JPS59695A - Impurity recovering device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] This invention is a foreign matter recovery device, especially for burning used nuclear materials. This invention relates to improvements in equipment for collecting .

Nuclear fuel assemblies that have become used after a certain period of operation are removed from the reactor and placed in a storage pool (so-called 5PE).
The fuel is stored in the nt Fuel Pool, where damage is inspected and damaged areas are repaired, and the fuel is stored for reloading during reactor regular inspections and during the cooling period before being transferred to the reprocessing plant. It is common to leave the

However, during this work, screws, small parts, tools, etc. used for assembling fuel assemblies are often dropped into the pool, and leaving them as they are will result in high quality From a dangerous place such as damaging fuel assemblies under control, we monitor the foreign object M with an underwater television on the bridge above the pool P as shown in Figure 1.
The collecting device A is operated to pick up the foreign matter M with the packet claw h and put it into a bucket E for collection.

By the way, the recovery device 1A is as shown in FIG.
Main cylinder part As (diameter approx. 5CI11% length 7~8rrL
) is connected to this so that it can be expanded and contracted, and has a tip cylinder part A2 with a packet claw A3 attached to the lower end so that it can be opened and closed freely, and an air cylinder member and a coil spring are incorporated in each cylinder part. , this is connected to a compressor, and the compressed air opens and closes the packet claw As or the front cylinder part A2.
It is designed to perform expansion and contraction operations. As a result, not only the internal structure of the local area becomes rough, but also air leakage from the hose connection causes foaming of the pool water, and the foaming causes the pool water to become cloudy. :tt C water-soluble radiation.Also, instead of air cylinder and compressed air, 1! There is also a method using a ventilator, but this has the problem of poor insulation.

This invention has been devised in view of these circumstances, and aims to provide a recovery device that can be safely operated without the risk of polluting the atmosphere or causing electrical leakage, has a simple configuration, and is lightweight. b) At the lower end of the pipe-shaped operation lever of the required length, there is a pipe on the top surface that extends upward during operation and is connected to the water heater, and on the bottom surface there are 4 pipes.
A hollow distributor is fixed with multiple nozzles, and a column with brackets extending from all sides is attached to the bottom of the distributor, and each bracket has a claw plate and an outer fN wall. and a packet claw whose upper end is inclined outward, respectively, and the upper end of the column and the upper end of each packet claw are connected by a first spring made of a shape memory alloy, and the lower end of the column is connected to the upper end of each packet claw. and the central part of the upright rod of each packet pawl are connected by a second spring made of spring steel, and each packet pawl is closed at room temperature to cause the first spring to expand and deform.

FIG. 6 shows an embodiment of the present invention, in which reference numeral 1 denotes an operating rod made of pipe material with a diameter of about 4 csr and a length of 8 to 10 m, and a hollow distributor 2 of the same diameter is attached to the lower end of the operating rod. is fixed by welding or the like, and the vibro installed vertically in the center of the upper surface of the distributor 2 extends upward in the operating rod 1, bends at the upper end, and connects the It is connected to a water heater (not shown) located on the bridge of the storage pool.

On the lower surface of the distributor 2, as shown in the mouth in Fig. 5A, a square holding lip 2α is provided, and a downward nozzle 2b is provided at the center of the outside of the west side of the lip. The upper end of the rectangular column 4 is fitted into the holding rib 2α and screwed to the lower surface of the distributor 2.

As shown in Fig. 6A, the columnar body 4 is provided with an overhanging bracket 4α in the center of the west side for pivotally supporting the packet claw 5, which will be described next, and a spring member at the upper and lower ends. Horizontal groove 4 that opens toward each side for inserting a retaining ring
Four screw holes 4b each having a hole C in the middle for inserting a bolt are drilled therein.

As shown in FIG. 4, the packet claw 5 consists of a flat claw plate 5α forming a quarter circle, an outer peripheral wall 5b, and an upright rod 5C of a required length. A fitting hole 6α for the overhanging bracket 4α of the column 4 and a pin insertion hole 6b are provided at the inclined boundary part, and a screw hole 7 for attaching the first spring is provided on the upper end surface. established,
A stepped hole 8 for mounting the @2 spring is formed in the center of the upright rod 50.

These four packet claws 5 can be opened and closed by fitting the fitting holes 6α into the tips of the overhanging brackets 4α on each side of the column 4 and inserting the pins 9 into the pin insertion holes 6b, respectively. It is pivotally supported.

The upper end of each side of the column 4 and the upper end of each packet claw 5 are connected by a first spring 1n made of a color memory alloy, and the lower end of each side of the column and the center of each packet claw 5 are connected to each other. They are connected to each other by a second spring 11 made of ordinary spring steel in the following manner.

The first spring 10 is made of titanium-nickel (or nickel-aluminum, copper-zinc), and is processed into a coil with several turns at natural length 1 (lcs~i, 5c+a) as shown in Figure 7A, and is kept at room temperature. It is easily deformed at 70°C.
It is heat-treated to return to its original shape at a temperature of ~80°C, and has eyelet-shaped stoppers 10α and 10b on both ends.
is fixed, the rectangular stop J410a at one end is fitted into the horizontal groove 4C at the upper end of the column 4, and fixed by screwing the bolt 12 into the screw hole 4b from above the column 4, and the other end is fixed. The circular stopper 10b is located at the inclined upper end 5. of the upright rod 5 of the packet claw 5. / is fixed by a bolt 12 at the upper end thereof, and is positioned directly below the nozzle 2b of the distributor 2.

In addition, the second spring 11 is made of a normal spring material and has a spring force stronger than that of the first spring 10 at room temperature, and the length and number of coils are different from that of the first spring 10 as shown in the pJZ diagram. In almost the same way, a rectangular eyelet-shaped stopper 11α is fixed to one end, and a conical enlarged part 11b is formed at the other end, and the stopper 11α at one end is attached to a horizontal groove at the lower end of the column 4. 4
The bolt 12 is fitted into the screw hole 4b from below the column body 4.
The enlarged portion 11b at the other end is inserted into the stepped hole 8 at the center of the upright rod 5C of the packet claw 5, and is secured by a two-split stopper 16 as shown in FIG. 7C.

Therefore, under normal conditions at room temperature, the four packet claws 5 are drawn toward the column 4 by the spring force of the second spring 11, and the claw plates 5α are brought together and closed as shown by the solid line in FIG. The upper first spring 10 is deformed so as to be elongated.

When using it, as in the past, on the bridge of the storage pool of the fuel assembly, the position of the foreign object M that has fallen into the pool is monitored with a television camera, and the operating rod 1 is inserted into the pool. If, as shown in Fig. 3, the lower end of the packet is placed directly above the foreign object M and the centrally drained water is introduced, the hot water enters the distributor 2 through the central pipe 3 and flows through each downward nozzle 2b. 1 spring 10.

Therefore, the first spring 10 is heated to a predetermined variable temperature, and immediately returns to its original processed shape and shrinks to the dotted line state, so that the upper end of each packet claw 5 is directed toward the columnar body 4. ] and open in a dotted line shape around the pivot pin 9.

If each claw plate 5α is brought into contact with the bottom of the pool using that lump, and the supply of hot water is stopped, the temperature of the first spring 1o will rapidly drop due to the influence of the pool water, and the spring of the second spring will drop. Due to the force, each packet claw 5 closes into a solid line shape and collects the foreign matter M.

Then, bring this onto the collection packet, operate the cock 3α again to spray hot water onto the first spring 10, open each packet claw 5, and store the collected foreign matter M into the collection packet.

In the illustrated example, the column 4 is shown as having a rectangular shape from the viewpoint of ease of manufacture, and the first and second springs 10 and 11 are shown as having a coil shape. However, the column is not limited to this. The body is circular,
Even if the spring has a different shape, such as a wave shape, its function remains the same.
Further, the packet claws 5 may also be provided on three sides of the columnar body 4 so that the claw plates 5α form one-third of a circle.

As described above, in the present invention, the upper end of the column provided at the lower end of the pipe-like operating rod and the upper end of the upright rod of the packet claw each pivoted on a plurality of brackets of the column are connected to a shape memory alloy tube. 1 spring, and the lower end of the column and the center of the erecting rod of each packet claw are connected by a second spring made of spring copper.
Since the packet claws are opened and closed by spraying hot water onto the first spring or by stopping the first spring, the storage pool of the nuclear fuel assembly can be operated calmly without causing bubbles, compared to conventional methods that use compressed air. Since the release of radioactive substances in the pool is prevented, there is no risk of contaminating the atmosphere, and since no piston member or switching means are used, the structure is simple, lightweight, and easy to manufacture.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the state of foreign matter collection in the storage pool. FIG. 2 is a side view of a part of a conventional collection device. FIG. 6 is a side view of an embodiment of the invention. FIG. 4 is a perspective view of the packet claw. FIG. 5A is a partially cutaway side view of the distributor. The opening in the figure is its bottom view. Figure 6A is a half-sectional side view of the column. The opening in the figure is its bottom view. Figure 7A is a plan view of the first and second springs. Figure C is a front view of the stopper. In the diagram, 1...operating rod, 2...distributor, 2α
... Lip, 2b... Nozzle, 6... Pipe, 6α... Kotsukyu 4.
... Column body, 4α ... Overhang bracket, 4b ... Screw hole, 4c ... Horizontal groove, 5 ...
Packet claw, 5α...claw plate, 5b...outer circumference L
5o... Standing rod, 6α... Fitting hole,
7...Screw hole, 8...Stepped hole,
10...first spring, 11...second spring,
12... Bolt, 13... Stop, Patent applicant Makoto Sanada, representative of Nuclear Fuel Engineering M Hayashi Shiki Company - Funeral 1 Illustration Horse 2

Claims (1)

[Claims] At the lower end of the pipe-shaped operating lever of the required length, there is a pipe on the upper surface that extends upward through the operating lever and is connected to the water heater, and on the lower surface... J! A hollow distributor provided with several nozzles is fixed, and vI is placed inside the nozzles on the bottom surface of the distributor.
A column body having several overhanging brackets is attached, and each bracket has a packet claw, which is composed of a claw plate, an outer peripheral wall, and an upright rod whose upper end slopes outward, pivoted to open and close freely. The lower end of the column and the upper end of each packet claw are connected to each other by a first spring made of shape memory alloy on the lower side of the nozzle, and the lower end of the column and the center of the upright rod of each packet claw are connected to a second spring made of spring steel. A foreign matter collection device in which each packet claw is connected by a spring, and each packet claw is closed in a state of normal humidity, and one spring is expanded and deformed.