JP2986465B1 - Melt flow velocity measurement channel - Google Patents

Abstract

An object of the present invention is to easily and surely secure a plurality of thermocouples at a predetermined insertion depth on a side surface of a measuring pipe having a small diameter and a long length, and to easily secure airtightness in a mounting portion thereof. SOLUTION: The measuring pipe 60 having a small diameter and a long length into which a melt enters, and a cylindrical structure having a parallel flat surface on an outer peripheral portion are formed and fixed to respective thermocouple mounting positions on the outer circumference of the measuring pipe. A plurality of thermocouple mounting members 62 and a plurality of thermocouples 68
Is provided. A through-hole is formed from one flat surface of the thermocouple mounting portion to penetrate the thermocouple mounting portion and the measurement pipe, and the inner surface of the through-hole is threaded, and compression fitting (compression mounting) is performed using the screw hole 64. Each thermocouple sheath is hermetically attached by a metal fitting 66.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a channel for measuring the flow velocity and temperature of a melt entering a small-diameter and long measuring pipe with a large number of thermocouples. Attach a thermocouple mounting member to the outer periphery of
The present invention relates to a channel for measuring a flow velocity of a melt in which each thermocouple is airtightly attached by a compression fitting. This technique is useful, for example, for fluid measurement in a melt solidification behavior test device.

[0002]

2. Description of the Related Art Elucidation of solidification phenomena along a dispersion path of a melt is important in various engineering fields such as nuclear engineering, and many tests for simulating the phenomena have been carried out. This type of test simplifies the test system that simulates the dispersion path, eliminates the uncertainty of the test data due to the shape, facilitates the extraction of the parameters that characterize the phenomenon, and improves the solidification process. It is important to understand the flow situation and to understand the solidification heat transfer phenomenon. For that purpose, it is necessary to stably measure the flow velocity of the melt with high accuracy.

As shown in FIG. 5, a test part is constituted by a measuring pipe 10 having a small diameter (for example, a minimum diameter of 9 mm) and a long length (several meters, for example, about 4 m) as shown in FIG. There is a structure in which the flow rate of the melt is determined by detecting the temperature rise of each part due to the melt penetrating into the measuring pipe 10. The temperature is measured by a large number of thermocouples 12 attached to the side of the measuring pipe 10.

Conventionally, this thermocouple is mounted by directly drilling small through-holes (for example, about 1.6 mm in diameter) at predetermined positions on the side surfaces of a small-diameter and long measuring pipe, and each of the through-holes. 1
4 was performed by inserting the tip of the thermocouple 12 and bonding it. The bonding portion is indicated by reference numeral 16.

[0005]

However, the conventional structure as described above has the following problems. Since the measuring pipe is thin, long, and thin, it is extremely difficult to form a minute through hole in the side surface. Since the thermocouple must be supported by the thin side of the measuring pipe, its support is unstable and uncertain, making it difficult to set the thermocouple mounting depth strictly. It is difficult to ensure airtightness. Since the intervals at which a plurality of thermocouples are installed are determined by the predicted solidification position of the melt, the thermocouple mounting processing positions differ depending on the test conditions, and the test preparation process becomes longer.

SUMMARY OF THE INVENTION It is an object of the present invention to be able to easily and reliably mount a plurality of thermocouples at a predetermined insertion depth on the side of a small-diameter and long measuring pipe, and to easily seal the air at the mounting portion. An object of the present invention is to provide a melt flow velocity measurement channel that can be secured. Another object of the present invention is to provide a melt flow velocity measurement channel that is devised so that it can easily cope with a case where a thermocouple mounting position is different depending on test conditions.

[0007]

According to the present invention, there is provided a measuring pipe having a small diameter and a long length into which a melt enters, and a cylindrical structure having a parallel flat surface on an outer peripheral portion. A plurality of thermocouple mounting members fixed to each thermocouple mounting position,
A plurality of thermocouples are provided, a through hole is formed from one flat surface of the thermocouple mounting portion to penetrate the thermocouple mounting portion and the measurement pipe, and the inner surface of the through hole is subjected to thread processing, and the screw hole is formed. A channel for measuring the flow velocity of the melt, which is used to hermetically attach each thermocouple sheath by a compression fitting (compression fitting). The present invention is based on the idea of `` drilling a hole in the measurement pipe itself '' of the prior art, and converting it to an idea of `` fixing a thermocouple mounting member to the outer circumference of the measurement pipe and processing and attaching a thermocouple '', The present invention has solved the above technical problem and is characterized by this point.

The present invention also provides a measuring pipe having a small diameter into which a melt enters, and a cylindrical structure having a parallel flat surface on the outer peripheral portion, which is fixed to each thermocouple mounting position on the outer circumference of the measuring pipe. A plurality of thermocouple mounting members, and a plurality of thermocouples, and a through hole passing through the thermocouple mounting portion and the measurement pipe from one flat surface of the thermocouple mounting portion, and the inner surface of the through hole. Each thread is subjected to screw processing, and each thermocouple sheath is hermetically attached by compression fitting using the screw holes to form a measurement channel module.A plurality of the measurement channel modules are hermetically connected in tandem with tube joints. This is the melt flow velocity measurement channel. In that case, a plurality of types of measurement channel modules having different thermocouple mounting intervals (specifically,
It is preferable to use the standardized measurement channel modules or measurement pipe modules without thermocouples in combination and connect them to one as needed. By modularizing the measurement channels and interconnecting them with tube joints, the measurement channels provided with thermocouple mounting members at positions suitable for the purpose of the test can be easily and quickly assembled.

The compression fitting used in the present invention comprises, for example, a mounting screw portion screwed into a screw hole of a thermocouple mounting member, a holding screw portion through which a thermocouple sheath penetrates the center, and a pressing screw portion which is tightened to the mounting screw portion. A fitting ferrule which is located on the outer periphery of the sheath and which is compressed and deformed by the mounting screw portion, the holding screw portion, and the thermocouple sheath to maintain an airtight state.

[0010]

FIG. 4 shows an embodiment of a melt flow rate test apparatus to which the present invention is applied. A heater container 24 is installed in a pressurized container 22 provided with a pressure gauge 20, and the heater container 2
The molten sample 26 is accommodated in 4. In the heater container 24,
The side heater 28 and the bottom heater 30 are attached. The two riser portions 34 are raised from the vicinity of the bottom in the heater container 24 to reach the lid 32 of the pressurized container 22, and the riser portion heaters 36 are wound respectively. The measurement channel 40 and the non-measurement channel 42 are connected to the upper ends of both riser portions, respectively, and connected to a drain container 48 having a pressure gauge 46 via a ball valve 44. A plurality of thermocouples 50 are dispersedly arranged at predetermined positions in the measurement channel 40. An electromagnetic flowmeter 52 is installed near the lower end of the measurement channel 40.

After the molten sample 26 is melted in the heater container 24, the melt enters the measurement channel 40 and the non-measurement channel 42 using the pressure of the inert gas filled in the pressurized container 22 as a driving pressure. Let it. Each channel simulates a structure under test (for example, a core structure of a nuclear reactor), and the melt that has entered therein is cooled by turbulent heat conduction and solidified and closed.

In the present test apparatus, the measurement can be performed with the melt flow rate as a parameter by adjusting the pressure of the inert gas charged into the pressurized container 22. The measurement channel 40 and the non-measurement channel 42 have a small diameter so that the penetration distance is not excessively large. Since both channels have a small diameter, it is possible to regard the flow as approximately one-dimensional and to use the melt speed in the axial direction as a representative parameter in grasping the flow state.

The driving pressure is monitored by a pressure gauge 20 attached to the pressure vessel 22, and the temperature of the melt is monitored by a thermocouple (not shown) inserted into the heater vessel 26. The flow rate of the melt is measured by the response of a plurality of thermocouples 50 attached to the inner surface of the measurement channel 40, and the penetration distance of the melt is measured by a solidified block position that can be observed by disassembling the channel after the test. In the test apparatus, the present invention eliminates the need for processing the thermocouple mounting portion on the measurement channel and can measure the flow velocity change leading to solidification blockage with higher accuracy. An electromagnetic flowmeter is installed near the lower end of the channel.

[0014]

FIG. 1 is an explanatory view showing one embodiment of a channel for measuring melt flow according to the present invention. As shown in FIG. 1A, a small-diameter and long measuring pipe 60 into which a melt (molten sample) enters, and a large number of thermocouple mounting members 62 having a cylindrical structure having a parallel flat surface on the outer peripheral portion. Is provided. Here, the thermocouple mounting member has a structure in which a surface excluding a parallel flat surface is a curved surface (in other words, a structure in which a part of a cylindrical surface is cut off), but may have a structure such as a square cylindrical surface or a hexagonal cylindrical surface. Each thermocouple mounting member 62 is fixed to a predetermined thermocouple mounting position on the outer periphery of the measuring pipe 60 by welding or the like. Then, a through hole is provided so as to penetrate the thermocouple mounting member 62 and the measurement pipe 60 from one flat surface of the thermocouple mounting member 62, and a screw hole is formed on the inner surface of the through hole to form a screw hole 64.

Screw hole 64 formed in thermocouple mounting member 62
Each of the thermocouples 68 is hermetically attached by a compression fitting 66 so that the tip of the thermocouple 68 projects into the measuring pipe 60. Here, a mounting screw portion 70 is screwed and fixed in a screw hole 64 formed in the thermocouple mounting member 62, and a stainless steel tube-shaped fitting ferrule 72 is provided around the thermocouple sheath.
And the holding screw 74 is screwed into the mounting screw 70. The holding screw portion 74 is formed with a through hole for inserting a thermocouple sheath at the center, and the thermocouple sheath is inserted so that its tip has a predetermined protruding length in the measurement pipe, and When the holding screw 74 is screwed into the mounting screw 70 and tightened, the fitting ferrule 72 located inside is compressed and deformed by the mounting screw 70, the holding screw 74 and the thermocouple sheath, and the thermocouple sheath is hermetically sealed. Can be held.

When the thermocouple is fixed by the compression fitting 66, the fitting ferrule (sealant) 72 bites into the sheath of the thermocouple 68. Thermocouple 6
Since the fitting ferrule 72 remains even after the connection pipe 8 is pulled out, the length from the tip of the thermocouple 68 to the fitting ferrule 72 is measured, so that the measuring pipe 6 can be measured.
You can know how many millimeters are within 0.

The actual production procedure is as follows.
A cylindrical thermocouple mounting portion 62 having a parallel flat surface formed on the outer periphery at a predetermined position (temperature measurement position) is welded. The thermocouple mounting portions 62 and the measuring pipe 60 are simultaneously drilled and threaded. At this time, since the processing is performed on a parallel flat surface, the work can be easily performed. Then, the thermocouple 68 is fixed by the compression fitting 66.

In one embodiment, a single measuring pipe (for example, 9 mm in diameter,
There is a configuration in which a total length of 4 m) is used, and a large number of thermocouple mounting members are dispersedly installed therein. Although each thermocouple mounting member may be arranged at equal intervals, the solidification of the molten sample flowing inside is predicted, and the thermocouple mounting members are arranged closer to the position near the solidification expected position in front of the flow. Is good.

FIG. 2 shows another embodiment of the channel for measuring the melt flow velocity according to the present invention. In this example, the measurement channel is modularized, and a plurality of the measurement channel modules 80 are air-tightly connected in tandem using a tube joint (pipe joint) 82 so that a melt flow velocity measurement channel having a required length is formed. Constitute.

Each measurement channel module 80 is basically the same as the measurement channel shown in the above embodiment.
A measuring pipe 60 having a small diameter into which a melt enters, and a plurality of thermocouple attachments each having a cylindrical structure having a parallel flat surface on an outer peripheral portion and fixed at each thermocouple attaching position on the outer periphery of the measuring pipe. A member 62 and a plurality of thermocouples (not shown) are provided. The measurement pipe 60 may be relatively short because a plurality of the measurement pipes 60 cover the entire length of the test section. For example, the length is set to about 1 m for easy handling. A through-hole is formed from one flat surface of the thermocouple mounting member 62 to penetrate the thermocouple mounting portion and the measurement pipe, and the inner surface of the through-hole is subjected to screw processing, and the screw hole 64 is used to perform compression fitting. Each thermocouple sheath is hermetically attached. Since the mounting structure of the thermocouple may be the same as that shown in FIG. 1B, it is not shown in FIG. 2 to simplify the drawing.

The measurement channel module 80 is standardized into a plurality of types having different thermocouple mounting intervals, and the standardized measurement channel module and the measurement pipe module without thermocouple are combined and used as a single unit. Is good.

FIG. 3 shows an example of manufacturing a measurement channel using a measurement channel module. Here, the length of each measurement channel module is set to 1 m, and a test section (total length 4 m) is configured by connecting a total of four channels. The prepared measurement channel module includes a first measurement channel module 91 having a large thermocouple mounting interval,
The second measurement channel module 92 whose thermocouple mounting interval is slightly narrower than that, and the third thermocouple mounting interval that is further narrower
And a measurement pipe module 94 having no thermocouple mounting portion. Considering the time interval of data recording of the melt flow test, determine the minimum interval based on the maximum flow rate predicted from the test conditions, and the maximum interval based on the minimum penetration distance, and A channel module for measurement was designed.

FIG. 3A shows an example in which two first measurement channel modules 91, third measurement channel modules 93, and measurement pipe modules 94 are connected in order from the bottom. FIG. 3B shows, in order from the bottom, a first measurement channel module 91, a third measurement channel module 93, and two measurement pipe modules 94.
Are connected. 3C shows two first measurement channel modules 91 and two second measurement channel modules 91 in order from the bottom.
This is an example in which the measurement channel module 92 is connected. By appropriately selecting and connecting measurement channel modules according to conditions and the like, it is possible to easily and quickly configure an optimal measurement channel for a test.

[0024]

As described above, according to the present invention, the thermocouple mounting member is mounted on the outer periphery of the measuring pipe, and the thermocouple is mounted by compression fitting using the thermocouple mounting member. Excellent effects can be obtained. In order to hold the thermocouple with a thick tubular thermocouple mounting member,
The reliability of the support is significantly improved, and the uncertainty of the position due to thermocouple instability is eliminated, and the reliability of the measured value is improved. The mechanical strength of the measurement channel is increased, and the handling is easy. Drilling can be performed on the side of the thin measuring pipe with a strong block-shaped thermocouple mounting member, so that workability is extremely good. The thermocouple mounting depth can be checked at the fitting ferrule position in the compression fitting. Since the thermocouple is held by the thermocouple mounting member by compression fitting, the mechanical support of the thermocouple is strong, and the airtightness of the mounting portion can be easily ensured.

The present invention also provides the following excellent effects by standardizing and interconnecting measurement channels as a plurality of types of measurement channel modules having relatively short lengths and different thermocouple mounting intervals. Is obtained. By changing the combination of the measurement channel modules, the degree of freedom of the test apparatus that can cope with arbitrary test conditions increases. Since the thermocouple can be easily attached and detached, the use of a stopper can also cope with a thermocouple mounting interval other than the standardized measurement channel module, thereby increasing the degree of freedom in preparing the measurement channel. As a result, the time required for the entire test preparation is sufficiently short, and the necessary test preparation is completed in less than half a day.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a channel for measuring a melt flow velocity according to the present invention.

FIG. 2 is an explanatory view showing a measurement channel connection structure of another embodiment of a melt flow velocity measurement channel according to the present invention.

FIG. 3 is an explanatory view showing a configuration example of a melt flow velocity measurement channel according to the present invention.

FIG. 4 is an explanatory diagram showing a schematic configuration of a melt flow velocity test device.

FIG. 5 is an explanatory diagram showing an example of a conventional technique.

[Explanation of symbols]

 Reference Signs List 60 Measurement pipe 62 Thermocouple mounting member 64 Screw hole 66 Compression fitting 68 Thermocouple 70 Mounting screw part 72 Fitting ferrule 74 Holding screw part

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01P 5/10 G01F 1/68

Claims (4)

(57) [Claims] 1. A measuring pipe having a small diameter and a long length into which a melt enters, and a cylindrical structure having a parallel flat surface on an outer peripheral portion, and are fixed to respective thermocouple mounting positions on the outer circumference of the measuring pipe. A plurality of thermocouple mounting members, and a plurality of thermocouples, and a through hole passing through the thermocouple mounting portion and the measurement pipe is formed from one flat surface of the thermocouple mounting portion, and an inner surface of the through hole is formed. A channel for measuring a flow velocity of a melt, wherein each thermocouple sheath is hermetically attached by compression fitting using a threaded hole and a compression hole. 2. A plurality of measurement pipes having a small diameter into which a melt enters and a cylindrical structure having a parallel flat surface on an outer peripheral portion, the plurality of pipes being fixed to respective thermocouple mounting positions on the outer circumference of the measurement pipe. A thermocouple mounting member, and a plurality of thermocouples, a through hole is formed from one flat surface of the thermocouple mounting portion to penetrate the thermocouple mounting portion and the measurement pipe, and a thread is formed on the inner surface of the through hole. The thermocouple sheath is hermetically attached by compression fitting using the screw holes to form a measurement channel module, and a plurality of the measurement channel modules are hermetically connected in tandem by a tube joint. Melt flow velocity measurement channel. 3. The measurement channel module is standardized into a plurality of types having different thermocouple mounting intervals, and the standardized measurement channel module and a measurement pipe without a thermocouple are combined and used as a single unit. Item 4. The channel for measuring a melt flow velocity according to Item 2. 4. A compression fitting includes a mounting screw portion screwed into a screw hole of a thermocouple mounting member, a holding screw portion through which a thermocouple sheath penetrates the center and tightened to the mounting screw portion, and a thermocouple sheath. 3. The channel for measuring a flow velocity of a melt according to claim 1, comprising a fitting ferrule which is located on the outer periphery and is compressed and deformed by the mounting screw part, the holding screw part and the thermocouple sheath to maintain an airtight state.