JP5839284B2 - γ-ray reflection measuring device - Google Patents

Description

  The present invention relates to a level measurement of a liquid or a powder, a level switch, or a measurement object in a container, which is measured by using a measuring instrument equipped with γ rays in chemical, paper pulp, steel, non-ferrous plant, civil engineering field, etc. It can be used for a density meter that measures the bulkiness of the pipe, a pipe density meter, a thickness meter that measures a plate, and the like.

  For example, a radiation source shielding block device described in Japanese Patent Application Laid-Open No. 2009-53127 includes a first radiation source shielding block, a disk-shaped radiation source mounting block provided in a hole of the block, and the radiation source. A radiation source storage section provided in the mounting block, a rotation mechanism that rotates the radiation source storage section, and a second radiation source shielding block that shields the opening of the first radiation source shielding block. Is done. The first radiation source shielding block is provided with a hole opened only on one side surface. A disk-shaped radiation source mounting block is rotatably mounted via a rotation shaft inside the hole of the first radiation source shielding block. The disk-shaped radiation source mounting block can be partially protruded from the inside of the first radiation source shielding block by rotating in the hole in the first radiation source shielding block. It has become.

JP 2009-53127 A

  The radiation source shielding block device described in the patent document has a configuration in which a part of the radiation source shielding block can protrude from the inside of the radiation source shielding block by rotating the radiation source in a hole in the radiation source shielding block. It has become. The radiation source shielding block having the above-described configuration is configured such that the radiation source protrudes from the inside to the outside during use, and the radiation source is stored in the center of the interior when not in use.

  The radiation source shielding block device described in the above-mentioned patent document requires storage when the radiation source is used and when it is not used, and has no consideration for γ-ray calibration. The conventional γ-ray measuring device is a standard for automatic calibration of the γ-ray detector from the main beam, for example, when it is difficult to enter the amount of beam necessary to discriminate the wave height into the γ-ray detector. In order to make the beam necessary for taking the reference incident on the γ-ray detector, an auxiliary radiation source is arranged in the vicinity of the γ-ray detector, and the beam of the necessary amount is incident and used. For this reason, two γ-ray sources for measurement and reference are required, and not only the acquisition and disposal of the γ-ray source is costly, but also much labor is required for manufacturing and calibration.

  In order to solve the above problems, the present invention provides a main beam composed of the same radiation source and an auxiliary beam smaller than the output of the main beam without using another auxiliary beam different from the main beam as a radiation source. An object of the present invention is to provide a γ-ray reflection type measuring apparatus using the above. Another object of the present invention is to provide a γ-ray reflection type measuring apparatus that reduces the cost of obtaining or discarding a new auxiliary radiation source, and at the same time omits the labor of manufacturing or calibration and further improves usability. .

(First invention)
The γ-ray reflection type measuring apparatus of the first invention is a device for measuring the thickness, density, level, bulkiness, etc. of an object to be measured using γ-rays, and a γ-ray generating unit for generating the γ-rays, A main beam emission hole that emits γ-rays generated from the γ-ray generation unit, an auxiliary beam emission hole that emits an auxiliary beam having a smaller output than the main beam generated from the γ-ray generation unit, and the respective emission holes And a shielding body that shields the γ-ray generator, and a γ-ray detector that directly detects the main beam and the auxiliary beam reflected from the object to be measured.

(Second invention)
In the γ-ray reflection type measuring apparatus according to the second invention, a shielding body for adjusting the output of the auxiliary beam is provided between the auxiliary beam emission hole and the γ-ray source detector. .

(Third invention)
In the γ-ray reflection type measuring apparatus of the third invention, the auxiliary beam emitting hole is provided with an angle with respect to the reference surface with respect to the reflection surface of the object to be measured.

  According to the present invention, it is possible not only to reduce the cost for separately obtaining the auxiliary radiation source and the cost for performing disposal, but also to eliminate a great deal of labor for manufacturing or calibration.

  According to the present invention, a shielding body for adjusting the strength of the auxiliary beam is provided between the auxiliary beam emission hole and the γ-ray detector, or a shielding body having a different thickness, or a different size for the shielding body. By providing a small hole, it is possible to easily adjust the intensity of the auxiliary beam or generate a plant control signal even when the half-life of the radiation source is reached.

  According to the present invention, the distance between the object to be measured and the γ-ray detector can be increased by providing the emission hole for emitting the auxiliary beam at an angle with respect to the reflection surface of the object to be measured. Even if the object to be measured has a heat source, correct measurement is possible and the γ-ray detector can be easily protected from the heat source.

(First invention)
The first invention is a γ-ray reflection type measuring apparatus that measures the thickness and / or density of a measurement object, the level or bulkiness of the measurement object filled in a container, and the like. Examples of the object to be measured include chemicals, paper pulp, steel and non-ferrous plants, and liquids or powders on the civil engineering site. The measurement device equipped with the γ-ray source is a level measurement of a liquid or powder in a container, a level switch, or a density meter that measures the bulk of a measurement object in the container, a pipe densitometer, or a thickness of a plate or the like. It can be used for thickness gauges that measure thickness.

  The γ-ray reflection type measurement apparatus of the present invention includes a γ-ray generation unit that generates a main beam and an auxiliary beam, a main beam emission hole that radiates the main beam, an auxiliary beam emission hole that radiates an auxiliary beam, And a γ-ray detector for detecting the reflected beam and the auxiliary beam of the main beam.

  The γ rays are emitted from the γ ray generator as the main beam to the object to be measured through the main beam emission hole. The γ-rays are radiated from the γ-ray generation unit as an auxiliary beam having a smaller output than the main beam through the auxiliary beam emission hole. The main beam emission hole and the auxiliary beam emission hole radiate the main beam and auxiliary beam generated by the γ-ray generation unit in directions different from each other by 90 degrees. Each of the emission holes and the γ-ray generator is composed of a γ-ray shielding body, and radiates γ-rays in a predetermined direction at the time of measurement.

  The γ-ray detector detects a main beam reflected from the object to be measured and an auxiliary beam directly emitted. The γ-ray detector automatically calibrates the detector based on the photo peak generated by discriminating the height of the auxiliary beam, and fills the thickness, density, and container of the object to be measured by increasing or decreasing the reflected main beam. The level or bulkiness of the measured object can be measured.

(Second invention)
In the γ-ray reflection type measuring apparatus according to the second invention, a shielding body for adjusting the output of the auxiliary beam is provided between the auxiliary beam emission hole and the γ-ray detector. The shielding body for adjusting the output adjusts the intensity of γ-ray, and the γ-ray detector can be calibrated. By preparing a plurality of the shields, it is possible to cope with changes in radiation intensity. In addition, a plurality of holes of different sizes or thicknesses can be provided in the discharge holes provided in the shielding body, and the intensity of radiation can be changed by selecting these holes.

(Third invention)
In the γ-ray reflection type measuring apparatus according to the third aspect of the invention, the auxiliary beam emission hole is provided at an angle with respect to the reference surface with respect to the reflection surface of the object to be measured. By providing an angle between the auxiliary beam emission hole and the measurement object reference plane, the position of the γ-ray detector can be lifted upward. The γ-ray detector is placed at an upper position away from the object to be measured. When the object to be measured is a heat source, it can be protected from the heat source. The said angle can change the distance from a heat source by making it thin or thick.

FIG. 2 is a schematic diagram for explaining an embodiment of the present invention, and is a γ-ray composed of a shielding body provided with both an emission hole for emitting a main beam from a γ-ray source and an emission hole for emitting an auxiliary beam smaller than the main beam. It is a figure for demonstrating a reflection type measuring device. Example 1 It is a schematic diagram for demonstrating 2nd Example of this invention, and is a figure for demonstrating the example which divided the shielding body into two and attached to the detector side as another body. (Example 2) It is a schematic diagram for demonstrating the example in the case of aiming at the thickness of a to-be-measured object in the Example of this invention. It is a schematic diagram for explaining a third embodiment of the present invention, and is a diagram for explaining an example in which a shielding body for adjusting the auxiliary beam is provided between the auxiliary beam emitting hole and the detector. (Example 3) FIG. 10 is a schematic diagram for explaining a fourth embodiment of the present invention, in order to explain an example in which an auxiliary beam emission hole is provided at an angle with respect to the reference surface with respect to the reflection surface of the object to be measured; FIG. Example 4

  FIG. 1 is a schematic diagram for explaining an embodiment of the present invention. From a shielding body provided with both an emission hole for emitting a main beam from a γ-ray source and an emission hole for emitting an auxiliary beam smaller than the main beam. It is a figure for demonstrating the gamma ray reflection type | mold measuring device which becomes. In FIG. 1, the γ-ray reflection type measuring apparatus has a shielding body 1 containing a γ-ray source 4, a main beam emission hole 2 for radiating a main beam 5 from the γ-ray source 4, and a smaller output than the main beam 5. It comprises an emission hole 3 for emitting radiation, and a γ-ray detector 8 for detecting a reflected beam 6 and an auxiliary beam 7 reflected from the object to be measured.

  The γ-ray reflection type measuring apparatus shown in FIG. 1 is, for example, the amount of liquid, powder, foam, etc. in the tank of the large reaction vessel 9, or the amount of liquid, powder, foam, etc. in the pipe, the liquid level, The density, bulkiness, etc. can be detected by the γ-ray detector 8. The γ-ray detector 8 can measure the liquid, powder, foam, etc. in the tank of the large reaction vessel 9 or the liquid, powder, foam, etc. in the pipe regardless of the size of the container. . The auxiliary beam emitting hole 3 is designed so that the output is reduced by changing the size (cross-sectional area). The auxiliary beam 7 radiated from the auxiliary beam emission hole 3 is detected by a γ-ray detector 8 and compared with the main beam 6 reflected from the liquid or the like, thereby accurately determining the density, bulkiness, level, etc. of the liquid. Can be measured. The radiated main beam 5 hits an object to be measured in the container 9 and is reflected to become a reflected beam 6.

  FIG. 2 is a schematic diagram for explaining a second embodiment of the present invention, and is a diagram for explaining an example in which the shielding body is divided into two parts and is attached to the detector side as a separate body. 2 differs from FIG. 1 in that a separate shielding body 12 is placed between the shielding body 1 and the γ-ray detector 8. The separate shielding body 12 is provided with an auxiliary beam emission hole 3. The size of the auxiliary beam emission hole 3 is the same as that shown in FIG. The separate shield body 12 is made of the same material as the shield body 1.

  FIG. 3 is a schematic diagram for explaining an example in which the thickness of the object to be measured is set according to the embodiment of the present invention. The example shown in FIG. 3 is an example in which the object to be measured is a plate-like one, and the other parts are the same as those in FIG.

  FIG. 4 is a schematic diagram for explaining a third embodiment of the present invention, for explaining an example in which a shielding body for adjusting the auxiliary beam is provided between the auxiliary beam emission hole and the γ-ray detector. FIG. In FIG. 4, the auxiliary beam adjusting shielding body 11 is made of the same material as the shielding body 1, and is made of various metals such as aluminum, iron, brass, copper, lead, tungsten, and other various inorganic materials or various glasses. Further, various composite materials such as those obtained by adding various materials to various plastics can be used.

  The auxiliary beam adjusting shielding body 11 is adjusted so as to have an inclination with respect to the thickness of the shielding body, or adjusted according to the half-life by providing small holes of different sizes, or plant control. The above test signals can be generated. The auxiliary beam adjusting shield 11 can also be used as an auxiliary beam shutter. When the measurement is performed by comparing the reflection of the main beam 6 and the auxiliary beam 7, the shutter can be opened and closed to see the ratio between the two.

  FIG. 5 is a schematic diagram for explaining a fourth embodiment of the present invention, in which an auxiliary beam emission hole is provided at an angle with respect to the reference surface with respect to the reflection surface of the object to be measured. It is a figure for demonstrating. In FIG. 5, when the temperature of the measurement target is high, it is necessary to separate the measurement target by a certain distance in order to protect the γ-ray detector 8. As shown in the figure, the auxiliary beam emission hole 3 is provided so as to be directed upward at an angle. Since the γ-ray detector 8 can arbitrarily arrange the height of the auxiliary beam emission hole 3, measurement with various measurement objects such as the vicinity of a high heat source is possible.

  As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to the said Example. The present invention can be modified in various ways without departing from the scope of the claims. For example, known types can be arbitrarily used as the type of radiation source, the material of the shielding body, the size and shape of the shielding body and the emission hole, and the γ-ray detector.

DESCRIPTION OF SYMBOLS 1 ... Shield body 2 ... Main beam emission hole 3 ... Auxiliary beam emission hole 4 ... Radiation source 5 ... Main beam 6 ... Reflection beam 7 ... Auxiliary beam 8 ... γ-ray detector 9 ... container wall (pipe wall)
11 ... Auxiliary beam adjustment shield body 12 ... Separate shield body 13 ... Plate-shaped member

Claims (2)

In a γ-ray reflection type measuring device that measures the thickness, density, level, bulkiness, etc. of an object to be measured using γ-rays,
A γ-ray generator that generates the γ-ray;
A main beam emission hole that emits γ-rays generated from the γ-ray generation unit;
With respect to the reflection surface of the object to be measured, an angle is provided in a direction away from the main beam emission hole with respect to the reference surface, and the output is smaller than that of the main beam generated from the γ-ray generation unit. An auxiliary beam emitting hole for emitting an auxiliary beam;
A shielding body that shields each of the emission holes and the γ-ray generation unit;
A γ-ray detector that automatically calibrates a photo peak generated by discriminating the height of the auxiliary beam while directly detecting the main beam and the auxiliary beam reflected from the object to be measured;
A γ-ray reflection type measuring apparatus comprising at least The γ-ray reflection type measurement according to claim 1, wherein a shielding body for adjusting an output of the auxiliary beam is provided between the auxiliary beam emission hole and the γ-ray source detector. apparatus.

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