RU2565058C1 - Method to load bundle of fuel elements of spent double-bundle fuel assembly of nuclear reactor into ampoule and device for its realisation - Google Patents

Abstract

FIELD: power engineering.

SUBSTANCE: invention relates to transportation and subsequent storage of a spent fuel assembly (FA) of a nuclear reactor. In the method to load a bundle of fuel elements of a spent double-bundle fuel assembly, the ampoule for loading is supplied with a quick-detachable spacing ring. The ring is temporarily fixed on the cover and excludes its fixation before installation of the bindle of fuel elements into the ampoule. The ring is removed before closure of the ampoule cover. The device for realisation of the above method is made as a quick-detachable spacing ring representing a coiled elastic zigzag-shaped belt with a flat bent end and fixed by the other end to a boxy frame. The frame has a slot for connection and a window for spaced opening of the ring. At the same time the flat bent end of the spacing ring is made as a continuation of the zigzag-shaped belt and is made as an elastic tab fixed in the boxy frame.

EFFECT: elimination of the necessity of ampoule positioning and spaced opening of locks of ampoule covers in a protective chamber before supply of ampoules into it.

3 cl, 5 dwg

Description

This invention relates to a method for cutting a two-beam spent fuel assembly of a nuclear reactor, providing the possibility of its transportation to a long-term storage.

The invention is known "Ampoule for spent fuel Assembly" (patent RU No. 2353010 C1, 21F 5/008, publ. 04/20/2009). The ampoule contains a cylindrical body with a bottom and a cover. The lid is fixed in the upper part of the casing with a locking device in the form of a spring split ring mounted on the lid, and, in a free state, included in the annular groove of the ampoule body.

To load the bundle of fuel elements (fuel elements) of the finished spent fuel assembly, the ampoules, in a closed form, are fed into a protective chamber. Using a special device, the ampoule is positioned, the spring split ring in the ampoule cover is evenly crimped to a diameter that ensures the exit of the ring from the groove of the ampoule body. This makes it possible to remove the ampoule cover using a crane. After loading the bundle of fuel rods into the ampoule, the cover is installed with a crane as a seat in the ampoule body, the spring split ring snaps into the groove of the ampoule body and the cover is fixed to the case.

The invention is known "Device for equipping ampoules" (patent RU No. 2444799, G21F 7/00, publ. March 10, 2012), which is a mechanism for opening the lock of the lid of the ampoule with the positioning device of the ampoule (in angle and height), which makes it possible to operate lock opening mechanism.

The invention is known "A method of cutting a spent two-beam fuel assembly of a nuclear reactor for its subsequent storage and a cutting chamber for implementing the method" (RU patent No. 2226011 C2, G21F 7/06, published on March 20, 2004).

Also known is the invention “A method for loading a spent fuel assembly of a nuclear reactor into an ampoule for its subsequent storage and an ampoule for implementing the method” (RU patent No. 2323246 C2, G21F 7/00, published on June 27, 2008).

In these inventions, the ampoules for loading the bundles of fuel rods of the separated spent fuel assemblies are fed into the protective chamber (in the cover of the transport container) in a closed form. At the loading post, using the known device for equipping ampoules, the locks of the caps of the ampoules are opened, the caps are removed from the ampoules. Bundles of fuel rods are loaded into ampoules. Then the ampoules are closed with lids, transported by a crane and installed in a case.

A disadvantage of the known methods for handling ampoules is that their implementation requires the use of an ampoule positioning device and a remotely controlled opening mechanism for the ampoule lid lock in the protective chamber, which reduces the performance and reliability of the protective chamber equipment complex.

The basis of the invention was the task of developing a method for loading a bundle of fuel rods into an ampoule, the implementation of which eliminates the need for positioning the ampoules and remote opening the locks of the caps of the ampoules in the protective chamber. Opening the locks of the capsules of the ampoules is carried out before feeding the ampoules into the protective chamber.

In the implementation of the invention can be obtained, in particular, the following technical results:

- reduction of equipment in the protective chamber;

- productivity increase;

- increase the reliability of the complex equipment of the protective chamber.

As a solution to the problem, it is possible to achieve a technical result, a method for loading an spent two-beam fuel assembly of a nuclear reactor into an ampoule bundle for subsequent storage, including installing a bundle of fuel rods in an ampoule and fixing the lid on the ampoule body, according to the invention, the ampoule is fed for loading with a quick-detachable remote a ring temporarily mounted on the lid, excluding its fixation before installing the fuel rod bundle in the ampoule, which is removed before closing the ampoule cover .

A device for implementing the above method is made in the form of a quick-detachable spacer ring, which is a rolled elastic zigzag ribbon with a flat bent end and fastened to the other end with a box-shaped frame having a slot for connection and a window for remote opening of the ring. It is advisable to make the flat bent end of the spacer ring as a continuation of the zigzag ribbon and make it in the form of an elastic tongue, which is fixed in a box-shaped frame.

The technical result is achieved by opening the ampoule cover before moving the ampoule into the protective chamber and installing a bundle of fuel rods in it, and transferring the ampoules to the protective chamber so that the caps are not fixed in the cases, while quick-detachable distance rings are installed on the seats of the caps of the ampoules, and when installing the cover on the ampoule body, the spring split ring of the cover is placed above the annular groove of the case, excluding the fixation of the covers on the cases, which reduces the equipment in the protective chamber D when the process step of positioning the ampoule and the ampoule opening lid lock and, consequently, improves the performance and increases the reliability of the set of equipment housing chamber.

The claimed invention is illustrated by the drawings presented in figures 1 to 5:

figure 1 - ampoule with an unsecured lid;

figure 2 - placement of the spacer ring on the lid of the ampoule-place A (figure 1);

figure 3 - spacer ring;

figure 4 - spacer ring - section bB (figure 3);

figure 5 - the connection node of the spacer ring - place B (figure 4).

This problem is solved in that the ampoules are transferred to the protective chamber so that the caps 1 (Fig. 1) remain not fixed in the housings 2. This is achieved by installing quick-detachable spacer rings 3 on the seats of the caps of the ampoules (Fig. 2). In this case, when installing the lid 1 on the ampoule body, the spring split ring 4 (FIG. 2) of the lid is placed above the annular groove 5 (FIG. 2) of the housing, which eliminates the fixation of the covers 1 on the housings.

The device of the quick-release spacer ring 3 (Fig. 3) is a zigzag tape 7 (Fig. 4) having elastic properties. One end of the tape 7 is bent and pressed against the plane of the tape, forming a tongue 8 (figure 5), the other is connected to a box-shaped frame 9 having a slot 10 (figure 5) and a window 11. For the formation of the spacer ring 3, the tape 7 must be wrapped around the seat of the lid 1 of the ampoule (above the spring split ring) and the tongue 8 of the tape 7 are inserted into the slot 10 of the box frame 9. In this case, the tongue 8 clicks and the distance ring 3 is blocked.

To remove the spacer ring 3, you must click on the tongue 8, which due to the elasticity of the tape 7 will come out of the slot frame 9, and the spacer ring 3 will be opened.

The box-shaped design of the frame 9 protects the tongue 8 from accidental influences during technological operations with the ampoule, since it is covered by the walls of the frame 9.

Work on the proposed method for loading ampoules with fuel rods using the proposed device is as follows.

A transport container with empty ampoules, designated for loading spent nuclear fuel (SNF), is installed near the ampoule entry control stand, the lid is removed from it. The ampoules are alternately removed from the container cover and, with the help of snap-ins, opened for incoming inspection. At the same time, during the input control of ampoules, spacers 3 are installed on the seats of the covers 1, then the ampoules are loaded back into the case. The transport container is closed with a lid and moved under the receiving device of the protective chamber, where the cover is moved by a crane into the protective chamber, into the unloading zone of empty and the installation of loaded ampoules.

With a crane with two pendants, they take the lid with one gripper, the ampoule body with the other, and move them to the loading post with fuel rods. The ampoule body is installed in the loading slot, then a bundle of fuel rods 6 is loaded into it (FIG. 1). Using the copy manipulator, pressing the tongue 8 through the window 11 (Fig. 5) removes the spacer ring 3 from the lid 1 of the ampoule. After that, the cover 1 is installed on the ampoule body, the spring split ring of the cap is latched in the groove of the body and the ampoule is locked. The spacer ring 3 is placed in a special container.

The crane lifts the loaded ampoule, moves it to the case and installs it in a free cell of the case.

After filling in all the cells, the cover is installed with a tap into the container, which is then removed to prepare for transportation.

The container with the spacer rings 3, through the transfer gateway, is removed from the protective chamber. After decontamination (if necessary), the container and spacer rings can be reused.

Claims (3)

1. The method of loading into an ampoule of a bundle of fuel rods of an spent two-beam fuel assembly of a nuclear reactor for subsequent storage, comprising installing a bundle of fuel rods in an ampoule and fixing the lid on the ampoule body, characterized in that the ampoule is fed under loading with a quick-release spacer ring temporarily mounted on the lid, excluding its fixation before installing the fuel rod bundle in the ampoule, removed before closing the ampoule cover. 2. The device for implementing the method according to claim 1, made in the form of a quick-detachable spacer ring, which is a rolled elastic zigzag ribbon with a flat bent end and fastened to the other end with a box-shaped frame having a slot for connection and a window for remote opening of the ring. 3. The device according to claim 2, characterized in that the flat bent end of the spacer ring is made by a continuation of the zigzag ribbon and is made in the form of an elastic tongue, which is fixed in a box-shaped frame.

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