Ampoule device for in-reactor analysis

FIELD: power engineering.

SUBSTANCE: device comprises shell with sealing end covers to house at least one capsule with analysed specimens fitted in unsealed thin-wall shell of refractory material. Said capsule is connected with gas lines intended for streaming ventilation of capsule working space. Outlet of every line is plugged for capsule sealing, plugs being composed of sleeves with axial holes filled with fusible material. One of the lines houses thermometer transducers. Note here that sensor of every transducer is fitted inside capsule working space.

EFFECT: measurement of temperatures of emissions at nuclear disintegration during experiments, simplified design of capsule seals.

4 cl, 1 dwg

 

The invention relates to nuclear technology, and more particularly to a sealed irradiation devices for reactor studies of the properties of the fuel elements (Fe).

Known experimental ampoule device designed for use in reactor technology when conducting in-reactor testing of structural and fissionable materials and products from them [Gudkov L.V., goldcrests A.V. Experimental ampoule device, RF patent for the invention №2027233, IPC6G12C 17/06, publ. 20.01.1995]. Known experimental ampoule device consists of a sealed enclosure, inside of which is a capsule with samples. The gap between the capsule and the housing is filled with fusible metal alloy. In the upper part of the body is a cavity with a gas, and the internal volume of the housing is connected with otakuminopera capacity. Between the internal volume and a vacuum cavity installed frangible tube.

In the upper part of the body is a cavity with water vapor, which is designed to simulate an emergency at a nuclear reactor in case of sudden loss of coolant in the core.

Upon reaching the desired burn-in samples to signal the operator collapses the tube and the metal melt flows in otakuminopera capacity. The gap between building the som and the capsule is filled with gas. When this radial thermal resistance of the device increases by 2-3 orders of magnitude.

This could result in filling the gap between the capsule and the body of water, which is typical for emergency.

It is also known a device for irradiation of materials in a nuclear reactor [see Seredkin ST. USSR author's certificate No. 1422883, IPC7G12C 17/06, publ. 20.11.2002].

The device has an outer housing and an ampoule with the sample separated from the outer casing of the gas gap. A device for irradiation of materials in a nuclear reactor designed to increase the performance of the experiment while maintaining the automatic temperature control of the samples. To address this goal cylindrical outer casing is connected to the ampoule by a ring of bumps made of bimetal, and the outer body has a longitudinal corrugations. The disadvantage of this device is that the outer housing can be located only one ampoule that is not possible in a single experiment to irradiate several different fuel element materials in the same conditions.

Closest to the claimed technical solution to the problem at hand and the technical result is a sealed device for reactor research; cited in Wassilewskija "Methods and means of experimental IP the studies and reactor testing thermal emission electricity generating Assembly. M.: Energoatomizdat, 2000, s.112. This technical solution according to the number of matching essential attributes selected as a prototype.

Known ampoule device is intended for studying of free swelling and joint sweling system fuel-shell and consists of a high temperature capsule cylindrical shape, within which is placed the sample, covered with a refractory metal. The capsule is equipped with a gas line for filling with inert gases. At the exit of the highway pneumatic valves for sealing the capsules. The capsule is placed in a stainless steel shell with a radial gap filled with inert gas with different conductivity.

Capsule sealed device with sensors neutron flux and temperature. Ampoule device can irradiate the samples with heat dissipation 60÷240 W/cm3and temperature on shell samples 1600-2200 K. Ampoule device is instrumented and allows you to adjust the irradiation parameters in the tests.

However, this solution has several disadvantages:

- does not allow to analyze in the course of the experiment gaseous fission products (GPA)released during nuclear decay;

- not possible to measure the temperature of the sample during the experiment;

- sealing work is her oral ampoule device is pneumatic valves, what complicates the design and technology of manufacture of the device, in addition, the process of depressurization occurs under the influence of high pressure on the operating element of the valve, which implies the presence in the test bench of additional equipment, such as gas high-pressure line.

Task to be solved by the present invention is directed, is the creation of a sealed device for reactor research, allowing to measure the temperature of the samples during the experiment, analysis GPA released during nuclear decay during the experiment, to have a simple design and technological point of view, the mechanisms of the temporary sealing of the working cavity.

The task and the technical result is achieved by the fact that the ampoule device for reactor research, including a shell with a sealing end caps, inside which there is at least one capsule, with the test sample placed in non-vacuum thin-walled shell of refractory material according to the invention the capsule is supplied in addition to a gas line additional line with the possibility of flow-through ventilation of the working cavity of the capsule, at the output of each line set stubs for temporary hermeti the emission capsules, made in the form of a bushing with an axial hole filled with fusible material, thermometric sensors enclosed in sealed covers, are located in one of the highways, with the sensing element of each sensor is introduced into the working cavity of the capsule.

Tight connection of the capsule shell ampoule device can be realized by means of the bellows is placed in one of the highways.

In the private embodiment, the sleeve is located in line with thermometric sensors can be provided for axial holes for placing covers thermometric sensors, sealed with the sleeve by means of soldered connections.

Ampoule device may be further provided with a heat radiator installed inside with a gap coaxial shell ampoule device, the heat sink is made of axial holes located around the circumference at the same axial distance from the end face of the radiator to install the capsules with the test samples.

Introduction the ampoule device additional line allows you to analyze the experiment gaseous fission products (GPA)released during nuclear decay, due to the flow-through ventilation of the working cavity of the capsule, which provides t is unsportive GPA to analyzing the bench reactor.

The location of sensitive elements thermometric sensors in the working cavity of the capsule allows you to measure in the experiment, the temperature of the sample.

The design of the plugs for temporary sealing of the working cavity of the capsule in the form of a bushing with an axial hole filled with fusible material, simplifies the manufacturing technology of the plugs. In addition, this design simplifies the process of depressurization of the working cavity of the capsule, without the need to create in the arteries high blood pressure.

The presence in the design ampoule device heat sink, in the axial holes which are installed capsules at the same axial distance from the end face of the heat sink (respectively at the same level of the reactor core), simultaneously in the same conditions to test multiple samples in offline capsules.

The essence of the claimed invention is illustrated by the drawing, which schematically depicts the design of the ampoule device.

Ampoule device consists of a cylindrical shell (1) with two end sealing caps (2, 3), a cylindrical heat sink (4)that is installed inside the shell (1) coaxial with the last gap for optimal heat dissipation. In the axial hole at back is the second radiator (4), made on the same axial distance from the end face of the radiator, are the capsules (5) stainless steel. Each capsule includes the investigated fuel sample (6), enclosed in a thin-walled shell (7) of the refractory material. Each capsule is hermetically coupled to gas pipelines (8, 9) and shell (1) ampoule device with bellows (10)installed in one of the gas lines. At the exit of the gas lines installed caps (11, 12)made in the form of sleeves (13, 14). The sleeve (13) has an axial hole (15, 16) for installation of temperature sensors and a hole (17) for passage of gases. The sleeve (14) is also provided with a hole (18) for passage of gases. Holes (17, 18) filled with solder of the fusible material. Sealed pouches (19, 20) sensors mounted in the axial hole (15, 16) and is hermetically coupled to the sleeve (13)and the sensor elements (21) sensors introduced into the working cavity (22) of the capsule (5). In addition, in the capsule provided by Belleville springs (23), spacer (24), guide sleeve (25).

The drawing shows a variant of the ampoule device with three capsules mounted in the axial holes of the heat sink, which is made on the same axial distance from the end face of the radiator, which gives the opportunity to test samples under the same flux is Oh neutrons in the reactor. However, the capsules may be a different number.

The proposed ampoule device is as follows. Ampoule device, which consists of one or more capsules with a test sample rods, attached to the gas communications reactor. When this advance is the inert gas filling the working cavity of the capsules, which are analyzed samples of the fuel rods, the temporary sealing it with fusible material of the plugs. The sensitive elements of sensors located in a hermetically introduced into the cavity of the samples covers, wind up in the gas line capsules. Connection ampoule device with a gas communications reactor is carried out by welding. After gas pipeline ampoule device will be sealed, is the destruction of the fusible material of the plugs due to the heating of location and create a pressure difference in the right direction. Next, the entire Assembly is installed in the cell of the reactor.

When the output of a nominal mode, the sample (6) is in contact with the thin-walled shell (7) due to thermal expansion. Thin-walled shell pattern allows it to expand freely. To compensate for axial expansion of the sample provided by arelative spring (23). However, the thin-walled shell (7) and the shell of the capsule (5) there remains a gap for passage of gases.

The system allows you to adjust the conditions of heat transfer from the surface of the fuel rods to the coolant (water) through changes in the composition of the gas in the gap between the thin-walled shell (7) and the shell of the capsule (5).

An example of a specific implementation.

The design ampoule device for testing fuel samples UN in the reactor TRS-2M.

Ampoule device comprises a shell made of stainless steel with a thickness of 1 mm and a diameter of 54 mm, two end caps with holes for gas lines, cylindrical aluminum radiator made it three axial holes, which are capsules. Each capsule has a shell made of stainless steel with a thickness of 1 mm, which with a gap of 200 μm is placed investigated the fuel sample in a thin-walled shell, two end caps with tightly attached gas pipelines of stainless steel. Fuel sample with a diameter of 8 mm and a length of 35 mm mounted in thin-walled shell of a single crystal of tungsten with a thickness of 0.3 mm with a gap of 30 μm. One of the sensors is introduced in the fuel sample. The second sensor is located outside of the sample, in contact with the casing through a spacer made of molybdenum and is used to control the temperature of thin-walled shell of the investigated sample. In each gas line installed sleeve with an axial hole with a diameter of 22 mm, filled with fusible solder POS for temporary sealing of the capsule. And one of the sleeves has two additional holes of 2 mm diameter, which are soldered covers sensors, made of molybdenum. Shell capsules connected with the shell ampoule device through the bellows of stainless steel. To compensate for axial expansion of the investigated fuel sample introduced Belleville springs alloy BP-27.

The design of the ampoule device allows complete Assembly in the absence of contact of the sample with oxygen.

The system enables the transport of gaseous fission products to analyze the stand of the reactor through the implementation of flow-through ventilation of the working cavity of the capsule through the gas pipeline. This gives the opportunity to analyze released in the course of the experiment GPA.

Ampoule device simultaneously under identical conditions to test multiple samples in offline capsules located in the heat sink on the same axial distance from the end face of the heat sink, respectively - at the same level of the reactor core.

After finishing the test when conducting post-irradiation studies of capsules direct Redstone measurement of the geometry of the samples will allow us to estimate the change in the size of the specific irradiation conditions.

1. Ampoule device for reactor research, including a shell with a sealing end caps, inside which there is at least one capsule with a test sample placed in non-vacuum thin-walled shell of refractory material, while the capsule is equipped with thermometric sensors enclosed in sealed covers, and is connected with a gas line, wherein the capsule is provided with an additional gas line with the possibility of flow-through ventilation of the working cavity of the capsule, at the output of each line set stubs for temporary sealing of the capsule is made in the form of a bushing with an axial hole filled with fusible material, thermometric sensors are located in one of the highways, while the sensing element of each sensor is introduced into the working cavity of the capsule.

2. Ampoule device according to claim 1, characterized in that the capsule is hermetically coupled to the ampoule shell device with bellows placed in one of the highways.

3. Ampoule device according to claim 1, characterized in that the sleeve is located in line with thermometric sensors, equipped with an additional axial holes for placing covers thermometric sensors, sealed with the sleeve by means of solder is soedineniya.

4. Ampoule device according to claim 1, characterized in that it further provided with a heat radiator installed inside with a gap coaxial shell ampoule device, the heat sink is made of axial holes located around the circumference at the same axial distance from the end face of the radiator to install the capsules with the test samples.



 

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