JP2769544B2 - Explosive stability test equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for testing the stability of nitrate ester explosives used in propellants and rocket propellants.

[0002]

2. Description of the Related Art Conventionally, techniques in such a field include:
For example, there is one disclosed in the following literature. (1) Junichi Kimura Journal of the Pharmaceutical Society of Japan “EXPLOSIO
N "Vol. 4, No. 2, 1994, p. 63-6
9 (2) Junichi Kimura Defense Technology July 1992 p.
16 (3) Masao Tanaka, Shoji Koma, Phthalocyanine (Bunshin Publishing) p. 68-p. 76 (4) JP-A-7-112767 Explosives have an unstable chemical bond (C—N, O—
(N, NN) can be regarded as a self-heating substance. Therefore, spontaneous decomposition occurs without the presence of air even at around normal temperature, generating decomposition gas and heat, sometimes leading to ignition, which may cause a great disaster.

[0003] As an example of an actual disaster, nitrocellulose stored in a drum in a warehouse in Shinagawa, Tokyo in the summer of 1964 in a wet state dries in a hot summer and causes spontaneous ignition.
In some cases, this fire triggered a massive explosion of organic peroxide, resulting in numerous casualties. The problem of spontaneous decomposition in the storage temperature range is a nitrate ester having a weak ON bond and explosives containing this as a main component. Recently, the use of nitrates in the field of industrial explosives has declined due to a significant drop in dynamite production, but in the field of military explosives, almost all propellants and smokeless rocket propellants are still the main players. The component is a nitrate ester. For military personnel, it is necessary to estimate the useful life of stockpiled ammunition and to establish robust disposal standards to ensure safety.

[0004] As a method for testing the stability of nitrate ester explosives, as described in the above-mentioned references (1) and (2), nitrogen oxides generated by decomposition from explosives have been long. The measurement of NOx has been performed by a surveillance test or an Abel test. In the surveillance test, 45 g of a sample was taken in a transparent wide-mouthed bottle (about 50 mm in inner diameter, 140 mm in height).
Store it in a heating tank kept at 5.5 ° C and observe it visually until the concentration of generated NO ₂ red smoke becomes equivalent to that of NO ₂ enclosed in an ampoule. And is being implemented at military ammunition-related facilities.

In the Abel test, a standard color (light purple) is formed at the boundary between wetness and dryness at the center of potassium iodide starch test paper due to NOx generated from a sample heated to 65.5 ° C.
Is visually measured to determine whether or not it can be used based on the required time.

[0006]

However, the surveillance test requires a period of several months to several years to obtain a judgment result, and the judgment is performed visually, so that the judgment involves ambiguity. there were. On the other hand, in the Abel test, the determination can be performed in a few minutes, but in this test, the determination is performed visually, and thus, there is a problem that the determination is also accompanied by ambiguity.

In order to solve the problems described in the above-mentioned references (1) and (2) and to speed up and standardize the stability test method for nitrate ester explosives, recently, a surveillance test and an abel test have been conducted. Attempts have been made to replace with a simple NOx meter using a semiconductor photodetector, a quantitative analysis of stabilizers by various chromatographs, a calorific value measuring method using a microcalorimeter, a chemiluminescent method using an ultra-low light measuring device, and the like.

However, according to these methods, there is a problem that the apparatus is expensive and the measurement procedure is complicated, and it has not yet been put to practical use. On the other hand, the present inventors have noticed that various gases are well adsorbed on the phthalocyanine thin film as shown in the above-mentioned document (3). Then, as shown in the above-mentioned reference (4), NOx generated due to decomposition of explosive is detected by using a gas sensor element having a phthalocyanine-sensitive film as a sensitive film, so that it is easy, quick and human. A method for testing the stability of non-subjective standardized nitrate explosives is provided.

According to the present invention, the above-mentioned test method is further used.
Easy and quick, standardized without human subjectivity,
An object of the present invention is to provide a suitable explosive stability testing device.

[0010]

According to the present invention, there is provided a gas explosive stability test apparatus, comprising: a first container in which an explosive sample is sealed; and a gas sensor having a phthalocyanine as a sensitive film. , A constant temperature bath for heating the first container, tubes for introducing and flowing a carrier gas into the first container and the second container, and a device for measuring a change in characteristics of the gas sensor Are provided.

(2) In the explosive stability testing apparatus, a gas sensor having a phthalocyanine-sensitive film is disposed, a container for sealing the explosive sample, a thermostat for heating the container, and a carrier in the container. A tube for introducing and flowing gas and a device for measuring a change in characteristics of the gas sensor are provided. (3) In the explosive stability test apparatus according to the above (2), the container is partitioned into a first portion in which the explosive sample is sealed and a second portion in which the gas sensor is installed, and the carrier gas is supplied to the three-way cock. Through the first part to the second part or flow out of the container.

(4) In the explosive stability testing apparatus according to the above (1) or (2), the gas sensor measures a change in electrical characteristics of the sensitive film due to gas adsorption to the phthalocyanine sensitive film by a pair of electrodes. It is like that. (5) In the explosive stability testing apparatus according to (4), the electrode is a comb-shaped electrode.

(6) In the explosive stability testing apparatus according to the above (1) or (2), the tubes are a Teflon tube, a viton tube, or a silicon tube.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic view of an explosive stability test apparatus showing an embodiment of the present invention, FIG. 2 is a plan view of a gas sensor of the explosive stability test apparatus, and FIG. 3 is a second container of the explosive stability test apparatus. FIG.

In this embodiment, as shown in FIG. 2, as a gas sensor 10, a gold thin film electrode is deposited on a glass substrate 11 having a size of 10 × 15 mm and a thickness of 1 mm. The distance between the electrodes is 50 μm. A sensor element having a copper phthalocyanine sensitive film 14 in which copper phthalocyanine (manufactured by Toyo Ink Co., Ltd.) is vacuum-deposited on a substrate having a comb-shaped electrode 13 having a width of 50 μm is used as an instrument for measuring a change in electric resistance of the sensor element. And an insulation resistance meter (manufactured by Yokogawa Hewlett-Packard Company: 4329A). Reference numeral 12 denotes a connection terminal of the comb-shaped electrode.

A 500 ml screw-cap glass bottle was used as the first container 20 for sealing the explosive sample, and a constant temperature water tank 23 was used to heat the glass bottle. Second container 25 in which gas sensor 10 having phthalocyanines as a sensitive film is installed.
As shown schematically in FIG. 3, a stainless steel container was used. In FIG. 3, reference numeral 25a denotes a gas inlet, 25b denotes a gas outlet, and 26a denotes a lead wire connected to the insulation resistance meter 26.

A tube 24 for introducing a carrier gas is provided between the first container 20 and the second container 25. As the tube 24, a Teflon tube was used. Further, a recorder 27 capable of recording a change in the electric resistance is connected to the insulation resistance meter 26. Further, NOx gas generated from the second container 25 is commercially available NO ₂ -NO converter 28A and NO using the chemiluminescence method simultaneously
It is introduced into a NOx meter 28 composed of an x detector 28B, and its concentration is measured.

Hereinafter, the operation of the explosive stability testing apparatus will be described. First, the first container 20 is filled with an appropriate amount of glass beads 22, and 6 g of the double base powder (2 g
1) was wrapped and placed in a nylon mesh, immersed in a constant temperature water bath 23, and heated at 65 ° C. Next, the first container 20
Dry air (dry ai) as carrier gas
r) was introduced at a flow rate of 1 L / min, allowed to flow, and allowed to stand for 30 minutes (the gas flowed at this time was not introduced into the second container 25). After a lapse of 30 minutes, the gas containing NOx generated from the explosive was introduced into the second container 25 in which the above-described gas sensor 10 was installed, and the electric resistance change of the gas sensor 10 was measured by the insulation resistance meter 26. In addition, this gas was used simultaneously with a commercially available NOx meter using a chemiluminescence method (manufactured by Shimadzu Corporation: high-sensitivity chemiluminescence NOx meter CLM-500).
And its concentration was measured.

Next, the above-mentioned measurement was carried out for the double base explosives (A, B, C: new in this order) having different storage periods by the explosive stability test apparatus thus constructed. FIG. 4 is a diagram showing a change in electric resistance of the present sensor element with respect to the explosive C. The horizontal axis indicates time (min), and the vertical axis indicates electric resistance (Ω). As is apparent from FIG. 4, the electric resistance of the sensor element is determined by the NOx generated from the explosive.
Immediately after the introduction, it decreased significantly, and then asymptotically approached a certain rate.

FIG. 5 shows, for example, a change in electric resistance immediately after the introduction of NOx generated from explosives A, B, and C.
The result of plotting the rate of change at which the electric resistance becomes 1/10 (that is, the slope of the straight line in FIG. 4) against the NOx concentration measured by the NOx meter is shown. In this figure, the horizontal axis is N
Ox concentration (ppm), vertical axis is electric resistance change rate (min
^-1 ).

As is apparent from FIG. 5, the concentration of NOx generated from the explosive increases with the age of the explosive, and the rate of change in electrical resistance immediately after introduction increases in proportion to the NOx concentration. Therefore, by using the explosive stability testing apparatus of this embodiment, for example, by measuring the rate of change of the electric resistance of the sensor element, it is easy and quick, and also standardized explosive stability independent of human subjectivity Testing can be performed.

In this embodiment, N generated from the explosive is used.
When exposing the gas sensor 10 to Ox, the gas sensor 10 was installed by a carrier gas using NOx generated in the first container 20 in which the explosive sample was sealed without using a configuration in which the explosive sample and the gas sensor 10 were sealed in the same container. Second container 25
This is to prevent the NOx concentration from fluctuating over time.

As a comparative example, as shown in FIG. 6, the double base explosive 31 was placed in a test tube 30 for an abel test, and the gas sensor 10 was fixed.
And sealed. Then, the test tube 30 was immersed in a constant temperature water bath (not shown) and heated at 65 ° C., and the electric resistance change of the gas sensor 10 was measured by an insulation resistance meter (not shown). FIG. 7 shows a change in electric resistance of the present sensor element with respect to the explosive C. The horizontal axis indicates time (min), and the vertical axis indicates electric resistance (Ω).

As is clear from this figure, the electric resistance of the present sensor element did not show a large change for several minutes after heating, and then gradually showed a large decrease. This takes time until the generation rate of NOx from the explosive after heating becomes constant, and it takes time until the generated NOx reaches the gas sensor 10, so that the NOx concentration exposed to the gas sensor 10 becomes constant. This is because it takes time.

Thus, for example, when the stability test of explosive is performed by measuring the rate of change of the electric resistance of the present sensor element, there is an ambiguity depending on which part of the rate of change of the electric resistance is measured. I will. Therefore, in the present invention, it is preferable that the NOx generated from the explosive sample is introduced and flowed to the installation location of the gas sensor by the carrier gas.

Next, a second embodiment of the present invention will be described. FIG. 8 is a view showing an explosive stability test apparatus according to a second embodiment of the present invention. In this embodiment, instead of the first container and the second container in the first embodiment, a stainless steel container 40 shown in FIG. In the stainless steel container 40, as shown in FIG. 8, the first part 4 for sealing the explosive on the glass beads by a partition is used.
1 and a second portion 42 in which the gas sensor 10 is installed. The NOx generated in the first portion 41 is passed through the three-way cock 43 by the carrier gas,
2 or flow out of the container 40.

For the other parts, the same explosive stability testing device as in the first embodiment is used.
The distance between the electrodes shown in FIG. 2 is 50 μm, and the width of the teeth of the comb is 50 μm.
An element in which copper phthalocyanine was vacuum-deposited on a m-shaped comb-shaped electrode substrate was used. Hereinafter, the operation of the explosive stability test apparatus will be described. First, an appropriate amount of glass beads 51 is packed in the first portion 41 of the stainless steel container 40, and 6 g (52) of double base explosive is wrapped in a nylon mesh and placed thereon. The gas sensor 10 is mounted on the second portion 42 of the stainless steel container 40. The stainless steel container 40 was immersed in a thermostatic water bath (not shown) and heated at 65 ° C.

Next, dry air is applied to the first portion 41 as a carrier gas at a rate of 1 L / min.
And let it flow outside the stainless steel container 40,
It was left for 30 minutes (the gas that was flowed at this time was not introduced into the second portion 42). After a lapse of 30 minutes, a gas containing NOx generated from the explosive was introduced into the second portion 42 in which the gas sensor 10 was installed, and a change in electric resistance of the gas sensor 10 was measured by an insulation resistance meter (not shown).

Next, the above-mentioned measurement was carried out with respect to the double base explosives (A, B, C: new in this order) having different storage periods by the explosive stability test apparatus thus constructed. As a result, similarly to the first embodiment, the electric resistance of the present sensor element was significantly reduced immediately after the introduction of NOx generated from the explosive, and thereafter, it was asymptotically approached at a constant rate. In FIG.
The results are plotted against the change in electric resistance immediately after the introduction of NOx generated from the explosives A, B, and C, against the NOx concentration measured by a change speed NOx meter in which the electric resistance becomes 1/10. In FIG. 9, the horizontal axis represents the NOx concentration (pp
m), and the vertical axis indicates the electric resistance change rate (min ^-1 ).

As a result, as is clear from FIG. 9, the relationship that the concentration of NOx generated from the explosive increases with the age of the explosive, and the rate of change in electrical resistance immediately after introduction increases in proportion to the NOx concentration. It is the same as the first embodiment, and the response speed is higher than that of the first embodiment.
It was faster. This is because, in this embodiment, the explosive is heated and the gas sensor 10 is also heated at the same time, whereby the adsorption speed of NOx on the phthalocyanine-sensitive film is increased.

As described above, even when the explosive stability testing apparatus of this embodiment is used, for example, by measuring the change rate of the electric resistance of the present sensor element, it is easy and quick, and the subjective It is possible to perform a standardized stability test of explosives regardless of the above. Next, a third embodiment of the present invention will be described. In this embodiment, as in the first embodiment, the distance between the electrodes shown in FIG.
Using a device in which copper phthalocyanine was vacuum-deposited on a comb-shaped electrode substrate having a comb-shaped electrode having a comb tooth width of 0 μm and a comb tooth width of 50 μm, the same explosive stability test apparatus as that in FIG. 1 was used. However, as a tube for introducing the carrier gas into the first container 20 and the second container 25, a Viton tube or a silicon tube was used.

Next, the operation of the explosive stability test apparatus will be described. As in the first embodiment, first, 6 g (21) of the double base explosive was placed in the first container 20, immersed in the constant temperature water bath 23, and heated at 65 ° C. Next, this first
Dry air (dry) is used as a carrier gas in the container 20.
air) at 1 L / min and allowed to flow,
For 2 minutes (at this time, the flowed gas is in the second container 2
5 has not been introduced). And after 30 minutes,
A gas containing NOx generated from an explosive was introduced into the second container 25 in which the above-mentioned gas sensor 10 was installed, and a change in electric resistance of the gas sensor 10 was measured by an insulation resistance meter 26.

Next, the above-mentioned measurement was carried out for the double base explosives (A, B, C: new in this order) having different storage periods by the explosive stability testing apparatus thus constructed. As a result, similarly to the first embodiment, the electric resistance of the present sensor element was significantly reduced immediately after the introduction of NOx generated from the explosive, and thereafter, it was asymptotically approached at a constant rate. FIG. 10 shows the results of plotting the electrical resistance change immediately after introducing the NOx generated from the explosives A, B, and C against the NOx concentration measured by a change speed NOx meter in which the electrical resistance becomes 1/10. showed that. In FIG. 10, the horizontal axis indicates the NOx concentration (ppm), and the vertical axis indicates the electric resistance change rate (min ^-1 ).

As a result, the viton tube (▲) or the silicon tube (■) is replaced with a Teflon tube (●)
The adsorption of NOx was slightly observed as compared with that of Example 1, and the NOx concentration in the carrier gas was lower than that in the first example. However, as is clear from FIG. The relationship that the rate of change of the electric resistance also increases in proportion to the NOx concentration was established as in the first embodiment.

Therefore, even when the explosive stability testing apparatus of this embodiment is used, the speed of change of the electric resistance of the present sensor element can be measured easily and quickly without depending on human subjectivity. It is possible to conduct a standardized stability test for explosives. Further, the present invention has the following utilization modes. In the above embodiment, a commercially available insulation resistance meter was used as a device for measuring a change in electric resistance of a gas sensor using phthalocyanine as a sensitive film, but the present invention is not limited to this.For example, magnesium phthalocyanine is used as a sensitive film. The electric resistance of the sensitive film is extremely low (approximately 10 ⁶ Ω), and the measurement can be performed with a simple electric circuit.

As a gas sensor, a quartz oscillator is used to measure a change in the oscillation frequency of the quartz oscillator due to gas adsorption to the phthalocyanine sensitive film, or a surface acoustic wave element is used to measure the phthalocyanine reaction film. It is also possible to use a device that measures a change in the oscillation frequency of the surface acoustic wave element due to gas adsorption, and in that case, a device suitable for that is used.

Further, in the first embodiment, a screw-cap glass bottle is used as the first container for sealing the explosive sample, and a stainless steel container is used as the second container for installing the gas sensor. In the second embodiment, the explosive sample is sealed. In addition, although a stainless steel container was used as a container for installing the gas sensor, the present invention is not limited to this as long as it is difficult to adsorb NOx.
However, it is preferable that the container in which the gas sensor is installed is made of metal because it has an electric shielding effect and a light shielding property.

It should be noted that the present invention is not limited to the above embodiment, and various modifications are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[0039]

As described above in detail, according to the present invention, it is possible to use a gas sensor having a phthalocyanine-sensitive film as well as to perform a simple and quick standardized test independent of human subjectivity. Thus, it is possible to provide an explosive stability test apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an explosive stability test apparatus showing an embodiment of the present invention.

FIG. 2 is a plan view of a gas sensor of the explosive stability test apparatus according to the embodiment of the present invention.

FIG. 3 is a configuration diagram of a second container of the explosive stability test apparatus according to the embodiment of the present invention.

FIG. 4 is a diagram showing a change in electric resistance of the present sensor element with respect to an explosive C according to the embodiment of the present invention.

FIG. 5 is a graph showing an example of the present invention, in which a change rate at which the electric resistance becomes 1/10 with respect to the electric resistance change immediately after introducing NOx generated from explosives A, B, and C is measured by a NOx meter.
It is a figure which shows the result plotted with respect to Ox density | concentration.

FIG. 6 is a view showing a state in which a double base explosive is sealed in a test tube for an abel test.

7 is a diagram showing a change in electric resistance of the gas sensor with respect to the explosive C according to FIG. 6;

FIG. 8 is a view showing an explosive stability test apparatus according to a second embodiment of the present invention.

FIG. 9 shows a second embodiment of the present invention, in which a change in the electric resistance immediately after introducing NOx generated from explosives A, B, and C was measured with a change speed NOx meter in which the electric resistance becomes 1/10. It is a figure which shows the result plotted with respect to NOx concentration.

FIG. 10 shows a third embodiment of the present invention, in which a change in electric resistance immediately after introducing NOx generated from explosives A, B and C is measured by a change speed NOx meter in which the electric resistance becomes 1/10. It is a figure which shows the result plotted with respect to NOx concentration.

[Explanation of symbols]

REFERENCE SIGNS LIST 10 gas sensor 11 glass substrate 12 connection terminal of comb-shaped electrode 13 comb-shaped electrode 14 copper phthalocyanine-sensitive film 20 first container 21, 52 double base explosive 22, 51 glass beads 23 constant temperature water tank 24 tube (Teflon tube) 25 second container 25 a gas inlet 25b gas outlet 26a leads 26 insulation resistance meter 27 recorder 28 NOx analyzer 28A NO ₂ -NO converter 28B NOx detector 40 a stainless steel vessel 41 first portion 42 second portion 43 3 way stopcock

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Minoru Saito 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd. (72) Inventor Katsutaki Kaibu 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd. (72) Inventor Toyosaku Sato 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd. (72) Inventor ▲ Mano Kunihiko 1-7-7 Toranomon, Minato-ku, Tokyo No. 12 Oki Electric Industry Co., Ltd. (72) Inventor Seigo Ohno 4-16-36 Shibaura, Minato-ku, Tokyo Oki Engineering Co., Ltd. (58) Field surveyed (Int.Cl. ⁶ , DB name ) G01N 27/12 G01N 31/00 G01N 33/22

Claims (6)

(57) [Claims] (A) a first container in which an explosive sample is sealed;
(B) a second container provided with a gas sensor using a phthalocyanine as a sensitive film, (c) a constant temperature bath for heating the first container, and (d) a carrier gas in the first container and the second container. An explosive stability testing apparatus, comprising: tubes to be introduced / flowed; and (e) a device for measuring a change in characteristics of the gas sensor. 2. A container in which a gas sensor having a phthalocyanine-sensitive film as a sensitive film is disposed and a gunpowder sample is sealed; (b) a thermostatic bath for heating the container; and (c) a carrier in the container. An explosive stability test apparatus comprising: tubes for introducing and flowing gas; and (d) a device for measuring a change in characteristics of the gas sensor. 3. The explosive stability test apparatus according to claim 2, wherein the container is divided into a first portion in which the explosive sample is sealed and a second portion in which the gas sensor is installed, and the carrier gas is supplied to the three-way portion. Second from said first part through a cock
An explosive stability testing device characterized in that it is introduced into a part or flows out of the container. 4. The explosive stability testing apparatus according to claim 1, wherein the gas sensor measures a change in electrical characteristics of the phthalocyanine-sensitive film due to gas adsorption to the phthalocyanine-sensitive film using a pair of electrodes. An explosive stability testing device characterized by the following: 5. The explosive stability testing device according to claim 4, wherein the electrode is a comb-shaped electrode. 6. The explosive stability testing device according to claim 1, wherein the tubes are a Teflon tube, a viton tube, or a silicon tube.