Note: Descriptions are shown in the official language in which they were submitted.
CA 02610419 2012-02-09
PLUG TYPE RESEARCH REACTOR IRRADIATION TEST RIG
1. Field of the Invention
The present invention relates to an irradiation test
rig loaded in a research reactor and a test assembly for
fixing the specimen capsule, more specifically to an art
optimized so as to improve the integrity and safety of the
reactor core by minimizing the effect of the irradiation
test rig on the whole of the reactor core due to fluid-
induced vibration, etc. of the reactor core coolant in the
irradiation hole of the research reactor, especially to a
plug type research reactor irradiation test rig which
implements an art by which the specimen capsule inserted
into the rig is easily installed or uninstalled in/from the
test assembly so that the rig and test assembly can be
reused and the continuity of test can be secured.
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2. Description of the Related Art
In general, irradiation tests using a research reactor
include a nuclear fuel irradiation test using fissile
material, an irradiation test of materials related to
nuclear power and an irradiation test of the industrially
used materials for semiconductor or medical use. Rigs used
in such research reactor irradiation tests can be divided
into uninstrumental rigs, instrumental rigs and rigs used in
cyclic loops, etc.
Of them, the nuclear fuel irradiation test rigs for use
in a research reactor are classified into instrumental rigs
that trace irradiation history during test (for example,
reactor core data such as neutron flux, coolant temperature,
flow rate and flow velocity) or measure in real time the
characteristic data (for example, cladding temperature and
pellet internal temperature, test fuel rod internal pressure,
cladding irradiation growth and deformation, etc.), and
uninstrumental rigs that do not.
With rapid progress of nuclear power technology,
utilization of a research reactor is increasing in
commercial use as well as for research purposes. Especially,
as the development of nuclear fuel and related materials
used in nuclear power plant is utilized to provide important
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r t
data for economic benefits such as prolongation of the life
of nuclear reactor and securing safety, the demand for
irradiation tests using a research reactor is increasing.
Furthermore, as irradiation tests are expanding as a result
of the utilization and development of the next-generation
nuclear energy, various irradiation tests using a research
reactor have become indispensable.
For the rigs used in such irradiation tests, thermal-
hydraulic compatibility of the research reactor core and
proof of integrity for the structure of reactor core
irradiation holes are essential. The reliability of the
irradiation test results cannot be secured unless the
compatibility between the fluid-induced irradiation test rig
and the reactor core structure and the structural integrity
are confirmed before irradiation test. The research reactor
core should not have mechanical damage due to fluid-induced
vibration generated in the inner wall of the irradiation
hole, and resistance against wear of the rig itself due to
long-term irradiation testing must be secured to ensure
structural integrity and reliability. Also, it should have a
structure in which it is easy to assemble and disassemble
the specimen capsule in the disassembly of the rig and in
the test assembly through manipulator operation in the hot
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cell as necessary.
In the research reactor in the prior art, the reactor
core structure should have the selection of its side wall
material and the choice of its structure made very carefully
to maximize the utilization of neutrons. So, the side wall
of the central portion of the research reactor core is made
of neutron reflector instead of neutron absorber or the
selected material that is less deformed by neutrons, and it
is preferable that it has a structure of a thin a form as
possible while not obstructing the utilization of neutrons.
In the case of the research reactor, the central
portion of the reactor core uses a flow pipe to load nuclear
fuel or use a test rig, but the irradiation hole on the
outer wall of the reactor core has a relatively thin side
wall. Moreover, the inside of the reactor core cask is
filled with moderator, so leakage of moderator due to damage
to the reactor core cask leads to a serious safety accident.
Therefore, the research reactor operator tends to avoid
direct contact therewith because the upper spring of the
existing irradiation test rig is always abraded by fluid-
induced vibration causing friction with the side wall of the
irradiation hole, and to solve this problem, a using the
guide tube.
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Another problem is that although the generally used
method to loading a specimen in the irradiation test rig is
fixing by welding in the direction of the shaft, it is in
such a structure that the fixed portion of the sample has to
be cut during disassembly. This is one of the factors that
make the repeated use of the irradiation test rig difficult.
As an example of an uninstrumental rig for nuclear fuel
irradiation test according to the prior art, the
uninstrumental rig disclosed in the Korean Patent
Registration No. 10-0435226, "Non-instrument Rig for Nuclear
Fuel Irradiation Test Using the Irradiation Hole of the
Research Reactor" has its structural integrity secured even
after the 3-year term of durability has expired, and various
irradiation tests were conducted through vertical
arrangement of different nuclear fuel test rods.
Also, there is an example of successfully carrying out
disassembly of an non-instrumental rig for irradiation test
and assembly of a new rig through remote operation in the
hot cell by using the "Remote Rig Assembly Apparatus for
Nuclear Fuel Irradiation Test." disclosed in the Korean
Patent Registration No. 10-0369248.
But as a result of visual inspection and performance
testing for the irradiation test rig with its durability
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term expired, the integrity that enables repeated use is
secured and it is possible to reduce the radioactive waste
through recycle of the rig. In addition, since the test fuel
rod, which is the specimen capsule, is fixed in an assembly
form, it cannot be effective unless the test assembly is
reused as well in order to recycling the rig. Therefore, a
structural change is necessary from the existing fixed-type
structure by welding the test fuel rod to the built-up type.
SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to
provide an irradiation test rig, which prevents the
irradiation test rig from directly contacting the
irradiation test hole wall formed on the weak side such as
the irradiation hole side wall of the research reactor, and
which is mounted and fixed in a plug type fashion on the
top-end core plate and the lower end spider cup, so that the
irradiation hole wall of research reactor is protected to
secure the reactor core integrity and the improved safety.
Another object of the present invention is to provide
an art by which the specimen capsule can be charged on the
side of the test assembly in the case of the existing form
of the combined assembly, that is, an art of irradiation
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test rig, by which it is possible to reuse the irradiation
test rig and reuse the test assembly inserted with the
specimen capsule, so that an incidental effect of reducing
radioactive waste can be obtained; and since it is easy to
assemble and disassemble, it is possible to test by loading
the specimen capsules that require different test periods in
the same rig; and various tests are possible such as
monitoring the change through intermediate checking of
specimen capsules by taking out the rig from the research
reactor.
In accordance with the present invention, there is
provided a plug type research reactor irradiation test rig
comprising: an upper fixed body, at least one test assembly,
and a lower fixed body which are assembled in sequence from
top to bottom, wherein the rod tip of the lower fixed body
is installed on a spider cup formed in the lower end portion
of the irradiation hole of the research reactor core, and
the top-end plate of the research reactor core is pressed by
the upper fixed body when it is installed.
Preferably, the upper fixed body comprises a hollow
fixed body; a grapple head which is located inside the fixed
body and is provided with an upper flow path plate installed
on the top end side of the fixed body and a lower flow path
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plate installed on bottom of the fixed body; and a spring
arranged below the lower flow path plate.
Preferably, the fixed body comprises a plurality of
through holes formed on the circumference for cooling fluid
to flow, a fixed flange which is formed monolithically with
the upper end of the fixed body to be in contact with the
top-end plate of the research reactor core, and a plurality
of slits which are extended to a predetermined length
downward lengthwise of the fixed body from the fixed flange.
Preferably, the grapple head is provide with a top-end
slit formed in the upper end portion thereof for rotating
the grapple head and a support portion formed at the lower
end portion thereof for connecting to the top-end plate of
the rig and maintaining the directionality of cooling fluid
flow.
Preferably, wherein the upper flow path plate and the
lower flow path plate are provided respectively with flow
holes formed so as to induce pressure drop and flow of
cooling fluid and outer circumferences that are designed for
smooth up-and-down motion of the fixed body, the upper flow
path plate includes chamber which is formed for smooth flow
of cooling fluid and an insert hole which is formed in the
central portion to be in close contact with the body of the
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grapple head, and the fixed flange of the fixed body is
prevented from breaking away inward by a rib structure
defining the chamber, and the lower flow path plate includes
a spring seat formed so as to mount a spring at the bottom
end of the fixed body and a rib portion formed so as to be
in contact with the top-end plate of the rig.
Preferably, the test assembly comprises an upper
housing connected to the upper fixed body or another test
assembly; a lower housing connected to the lower fixed body
or another test assembly; a cooling block which is arranged
above the lower housing and is for cooling the cooling
fluid; a plurality of supports monolithically formed with
the cooling block to support the upper housing; and at least
one specimen capsule in which the sample is inserted.
Preferably, the upper housing comprises an upper plug
holder in which the upper plug of the specimen capsule is
slidably installed, an upper arc portion in which the upper
plug is installed in sliding contact, an upper center hole
in which the upper end of a central axis of the cooling
block is fixed, upper flow path chambers in which the
cooling fluid flows, upper fixing holes in which the upper
end of the supports are fixed, an upper rib which defines
the upper center hole and the upper flow path chambers, and
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guide slots which are formed above the cylindrical surface
of the lower housing to fix the rotation and position
between support tubes, and the lower housing comprises a
lower plug holder in which the lower plug of the specimen
capsule is slidably installed, a lower arc portion in which
the lower plug is earthed to be installed, a lower center
hole in which the lower end of the central axis of the
cooling block is fixed, lower flow path chambers in which
the cooling fluid flows, lower fixing holes in which the
lower end of the supports are fixed, a lower rib which
defines the lower center hole and the lower flow path
chambers, and guide slots which are formed below the
cylindrical surface of the lower housing to fix the rotation
and position between support tubes.
Preferably, the specimen capsule(test rod) comprises a
tube into which the sample to be tested is inserted and an
upper plug and a lower plug which are monolithically
installed respectively at the upper end and the bottom end
of the tube.
Preferably, the upper plug and the lower plug have
insertion ends formed monolithically with a diameter roughly
the same as the inner diameter of the tube, and flat
surfaces with a size roughly the same as the upper and lower
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plug holders of the upper and lower housing, and arc
surfaces which can earth the upper arc portions are formed
halfway between the enlarged diameter portions of the upper
plug and the lower plug, and a slit is formed in the
enlarged diameter portion of the upper plug.
Preferably, the specimen capsule(test rod) comprises an
outer tube, an upper annular plug and a lower annular plug
which are inserted in the upper and lower ends of the outer
tube, and an inner tube arranged inside of the outer tube,
and wherein halfway between the enlarged diameter portions
of the upper annular plug and lower annular plug are formed
flat surfaces with a size roughly the same as the upper
annular plug holders of the upper and lower housing and arc
surfaces which can earth the upper arc portions, and a slit
is formed in the enlarged diameter portion of the upper plug,
and flow holes communicated with the inner tube for inner
cooling are formed in the upper annular plug and lower
annular plug.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features, aspects, and
advantages of preferred embodiments of the present invention
will be more fully described in the following detailed
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description, taken in conjunction with the accompanying
drawings. In the drawings:
Fig. 1 is a front view showing a plug type research
reactor irradiation test rig according to an embodiment of
the present invention;
Fig. 2 is a schematic side view showing an irradiation
hole of the research reactor fitted with the plug type
research reactor irradiation test rig of Fig. 1;
Fig. 3 is a solid view and a perspective view showing
an upper fixed body of the plug type research reactor
irradiation test rig of Fig. 1;
Figs. 4A to 4E are perspective views showing the
components of the upper fixed body illustrated in Fig. 3;
Fig. 5 is a perspective view showing the state in which
the specimen capsules(test rods) are assembled into the test
assembly of the plug type research reactor irradiation test
rig illustrated in Fig. 1;
Fig. 6A is a perspective view showing the state in
which the specimen capsules(test rods) are removed from the
test assembly illustrated in Fig. 5;
Figs. 6B to 6D are perspective views of the components
of the test assembly illustrated in Fig. 5;
Figs. 7A to 7C are perspective views showing a first
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4
example of the specimen capsule(test rod) of the solid type
illustrated in Fig. 5 and components thereof; and
Figs. 8A to 8C are perspective views showing a second
example of the specimen capsule(test rod) of the annular
type illustrated in Fig. 5 and components thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Hereinafter, the preferred embodiments of the present
invention will be described with reference to the
accompanying drawings.
Fig. 1 is a front view of a plug type research reactor
irradiation test rig according to an embodiment of the
present invention, an assembly drawing in which an upper
fixed body 1, at least one test assembly 2, and a lower
fixed body 3 are assembled in sequence from top to bottom.
As shown in Fig. 2, the plug type research reactor
irradiation test rig is mounted inside a research reactor
core 100. The rod tip of the lower fixed body 3 is fastened
to a spider cup 200 formed in the bottom end portion of the
irradiation hole of the research reactor core 100.
Also, the top-end plate of the research reactor core
100 is pressed by the upper fixed body 1 when a plug type
research reactor irradiation test rig is mounted.
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4
Accordingly, it is possible to prevent the irradiation test
rig from directly contacting the weakly side wall of the
irradiation test hole such as the irradiation hole side wall
of the reactor.
As shown in Fig. 3, the upper fixed body 1 comprises a
fixed body 10, a grapple head 11 arranged inside the fixed
body 10, and a spring 14 arranged on the bottom of the fixed
body 10. And, the grapple head 11 further comprises an upper
flow path plate 12 and a lower flow path plate 13, which are
welded in predetermined positions respectively. The grapple
head 11 plays a role of fixing the whole of the rig.
In an embodiment of the present invention, as shown in
Fig. 4A, the upper flow path plate 12 is installed in
contact with the topside of a fixed flange 101 of the fixed
body 10, and the lower flow path plate 13 is installed above
the spring 14 arranged on the bottom of the fixed body 10.
The fixed body 10 is formed in a hollow pipe body, and the
fixed flange 101 to be in contact with the top-end plate of
the research reactor core is formed monolithically with the
upper end portion of the fixed body 10.
Downward from the fixed flange 101 is formed a slit 102
having a predetermined length lengthwise along the fixed
body 10. In this embodiment of the present invention is
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illustrated a structure with 3 slits formed therein. In the
lower end of the slit 102 is monolithically formed a break
preventing hole 103 with a size expanded more than the
cleavage of the slit 102 to prevent stress concentration.
Accordingly, by means of the slit 102, flexibility can be
secured when the plug type research reactor irradiation test
rig is inserted into the irradiation hole of the research
reactor core 100.
In addition, the portion where the slit 102 is formed
is formed in a tapered portion in which the cross section
increases as it goes upward, so that fastenability can be
improved when the plug type research reactor irradiation
test rig is inserted in the irradiation hole of the research
reactor core 100.
And, in the middle portion of the fixed body 10 below
the slit 102 are formed through holes 104 for inducing the
cooling fluid to flow inward. In this embodiment of the
present invention, through holes 104 are arranged
circumferentially and lengthwise on the circumference of the
fixed body 10 to make a grid shape.
As shown in Fig. 4B, the spring 14 is of a coil shape,
and it plays a role of pulling the upper fixed body 1 down
by compression force of itself when the upper fixed body 1
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of the present invention is installed in the irradiation
hole.
The grapple head 11, as shown in Fig. 4C, has a top-end
slit 111 formed at the top end thereof to help rotational
charging by connection with a tool for installing, and in
the upper portion and lower portion of the body of the
grapple head 11 are fixed the upper flow path plate 12 and
the lower flow path plate 13, respectively. The upper flow
path plate 12 prevents the fixed body 10 from breaking away
inward, and the lower flow path plate 13 plays a role as a
spring seat on which the upper end of the spring 14 that
helps the upper fixed body 1 to be pressed downward is fixed
and supported. As described in detail below, the upper flow
path plate 12 and the lower flow path plate 13 include flow
holes 122 and 134 respectively for inducing pressure drop
and fluid flow suited for testing. In order to maintain the
directionality of such fluid flow, a support portion 114
connected to the top-end plate of the rig is monolithically
formed at the lower end portion of the grapple head 11.
The upper flow path plate 12, as shown in Fig. 4D, has
an outer circumference 121 formed for smooth up-and-down
motion of the fixed body 10, and the inside of the outer
circumference 121 is provided with the flow holes 122 for
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inducing smooth flow of cooling fluid and a chamfer 123 at
the bottom end. By means of the rib structure defining the
flow holes 122 and the chamfer 123, the fixed flange 101 of
the fixed body 10 is prevented from breaking away inward.
And, in the central portion of the upper flow path plate 12
is formed an insert hole 124 that is inserted the body of
the grapple head 11 in close contact therewith.
In the lower flow path plate 13, as shown in Fig. 4E,
is formed a spring seat 133 for mounting the upper end of
the spring 14 that is arranged on the bottom of the fixed
body 10, and on the outside is formed the outer
circumference 131 for smooth up-and-down motion of the fixed
body 10. And, the lower flow path plate 13 is provided with
a rib portion 132 that is in contact with the top-end plate
of the rig. This rib portion 132 defines the flow holes 134
for inducing smooth flow of the cooling fluid.
Fig. 5 is a perspective view showing the state in which
the specimen capsules 24 are assembled into the test
assembly 2 of the plug type research reactor irradiation
test rig illustrated in Fig. 1. The test assembly 2
comprises an upper housing 20 connected to the upper fixed
body 1 or another test assembly 2, a lower housing 21
connected to the lower fixed body 3 or another test assembly
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2, a cooling block 22 for cooling the cooling fluid, a
plurality of supports 23 which are monolithically formed
with the cooling block 22 to support the upper housing 20,
and at least one specimen capsule 24 in which the sample is
inserted.
Fig. 6A is a perspective view showing the state in
which the specimen capsules 24 are removed from the test
assembly 2 illustrated in Fig. 5, and Figs. 6B to 6D are
perspective views of the upper housing 20, the lower housing
21, and the cooling block 24 of the test assembly
illustrated in Fig. 5, respectively;
As shown in Fig. 6B, the upper housing 20 comprises at
least one upper plug holder 201 in which at least one upper
plug 31 of the specimen capsule 24 is slidably installed,
and at least one upper arc portion 202 in which the upper
plug 31 is inserted to have sliding contact. Accordingly,
the upper plug holder 201 and the upper arc portion 202 clip
together, so that the upper plug 31 of the specimen capsule
24 can be inserted in the upper housing 20 by using the
opening of the upper plug holder 201 during insertion, while
after insertion, the upper arc portion 202 and the upper
plug 31 maintain sliding contact to obstruct the breakaway
of the upper plug 31 by the upper plug holder 201. To
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separate, the upper plug 31 can be removed from the upper
housing 20 through the opening of the upper plug holder 201.
For this purpose, as will be described in detail later with
reference to Fig. 7B and 7C, flat surfaces 312 and arc
surfaces 311 are formed on the outer circumference of the
upper plug 31.
In addition, the upper housing 20 comprises an upper
center hole 205 for the upper end of a central axis 225 (Fig.
6D) of the cooling block 22 to be fixed, upper flow path
chambers 206 for cooling fluid to flow, upper fixing holes
203 for the upper end of the supports 23 to be fixed, and an
upper rib 207 that defines the upper center hole 205 and the
upper flow path chambers 206. And, on the top of the
cylindrical surface of the upper housing 20 are formed guide
slots 204 for rotation between support tubes and fixing of
the position.
As shown in Fig. 6C, the lower housing 21 comprises at
least one lower plug holder 211 in which at least one lower
plug 32 of the specimen capsule 24 is slidably installed,
and at least one lower arc portion 212 in which the lower
plug 32 is inserted to have sliding contact. Accordingly,
the lower plug holder 211 and the lower arc portion 212 clip
together, so that the lower plug 32 of the specimen capsule
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24 can be inserted in the lower housing 21 by using the
opening of the lower plug holder 211 during insertion, while
after insertion, the lower arc portion 212 and the lower
plug 32 maintain sliding contact to obstruct the breakaway
of the lower plug 32 by the lower plug holder 211. To
separate, the lower plug 32 can be removed from the lower
housing 21 through the opening of the lower plug holder 211.
For this purpose, as will be described in detail later with
reference to Fig. 7B and 7C, flat surfaces 322 and arc
surfaces 321 are formed on the outer circumference of the
lower plug 32.
In addition, the lower housing 21 comprises an lower
center hole 215 for the lower end of the central axis 225 of
the cooling block 22 to be fixed, lower flow path chambers
216 for cooling fluid to flow, lower fixing holes 213 for
the lower end of the supports 23 to be fixed, and an lower
rib 217 that defines the lower center hole 215 and the lower
flow path chambers 216. And, on the top of the cylindrical
surface of the lower housing 21 are formed guide slots 214
for rotation between support tubes and fixing of the
position.
The cooling block 22, as shown in Fig. 6D, comprises
cooling flow paths 221 designed for the specimen capsules 24
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to have a predetermined cooling capability, and the cooling
flow paths 221 are affected also by the decision of the
areas of upper and lower flow path chambers 206 and 216 of
the upper and lower housing 20 and 21. The cooling block 22
is provided with cooling holes 222 though which three
supports 23 of the test assembly 2 pass, and the cooling
holes 222 are formed alternately with the cooling flow paths
221.
At the center of the cooling block 22 is located the
central axis 225, and at the upper end and the lower end of
the central axis 225 are formed an insertion end 223 for the
upper housing 20 and the lower housing 21 to be inserted
into the upper center hole 205 and the lower center hole 215
of the upper housing 20 and the lower housing 21
respectively. At the center of the insertion end 223 is
formed a central hole 224 for the central axis (not shown)
of the rig to be inserted.
The specimen capsule 24, as shown in Fig. 7A, comprises
a tube 30 into which the sample to be tested is inserted,
and an upper plug 31 and a lower plug 32 which are inserted
into the upper end and the lower end of the tube 30,
respectively.
As shown in Fig. 7B and 7C, respectively in the upper
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plug 31 and the lower plug 32 are monolithically formed
insertion ends 315 and 325 having outer diameters that are
roughly the same as the inner diameter of the tube 30.
Accordingly, after inserting insertion ends 315 and 325 into
the tube 30 for assembly, the upper plug 31 and the lower
plug 32 are joined monolithically with the tube 30 using the
joining method like welding to complete the specimen capsule
24.
Halfway between the enlarged diameter portions 313, 314
and 323, 324 of the upper plug 31 and the lower plug 32 are
formed flat surfaces 312 and 322 having diameters roughly
the same as the opening of the plug holders 201 and 211 of
the upper and lower housing 20 and 21, and arc surfaces 311
and 321 which have sizes roughly the same as the inner
diameter of the arc portions 202 and 212 and which can earth
these arc portions. Accordingly, during insertion, the upper
and lower plugs 31 and 32 of the specimen capsule 24 can be
inserted in the upper and lower housings 20 and 21
respectively by passing through the opening of the plug
holders 201 and 211 using the flat surfaces 312 and 322,
while after insertion, the arc surfaces 311 and 321 maintain
sliding contact by means of arc portions 202 and 212 and at
the same time obstruct the breakaway of the upper and lower
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plugs 31 and 32 by means of the plug holders 201 and 211.
In the enlarged diameter portion 313 of the upper plug
31 is formed a slit 316, so that the upper plug 31 is
rotated to be inserted in the upper housing 20, and so that
after insertion, the specimen capsule 24 is prevented from
breaking away from the test assembly 2.
Fig. 8A illustrates a specimen capsule 24 of a double
cooling type identical to the one illustrated in the left
drawing of Fig. 5.
The specimen capsule 24 of the double cooling type
comprises an upper plug 41, a lower plug 42, outer tube 40,
and inner tube 44. After putting a sample 43 between the
outer tube 40 and the inner tube 44, the upper plug 41 and
the lower plug 42 are fixed to the upper end and the lower
end of the outer tube 40 respectively.
As shown in Fig. 8B and Fig. 8C, the upper plug 41 and
the lower plug 42 are provided with insertion ends 415 and
425 that fit the inner diameter of a given outer tube 40,
and after the end portions of the insertion ends 415 and 425
are inserted into the outer tube 40 in contact with the
inner tube 44, they are welded to complete the specimen
capsule 24.
And, halfway between the enlarged diameter portions 413,
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414 and 423, 424 of the upper plug 41 and the lower plug 42
are formed flat surfaces 412 and 422 with a size roughly the
same as the plug holders 201 and 211 of the upper housing 20
and lower housing 21 and arc surfaces 411 and 421 that can
earth the arc portions 202 and 212.
In the enlarged diameter portion 413 of the upper plug
41 is formed a slit 416, so that the upper plug 41 is
rotated to be inserted in the upper housing 20 and lower
housing 21, and the specimen capsule 24 is prevented from
breaking away from the test assembly 2 in this condition.
In the upper plug 41 and the lower plug 42 are formed
flow holes 417 and 426 which are communicated with the inner
tube 44 for cooling the inside.
As described above, by the plug type research reactor
irradiation test rig according to the present invention, the
upper fixed body avoids contact with the irradiation hole
side wall that is relatively weak in the research reactor
core and is press-fixed with the top-end plate of the
reactor core in a plug type fashion, so that the integrity
and durability of the reactor core are improved, and by
saving the installation and uninstallation time of the rig
inserted into the irradiation hole, effective operation and
effective irradiation test of the reactor can be conducted.
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In addition, by means of the clip-form shape of the
upper housing and lower housing of the test assembly, the
circular test fuel rod of the specimen capsule is easily
installed and uninstalled on the side of the test assembly,
so that it provides a basic art by which it is possible to
plan and conduct tests of various forms such as adjustment
of test periods and repeated testing of the specimen capsule
as well as position change of the specimen capsule.
Using the conventional irradiation test rig, it was
inevitable to produce large quantities of radioactive waste
from the rig due to one-time use, but by means of the
present invention, it is possible not only to conduct
various tests through reuse of the irradiation test rig and
the test assembly, but also to obtain economic benefits due
to the effect of reduced radioactive waste and the repeated
use.
Although the present invention has been described in
detail reference to its presently preferred embodiment, it
will be understood by those skilled in the art that various
modifications and equivalents can be made without departing
from the spirit and scope of the present invention, as set
forth in the appended claims.
