US3899374A - Calcium nitrate explosive composition - Google Patents

Calcium nitrate explosive composition Download PDF

Info

Publication number
US3899374A
US3899374A US456083A US45608374A US3899374A US 3899374 A US3899374 A US 3899374A US 456083 A US456083 A US 456083A US 45608374 A US45608374 A US 45608374A US 3899374 A US3899374 A US 3899374A
Authority
US
United States
Prior art keywords
percent
explosive composition
composition
mixture
water
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
Application number
US456083A
Other languages
English (en)
Inventor
Thomas E Sylkhouse
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dow Chemical Co
Original Assignee
Dow Chemical Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority to US456083A priority Critical patent/US3899374A/en
Application filed by Dow Chemical Co filed Critical Dow Chemical Co
Priority to BR4189/74A priority patent/BR7404189A/pt
Priority to SE7406873A priority patent/SE7406873L/
Priority to NL7406912A priority patent/NL7406912A/xx
Priority to ZA00743305A priority patent/ZA743305B/xx
Priority to FR7417958A priority patent/FR2272052A1/fr
Priority to DE19742424886 priority patent/DE2424886A1/de
Priority to JP49056783A priority patent/JPS50148514A/ja
Application granted granted Critical
Publication of US3899374A publication Critical patent/US3899374A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C06—EXPLOSIVES; MATCHES
    • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
    • C06B47/00—Compositions in which the components are separately stored until the moment of burning or explosion, e.g. "Sprengel"-type explosives; Suspensions of solid component in a normally non-explosive liquid phase, including a thickened aqueous phase
    • C06B47/14—Compositions in which the components are separately stored until the moment of burning or explosion, e.g. "Sprengel"-type explosives; Suspensions of solid component in a normally non-explosive liquid phase, including a thickened aqueous phase comprising a solid component and an aqueous phase

Definitions

  • An explosive composition is provided containing cal- 51 1111.
  • C1 C06b 19/00 eium nitrate as the predominate inorganic oxidizing 58 Field of Search 149/46, 60, 41, 2, 61, component, a Water miscible Organic fuel and Water- 23 Claims, 8 Drawing Figures PATENTED AUG 1 2W5 3, 899 374 SHEET 2 /00%Fue/ /00 NIL/41 N03 PATENTEU AUG 1 1975 SHEET /0o Fue/ /00 Formam/ae PATENTED AUG 1 2 I975 SHEET /00 7a E/hyleney/yco/ 2 ON 4 my N I00 N 4/VO CALCIUM NITRATE EXPLOSIVE COMPOSITION BACKGROUND OF THE INVENTION
  • Inorganic oxidizing salt based explosive compositions are well-known in the art.
  • compositions contain ammonium nitrate as the major inorganic oxidizing salt constituent.
  • Certain other inorganic oxidizing salts have been thought of as less potent or so sensitive and unstable as to be dangerous.
  • a portion of the ammonium nitrate has been replaced by other inorganic oxidizing salts such as, for example, sodium nitrate, calcium nitrate, certain perchlorates and other inorganic oxidizing salts.
  • These optional inorganic oxidizing salts have been employed for various purposes, such as economy, fluidizing properties, sensitivity enhancement and the like.
  • inorganic oxidizing salt based explosive compositions vary from dry to slurry mixtures containing water and/or other liquids, such as glycols, fuel oils and the like.
  • a typical dry mix known in the art is ANFO which contains ammonium nitrate and fuel oil.
  • Typical slurry explosive compositions contain inorganic oxidizing salts, normally a major portion comprising ammonium nitrate, water, a fuel and/or sensitizer and a thickening agent.
  • compositions which have a fudge point (i.e. salts begin to solidify and the composition thickens) which is above the borehole temperature so that the composition solidifies in the borehole or package.
  • a fudge point i.e. salts begin to solidify and the composition thickens
  • compositions are prepared at an elevated temperature (e.g. 70C [158F], col. 3, line 7 of 3,660,181 or at least 30C [86F], col. 3, line 35 of 3,713,917, preferably higher, i.e., 55C [131F], col. 5, line 17 of 3,713,917).
  • elevated temperature e.g. 70C [158F], col. 3, line 7 of 3,660,181 or at least 30C [86F], col. 3, line 35 of 3,713,917, preferably higher, i.e., 55C [131F], col. 5, line 17 of 3,713,917.
  • These systems are designed to firm up (i.e. have a fudge point of about 50C
  • compositions could be prepared at ambient temperatures, e.g. 75F, which were very mobile or even substantially completely fluid and which remain fluid down to temperatures as low as F or lower.
  • ambient temperatures e.g. 75F
  • sensitizers such as powdered metals, self explosives and the like, even though these constituents can be employed if desired.
  • the present invention concerns such compositions.
  • composition of the present invention comprises, as percent by weight at least about 50 percent of the following mixture: from about 51 to about 85 percent of a mixture of inorganic oxidizing salts consisting essentially of from about 53 to about 95 percent, of calcium nitrate, and the balance consisting essentially of ammonium nitrate; from about 9 to about 35 percent, of at least one water miscible organic fuel and from about 5 to about 21 percent H O, the balance, if any, of the composition comprising at least one additional fuel or sensitizer in addition to said water miscible organic fuel, density control agents, gelling or thickening agents and the like.
  • the amount of water of hydration, if any, associated with the calcium nitrate is included in the total amount of water present.
  • the calcium nitrate content is based on anhydrous calcium nitrate though other than anhydrous calcium nitrate can be employed to prepare the composition. Within the above described ranges it is desirable to adjust the individual constituents of the mixture so that the resulting mixture has an oxygen balance ranging from about +20 to about 8 grams of oxygen per 100 grams of total mix.
  • the weight ratio of the water miscible organic fuel to calcium nitrate should range from about 0.80 to about 0.20.
  • Sufficient gaseous voids should be provided in the composition to provide a bulk density therein ranging from about 0.80 to about 1.40 gm/cc.
  • Oxygen balance as employed herein means the amount of excess or paucity of oxygen (0 expressed as grams or grams of oxygen per 100 grams of total composition when combusted where the combustion products are taken to be CO H O, N and CaO. If a composition has a negative oxygen balance, there will be insufficient oxygen to combine with all of the hydro gen and carbon and H and CO will be formed upon detonation. If a composition has a positive oxygen balance nitrous oxide compounds will be formed.
  • FIG. 1 graphically illustrates certain data from Example 7.
  • FIG. 2 graphically illustrates certain data from Example 10.
  • FIGS. 3-5 graphically illustrate certain data from Example 11.
  • FIGS. 6-8 graphically illustrate certain data from Example l2.
  • the composition of the present invention comprises, as percent by weight, at least about percent of the following mixture: from about 55 to about of a mixture of inorganic oxidizing salts consisting essentially of from about 53 to about percent calcium nitrate, and the balance consisting essentially of ammonium nitrate; from about 10 to about 27 percent of a water miscible organic fuel selected from the group consisting of ethylene glycol, formamide, methanol, glycerol, diethylene glycol, or ethanol and mixtures thereof; and fromabout 7 to about 20 percent of water.
  • the mixture preferably has an oxygen balance ranging from about 0 to +15 grams for optimum sensitivity.
  • Formamide is especially preferred because of its beneficial effects on both the low temperature sensitivity and fluidity of the composition.
  • at least a portion (i.e. at least about 50% by weight) of the water miscible organic fuel comprises formamide.
  • a portion of water miscible organic fuel may comprise, in addition to formamide.
  • other fuels such as ethylene glycol, propylene glycol, methanol and the like.
  • the optimum weight ratio of the water miscible organic fuel to calcium nitrate will depend on the particular fuel employed. For example if the fuel is formamide. the weight ratio of formamide to calcium nitrate preferably ranges from 0.30 to about 0.70. If the fuel is ethylene glycol, the weight ratio of ethylene glycol to calcium nitrate should range from about 0.25 to about 0.70.
  • Water miscible organic fuels which can be employed in the composition comprise organic compounds and mixtures of compounds which are miscible in aqueous solutions of calcium nitrate.
  • groups of organic compounds which can be employed include certain amines, including primary, secondary, tertiary and quaternary amines; amides; alcohols including both monoand polyhydric alcohols; alcohol ethers; and low molecular weight carbohydrates (saccharides and polysaccharides).
  • Specific compounds which can be employed include, for example, formamide; glycerol; acetic acid, ethylene glycol monomethyl ether; methanol; ethanol; diethylene glycol; hexamethylene tetramine; hexamethylene tetramine monoand dinitrate; acetamide, ethylene glycol; propylene glycol; urea; thiourea; butylamine, metyl amine, ethylamine, thio diglycol; mono-, diand triethanol amines; and mixtures of compatible compounds.
  • Water soluble polymers may also be employed as additional fuels and in some instances also serve as thickening agents. Such polymers include, for example, polyamides, celluloses, galactomammans, e.g., guar, polyols, polyalkylamines, polyethyleneimines and other similar water miscible polymers.
  • the quantity of defined fuel in said mixtures is substantially completely mixable in the quantity of aqueous calcium nitrate solution present in said mixtures without separation of two liquid phases.
  • Organic fuels which are solid at room temperature will normally produce a thicker, less fluid blasting agent than those organic fuels which are fluid at about room temperature (e.g. 6874F).
  • an organic fuel is employed which when present in the indicated percent range is completely soluble in the aqueous oxidizer phase.
  • Inorganic oxidizing salts other than calcium nitrate and ammonium nitrate which can be employed in minor amounts include, for example, alkaline earth metal and alkali metal nitrates, sulfates, chlorates, and perchlorates, and specifically, sodium nitrate, ammonium perchlorate, barium nitrate, ammonium sulfate, sodium sulfate, sodium perchlorate, potassium perchlorate and the like. It has been found that certain of these inorganic oxidizing salts enhance certain explosive characteristics of the calcium nitrate mixture while others may hamper certain explosive characteristics but are advantageous for other reasons. For example, some salts may be employed to balance oxygen at the expense of some other feature such as sensitivity.
  • ammonium nitrate tends to increase the sensitivity of the calcium nitrate explosive to a certain degree.
  • Sodium nitrate tends to desensitize the calcium nitrate explosive when employed in amounts greater than about 30 percent by weight of the total composition but it may be employed to adjust the oxygen balance of the compositions.
  • additional inorganic oxidizing salts may be employed in particulate form, in solution or both.
  • Ammonium nitrate is preferred as the additional inorganic oxidizing salt because of its enhancing effect on sensitivity and fluidity within certain prescribed quantity limits.
  • Supplemental sensitizers and/or fuels in addition to those previously described can also be employed in the present composition to alter or improve certain explosive characteristics of the composition.
  • Those sensitizers and/or fuels normally employed in inorganic oxidizing salt based explosive compositions known in the art can be employed in the present invention.
  • These fuels and sensitizers comprise, for example, metals, selfexplosives and non-explosive water insoluble carbonaceous or other fuels such as sulfur and mixtures of two or more of these materials. They are employed in amounts sufficient to enhance the base explosive compositions in the manner desired.
  • metal may be employed in an amount to provide a weight ratio of metal to the base composition of up to l /1 and more.
  • the particle size distribution of the metal particles will effect certain characteristics of the blasting agent in a manner well known in the art.
  • Finer metal e.g. minus 200 mesh (US. Standard Sieve Series)
  • paint grade aluminum tends to sensitize the explosive composition to detonation, i.e. the composition can be initiated to detonation with a smaller less powerful initiator while coarser metal tends to increase the power of the composition when exploded, but with less sensitizing effect.
  • the sensitivity of the composition can be enhanced by adding from about 2 to about 10 percent by weight of paint grade aluminum to the mixture.
  • the use of such specific size metals are taught in US. Pat. Nos. 3,307,986 and 3,432,371, the teachings thereof being specifically incorporated herein by reference.
  • Particulate metals which can be employed include, for example, aluminum, magnesium, iron, silicon, titanium, aluminum alloys, magnesium alloys, ferrosilicon, silicon carbide, ferrophosphorous, zinc, boron and other like particulate metals which sensitize and/or function as a fuel in the explosive.
  • the light metals e.g. aluminum, magnesium, beryllium alloys thereof and the like.
  • the metals range in size from about 4 to about +325 mesh US Standard Sieve Series, although as shown in the examples -325 mesh metal can be employed to en hance certain characteristics of the composition.
  • certain inhibitors known in the explosives art may be employed to stabilize the compositions, e.g., certain phosphorous containing compounds and fatty acids.
  • Self-explosives refer to those nitrated organic substances which, by themselves, are generally recognized in the art as an explosive and which can usually be detonated with a standard blasting cap.
  • Examples of self-explosives which can be employed include organic nitrates, nitro compounds and nit'roamines, such as TNT, pentaerythritoltetranitrate (PETN), cyclotrimethylenetrinitramine (RDX), cyclotetramethylenetetranitramine (HMX), tetryl, nitrostarch, and explosive grade nitrocellulose as well as mixtures of the aforesaid and other self-explosives.
  • the self-explosives can be in any of the conventional forms such as flake, pelleted or cyrstalline. '7
  • water insoluble carbonaceous nonexplosive fuels and sensitizers include finely divided coal and carbon, solid carbonaceous vegetable products such as corn starch, wood pulp, ivory nut meal and bagasse, organic liquids such as hydrocarbon oils, fuel oils, fatty oils, vegetable oils, and mixtures of two or more of these water insoluble carbonaceous nonexplosive fuels.
  • These fuels may be blended into the water based mix with, for example, a suitable emulsifying agent to produce a water-in-oil or oil-in-water emulsion. They can also be used as a coating for nonsoluble fuels and other additives such as TNT, particulate metals and the like.
  • any grade of calcium nitrate e.g. anhydrous or hydrated may be employed in the present invention.
  • Anhydrous grade i.e. substantially free from water of hydration or absorbed water, or mono, di, tri, tetra or any other of the hydrated forms may be employed as well as water or organic liquid solutions of the hydrated calcium nitrate.
  • the water of hydration is considered in calculating the water content of the explosive.
  • the water present in the explosive may come from water of hydration, water may be added separately or a combination of the two can be employed.
  • Thickening and/or gelling agents can also be employed in the present compositions.
  • Gelling and/or thickening agents are employed which will swell and/or can be crosslinked in the liquid system containing dissolved Ca(NO;,) water, and the water soluble organic fuel.
  • suitable gelling agents include synthetic polymers, e.g., polyacrylamide, polyamines; starches; polysaccharides; flours e.g., wheat flour; galactomannan gums, such as guar, karaya and the like.
  • thickening agents which may be employed include polyalkylene glycol, hydroxyalkyl cellulose, potato starch, wheat starch, corn starch, carboxymethyl hydroxyethyl cellelose, methyl cellulose, polyethylene amine, carboxy methyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, and the like. It has been found that cellulosic materials, e.g. carboxymethyl hydroxyethyl cellulose, methyl and ethyl cellulose, and the like, and guar gums are preferred in the present invention.
  • thickeners which provide thickening and suspending characteristics by physical form include magnesium oxides, asbestos fibers, cotton fibers, glass fibers, wood fibers, and the like.
  • Suitable density control agents can also be employed in the present invention. These materials can be employed to decrease the density of the explosive, to sensitize the composition, to alter the energy release of the explosive composition and/or to provide composition which can be more readily exploded under elevated pressures and/or low temperatures.
  • Suitable density control agents include void-containing materials, for example, hollow spheres prepared from metals, clays, glass, thcrmoplastics, and thermosetting resins and other like materials. Specific examples of voidcontaining materials can be found in US. Pat. Nos. 3,456,589, 3,101,288 and 3,773,573, the teachings of these patents being specifically incorporated herein by reference.
  • void-containing materials such as ground corn cobs, bagasse, walnut shells and other like materials known in the art can be employed in the explosive.
  • the carbonaceous thickening, gelling and density control agents also provide additional fuel for the explosive composition.
  • void or gaseous generating chemicals may be employed to form gaseous voids in situ. Examples of such chemicals include certain nitrites alone or in combination with sulfamic acid, certain sulfamates, carbonates and bicarbonates. Other such void generating compounds include, for example, combinations of carbonates or bicarbonates and acids, e.g. HCl and the like.
  • gaseous bubbles may be incorporated into the mix during its manufacture, such as by whipping air into the mix which are stabilized with viscosity building polymers and the like.
  • compositions of the present invention range from watery clear fluid substances to very thick masses containing particulates, e.g. particulate inorganic oxidizing salts and/or sensitizers, and/or fuels.
  • the explosive compositions of the present invention may be prepared in the following manner.
  • the requisite amount of water soluble organic fuel and water are mixed together. Any density control agents which may be employed are then added to this mixture.
  • Particulate materials e.g. calcium nitrate, inorganic oxidizing salts, metals, etc. are then blended into the liquid mixtures and stirred until a uniform mixture is formed.
  • the thickening agent preferably dispersed in a dispersing agent, e.g. particulate salts or a water soluble liquid in which the polymer does not swell or swells very slowly, e.g. propylene glycol, is then blended in and the composition stirred until the viscosity becomes sufficient to hold the particulate constituents in suspension.
  • compositions are unique in that they are more sensitive to detonation at low temperatures, maintain better fluidity at low temperatures, and can be detonated at higher densities at low temperatures than similar explosives which contain ammonium nitrate as the major inorganic oxidizing salt or calcium nitrate in lesser amounts.
  • a thin walled cylindrical polyethylene container about 1- /8 inches in diameter and having a volume capacity of about l67 cc was filled with a test composition having a known density and temperature.
  • the filled container was centered on a cylindrical steel driving plate about 4 inches in diameter and inch thick (except as otherwise noted herein).
  • the driving plate in turn was centered on the top of a 1- /2 inch diameter by 3 inch long cylindrical cast lead block.
  • the lead book was placed on top of a 6 inch diameter by 1- /2 inch thick cylindrical steel base plate which was placed on the ground.
  • a detonator and high explosive booster charge was placed on top of the polyethylene container and the test composition detonated. The decrease in the height of the lead block was then measured.
  • compositions (Table I) were prepared containing in different proportions either formamide, ethylene glycol, or 50/50 weight ratio formamide/ethylene glycol mixture as the water soluble organic fuel, ammonium nitrate, fertilizer grade calcium nitrate and water. Each of these compositions was tested in the standard lead block detonation test, as previously defined, employing a 37 gram 50/50 pentolite booster (a cast mixture of equal parts of pentaerythritol tetranitrate and trinitrotoluene) and a N0. 6 blasting cap as a detonator. The densities of the compositions were controlled by the addition of plastic microballoons which had a bulk density of about 0.03 gm/cc.
  • the samples to be tested were prepared by blending the water, fuel, plastic balloons and ground NH NO and Ca(NO with stirring for from 6 to 8 hours.
  • the plastic balloons were added in an amount to provide the density desired in each test.
  • About 1.5 parts by weight (per 100 parts of total mix) of carboxymethyl hydroxyethyl cellulose gelling agent was blended with about 3 parts by weight of propylene glycol and this blended into the slurry.
  • the thickening agent and propylene glycol which were added are characteristic of water soluble organic fuels which can be employed in the present invention. The amount of such additional fuel was taken into consideration when determining the scope of the present invention as defined herein.
  • the compositions were allowed to thicken to a rubbery consistency and then placed in the lead block containers.
  • Tables 11 V11 show the results of the lead block tests in Series l-6 as defined above.
  • AH represents the deformation (inches of the lead block for each shot.
  • X represents the lead block deformation divided by the density of the composition tested. This factor allows for the comparison of AH valves where the compositions being compared did not have equal densities, since for fully propagating explosives the deformation for like volumes of explosive is proportional to the densities of the explosives.
  • the 0.5 inch deforma- 2 ,2 g tion was an arbitrarily chosen cut off point based on 8 g 39 34 previous observations that when a composition failed g 1 to give such a deformation it also usually failed at a 11 27 9 64 lower temperature.
  • Six series of tests were run; employ- 3O 12 27 O 73 13 19 58 23 mg 26 different base composltions.
  • the Ser1es differed 14 19 4g 33 from each other first, in that in Series 1, 2 and 3 formg; g; amide was employed as the fuel and in Series 4, 5 and 17 19 18 63 6 ethylene glycol was employed as the fuel.
  • 18 19 8 73 Series 2, and 3, 5 and 6 differed from Series 1 and 4 1?
  • AN mmnunium nitrate "SN sodium nitrate”
  • F l'tnmnmidu 'F.(i ethylene glycol PG promlene glycol one-third pound high density booster charge.
  • the pail EXAMPLE 3 was sealed with a lid through which the detonating cord extended. Water resistance was assured by a gasket As a further example of the superior low temperature sealing assembly at the opening where the detonating sensitivity of compositions falling within the scope of cord came through the lid.
  • the detonatthe present invention several compositions were preing cord was connected to an initiator and firing line pared containing CNF, formamide, water and ammoand the pail was suspended in a body of water at about nium nitrate.
  • compositions were prepared conhalf the depth of a lake (pail placed at about 42.5 feet taining the constituents as parts by weight as set forth beneath the surface ofthe water).
  • the composition was in the following Table lX.
  • the compositions were exploded and the resulting pressure profile from the extested in the previously defined standard lead block test plosion was converted into electrical impulses by a piat 45F, the primer consisting of a 37 gram 50/50 penezoelectric gauge suspended in the water at the same tolite booster.
  • the results of the tests are also tabulated level a known horizontal distance from the explosive. in the Table IX.
  • Each composition varied from compo- The electrical impulses were recorded and converted sition of test No.
  • H1 H1 88 0.79 maintaining the ratio of CNF to formamide approxi- NH NO 1.00 0.89 0.82 NI-LNQ, 42.11 1.07 0.90 0.84 mately the same.
  • the coompositlons were tested at a NHNO 667 L04 0485 0.82 temperature of about 70 F in the prevlously defined 101-1 100. 0 107 0x5 0 standard lead block test and AH and X. as defined here- 7 S1 E3 T I inbefore. tabulated for each.
  • the base compositions L I Mates A-D. as parts by weight, the additives (parts Qi 218 1 15 0.15 0.13
  • EXAMPLE 6 TABLE XV
  • different water soluble organic fuels were employed while keeping the weight ratio of CNF. 35 of different water soluble organic fuels and mixtures of fuel, water and ammonium nitrate approximately equal.
  • the compositions were tested in the aforemen- Composition No. Parts by Wt.
  • EXAMPLE 7 Several compositions containing the constituents listed below were tested in the aforementioned lead block test at a temperature of about 70F in the manner as defined in the previous examples. Metal was added to some of these compositions and also different water soluble organic fuels were employed. The compositions are listed in the following Table XVII as percent by weight:
  • Ca(NO 4H O was employed and the amount of water in the composition takes into account the 4 wa-.
  • composition B there was substantial deformation of the lead block even at a density of about 1.5 gm/cc.
  • composition No. l falls within the scope of the pres ent invention while compositions 2-4 consist of formulations of commercially available explosives.
  • the tests consisted of l) a plate dent test to determine average detonation velocity of a confined explosive and dent pressure; (2) a detonation velocity test of unconfined explosive and (3) a cone test to determine minimum critical diameter.
  • the average detonation velocity of a confined explosive is determined. Both the detonation velocity and the plate dent relate to the peak pressure or brisanee of the explosive.
  • a 2 inch inside diameter extra heavy open ended steel pipe inches long was filled with an explosive composition to be tested.
  • the pipe contained two ports through the wall thereof a known distance apart. Contactors were inserted through these ports and were employed to determine the velocity of detonation.
  • One end of the pipe was centered on a cylindrical steel plate 3 inches in diameter and 4 inches thick.
  • a 37 gram high pressure primer was centered on the opposite end of the pipe in contact with the explosive mixture. The primer was detonated with an electric blasting cap.
  • the detonation velocity was determined upon detonation by suitable timing instrumentation known to those skilled in the art which measured the time for the detonation wave to progress from the first to second contactors.
  • the plate dent pressure is determined from calculations known in the art based upon the dent produced by the explosive in the steel base plate.
  • the unconfined detonation velocity test was determined by placing an explosive to be tested in a cardboard tube 16 inches long and of constant diameter over the length thereof. The diameter is any diameter which is greater than the critical diameter of the explosive being tested. The velocity was measured by employing contactors in the same manner as described for the plate dent test. A 37 gram high pressure booster was placed at one end of the tube in contact with the explosive and the booster armed and detonated with an electric blasting cap.
  • the third test consisted of a cone test to determine the minimum diameter column of explosive which will sustain propagation.
  • cone test hollow tapered tubes constructed of cardboard 24 inches long were filled with the explosive to be tested.
  • the explosives to be tested were first tested in a tube which evenly tapered from 4 to 3 inches in diameter. If the entire col umn of explosive propagated a like composition was then placed in a tube which tapered evenly from 3 inches to 2 inches in diameter. The explosive was always detonated from the larger end of the tube. After the detonation the diameter of any remains of the tube were measured at the position where the explosive appeared to fail to propagate.
  • EXAMPLE 9 Explosive compositions were prepared from base mixes comprising; Mix A, 30 percent formamide and percent CNF; and Mix B, 28 percent formamide. 57 percent CNF and 15 percent NH NO Plastic balloons were employed as a density control agent and carboxy methyl hydroxyethyl cellulose was employed as a thickener. Additional NH NO and particulate aluminum were premixed into some of these base mixes and they were tested in small diameter cardboard and metal tubes. The results, diameters, size of initiator and formulations are set forth in the following Table XXI.
  • compositions were shot at about 70F.
  • the boosters consisted of 50/50 pentolite in an amount as shown or a blasting cap.
  • an indication of the fluidity of a composition was determined by observing the proportion of a mixture occupied by undissolved solids when the system had reached equilibrium. This parameter was chosen since the fluidity (and pumpability) of slurry explosives decreases as volume occupied by the solids approaches the volume occupied by the total composition.
  • EXAMPLE 10 25 samples were stirred by hand 2 or 3 times daily for several days and then allowed to settle. They were not placed on mechanical stirrers due to possible evaporation loss. The methanol system was observed both at room (75F) and 6F temperatures.
  • the t Settle Overnight Thfi height of Solid y r 1 and points represent the composition tested and the numthe total miXtul'e height 1 in the tain r fi bers over the points represent the R value (for that measured n the T8110 Obtained 2181 40 composition).
  • These lines of approximately constant R values were obtained by visual interpolation. They demonstrate that better fluidity properties are obtained H at higher Ca(l ⁇ 1O levels at even less liquid content 100 Ht) than at the higher NH NO levels.
  • the data obtained on 45 the other fuel systems when plotted in this manner Data were obtained in this way for mixtures of fertilshow similar fluidity characteristics.
  • FIG. 7 the dots represent the percent by weight of the 3 constituents in each test composition and in all the figures the solid curves represent approximately constant R values of about 25 percent.
  • FIG. 7 gives the change in solubility noted for the system containing no water except that originally in the CNF.
  • FIG. 8 is similar data for the system containing 10% added H 0.
  • FIG. 9 is a composite of 10F data showing the curves for 0. 5 and 10% added water.
  • EXAMPLE I2 Eleven different base compositions plus 10 percent by weight additional water were formulated for each of 3 fuels, formamide, ethylene glycol and methanol. and placed into 2 quart (stacked 1 quart cylindrical cardboard containers about 3 inches in diameter) and cooled to 20F. These samples were tested for fluidity by observing the relative ease with which one finger could be inserted into the mix with normal hand pressure.
  • Plasticity was reported as H if the mix was so hard that it could not be deformed appreciably with finger pressure. It was rated P if it was deformable plastic, similar to a very heavy grease or soft wax. An S rating indicates that the mix was very soft and required little or no force to deform it.
  • FIGS. 10 to 12 show the plasticity data obtained in this manner for the different compositions tested at 20F.
  • the letter corresponding to the plasticity is positioned on the diagram at the point corresponding to its fuel. NH NO CNF composition ratio.
  • EXAMPLE 13 Certain compositions coming within the scope of the present invention were prepared containing the constituents set forth in the following Table XXIV. The minimum initiator required to detonate a 2 inch diameter column of the composition at 35F was determined. Also the detonation velocity of each composition was determined by the Dautriche method. The compositions and results of these tests are set forth in the following Table XXIV.
  • composition 4. plastic explnshc containing -90"; RDX and 10; inert hinder.
  • An explosive composition which comprises. at least about 50 percent. as percent by weight. of the following mixture:
  • inorganic oxidizing salts consisting essentially of ammonium nitrate and calcium nitrate wherein calcium nitrate consists of from about 53 to about 95 percent of said inorganic oxidizing salts;
  • said composition having an oxygen balance ranging from about +20 grams to about 8 grams of oxygen per 100 grams of said mixture.
  • said weight ratio of said water miscible organic fuel to calcium nitrate in said mixture ranging from about 0.80 to about 0.20 and sufficient gaseous voids incorporated in said mixture to provide a bulk density ranging from about 0.80 to 1.40 gm/cc.
  • the explosive composition of claim 1 including in addition up to about 50 percent of at least one sensitizer or fuel in addition to said water miscible organic fuel wherein each of components (a), (b) and (c) is proportionately decreased by the amount of said second sensitizer or fuel.
  • the explosive composition of claim 1 including in addition particulate aluminum.
  • the explosive composition of claim 1 including in addition particulate magnesium.
  • the explosive composition of claim 1 including in addition paint grade aluminum.
  • the explosive composition of claim 1 including in addition small void containing plastic spheres as a density control agent.
  • water miscible organic fuel is at least one of ethylene glycol, formamide. propylene glycol. methanol, ethanol. glycerol or diethylene glycol.
  • the explosive composition as defined in claim 1 including in addition at least one of a gelling or thickening agent.
  • the explosive composition as defined in claim 1 including in addition a cellulosic thickening agent.
  • An explosive composition which comprises at least about percent by weight of the following mixture:
  • inorganic oxidizing salts consisting essentially of calcium nitrate and ammonium nitrate wherein said calcium nitrate ranges in amount from about 53 to about percent of said inorganic oxidizing salts;
  • At least one water miscible organic fuel selected from the group consisting of formamide. ethylene glycol, methanol. ethanol, glycerol. diethylene glycol or propylene glycol;
  • said component (a) ranging from about 55 to about 75 percent of the total of components (a), (b) and (c), said component (b) ranges from about 10 to about 27 percent by weight of the total components (a), (b) and (c) and said component (0) ranges from about 7 to about 20 percent by weight of the total of components (a), (bl and (c).
  • said mixture has an oxygen balance ranging from about +20 to about 8 grams of oxygen per grams of mixture, and the weight ratio of said water miscible organic fuel to calcium nitrate ranges from about 0.20 to about 0.80;
  • the explosive composition of claim 14 including in addition paint grade aluminum in an amount ranging from about 2 to about 10 percent.
  • the explosive composition of claim 14 including sufficient water and water miscible organic fuel to dissolve substantially all the inorganic oxidizing salts at room temperature.
  • An explosive composition which comprises:
  • inorganic oxidizing salts consisting essentially of from about 15 to about 47 percent ammonium nitrate and from about 53 to about 85 percent calcium nitrate;
  • composition having an oxygen balance ranging from about +20 to about 8 grams of oxygen per grams of mixture and having a weight ratio of organic fuel to calcium nitrate ranging from about 0.30 to about 0.70.
  • the explosive composition of claim 20 including in addition a thickening or gelling agent.
  • the explosive composition of claim 20 containing in addition sufficient gaseous voids to provide a bulk density in said mixture ranging from about 0.80 to about 1.4 gm/cc.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Solid Fuels And Fuel-Associated Substances (AREA)
  • Liquid Carbonaceous Fuels (AREA)
US456083A 1974-03-29 1974-03-29 Calcium nitrate explosive composition Expired - Lifetime US3899374A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
US456083A US3899374A (en) 1974-03-29 1974-03-29 Calcium nitrate explosive composition
SE7406873A SE7406873L (sv) 1974-03-29 1974-05-22 Kalciumnitrathaltigt sprengemne.
NL7406912A NL7406912A (nl) 1974-03-29 1974-05-22 Explosief mengsel op basis van anorganische oxyderende zouten, alsmede werkwijze voor het bereiden daarvan.
ZA00743305A ZA743305B (en) 1974-03-29 1974-05-22 Calcium nitrate explosive composition
BR4189/74A BR7404189A (pt) 1974-03-29 1974-05-22 Composicao explosiva e processo para sua preparacao
FR7417958A FR2272052A1 (enrdf_load_stackoverflow) 1974-03-29 1974-05-22
DE19742424886 DE2424886A1 (de) 1974-03-29 1974-05-22 Explosive calciumnitrat-komposition
JP49056783A JPS50148514A (enrdf_load_stackoverflow) 1974-03-29 1974-05-22

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
US456083A US3899374A (en) 1974-03-29 1974-03-29 Calcium nitrate explosive composition
SE7406873A SE7406873L (sv) 1974-03-29 1974-05-22 Kalciumnitrathaltigt sprengemne.
NL7406912A NL7406912A (nl) 1974-03-29 1974-05-22 Explosief mengsel op basis van anorganische oxyderende zouten, alsmede werkwijze voor het bereiden daarvan.
ZA00743305A ZA743305B (en) 1974-03-29 1974-05-22 Calcium nitrate explosive composition
BR4189/74A BR7404189A (pt) 1974-03-29 1974-05-22 Composicao explosiva e processo para sua preparacao
FR7417958A FR2272052A1 (enrdf_load_stackoverflow) 1974-03-29 1974-05-22
DE19742424886 DE2424886A1 (de) 1974-03-29 1974-05-22 Explosive calciumnitrat-komposition
JP49056783A JPS50148514A (enrdf_load_stackoverflow) 1974-03-29 1974-05-22

Publications (1)

Publication Number Publication Date
US3899374A true US3899374A (en) 1975-08-12

Family

ID=27570190

Family Applications (1)

Application Number Title Priority Date Filing Date
US456083A Expired - Lifetime US3899374A (en) 1974-03-29 1974-03-29 Calcium nitrate explosive composition

Country Status (8)

Country Link
US (1) US3899374A (enrdf_load_stackoverflow)
JP (1) JPS50148514A (enrdf_load_stackoverflow)
BR (1) BR7404189A (enrdf_load_stackoverflow)
DE (1) DE2424886A1 (enrdf_load_stackoverflow)
FR (1) FR2272052A1 (enrdf_load_stackoverflow)
NL (1) NL7406912A (enrdf_load_stackoverflow)
SE (1) SE7406873L (enrdf_load_stackoverflow)
ZA (1) ZA743305B (enrdf_load_stackoverflow)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4091213A (en) * 1975-12-12 1978-05-23 Bristol-Myers Company 7-Cyclizedamino-3-heterothiomethyl cephalosporin derivatives
FR2490213A1 (fr) * 1980-09-12 1982-03-19 Ireco Chemicals Composition explosive antigrisouteuse contenant du nitrate de calcium
US4416711A (en) * 1982-12-17 1983-11-22 Ireco Chemicals Perchlorate slurry explosive
US4439254A (en) * 1982-04-05 1984-03-27 Atlas Powder Company Solid sensitizers in water gel explosives and method
US4453989A (en) * 1982-04-05 1984-06-12 Atlas Powder Company Solid sensitizers for water-in-oil emulsion explosives
US4547234A (en) * 1983-07-15 1985-10-15 Nippon Oil And Fats Company Limited Explosive composition
US4693765A (en) * 1986-05-22 1987-09-15 Stromquist Donald M Gel type slurry explosive and matrix and method for making same
US4701227A (en) * 1987-02-05 1987-10-20 Loverro Jr Nicholas P Ammonium nitrate explosive compositions
US4978400A (en) * 1989-11-17 1990-12-18 General Sciences, Inc. Synergistic composite pyrotechnic material
US4980000A (en) * 1990-01-17 1990-12-25 Atlas Powder Company Nitrostarch emulsion explosives production process
US5007973A (en) * 1989-10-12 1991-04-16 Atlas Powder Company Multicomponent explosives
US5051142A (en) * 1990-01-17 1991-09-24 Atlas Powder Company Emulsion explosive containing nitrostarch
US5089652A (en) * 1990-01-17 1992-02-18 Atlas Powder Company Nitrate ester preparation
US6238500B1 (en) * 1999-07-26 2001-05-29 Trw Inc. Smokeless gas generating material
US6334917B1 (en) * 1998-10-23 2002-01-01 Autoliv Asp, Inc. Propellant compositions for gas generating apparatus
US20080245450A1 (en) * 2007-01-23 2008-10-09 Bioenergy Systems, Llc Explosive Compositions Containing Glycerin
US8101032B1 (en) * 2007-05-18 2012-01-24 University Of Central Florida Research Foundation, Inc. Ethanol based gel fuel for a hybrid rocket engine
US11774224B1 (en) * 2022-03-08 2023-10-03 Wuhan University Of Technology Device and method for evaluating damage power of internal explosion
RU2805088C2 (ru) * 2019-08-01 2023-10-11 Михаил Николаевич Оверченко Эмульсионный взрывчатый состав

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4356044A (en) * 1981-03-23 1982-10-26 Ireco Chemicals Emulsion explosives containing high concentrations of calcium nitrate

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3660181A (en) * 1969-05-01 1972-05-02 Intermountain Res & Eng Blasting slurry compositions containing calcium nitrate and method of preparation
US3713917A (en) * 1970-11-16 1973-01-30 Ireco Chemicals Blasting slurry compositions contain-ing calcium nitrate and method of preparation
US3787254A (en) * 1971-06-01 1974-01-22 Ireco Chemicals Explosive compositions containing calcium nitrate
US3816191A (en) * 1970-05-04 1974-06-11 Dow Chemical Co Method of making calcium nitrate explosive composition

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3660181A (en) * 1969-05-01 1972-05-02 Intermountain Res & Eng Blasting slurry compositions containing calcium nitrate and method of preparation
US3816191A (en) * 1970-05-04 1974-06-11 Dow Chemical Co Method of making calcium nitrate explosive composition
US3713917A (en) * 1970-11-16 1973-01-30 Ireco Chemicals Blasting slurry compositions contain-ing calcium nitrate and method of preparation
US3787254A (en) * 1971-06-01 1974-01-22 Ireco Chemicals Explosive compositions containing calcium nitrate

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4091213A (en) * 1975-12-12 1978-05-23 Bristol-Myers Company 7-Cyclizedamino-3-heterothiomethyl cephalosporin derivatives
FR2490213A1 (fr) * 1980-09-12 1982-03-19 Ireco Chemicals Composition explosive antigrisouteuse contenant du nitrate de calcium
US4439254A (en) * 1982-04-05 1984-03-27 Atlas Powder Company Solid sensitizers in water gel explosives and method
US4453989A (en) * 1982-04-05 1984-06-12 Atlas Powder Company Solid sensitizers for water-in-oil emulsion explosives
US4416711A (en) * 1982-12-17 1983-11-22 Ireco Chemicals Perchlorate slurry explosive
US4547234A (en) * 1983-07-15 1985-10-15 Nippon Oil And Fats Company Limited Explosive composition
US4693765A (en) * 1986-05-22 1987-09-15 Stromquist Donald M Gel type slurry explosive and matrix and method for making same
US4701227A (en) * 1987-02-05 1987-10-20 Loverro Jr Nicholas P Ammonium nitrate explosive compositions
US5007973A (en) * 1989-10-12 1991-04-16 Atlas Powder Company Multicomponent explosives
US4978400A (en) * 1989-11-17 1990-12-18 General Sciences, Inc. Synergistic composite pyrotechnic material
US4980000A (en) * 1990-01-17 1990-12-25 Atlas Powder Company Nitrostarch emulsion explosives production process
US5051142A (en) * 1990-01-17 1991-09-24 Atlas Powder Company Emulsion explosive containing nitrostarch
US5089652A (en) * 1990-01-17 1992-02-18 Atlas Powder Company Nitrate ester preparation
US6334917B1 (en) * 1998-10-23 2002-01-01 Autoliv Asp, Inc. Propellant compositions for gas generating apparatus
US6238500B1 (en) * 1999-07-26 2001-05-29 Trw Inc. Smokeless gas generating material
US20080245450A1 (en) * 2007-01-23 2008-10-09 Bioenergy Systems, Llc Explosive Compositions Containing Glycerin
WO2008091795A3 (en) * 2007-01-23 2009-04-16 Bioenergy Systems Man Llc Explosive compositions containing glycerin
US8101032B1 (en) * 2007-05-18 2012-01-24 University Of Central Florida Research Foundation, Inc. Ethanol based gel fuel for a hybrid rocket engine
RU2805088C2 (ru) * 2019-08-01 2023-10-11 Михаил Николаевич Оверченко Эмульсионный взрывчатый состав
US11774224B1 (en) * 2022-03-08 2023-10-03 Wuhan University Of Technology Device and method for evaluating damage power of internal explosion

Also Published As

Publication number Publication date
SE7406873L (sv) 1975-11-24
NL7406912A (nl) 1975-11-25
JPS50148514A (enrdf_load_stackoverflow) 1975-11-28
FR2272052A1 (enrdf_load_stackoverflow) 1975-12-19
BR7404189A (pt) 1976-02-03
ZA743305B (en) 1975-06-25
DE2424886A1 (de) 1975-12-04

Similar Documents

Publication Publication Date Title
US3899374A (en) Calcium nitrate explosive composition
US3765967A (en) Liquid and slurry explosives of controlled high sensitivity
US20080245450A1 (en) Explosive Compositions Containing Glycerin
US3190777A (en) Fluidizing agents for water-bearing explosive compositions
US3238074A (en) Extrudable explosive composition of semi-solid or thixotropic consistency containing flake aluminum
US3395056A (en) Inorganic oxidizer salt-alcohol explosive slurry containing an alcohol thickening agent
US3153606A (en) Aqueous explosive composition containing flake aluminum and ammonium nitrate
US3839107A (en) Calcium nitrate explosive composition
US3431155A (en) Water-bearing explosive containing nitrogen-base salt and method of preparing same
US4718954A (en) Explosive compositions
US3816191A (en) Method of making calcium nitrate explosive composition
US4474628A (en) Slurry explosive with high strength hollow spheres
US4547232A (en) Sensitization of water-in-oil emulsion explosives
US3083127A (en) Aqueous nitrostarch explosive slurries
US4032375A (en) Blasting composition containing calcium nitrate and sulfur
US3356544A (en) Inorganic oxidizer salt aqueous blasting compositions containing a nitroparaffin
Sudweeks Physical and chemical properties of industrial slurry explosives
US4555276A (en) High density pressure resistant invert blasting emulsions
US3734864A (en) Aqueous gel for slurry explosives composition and method of preparing said gel
US6214140B1 (en) Development of new high energy blasting products using demilitarized ammonium picrate
US3147163A (en) Sensitized oil-slurried explosives
US3728173A (en) Dense explosive slurry compositions of high energy containing a gum mixture
US3432371A (en) Dry explosive composition containing particulate metal of specific mesh and gauge
US3695948A (en) Cast explosive composition containing thiourea
US3390030A (en) Aqueous slurry blasting composition of non-explosive ingredients containing silicon ad an aeration agent