TRANSPORT PACKAGING KIT FOR TRANSPORTING URANIUM-CONTAINING FISSION MATERIALS

Abstract

 The invention relates to packaging kits intended for the transport and storage while in transit of radioactive materials. The kit comprises a container, provided with a shock damper and a double-shell assembly, each shell thereof being in the form of a barrel with a sealed lid thereon, which is arranged facing the bottom of an external reinforced casing, an inner shell of the container comprises a case with slots for placing vessels with a uranium-containing fission material, while free cavities in the case are filled with a neutron shielding material, the shock damper is located on the outer surface of the external reinforced casing of the container, said damper is made of solid wood impregnated with a flame retardant composition with an outer cladding of steel sheet, and a refractory material is laid between the damper and the cladding.

Description

Technical field

[0001] The invention relates to packaging kits intended for the transportation and transit storage of fission materials by all types of transportation, including air transportation.

Background of the invention

[0002] In accordance with the radiation safety standards and IAEA recommendations, transport packaging kits (TPK) intended for the transportation and transit storage of radioactive materials shall provide high radiation-protective and strength properties, including emergency situations that may occur during transportation and storage of radioactive material, especially by air transport: in accordance with IAEA safety requirements N° SSR-6, packages for fission materials intended for air transportation shall pass enhanced thermal tests, when the package is kept in a thermal environment for 60 minutes, and the test for collision with a target at a speed of at least 90 m/s.

[0003] A container is known (see patent RU 2175457, G21F5/00, E05G1/024), which is designed for the air transportation of dangerous items and contains an outer metal shell, where a thermal protection made of wood and an inner container made of a metal casing and thermal protection made of wood, equipped with an envelope for a cargo being transported, are installed one after another.

[0004] The known container has the following disadvantages:

• the container is not intended for transportation of nuclear hazardous materials;
• the design of the container does not ensure the radiation and nuclear safety of the transported materials.

[0005] The transport packaging kit (TPK) is known for the transportation of spent nuclear fuel - fuel assemblies of a nuclear reactor by all modes of transportation, including air transport (see patent RU 2581648, G21F5/00), i.e. a prototype, which is a container consisting of an inner and external shells, on which during transportation the removable shock dampers are mounted, fastened to the container with a bolted connection, while the dampers are made of titanium alloy and have a ribbed surface.

[0006] The disadvantages of this transport packaging kit (TPK) include the restriction on the nomenclature of the transported fission material, associated with the design of its sealing system; low use workability associated with the need to install / remove damping devices when loading / unloading the contents being transported.

Summary of the invention

[0007] The technical problem to be solved by the invention is the creation of a TPK design that does not allow the opening of the container casing, leading to leakage, to dispersion of the transported fission material, redistribution of material inside the package with loss of material spacing, thermal effects and ignition of TPK components with simultaneous increase in the TPK use workability.

[0008] The technical result of creating such a design of the transport packaging kit (TPK) is to meet the requirements of radiation and nuclear safety during the transportation and transit storage of nuclear radioactive fission and to improve the operating characteristics of the transport packaging kit (TPK).

[0009] The stated technical problem is solved providing a transport packaging kit for transporting uranium-containing fission materials, comprising a container equipped with a shock damper and being a double-shell assembly, each shell thereof being in the form of a barrel with a sealed lid thereon, where the lid of an inner shell is arranged facing the bottom of the external reinforced casing. According to the present invention, the inner shell of the container is provided with a case having slots for placing vessels with a uranium-containing fission material, while free cavities of the case are filled with neutron shielding material. The shock damper is mounted on the outer surface of the external reinforced casing of the container and is made of solid wood impregnated with a flame retardant composition and with an outer cladding made of steel sheet, and a refractory material is laid between the damper and the cladding.

[0010] The problem is also solved by the container wherein the case placed in the inner shell of the container can have five slots designed to place vessels with uranium-containing fission material. It is possible to place two vessels in each slot one above the other.

[0011] As a neutron shielding material, for example, boron carbide powder can be used.

[0012] MBOR fabric can be used as a refractory material to cover a solid wood acting as a shock damper.

[0013] At the top of the steel sheet intended for cladding the solid wood, four lifting eyes are fixed by welding, serving to tilt the transport packaging kit, and four supports are provided at the bottom.

[0014] The proposed design of the transport packaging kit allows to solve the above indicated technical problem.

[0015] The implementation of the transport packaging kit container as a double-shell, the installation of the inner container with a lid facing the bottom of the external reinforced container, and the use of a shock damper in the design of the transport packaging kit (TPK), the damper covering the outer surface of the container, prevent the "casing - lid" joint of both the container and its external reinforced casing from opening, depending on points of application of external load under emergency conditions of transportation. As a result, leakage or dispersion of the transported uranium-containing fission content and its release into the environment is prevented. The use of two hermetically sealed lids in the transport packaging kit (TPK) design ensures compliance with the requirements of the IAEA rules to prevent the redistribution of radioactive contents inside the package. The use of refractory materials in the design of the transport packaging kit (TPK) makes it possible to exclude the ignition of the shock damper, ensuring the safety of the sealing gaskets during thermal effects on the package.

[0016] The use of a case with slots for placing vessels with a uranium-containing fission content in the inner shell of the transport packaging kit (TPK) container and filling the free cavities of the case with a neutron shielding material, provide placement of uranium-containing fission content spaced apart.

[0017] The absence of the need to install / remove damping devices when loading / unloading the transported contents increases labor productivity when using the transport packaging kit (TPK) of the proposed design, increases the use workability of the transport packaging kit (TPK), and improves operating characteristics of the TPK.

Brief description of drawings

[0018] The concept of the invention is explained by the drawings.

Fig. 1 shows a transport packaging kit (TPK) container for transporting uranium-containing fission materials, a perspective view.

Fig. 2 shows the fastening of the lid of the external casing of the container (fragment).

Fig. 3 shows the fastening of the lid of the inner shell of the container (fragment).

Fig. 4 shows a vessel for uranium-containing fission material, placed in the slot of the case in the inner shell of the container.

Detailed description

[0019] A transport packaging kit (TPK) comprises a container having an external reinforced casing (1), closed with a lid (2), and an inner shell (3), placed inside of the casing (1) and closed by a lid (4). A case (5) is located inside of the casing (3), the case (5) having slots for accommodate vessels (6) for a transported uranium-containing fission material.

[0020] The external casing (1) is made in the form of a steel barrel, with a shock damper (7) installed on the outer surface thereof, the damper (7) made, for example, of solid wood impregnated with a flame retardant composition and having an outer cladding of a steel sheet (8). A refractory material (9) is placed between the shock damper (7) and the steel sheet (8), the refractory material being, for example, a MBOR fabric, and designed to protect the shock damper (7) from temperature effects in emergency situations. At the side of the lid (2) of the casing (1) a plug (10) is provided in the form of a disk made of damping material, for example, wood, coated with a flame retardant composition and having a sheet steel cladding.

[0021] The lid (2) of the external casing (1), made of a thick sheet material, is attached to the casing (1) via reinforced bolts (11). A sealing gasket (12) is installed between the casing (1) and the lid (2), which prevents the loss of the transported contents both in normal and emergency situations.

[0022] The plug (10) is attached to the external casing (1) with the use of nuts (13). A sealing gasket is installed between the plug (10) and the casing (1), which prevents atmospheric precipitation from entering the casing (1) (not shown).

[0023] At the top of the steel sheet (8) used as a solid wood cladding, four lifting eyes (14) are fixed by welding, designed to lift and move the transport packaging kit (TPK) as well as to secure it with the help of couplers in the vehicle.

[0024] Four supports (15) are welded to the surface of the casing (1) at the upper part, intended for tiered storage of the transport packaging kit (TPK), and four supports (16) are welded at the bottom.

[0025] The lid (4), made of a thick-walled material, is attached to the inner shell (3), made in the form of a barrel of a thick-walled material, using reinforced bolts (17). A sealing gasket (18) is installed between the shell (3) and the lid (4), which prevents the loss of the transported radioactive contents, both in normal and emergency situations.

[0026] On the outer surface of the bottom of the casing (3) and on the outer surface of the lid (4), special lifting eyes (19) are welded, designed for installing/removing the shell (3) of the container into the external reinforced casing (1).

[0027] Inside the shell (3) there is a case (5) in the form of a drum, for example, having several slots for accommodating vessels (6) with transported contents. The free cavities of the case (5) are filled with a neutron-absorbing material (20), for example, boron carbide powder B₄C.

[0028] The vessel (6) is a cylindrical casing (21) with a screw lid (22).

[0029] The use of the transport packaging kit (TPK) is carried out as follows.

[0030] Uranium-containing fission material, for example, in the form of a powder, crumbs, tablets, metal ingots, is packed in a polyethylene case, which is placed inside the casing (21) of the vessel (6) and closed with a screw lid (22). The vessels (6) with the material packed therein are placed in the slots of the case (5) located in the inner cavities of the container shell (3). The shell (3) is closed with a lid (4), which is attached to the casing with reinforced bolts (17). With the help of lifting equipment, the filled and closed shell (3) is placed into the external reinforced casing (1) with the lid (4) down. The lid (2) of the external casing (1) is installed and fastened with reinforced bolts (11). Then a plug (10) is installed and fastened with nuts (13). After that, contamination of the outer surface of the transport packaging kit (TPK) is checked in accordance with the requirements of the IAEA rules.

[0031] The transport packaging kit (TPK) of the proposed design passed the tests. The declared strength properties are confirmed. The possibility of expanding the range of transported radioactive contents is provided.

[0032] Thus, the use of the transport packaging kit (TPK) of the proposed design for the transportation of uranium-containing fission materials is guaranteed to ensure the radiation and nuclear safety of the transported materials by any mode of transportation, including air transport, while the use of the TPK of the proposed design is less costly and more technologically simple compared to existing samples.

Claims

1. A transport packaging kit for transporting uranium-containing fission materials, comprising a container provided with a shock damper, the container having a double-shell structure, each shell thereof being in the form of a barrel with a sealed lid thereon, wherein the lid of an inner shell is arranged facing the bottom of an external casing, characterized in that that the inner shell of the container is provided with a case having slots for placing vessels with a uranium-containing fission material, while free cavities in the case are filled with neutron shielding material, wherein the shock damper is mounted on the outer surface of the container, said damper is made of solid wood impregnated with a flame retardant composition covered by a refractory material and having an outer steel sheet cladding.

2. The transport packaging kit according to Claim 1, wherein the case has five slots for placing the vessels with uranium-containing fission material.

3. The transport packaging kit according to Claim 1, wherein two vessels with uranium-containing fission material are placed in each slot one above the other.

4. The transport packaging kit according to Claim 1, wherein boron carbide powder is used as the neutron shielding material.

5. The transport packaging kit according to Claim 1, wherein MBOR fabric is placed between the solid wood and the steel sheet cladding.

6. The transport packaging kit according to Claim 1, wherein four lifting eyes are welded at the top part of the steel sheet cladding.

7. The transport packaging kit according to Claim 1, wherein four supports are provided at the bottom of the shell.

Drawing