JPS609600Y2 - blasting equipment - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of explosives used for detecting residual explosives in blasting methods.
-5780 Mine Publication and Japanese Patent Application No. 1983-4277
In Publication No. 1-79713, etc., a cylindrical permanent magnet or an elongated rod-shaped permanent magnet is loaded together with an explosive into an explosive loading hole, and the magnetic flux of the permanent magnet remaining after blasting is detected using a magnetic detector to identify unexploded explosives. We have proposed a method to discover.

To explain an example of the method for detecting residual explosives proposed by the inventors of the present invention, as shown in FIG.
After inserting the permanent magnet C into the innermost part of the explosive loading hole provided in the On the other hand, permanent magnet C remaining on face a by magnetic detector
The purpose is to detect residual explosives by detecting the magnetic flux emitted from them.

At this time, if the explosive d loaded into the explosive loading hole is completely exploded, the permanent magnet will be destroyed and no magnetic flux will be detected from the face, and if there is any unexploded explosive remaining. Since there is always a permanent magnet inserted in the deepest part of the explosive loading hole, residual explosives can be discovered by detecting the magnetic flux emitted from this remaining permanent magnet with a magnetic detector. It is possible.

However, in the above method, a part of the destructive force at the time of blasting against the permanent magnet C also acts in the excavation direction as shown by the arrow in Figure 1. Fragments e of the permanent magnets often adhere and remain.

For this reason, although the amount of magnetic flux emitted from the fragment C' is extremely small, when a magnetic detector is brought very close to the fragment for exploration, it may exhibit a reaction as if it had detected the presence of residual explosives.

This is different from displaying that there is no residual explosive even though it is present, and is a safer display, so from a safety standpoint, it is not a problem, but if such a phenomenon occurs many times. In this case, it is necessary to reconfirm the status of all the points where a reaction occurred, resulting in a decrease in work efficiency.

The present invention aims to eliminate such defects by enveloping at least one end face of a permanent magnet, which has a low electrical resistance and whose surface is coated with an electrically insulating material, and the entire circumferential side surface connected to the end face with an explosive. The inverted permanent magnet-containing explosive is loaded into the deep part of the explosive loading hole so that the L end face of the permanent magnet faces the deep part, and the explosive is placed behind the permanent magnet-containing explosive in the explosive loading hole. The purpose of this blasting device is to prevent permanent magnet fragments from remaining on the blasting face when the explosive loaded in the explosive loading hole is completely detonated. An object of the present invention is to provide an improved blasting device configured to accurately detect residual explosives.

As described above, the permanent magnet-containing explosive used in the blasting device according to the present invention is constructed by covering at least one end face of a permanent magnet and the entire circumferential side surface connected to the end face with explosive, and the present blasting device This permanent magnet-containing explosive is loaded into the deep part of the explosive loading hole so that one end face of the permanent magnet faces the closed part in the deep part, and the permanent magnet-containing explosive corresponding to the other end face of the permanent magnet is loaded into the deep part of the explosive loading hole. Since the explosives were sequentially set in the explosive loading hole at the rear, the destructive force against the permanent magnet during blasting did not act only in the excavation direction of the face, and therefore the remains of the permanent magnet remained in the deep part of the explosive loading hole. This solves the problem of residual magnetic flux even though the explosion is complete.

Furthermore, if the permanent magnet is incorporated into the explosive in advance during the explosive manufacturing stage, the effort of inserting the permanent magnet into the explosive loading hole can be saved compared to the above-described method.

There are the following types of permanent magnets that are incorporated into explosives, and they have low electrical resistance and exhibit the properties of metal.

Inserting metal into explosives is originally prohibited for security reasons.

This is because there are large construction machines such as rock drills and power shovels at excavation sites, and many power transmission cables are installed, and the current flowing through these cables generates a magnetic field.Changes in this magnetic field cause the metal magnet to An induced current flows.

Therefore, in the present invention, when a permanent magnet with low electrical resistance and exhibiting the properties of a metal body is incorporated into an explosive, the surface of the permanent magnet is coated with an electrically insulating material, so that the surface of the permanent magnet has a high electrical resistance. providing an electrical insulating material, which prevents the induced current flowing through the permanent magnet from flowing to the explosive covering the outer surface of the electrical insulating material having high electrical resistance, thereby eliminating the adverse effects of the induced current in the permanent magnet; This makes it possible to use the explosive in a state where the risk of explosion of the explosive is eliminated.

A magnet composed of a permanent magnet and an electrically insulating material is disclosed in Japanese Patent Application Laid-Open No. 87007/1987 as a so-called flexible vinyl magnet.

However, the same flexible vinyl magnet is a magnet in which magnetic powder is kneaded into a flexible rubber-like material, and therefore, the magnetic powder on the outer circumferential surface of the magnet has the same degree of dispersion as the magnetic powder inside the magnet. The magnetic powder exists with a degree of dispersion, and there are portions of the magnetic powder on the outer peripheral surface of the magnet that are not covered with the flexible rubber-like material.

Therefore, when the flexible vinyl magnet is assembled and brought into contact with an explosive, the portion of the outer peripheral surface of the flexible vinyl magnet that is not covered with the rubbery material of the magnetic powder comes into contact with the explosive, and an induced current flows in the magnetic powder. Furthermore, if the induced current flows to the explosive, there is a risk that the explosive will explode.

However, in the present invention, as described above, the surface of the permanent magnet is coated with an electrically insulating material, so the adverse effects of the induced current in the permanent magnet are eliminated, and the risk of the explosive exploding is eliminated.

The present invention will be described below with reference to the illustrated embodiments.

In Figure 3, 1 has a diameter of 2577!171 and a length of 140m.
, with a diameter of 1077B and a length of 1 along its central axis.
3orIr! A rod-shaped permanent magnet 2 with a small electrical resistance and whose surface is coated with an electrically insulating material is inserted, and the explosive 1
The end face of the permanent magnet 2 is exposed only on one end face of the permanent magnet 2, and the other end of the permanent magnet 2 is covered with the explosive 1.

The explosive 1 into which the permanent magnet 2 is inserted is placed in the deep part of the explosive loading hole 4 provided in the face 3, as shown in FIG. The explosive 5, the detonator 6, and the fuse 7 are sequentially set behind it, and the explosive loading hole 4 is closed with sand 8.

In this case, it is desirable that the side of the explosive 1 where the end face of the permanent magnet 2 is exposed is oriented toward the open end of the explosive loading hole 4.

Therefore, since a destructive force as shown in Q is applied to the permanent magnet 2, the phenomenon of permanent magnet fragments remaining on the face after blasting is eliminated.

In addition, in the above explosive, the ratio of the diameter of the magnet to the cartridge is 0.3.
~0.5 is desirable, and at least 1 from the tip of the medicine package.
It is desirable to separate the tips of the inserted magnets by approximately -.

5 and 6 respectively show other embodiments of the explosive according to the present invention. In the embodiment shown in FIG. 5, the explosive 1 has a small electrical resistance and its surface is coated with an electrically insulating material. The entire permanent magnet 2 is buried, and furthermore, in the embodiment shown in FIG. 6, a plurality of permanent magnets 2 having low electrical resistance and whose surfaces are coated with a military insulating material are embedded at predetermined intervals along the central axis within the explosive 1. It is buried in each.

As mentioned above, in this blasting device that uses explosives containing permanent magnets that have low electrical resistance and whose surfaces are coated with an electrically insulating material, there is a risk that the permanent magnets will generate heat, but as shown in Figures 7 and 8. The on-site work examples shown in Figures 9 and 10 demonstrate that there is no such fear.

FIG. 7 is a plan view of the underground mine 20 at the time when the drilling of the explosive loading hole in the face 21 has been completed. Under this underground state, the equipment is carried into the underground from outside the mine, and is inserted into the explosive loading hole 22 in the working face 21. A blasting device consisting of explosives was charged.

In this case, the time required to process the blasting device outside the mine is approximately 3 blows, and the time required to transport the explosive 23 underground from the mine entrance to the face is approximately 1 powder, and the state during transportation is as shown in Figure 10. The explosives 23 were conveyed along a path from the mine entrance to the face that was contained within the magnetic field generated by the lighting wiring 24.

In addition, the charging of the blasting device consisting of the explosives 23 and the like into the explosive loading hole 21 was carried out within a magnetic field generated by the lighting wiring 24, and the required time was about 40 minutes to 5 inches. .

FIG. 8 is a vertical cross-sectional view of the mine at the time of blasting, and in this state underground, the explosives 23, etc. remaining in the face are in the magnetic field generated by the lighting wiring 24 at various places in the mine and the power source inside the scraper 25. The residual time of the blasting device or explosives 23 remaining on the face in this magnetic field is the sum of the time required to remove the debris and the processing time of the remaining device or explosives 23 itself, and is about 120 minutes to 15 minutes. Met.

FIG. 9 is a vertical cross-sectional view of the mine at the time when the sludge is being removed, and this underground state shows that the power source inside the slough remover 25 at the time of the blasting shown in FIG. This is the situation when the device or the explosive 23 gets closer and closer, and the magnetic field from the same power source to the device or the explosive 23 becomes even stronger.

FIG. 10 shows the state of underground transportation of the blasting device or explosives 23 on the path from the mine entrance to the face, and the environmental conditions on the same path.

In the above-mentioned field work, the permanent magnet, which is placed in an explosive and has a low electrical resistance and whose surface is coated with an electrically insulating material, is left in the face after being processed by the blasting equipment outside the mine, through the underground state shown in Figure 9. During the entire time until the disposal of the same explosive 23 was completed, no accidents caused by heat generation due to induced current occurred.

In addition, when the magnet arrived at the face after being transported from outside the mine into the mine, we examined the state of heat generation by touching it with our fingers, but we could not detect any heat generation from the magnet.

In the figure, 26 is a trolley, 27 is a trolley drive vehicle, and 28
29 is a hole drilling machine, 29 is a floodlight, 30 is a scrap, and 23' is a residual explosive.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an example of the blasting method, Fig. 2 is a longitudinal sectional view showing the state of the face after blasting, and Fig. 3A is a vertical sectional view showing the state of the face after blasting. A vertical cross-sectional view showing one embodiment, FIG. 3B is a view taken from arrow A in FIG. 3A.
- Figures A and 4 are longitudinal cross-sectional views showing one embodiment of the blasting device according to the present invention, and Figures 5A and 6A are longitudinal cross-sectional views showing other embodiments of the permanent magnet-containing explosive, respectively; 5B and 6B respectively show an arrow view C-C in FIG. 5A, an arrow EE view in FIG. 6A, and FIGS. 7 to 10 show examples of on-site construction of the present blasting device, Figure 7 is a plan view of the mine after the drilling of the face has been completed, Figure 8 is a vertical cross-sectional view of the mine at the time of blasting, Figure 9 is a vertical cross-section of the mine at the time of sludge removal, and Figure 10 shows the state of transport of explosives into the mine. It is a longitudinal side view of the mine shown. 1... Explosives, 2... Permanent magnets with low inherent electrical resistance and whose surfaces are coated with an electrically insulating material, 4
...Explosive loading hole, 5...Explosive.

Claims (1)

[Scope of utility model registration request] Explosives containing permanent magnets, which are made by covering at least one end face of a permanent magnet with low electrical resistance and whose surface is coated with an electrically insulating material, and the entire circumferential side surface connected to the end face, are inserted deep into the explosive loading hole. A blasting device characterized in that the permanent magnet is loaded in the recess so that the l end face faces the inner part, and explosives are sequentially set behind the permanent magnet-containing explosive in the explosive loading hole.