SU1790792A3 - Transport container for worked out fuel elements - Google Patents

Description

The invention relates to devices for transporting and storing spent nuclear fuel of nuclear power plants and can be used in nuclear engineering.

The TK-13 container is known, where several rows of circle-shaped plates are fixed on the central pipe, connected in pairs by hexagonal pipes serving as fuel assembly protection (see working drawing PO IZ No. 1332.00.00.000).

Known container having cutouts in the outer row. ? j

A cover is known for the same container TK-13 for spent fuel assemblies, which is a welded structure consisting of a base in the form of a circle and a central pipe, to which hexagonal pipes are attached in 2 rows using 2 spacing grids and an upper faceted belt.

A disadvantage of the known design is the lack of sufficient thermal connection between the hexagonal pipes due to the presence of air gaps between them and the solid metal walls of the pipes in which the OTV C are located, which makes it difficult to remove heat from the cassettes to the walls of the container from the cassettes of the inner row to the cassettes of the outer row, leads to overheating of the cassettes and their destruction in the event of an emergency.

The purpose of the invention is to increase the reliability of the structure by improving heat dissipation from the central cassettes to external and from external cassettes to the walls of the container.

This goal is achieved by the fact that the inner side of the casing wall is made in the form of a polyhedron, the faces of which are parallel to the faces of the adjacent hexagonal pipes, and the faces of the hexagonal pipes have holes whose axes are offset relative to the holes of the nearest face of the adjacent hexagonal pipe, • exceeding the diameter of the holes .

To achieve this goal, it is necessary to change the shape of the inner surface of the container body. To create equal conditions for heat transfer of all cassettes of the outer row of the cover with the wall of the casing, the inner surface of the container should repeat the shape of the outer row of tubes of the cover with the same gap, providing convective heat transfer from the cassettes to the wall.

The claimed solution differs from the prototype in that the SFA. Installed in perforated hexagonal pipes in a container body that repeats the shape of this outer row of pipes, they maximize the use of convective and radiation heat transfer, preserving nuclear and radiation safety and reducing the possibility of cartridge overheating in emergency situations. Overheating in emergency situations will begin in the internal row of SFA, as it is these SFAs. are in conditions of more difficult heat dissipation, and nuclear safety without reducing the capacity of the cover does not allow gaps to be provided to ensure heat dissipation from the inner row of cartridges. Therefore, the perforation of the inner row of pipes improves heat dissipation from the inner row of SFAs, and the perforation of the outer row of pipes and equal heat removal conditions make the entire outer row of SFAs cooler than their counterparts and, as a result, perceive and transfer more heat from the SFA to the container body, reducing their average temperature. A temperature margin appears in the SFA of the inner row, allowing them to maintain integrity in emergency situations.

In Fig.1 shows a container: in Fig.2 a section aa in Fig.1; in Fig.Z - node I.

A container with a cover for transporting radioactive waste, consisting of a container body 1, a container cover 2, a cover 3 with two rows of hexagonal pipes - external 4 and internal 5, installed between two rows of pipe boards - lower 7 and upper 8, mounted on the central pipe 6. The central pipe 6 is installed on the base 9, on which a row of hexagonal pipes is installed around the circumference 5. Around the inner row of pipes, an outer row of pipes is installed 4. FAs with spent fuel are installed in the pipes of the outer and inner rows 10. Tru would distance themselves by gaskets 11, ensuring nuclear safety of the SFA.

The heat released from the outer row of the SFA is transferred to the container body. The container body has a large heat transfer surface inside and out. Therefore, the cassettes of the outer row have intense heat exchange with the casing and through it with the external environment and are therefore cooler than the cassettes of the inner row. The heat from the cassettes of the inner row is transferred by the cassettes of the outer row and convective heat transfer directly to the casing.

Claims (1)

Claim A container for transporting spent fuel assemblies, including a housing, a lid and a cover containing hexagonal pipes for accommodating the spent fuel assemblies, the corresponding faces of the hexagonal pipes being parallel to one another, characterized in that, for the purpose of improving reliability, the inner side the walls of the body are made in the form of a polyhedron, the faces of which are parallel to the faces of the adjacent hexagonal pipes, and the faces of the hexagonal pipes have holes whose axes are offset relative to the axes of the holes the distance of the nearest face of the adjacent hexagonal pipe by an amount exceeding the diameter of the holes. Order 376 Circulation Subscription VNIIIPI State Committee for Inventions and Discoveries at the USSR State Committee for Science and Technology! ’3035. Moscow, Zh-35, Raushskaya nab., 4/5> _ ______________, ______________ Prospectus-> ъ .. Pelsky Combine Patent, Uzhhorod, st., Gagarina, 101