is phenolic microballoons, e.g., of the type conventionally used as a filler in fiberglass resin applications to lower weight and density of finished fiberglass items.
- Phenolic resin is a brittle material and the addition of phenolic microballoons to the explosive core does not appear to sensitize dry PETN. Phenolic resin has a specific gravity of approximately 1.35 and the phenolic microballoons used had a tapped bulk density of 0.13 grams per cubic centimeter. (The container of phenolic microballoons is tapped on a solid surface to settle the material prior to measuring its density. The density of the settled material is referred to as its "tapped bulk density”.)
- the diluent may comprise an explosive diluent, such as ammonium nitrate, which is of significantly lesser brisance than the major explosive ingredient, e.g., PETN, of the detonating cord or other explosive used in the practices of the present invention.
- the explosive diluent may be used in combination with another diluent such as phenolic or other microballoons, or the explosive diluent or other type or types of non-explosive diluent, e.g., microballoons, may be used as the sole diluent.
- the phenolic microballoons used to prepare the tested low-velocity detonating cord had an average particle size distribution as follows, wherein ⁇ stands for microns.
- any suitable quantity of diluent may be used to attain a desired change, i.e., a reduction, in velocity of detonation.
- phenolic microballoons or other diluents
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
- Excavating Of Shafts Or Tunnels (AREA)
- Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA002410465A CA2410465C (en) | 2000-05-24 | 2001-05-23 | Detonating cord and methods of making and using the same |
AU2001292541A AU2001292541A1 (en) | 2000-05-24 | 2001-05-23 | Detonating cord and methods of making and using the same |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US20687700P | 2000-05-24 | 2000-05-24 | |
US60/206,877 | 2000-05-24 |
Publications (2)
Publication Number | Publication Date |
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WO2001094277A2 true WO2001094277A2 (en) | 2001-12-13 |
WO2001094277A3 WO2001094277A3 (en) | 2002-04-11 |
Family
ID=22768344
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2001/016642 WO2001094277A2 (en) | 2000-05-24 | 2001-05-23 | Detonating cord and methods of making and using the same |
Country Status (4)
Country | Link |
---|---|
US (2) | US20070214990A1 (en) |
AU (1) | AU2001292541A1 (en) |
CA (1) | CA2410465C (en) |
WO (1) | WO2001094277A2 (en) |
Cited By (2)
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FR2998566A1 (en) * | 2012-11-23 | 2014-05-30 | Nexter Munitions | PYROTECHNIC GAS GENERATING COMPONENT |
EP3029012A3 (en) * | 2014-12-06 | 2016-08-24 | TDW Gesellschaft für verteidigungstechnische Wirksysteme mbH | Device for the controlled initiation of the deflagration of an explosive charge |
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US9389055B2 (en) | 2010-04-15 | 2016-07-12 | Orica International Pte Ltd | High energy blasting |
US8393393B2 (en) | 2010-12-17 | 2013-03-12 | Halliburton Energy Services, Inc. | Coupler compliance tuning for mitigating shock produced by well perforating |
US8985200B2 (en) | 2010-12-17 | 2015-03-24 | Halliburton Energy Services, Inc. | Sensing shock during well perforating |
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US9297228B2 (en) | 2012-04-03 | 2016-03-29 | Halliburton Energy Services, Inc. | Shock attenuator for gun system |
WO2014046656A1 (en) | 2012-09-19 | 2014-03-27 | Halliburton Energy Services, Inc. | Perforation gun string energy propagation management system and methods |
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CN105218283B (en) * | 2015-08-25 | 2017-08-15 | 宜兴市阳生化工有限公司 | A kind of gluey emulsion of high explosion velocity type and preparation method thereof |
US10962311B2 (en) | 2019-01-16 | 2021-03-30 | Dos Viejos Amigos, LLC | Heat recovery steam generator cleaning system and method |
US11841198B2 (en) | 2019-01-16 | 2023-12-12 | Dos Viejos Amigos, LLC | Cleaning system and method |
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- 2001-05-23 AU AU2001292541A patent/AU2001292541A1/en not_active Abandoned
- 2001-05-23 WO PCT/US2001/016642 patent/WO2001094277A2/en active Application Filing
- 2001-05-23 CA CA002410465A patent/CA2410465C/en not_active Expired - Fee Related
-
2007
- 2007-01-11 US US11/622,252 patent/US20070214990A1/en not_active Abandoned
-
2009
- 2009-10-26 US US12/605,793 patent/US20100037793A1/en not_active Abandoned
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2998566A1 (en) * | 2012-11-23 | 2014-05-30 | Nexter Munitions | PYROTECHNIC GAS GENERATING COMPONENT |
WO2014080139A1 (en) * | 2012-11-23 | 2014-05-30 | Nexter Munitions | Pyrotechnic gas generator component |
US9574856B2 (en) | 2012-11-23 | 2017-02-21 | Nexter Munitions | Pyrotechnic gas generator component |
EP3029012A3 (en) * | 2014-12-06 | 2016-08-24 | TDW Gesellschaft für verteidigungstechnische Wirksysteme mbH | Device for the controlled initiation of the deflagration of an explosive charge |
US9829297B2 (en) | 2014-12-06 | 2017-11-28 | TDW Gesellschaft fuer verteidgungstechnische Wirksysteme mbH | Device for the controlled initiation of the deflagration of an explosive charge |
Also Published As
Publication number | Publication date |
---|---|
CA2410465C (en) | 2007-02-13 |
CA2410465A1 (en) | 2001-12-13 |
WO2001094277A3 (en) | 2002-04-11 |
US20100037793A1 (en) | 2010-02-18 |
US20070214990A1 (en) | 2007-09-20 |
AU2001292541A1 (en) | 2001-12-17 |
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