Heat insulation structure of new fuel assembly transport container and new fuel assembly transport container

Abstract

Provided are a heat insulation structure of a new fuel assembly transport container and the new fuel assembly transport container. The container mainly comprises an inner containment shell, an outer containment shell and a heat insulation structure. The heat insulation structure comprises a heat insulation cylinder, a heat insulation bottom and a heat insulation cover, which are respectively located in the annular, bottom and top cavities separated by the inner and outer containment shells to play a heat insulation role, and the three have similar structures and are mainly composed of heat insulation blocks and support blocks, wherein the heat insulation blocks are made of aluminum silicate composite fiber castable and the support blocks, the inner containment shell, the outer containment shell and other components are cast into an integral structure that cannot be disassembled. In this way, the heat insulation structure can be suitable for narrow installation space, realize compact and accurate design, and have heat insulation and shock absorption and buffering functions for the transport container, so that nuclear events / nuclear accidents of nuclear fuel leakage will not occur when the same or equivalent heat resistance test listed in GB11806 occurs during the transport of new fuel assemblies.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of transportation, and more particularly to a heat insulation structure of a new fuel assembly transport container and the new fuel assembly transport container. BACKGROUND

[0002] A new fuel assembly transport container is a container specially designed for transporting nuclear fuel assemblies (new fuel assemblies) just produced from a nuclear fuel factory, to ensure the critical safety of the new fuel assemblies. According to the Chinese national standard GB11806-2019, in the heat resistance test (commonly known as the 30-minute fire test), the new fuel assembly transport container should be able to prevent the fuel assembly from overheating and melting or being damaged to cause the leakage of radioactive substances, thereby avoiding the occurrence of nuclear events or nuclear accidents. Therefore, in order to enable the new fuel assembly transport container to withstand the same or comparable level of transportation accidents as the heat resistance test, the design of the heat insulation structure is very necessary and important.

[0003] However, there is currently a lack of heat insulation structures of new fuel assembly transport containers suitable for low-temperature reactors. The existing heat insulation structures mainly use solid forming materials such as heat insulation blankets. These solid materials are difficult to install into narrow spaces, which is not conducive to the compact design of the new fuel assembly transport container. The installation space, especially the corners, is also difficult to be uniformly filled with solid heat insulation materials, which cannot achieve precise design, so that the heat insulation structure needs to have a larger design allowance. SUMMARY

[0004] The present application is made in view of the above state of the art. The purpose of the present application is to provide a heat insulation structure of a new fuel assembly transport container and the new fuel assembly transport container, which can overcome or alleviate at least one of the disadvantages described in the background.

[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions.

[0006] The present application provides a new fuel assembly transport container heat insulation structure, the new fuel assembly transport container includes an inner containment shell for containing a new fuel assembly and an outer containment shell for containing the inner containment shell, the heat insulation structure is used for separating the inner containment shell and the outer containment shell, the heat insulation structure includes: a heat insulation cylinder including a cylinder heat insulation block, the cylinder heat insulation block includes aluminum silicate composite fibers, the cylinder heat insulation block is configured to be cast between the outer peripheral surface of the inner containment shell and the inner peripheral surface of the outer containment shell; a heat insulation bottom configured to be installed between the axial one side end of the inner containment shell and the axial one side end of the outer containment shell, the heat insulation bottom includes a bottom heat insulation block and a bottom support block, the bottom heat insulation block includes aluminum silicate composite fibers, the bottom support block includes wood, the bottom heat insulation block and the bottom support block are arranged in the axial direction of the heat insulation bottom; and a heat insulation cover configured to be installed between the axial other side end of the inner containment shell and the axial other side end of the outer containment shell, the heat insulation cover includes a top heat insulation block and a top support block, the top heat insulation block includes aluminum silicate composite fibers, the top support block includes wood, the top heat insulation block and the top support block are arranged in the axial direction of the heat insulation cover.

[0007] In an optional scheme, the heat insulation bottom further includes a bottom box ring, a bottom box cover plate and a bottom pin, the bottom box cover plate is arranged at the axial one side end of the bottom box ring, the bottom box cover plate is fixedly connected with the bottom box ring, the bottom heat insulation block is configured to be deposited at the axial one side end of the bottom box ring in a cast manner, the bottom box cover plate is located at the axial one side of the bottom heat insulation block, the axial one side end surface of the bottom support block and the axial other side end surface of the bottom heat insulation block are bonded with each other, the bottom pin is made of wood, the bottom box ring is sleeved on the bottom support block, and the bottom box ring and the bottom support block are pin-connected with each other through the bottom pin.

[0008] In another optional scheme, the bottom box ring defines a bottom exhaust port, the bottom exhaust port is a notch at the axial one side end of the bottom box ring, the bottom box ring is sleeved on the bottom box cover plate, the bottom box cover plate and the bottom exhaust port are staggered with each other in the radial direction of the bottom box ring, and the inner side cavity of the outer containment shell can be communicated with the cavity in the inner containment shell through the bottom exhaust port.

[0009] In another optional scheme, the bottom box ring defines an exhaust groove, the exhaust groove is arranged on the peripheral surface of the bottom box ring and extends along the circumference of the bottom box ring, and the inner side cavity of the outer containment shell can be communicated with the cavity in the inner containment shell through the exhaust groove.

[0010] In another optional solution, the bottom support block defines a positioning hole arranged at an axial other side end of the bottom support block, and an axial one side end of the inner containment shell is configured to be inserted into the positioning hole.

[0011] In another optional solution, the heat insulation cover further comprises a cover box ring, a cover box sealing plate and a top pin, the cover box sealing plate is arranged at an axial other side end of the cover box ring, the cover box sealing plate is fixedly connected with the cover box ring, the top heat insulation block is configured to be deposited at an axial other side end of the cover box ring in a pouring manner, the cover box sealing plate is located at an axial other side of the top heat insulation block, an axial other side end surface of the top support block and an axial one side end surface of the top heat insulation block are bonded with each other, the top pin is made of wood, the cover box ring is sleeved on the top support block, and the cover box ring and the top support block are pin-connected with each other through the top pin.

[0012] In another optional solution, the cover box ring defines a top exhaust port which is a notch at an axial other side end of the cover box ring, the cover box ring is sleeved on the cover box sealing plate, the cover box sealing plate and the top exhaust port are staggered with each other in a radial direction of the cover box ring, and an inner cavity of the outer containment shell can be communicated with a cavity in the inner containment shell through the top exhaust port.

[0013] In another optional solution, the heat insulation cover further comprises a ring body, a compensation pad and a connecting plate, the ring body comprises wood, the ring body is sleeved on the cover box ring, the ring body and the cover box ring are bonded with each other, an axial other side end of the ring body is used to abut against the outer containment shell, a radial outer side of the ring body forms a ring-shaped space for storing gas, the compensation pad is made of wood or rubber, the compensation pad is bonded with the top support block through the connecting plate, and an axial one side end of the compensation pad abuts against the inner containment shell.

[0014] In another optional solution, the heat insulation cylinder further comprises a cylinder support block, the cylinder support block is made of wood, and the cylinder support block is configured to be installed between an outer peripheral surface of the inner containment shell and an inner peripheral surface of the outer containment shell.

[0015] The application further provides a new fuel assembly transportation container, which comprises the heat insulation structure, the inner containment shell and the outer containment shell.

[0016] By using the above technical solution, the heat insulation structure can be applied to a narrow installation space by using the aluminum silicate composite fiber pouring material and wood as a framework, the uniform heat insulation performance of the heat insulation structure can realize accurate design, so that a large design allowance is not required, and the heat insulation structure has a vibration damping and buffering function. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 A schematic view of a new fuel assembly transport container according to an embodiment of the present application is shown.

[0018] Figure 2 A front view of the new fuel assembly transport container in Figure 1

[0019] Figure 3 An exploded view of the new fuel assembly transport container in Figure 1

[0020] Figure 4 A sectional view of the heat insulation structure in Figure 1

[0021] Figure 5 A schematic view of the inner containment vessel in Figure 1

[0022] Figure 6 A schematic view of the heat insulation structure in Figure 1

[0023] Figure 7 A sectional view of the heat insulation bottom of the heat insulation structure in Figure 6

[0024] Figure 8 A schematic view of the bottom box ring of the heat insulation bottom in Figure 7

[0025] Figure 9 A sectional view of the heat insulation cover of the heat insulation structure in Figure 6

[0026] Figure 10 A schematic view of the cover box ring of the heat insulation cover in Figure 9

[0027] BRIEF DESCRIPTION OF DRAWINGS

[0028] 1 inner containment vessel;

[0029] 11 inner shell; 111 inner cylindrical body; 112 inner shell bottom plate; 113 inner shell cover plate;

[0030] 12 accelerometer mounting member;

[0031] 2 outer containment vessel;

[0032] 21 outer shell; 211 outer cylindrical body; 212 outer shell bottom plate; 213 end cover;

[0033] 22 vibration reduction structure;

[0034] 3 heat insulation structure;​​​​​​​​​

[0035] 31 Insulation cylinder; 311 Insulation block; 312 Support block;

[0036] 32 Insulated base; 321 Base box ring; 322 Base box sealing plate; 323 Base insulation block; 324 Base support block; 325 Base pin; 32a Positioning hole; 32b Vent groove; 32c Base vent;

[0037] 33 Insulation cover; 331 Cover ring; 332 Cover plate; 333 Hanging point shaft; 334 Top insulation block; 335 Top support block; 336 Top pin; 337 Ring body; 338 Compensation pad; 33a Top vent;

[0038] 4 new fuel components;

[0039] A represents the axial direction; R represents the radial direction; C represents the circumferential direction. Detailed Implementation

[0040] Exemplary embodiments of this application are described below with reference to the accompanying drawings. It should be understood that these specific descriptions are for teaching those skilled in the art how to implement this application only, and are not intended to exhaust all possible methods of this application, nor to limit the scope of this application.

[0041] In this application, unless otherwise specified, "one is threaded into another" means that one is threaded into another. "One is offset from another in a certain direction" means that, when viewed from that direction, one and the other do not overlap.

[0042] Figures 1 to 10 A novel fuel assembly transport container according to an embodiment of this application is shown, particularly a novel fuel assembly transport container suitable for boxed nuclear fuel assemblies in cryogenic reactors.

[0043] Reference Figures 1 to 4 The new fuel assembly transport container may include an inner enclosure 1, an outer enclosure 2, and a heat insulation structure 3. The inner enclosure 1 can accommodate the new fuel assembly 4, the outer enclosure 2 can accommodate the inner enclosure 1, and the heat insulation structure 3 can be disposed between the outer enclosure 2 and the inner enclosure 1.

[0044] Reference Figures 3 to 5 The inner housing 1 may include an inner housing 11 and an accelerometer mounting component 12.

[0045] The inner shell 11 may include an inner cylinder 111, an inner shell bottom plate 112, and an inner shell cover plate 113. Specifically, the inner shell 11 may be made of stainless steel, for example, austenitic stainless steel. The inner shell bottom plate 112 may be disposed at one axial end of the inner cylinder 111. Figure 4the right end portion of the inner housing 111), and is screwed with the inner cylinder 111. The inner housing cover plate 113 can be arranged at the axial other end portion of the inner cylinder 111 (the left end portion of the inner housing 111), and is screwed with the inner cylinder 111. The inner cylinder 111 can be sleeved on the new fuel assembly 4, so that the new fuel assembly 4 is limited in the radial direction R. The new fuel assembly 4 can be located between the inner housing bottom plate 112 and the inner housing cover plate 113, so that the new fuel assembly 4 is limited in the axial direction A. Figure 4

[0046] The accelerometers on the accelerometer mounting member 12 are used to measure the vibration acceleration of the new fuel assembly 4. Specifically, the accelerometer mounting member 12 can be fixedly pressed at the axial other end portion of the new fuel assembly 4 (the left end portion of the inner housing 111), and the accelerometers can be mounted on the accelerometer mounting member 12 through fasteners. The number of accelerometers can be multiple, and the multiple accelerometers can measure accelerations in multiple different directions, for example, the multiple different directions can be orthogonal to each other. The accelerometers can have a settable overload threshold, for example, the overload threshold can be 4g or 6g. During the entire transportation process, once the vibration acceleration of the new fuel assembly 4 reaches the overload threshold, the accelerometer can be triggered, and the overload event is recorded. Figure 4

[0047] Referring to Figures 1 to 4 , the outer containment shell 2 can include an outer shell 21 and a damping structure 22.

[0048] The outer shell 21 can include an outer cylinder 211, an outer shell bottom plate 212, and an end cover 213. Specifically, the outer shell 21 can be made of stainless steel, for example, can be made of austenitic stainless steel. The outer shell bottom plate 212 can be arranged at the axial one side end portion of the outer cylinder 211 (the right end portion of the outer housing 111), and is welded with the outer cylinder 211. The end cover 213 can be arranged at the axial other end portion of the outer cylinder 211 (the left end portion of the outer housing 111), and is detachably sealingly connected with the outer cylinder 211, for example, a sealing ring can be arranged between the end cover 213 and the outer cylinder 211. Figure 4 Figure 4

[0049] The damping structure 22 can be a structure with damping and buffering and supporting functions. Specifically, the damping structure 22 can be arranged on the surface of the outer shell 21 and protrude outward of the outer shell 21. The damping structure 22 can be fixed with the outer shell 21, for example, can be fixed with the outer shell 21 by welding or integrated as a whole. In the event of a mechanical transportation accident such as a fall or a dynamic crushing, the damping structure 22 can deform to absorb the destructive energy to the transportation container and its contents, thereby achieving the effect of maintaining the structural integrity of the new fuel assembly 4 and the sealing of the fuel cladding and the outer containment shell 2.

[0050] Referring to Figure 3 ,​​​​Figure 4 and Figure 6 The heat insulation structure 3 can include a heat insulation cylinder 31, a heat insulation bottom 32, and a heat insulation cover 33.

[0051] The heat insulation cylinder 31 can include a cylinder heat insulation block 311 and a cylinder support block 312.

[0052] The cylinder heat insulation block 311 can be obtained by casting. Specifically, the cylinder heat insulation block 311 can be casted by aluminum silicate composite fiber castable, and the castable can be formed into a cast block including aluminum silicate composite fiber after setting. The castable can be prepared from silicon dioxide (SiO2), diatomic aluminum (Al2O3), and a binder. The thermal conductivity of the cast block can be less than or equal to 0.16 W / (m·K). The maximum use temperature of the cast block can be greater than or equal to 1200°C. The volume density uniformity of the cast block can be less than or equal to 6%. The volume density uniformity of the cast block can be measured by sampling at typical positions, which can be specifically represented as (ρ max -ρ min ) / ρ avg . Wherein, ρ max is the maximum value of the sample volume density, ρ min is the minimum value of the sample volume density, and ρ avg is the average value of the sample volume density.

[0053] The cylinder support block 312 can be arranged coaxially with the cylinder heat insulation block 311. Specifically, the cylinder support block 312 can be made of wood, for example, can be made of pine. The inner circumferential surface of the cylinder support block 312 can be provided with a step. The cylinder support block 312 can be arranged at the other side (left side in Figure 4 ) of the cylinder heat insulation block 311 in the axial direction, and the axial one side end surface (right end surface in Figure 4 ) of the cylinder support block 312 can be bonded with the axial other side end surface (left end surface in Figure 4 ) of the cylinder heat insulation block 311.

[0054] Referring to Figure 7 and Figure 8 , the heat insulation bottom 32 can include a bottom box ring 321, a bottom box cover plate 322, a bottom heat insulation block 323, a bottom support block 324, and a bottom pin 325.

[0055] The bottom heat insulation block 323 can be obtained by casting. Specifically, the bottom box ring 321 and the bottom box cover plate 322 can be made of stainless steel, for example, can be made of austenitic stainless steel. The bottom box ring 321 can be sleeved on the bottom box cover plate 322. The bottom box cover plate 322 can be arranged at the axial one side end of the bottom box ring 321 (left end in Figure 7The bottom insulation block 323 may include aluminum silicate composite fibers, which can be deposited by casting onto one axial end of the bottom ring 321. Figure 7 The bottom box sealing plate 322 can be located on one axial side of the bottom heat insulation block 323 (at the lower end of the bottom box). For example, in this embodiment, the bottom heat insulation block 323 and the cylindrical heat insulation block 311 can be made of composite fiber castable with the same formulation.

[0056] The bottom ring 321 can define the vent groove 32b and the bottom vent 32c. Specifically, the outer circumferential surface of the bottom ring 321 can be provided with the vent groove 32b, which can extend circumferentially C. The axial end of the bottom ring 321 ( Figure 7 The lower end of the bottom box 322 may have a notch, which may be formed as a bottom vent 32c. The bottom vent 32c and the bottom box sealing plate 322 may be offset radially by a distance R, and the bottom of the bottom vent 32c may be aligned with one axial end face of the bottom box sealing plate 322. Figure 7 The lower end face of the inner enclosure 1 is flush with the outer enclosure 2, and multiple bottom vents 32c can be evenly arranged at intervals along the circumferential direction C. The cavity inside the inner enclosure 1 can communicate with the cavity inside the outer enclosure 2 through the vent groove 32b, the bottom vents 32c, and structural fitting gaps. Under high-temperature conditions such as burning, the high-temperature pyrolysis gases of the non-metallic material inside the inner enclosure 1 can be discharged from the outer enclosure 2 through the vent groove 32b, the bottom vents 32c, and structural fitting gaps (such as the gap between the bottom ring 321 and the bottom pin 325) to safely release excessive gas pressure in the new fuel assembly transport container.

[0057] The bottom support block 324 can be installed on the base ring 321. Specifically, the bottom support block 324 and the bottom pin 325 can be made of wood, for example, pine. The other axial end of the bottom support block 324 ( Figure 7 The upper end of the bottom support block 324 can be provided with a positioning hole 32a, which can be a blind hole extending along the axial direction A. The bottom support block 324 can be provided from the other axial end of the bottom ring 321. Figure 7 The upper end of the bottom support block 324 is inserted into the bottom ring 321 and connected to the bottom ring 321 via a bottom pin 325. The bottom support block 324 can be located on the other axial side of the bottom insulation block 323. Figure 7 The upper side of the bottom support block 324, one axial end face ( Figure 7 The lower end face of the middle heat insulation block 323 and the other axial end face of the bottom heat insulation block 323 ( Figure 7 The upper surfaces of the two parts can be glued together.

[0058] Reference Figure 9 and Figure 10The heat insulation cover 33 may include a cover ring 331, a cover sealing plate 332, a hanging point shaft 333, a top heat insulation block 334, a top support block 335, a top pin 336, a ring body 337, a compensation pad 338, and a connecting plate.

[0059] The top insulation block 334 can be obtained by casting. Specifically, the cover ring 331, the cover plate 332, and the suspension shaft 333 can be made of stainless steel, for example, austenitic stainless steel. The cover ring 331 can be fitted onto the cover plate 332. The cover plate 332 can be located at the opposite axial end of the cover ring 331. Figure 9 The upper end of the lifting point shaft 333 is welded to the cover ring 331. The lifting point shaft 333 can penetrate the cover sealing plate 332 and is welded to it. The other axial end face of the lifting point shaft 333 ( Figure 9 The upper end face of the top heat insulation block 334 may be provided with a lifting hole, which may be a threaded hole extending along the axial direction A. The top heat insulation block 334 may include aluminum silicate composite fibers, which can be deposited by casting onto the other axial end of the cover ring 331. Figure 9 The upper end of the cover plate 332 can be located on the other side of the axial direction of the top heat insulation block 334. Figure 9 (The upper side of the middle). For example, in this embodiment, the top insulation block 334 and the cylinder insulation block 311 can be prepared from composite fiber castable with the same formulation.

[0060] The cover ring 331 can define the top vent 33a. Specifically, the other axial end of the cover ring 331 ( Figure 9 The upper end of the cover plate 322 can be provided with a notch, which can be formed as a top vent 33a. The top vent 33a and the cover plate 332 can be offset radially R, and the bottom of the top vent 33a can be aligned with the other end face of the cover plate 322 on the axial side. Figure 9 The upper surface of the inner enclosure 1 is flush with the outer enclosure 2, and multiple top exhaust ports 33a can be evenly arranged in the circumferential direction C. The cavity inside the inner enclosure 1 can communicate with the cavity inside the outer enclosure 2 through the top exhaust ports 33a, structural fitting gaps, etc. Under high-temperature conditions such as burning, the high-temperature pyrolysis gas of the non-metallic material inside the inner enclosure 1 can be discharged from the outer enclosure 2 through the top exhaust ports 33a, structural fitting gaps (such as the gap between the cover ring 331 and the top pin 336), etc., to safely release the excessive gas pressure in the new fuel assembly transport container.

[0061] The top support block 335 can be installed on the cover ring 331. Specifically, the top support block 335 and the top pin 336 can be made of wood, for example, pine. The top support block 335 can be installed from one axial end of the cover ring 331. Figure 9The upper end of the cover box ring 331 can be inserted into the ring body 337, and the ring body 337 can be pin-connected with the cover box ring 331 through the top pin 336. The top support block 335 can be arranged on the axial one side of the top heat insulation block 334 (the lower side in FIG. 10), and the axial one side end face of the top heat insulation block 334 (the lower end face in FIG. 10) and the axial other side end face of the top support block 335 (the upper end face in FIG. 10) can be bonded with each other. Figure 9 Figure 9 Figure 9

[0062] The ring body 337 can be mounted on the cover box ring 331. Specifically, the ring body 337 can be made of wood, for example, can be made of pine. The ring body 337 can be sleeved on the cover box ring 331 and bonded with the cover box ring 331. The axial other side end face of the ring body 337 (the upper end face in FIG. 10) can be flush with the upper end face of the cover box ring 331. The radial outer side of the ring body 337 can form an annular space for storing gas. Figure 9

[0063] The compensation pad 338 can be mounted on the top support block 335. Specifically, the connecting plate can be made of stainless steel, for example, can be made of austenitic stainless steel. The compensation pad 338 can be made of wood or rubber, for example, can be cork paper. The connecting plate and the compensation pad 338 can be arranged in the axial direction A, and the axial one side end face of the connecting plate (the lower end face in FIG. 10) and the axial other side end face of the compensation pad 338 (the upper end face in FIG. 10) can be bonded with each other. The compensation pad 338 and the connecting plate can be arranged on the axial one side of the top support block 335 (the lower side in FIG. 10), and the axial one side end face of the top support block 335 (the lower end face in FIG. 10) and the axial other side end face of the connecting plate (the upper end face in FIG. 10) can be bonded with each other. Figure 9 Figure 9 Figure 9 Figure 9 Figure 4

[0064] Referring to FIG. 10, Figure 4 The inner containment shell 1 and the outer containment shell 2 can be separated by the heat insulation structure 3. Specifically, the heat insulation bottom 32 can be arranged between the inner shell bottom plate 112 and the outer shell bottom plate 212. The axial one side end of the bottom box ring 321 (the right end in FIG. 10) can abut against the outer shell bottom plate 212, and the axial other side end of the bottom support block 324 (the left end in FIG. 10) can abut against the inner shell bottom plate 112. The heat insulation cover 33 can be arranged between the inner shell cover plate 113 and the end cover 213. The axial one side end of the compensation pad 338 (the right end in FIG. 10) can abut against the inner shell cover plate 113, and the axial other side end of the ring body 337 and the cover box ring 331 (the left end in FIG. 10) can abut against the end cover 213. Figure 4 Figure 4 Figure 4 Figure 4 ​​​​​​​​​​​​The left end of the inner shell 111 can abut against the end cap 213. The outer shell base plate 212 and the end cap 213 can clamp the inner shell 1, the heat insulation bottom 32 and the heat insulation cover 33 in the axial direction A, so that the inner shell 1 is limited in the axial direction A. The outer cylinder 211 can be sleeved on the heat insulation cylinder 31, the heat insulation bottom 32 and the heat insulation cover 33, and the heat insulation cylinder 31 can be sleeved on the inner cylinder 111, so that the inner shell 1 is limited in the radial direction R.

[0065] The casting process of the cylindrical insulation block 311 can be carried out during assembly. Specifically, before obtaining the cylindrical insulation block 311, the inner enclosure shell 1 and the insulation base 32 can be pre-installed inside the outer enclosure shell 2. The inner shell bottom plate 112 can be partially inserted into the positioning hole 32a, thereby achieving pre-positioning of the inner enclosure shell 1. After pre-positioning is completed, the outer circumferential surface of the inner cylinder 111 and the inner circumferential surface of the outer cylinder 211 can jointly define a cylindrical annular cavity, and the composite fiber castable of the cylindrical insulation block 311 can be directly injected into this cavity. Before the castable solidifies, the cylindrical support block 312 can be sleeved on the inner enclosure shell 1, and the other axial end of the inner enclosure shell 1 ( Figure 4 The left end of the inner cylinder 111 can abut against the step of the cylinder support block 312. The inner circumferential surface of the cylinder support block 312 can abut against the outer circumferential surface of the inner cylinder 111, and the outer circumferential surface of the cylinder support block 312 can abut against the inner circumferential surface of the outer cylinder 211, so that the cylinder support block 312 and the heat insulation base 32 can jointly support the inner enclosure shell 1 in the radial direction R. The upper end face of the castable (i.e., the face used to form the other axial end face of the cylinder heat insulation block 311) can be flattened, and the axial end face of the cylinder support block 312 ( Figure 4 The right end face of the inner shell can be bonded to the upper end face of the castable. After that, the castable is dried, so that the castable solidifies into a cylindrical heat insulation block 311. In this way, the inner shell 1, outer shell 2, heat insulation bottom 32 and other components can be cast into an integral structure that cannot be disassembled. The cylindrical heat insulation block 311, the cylindrical support block 312 and the heat insulation bottom 32 can jointly support the inner shell 1 in the radial direction R.

[0066] This application has at least the following advantages.

[0067] The thermal insulation structure 3 is suitable for installation in confined spaces. Specifically, the aluminum silicate composite fiber can be poured to fill the annular cavity between the inner enclosure shell 1 and the outer enclosure shell 2, eliminating the installation steps required for the thermal insulation structure 3 in confined spaces and effectively reducing the installation difficulty of the thermal insulation structure 3.

[0068] The thermal insulation structure 3 does not need to be designed with a large margin. Specifically, the castable of the aluminum silicate composite fiber can flow uniformly, so that the cast block can have good density uniformity and thermal insulation coefficient consistency, thereby facilitating accurate calculation of the thermal insulation performance of the thermal insulation structure 3. In the case of being able to accurately calculate the thermal insulation performance, the thickness of the thermal insulation structure 3 can be designed with a small margin, thereby realizing compact and accurate design.

[0069] The thermal insulation structure 3 can have a vibration damping and buffering function. Specifically, the aluminum silicate composite fiber and the wood both have a low thermal conductivity coefficient and good elastic performance (for example, compared to steel), so that the thermal insulation structure 3 can have good thermal insulation performance while having good vibration damping performance.

[0070] It should be understood that the above embodiments are only exemplary and are not intended to limit the present application. Those skilled in the art can make various modifications and changes to the above embodiments under the teaching of the present application without departing from the scope of the present application.

Claims

1. A heat-insulating structure of a new fuel assembly transport container including an inner containment vessel (1) for accommodating a new fuel assembly (4) and an outer containment vessel (2) for accommodating the inner containment vessel (1), the heat-insulating structure for partitioning the inner containment vessel (1) and the outer containment vessel (2), characterized in that, The heat insulation structure (3) comprises: a heat insulation cylinder (31) comprising a cylinder heat insulation block (311) comprising aluminum silicate composite fibers, the cylinder heat insulation block (311) being configured to be cast between the outer circumferential surface of the inner containment shell (1) and the inner circumferential surface of the outer containment shell (2); a heat insulation bottom (32) configured to be installed between the axial one-side end of the inner containment shell (1) and the axial one-side end of the outer containment shell (2), the heat insulation bottom (32) comprising a bottom heat insulation block (323) comprising aluminum silicate composite fibers and a bottom support block (324) comprising wood, the bottom heat insulation block (323) and the bottom support block (324) being arranged in a stacked manner in the axial direction (A) of the heat insulation bottom (32); and a heat insulation cover (33) configured to be installed between the axial other-side end of the inner containment shell (1) and the axial other-side end of the outer containment shell (2), the heat insulation cover (33) comprising a top heat insulation block (334) comprising aluminum silicate composite fibers and a top support block (335) comprising wood, the top heat insulation block (334) and the top support block (335) being arranged in a stacked manner in the axial direction (A) of the heat insulation cover (33), the heat insulation bottom (32) further comprising a bottom box ring (321), a bottom box sealing plate (322), and a bottom pin (325), the bottom box sealing plate (322) being arranged at the axial one-side end of the bottom box ring (321), the bottom box sealing plate (322) being fixedly connected with the bottom box ring (321), the bottom heat insulation block (323) being configured to be deposited at the axial one-side end of the bottom box ring (321) in a cast manner, the bottom box sealing plate (322) being located at the axial one-side of the bottom heat insulation block (323), the axial one-side end surface of the bottom support block (324) and the axial other-side end surface of the bottom heat insulation block (323) being bonded to each other, the bottom box ring (321) defining a bottom exhaust port (32c), the bottom exhaust port (32c) being a notch at the axial one-side end of the bottom box ring (321), the bottom box ring (321) being sleeved on the bottom box sealing plate (322), the bottom box sealing plate (322) and the bottom exhaust port (32c) being staggered with each other in the radial direction (R) of the bottom box ring (321), the inner cavity of the outer containment shell (2) being capable of being communicated with the cavity in the inner containment shell (1) via the bottom exhaust port (32c).

2. The thermally insulated structure according to claim 1, characterized in that the bottom pin (325) being made of wood, the bottom box ring (321) being sleeved on the bottom support block (324), the bottom box ring (321) and the bottom support block (324) being pin-connected with each other through the bottom pin (325).

3. The thermally insulated structure of claim 1, wherein The bottom box ring (321) defines an exhaust groove (32b) arranged on the outer circumferential surface of the bottom box ring (321) and extending along the circumferential direction (C) of the bottom box ring (321), and the inner cavity of the outer containment shell (2) can communicate with the cavity in the inner containment shell (1) through the exhaust groove (32b).

4. The thermally insulated structure of claim 1, wherein The bottom support block (324) defines a positioning hole (32a) arranged on the axially opposite end of the bottom support block (324), and the axially one side end of the inner containment shell (1) is configured to be inserted into the positioning hole (32a).

5. The thermally insulated structure of claim 1, wherein The heat insulation cover (33) further comprises a cover box ring (331), a cover box sealing plate (332), and a top pin (336), The cover box sealing plate (332) is arranged on the axially opposite end of the cover box ring (331), and the cover box sealing plate (332) is fixedly connected with the cover box ring (331). The top heat insulation block (334) is configured to be deposited on the axially opposite end of the cover box ring (331) in a pouring manner. The cover box sealing plate (332) is located on the axially opposite side of the top heat insulation block (334). The axially opposite end surface of the top support block (335) and the axially one side end surface of the top heat insulation block (334) are bonded to each other. The top pin (336) is made of wood. The cover box ring (331) is sleeved on the top support block (335), and the cover box ring (331) and the top support block (335) are pin-connected to each other through the top pin (336).

6. The thermally insulated structure according to claim 5, characterized in that The cover box ring (331) defines a top exhaust port (33a) which is a notch at the axially opposite end of the cover box ring (331). The cover box ring (331) is sleeved on the cover box sealing plate (332). The cover box sealing plate (332) and the top exhaust port (33a) are staggered with each other in the radial direction (R) of the cover box ring (331). The inner cavity of the outer containment shell (2) can communicate with the cavity in the inner containment shell (1) through the top exhaust port (33a).

7. The thermally insulated structure according to claim 5, characterized in that The heat insulation cover (33) further comprises a ring body (337), a compensation pad (338), and a connecting plate, The ring body (337) comprises wood. The ring body (337) is sleeved on the cover box ring (331), and the ring body (337) and the cover box ring (331) are bonded to each other. The axially opposite end of the ring body (337) is used for abutting against the outer containment shell (2). The radial outer side of the ring body (337) forms an annular space for storing gas. The compensation pad (338) is made of wood or rubber. The compensation pad (338) is bonded to the top support block (335) through the connecting plate. The axially one side end of the compensation pad (338) abuts against the inner containment shell (1).

8. The thermally insulated structure of claim 1, wherein The heat insulating cylinder (31) further includes a cylinder support block (312) made of wood, which is configured to be installed between the outer circumferential surface of the inner containment vessel (1) and the inner circumferential surface of the outer containment vessel (2).

9. A new fuel assembly transport container characterized by, Comprising: The heat insulating structure (3) according to any one of claims 1 to 8; The inner containment vessel (1); And The outer containment vessel (2).

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