Front thermal insulation shielding layer structure of horizontal gas-cooled reactor and horizontal gas-cooled reactor

Abstract

The present invention discloses a front thermal insulation shield structure for a horizontal gas-cooled reactor and a horizontal gas-cooled reactor including the front thermal insulation shield structure. The front thermal insulation shield structure comprises metal bricks, carbon bricks, and a locking mechanism. One end face of the metal brick is aligned with one end face of the carbon brick. A first through hole is provided in the center of the metal brick, and a second through hole is provided in the center of the carbon brick. The first through hole and the second through hole are connected to form a coolant channel, and the first and second through holes have the same diameter. The locking mechanism is used to connect and lock the metal brick and the carbon brick. The front thermal insulation shield structure can reduce the flow resistance of the coolant before it enters the reactor core.

Description

Technical Field

[0001] The present invention belongs to the technical field of nuclear industry, and in particular relates to a front thermal insulation shielding layer structure of a horizontal gas-cooled reactor and a horizontal gas-cooled reactor comprising the front thermal insulation shielding layer structure. Background Art

[0002] The prismatic high-temperature gas-cooled reactor (HTGR) is a type of fourth-generation nuclear reactor. Its core is primarily composed of graphite bricks and insulating carbon bricks. The core is arranged in a regular, prismatic shape. From the inside out, it comprises the fuel zone, upper and lower reflectors, side reflectors, upper and lower carbon brick layers, and side carbon brick layers. The reactor uses helium as its coolant, which flows from top to bottom through the upper carbon brick layer, upper reflector, core, lower reflector, and hot gas chamber. As it flows downward, the coolant gradually heats, cooling the core. The heated coolant then flows out of the reactor through the hot gas chamber.

[0003] All currently built prismatic high-temperature gas-cooled reactors are vertical structures. Before entering the core, the coolant is diverted by a layer of insulating carbon bricks, then flows through a graphite reflector layer before flowing into the core. The insulating carbon bricks in vertical prismatic reactors rely on gravity to naturally generate a vertical downward compression force, eliminating the need for connection to a dedicated compression structure. There are currently no reports on the insulating carbon bricks in horizontal prismatic high-temperature gas-cooled reactors.

[0004] In existing technology, the prismatic insulated carbon brick structure features multiple small coolant channels at one end, a larger cavity in the middle, and multiple smaller coolant channels at the other end. This structure causes the coolant to undergo sudden expansion and contraction as it flows through the insulated carbon brick structure, resulting in high flow resistance. This unstable flow increases fluid flow losses and causes uneven coolant flow immediately after entering the reflector layer and core.

[0005] At the same time, the existing insulating carbon brick structure has twenty coolant channels with a diameter of more than ten millimeters, but the insulating carbon brick material is hard, the processing process is time-consuming, and the tool wear is serious. Moreover, the existing insulating carbon brick structure does not establish an effective connection between the core and the axial metal clamping mechanism. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies in the prior art and provide a front thermal insulation shielding layer structure of a horizontal gas-cooled reactor and a horizontal gas-cooled reactor including the front thermal insulation shielding layer structure. The front thermal insulation shielding layer structure of the horizontal gas-cooled reactor can reduce the flow resistance of the coolant before it enters the core.

[0007] In order to solve the above problems, the present invention adopts the following technical solutions:

[0008] A front thermal insulation shielding layer structure of a horizontal gas-cooled reactor includes a metal brick, a carbon brick, and a locking mechanism. One end face of the metal brick is in contact with one end face of the carbon brick, and a first through hole is provided in the center of the metal brick, and a second through hole is provided in the center of the carbon brick. The first through hole is connected to the second through hole to form a coolant channel, and the diameters of the connection between the first through hole and the second through hole are the same. The locking mechanism is used to connect and lock the metal brick and the carbon brick.

[0009] Preferably, the locking mechanism includes a locking stud, a locking nut, and a disc spring washer. The metal brick is also provided with a groove, and the carbon brick is also provided with a third through hole. The opening of the groove is set at an end away from the carbon brick, and the groove corresponds to the position of the third through hole. The locking stud is passed through the third through hole, and its head end passes through the bottom of the metal brick into the groove. The locking nut is clamped in the groove and threadedly connected to the head end of the locking stud. The disc spring washer is sleeved on the locking stud, is in the groove, and is compressed between the bottom of the groove and the locking nut.

[0010] Preferably, the grooves are provided in plurality, and the plurality of grooves are respectively provided on a circumference centered on the first through hole, and the third through hole and the locking mechanism are also provided in corresponding plurality.

[0011] Preferably, the longitudinal cross-section of the third through hole is T-shaped, and the end thereof away from the metal brick is its head end. Accordingly, the tail end of the locking stud is located in the head end of the third through hole.

[0012] Preferably, a first inverted tooth is provided on the disc spring washer in contact with the locking nut, and a second inverted tooth is correspondingly provided on the locking nut.

[0013] Preferably, a third inverted tooth is provided on the disc spring gasket in contact with the groove, and a fourth inverted tooth is correspondingly provided on the groove.

[0014] Preferably, a boss is provided on the end of the first through hole away from the carbon brick.

[0015] Preferably, the metal bricks are made of stainless steel.

[0016] Preferably, the metal bricks and the carbon bricks are both prismatic.

[0017] The present invention also provides a horizontal gas-cooled reactor, comprising a core, a reflective layer, and the above-mentioned front thermal insulation shielding layer structure, wherein the core is arranged inside the reflective layer, and the reflective layer is arranged on the rear side of the front thermal insulation shielding layer structure, and the coolant flows into the reflective layer and the core through a first through hole and a second through hole.

[0018] The first through hole of the metal brick on the front thermal insulation shield structure of the horizontal gas-cooled reactor in the present invention is aligned with the second through hole on the carbon brick to form a coolant channel, and the diameter of the first through hole and the second through hole at the connection point are the same, so that the coolant can flow evenly in the coolant channel and reduce the resistance to flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a cross-sectional view of the thermal insulation shielding layer device of the horizontal gas-cooled reactor in Example 1 of the present invention;

[0020] Figure 2 1 is a schematic diagram of the three-dimensional structure of the thermal insulation shielding layer device of the horizontal gas-cooled reactor in Example 1 of the present invention;

[0021] Figure 3 It is a front view of the thermal insulation shielding layer device of the horizontal gas-cooled reactor in Example 1 of the present invention.

[0022] In the figure: 1-locking nut, 2-disc spring washer, 3-metal brick, 4-locking stud, 5-carbon brick, 6-first through hole, 7-second through hole, 8-third through hole, 9-groove, 10-boss. DETAILED DESCRIPTION

[0023] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of the present invention.

[0024] In the description of the present invention, it should be noted that the term "upper" and the like to indicate an orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience and simplification of the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0025] In the description of the present invention, the terms “first” and “second” are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0026] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "connect," "dispose," "install," "fix," etc. should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integral connection; they may refer to direct connection, indirect connection through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0027] The present invention provides a front thermal insulation shielding layer structure of a horizontal gas-cooled reactor, comprising a metal brick, a carbon brick, and a locking mechanism. One end face of the metal brick is in contact with one end face of the carbon brick, and a first through hole is provided in the center of the metal brick, and a second through hole is provided in the center of the carbon brick. The first through hole is connected to the second through hole to form a coolant channel, and the diameters of the first through hole and the second through hole are the same. The locking mechanism is used to connect and lock the metal brick and the carbon brick.

[0028] The present invention also provides a horizontal gas-cooled reactor, comprising a core, a reflective layer, and the above-mentioned front thermal insulation shielding layer structure, wherein the core is arranged inside the reflective layer, and the reflective layer is arranged inside the front thermal insulation shielding layer structure, and the coolant flows into the reflective layer and the core through a first through hole and a second through hole.

[0029] Example 1

[0030] like Figure 1 As shown, this embodiment discloses a front thermal insulation shielding layer structure of a horizontal gas-cooled reactor, including metal bricks 3, carbon bricks 5, and a locking mechanism. In this embodiment, the metal bricks 3 and the carbon bricks 5 are both prismatic structures. Specifically, their cross-sections are both regular hexagons, and their sizes are the same.

[0031] One end face of the metal brick 3 is fitted with one end face of the carbon brick 5, and a first through hole 6 is provided in the center of the metal brick 3, and a second through hole 7 is provided in the center of the carbon brick 5. The first through hole 6 is connected to the second through hole 7 to form a coolant channel, and the diameters of the connection between the first through hole 6 and the second through hole 7 are the same. The locking mechanism is used to connect and lock the metal brick 3 and the carbon brick 5.

[0032] Specifically, the metal brick 3 is made of stainless steel, and the specific model is 316H.

[0033] like Figure 1 As shown, specifically, the first through hole 6 is divided into three interconnected sections along its axial direction, namely a cylindrical hole (second section) in the middle and two trumpet-shaped holes at both ends. The small diameter ends of the two trumpet-shaped holes in the first and third sections have the same diameter as the straight hole. The second through hole 7 is a cylindrical hole. The large diameter end of the trumpet-shaped hole in the third section has the same diameter as the second through hole 7, and the large diameter end of the trumpet-shaped hole in the third section is connected to and connected with one end of the second through hole 7. The structural design of the first through hole 6 allows the coolant to have a converging effect when entering the first through hole 6 and a diffusing effect when flowing out of the first through hole 6, so that the coolant can be evenly distributed in the second channel. The diameters of the various sections of the first through hole 6 are different. This arrangement is to facilitate the gripper (a tool used during fuel replacement) to reach into the first through hole 6 for gripping.

[0034] In this embodiment, the locking mechanism includes a locking stud 4, a locking nut 1, and a disc spring washer 2. A groove 9 is also provided on the metal brick 3, and a third through hole 8 is also provided on the carbon brick 5. The opening of the groove 9 is set at the end away from the carbon brick 5, and the groove 9 corresponds to the position where the third through hole 8 is connected. The locking stud 4 is passed through the third through hole 8, and its head end passes through the bottom of the metal brick 3 (the side close to the carbon brick 5) and enters the groove 9. The outer diameter of the locking nut 1 is the same as the diameter of the groove 9. The locking nut 1 is clamped in the groove 9 and threadedly connected to the head end of the locking stud 4. The disc spring washer 2 is sleeved on the locking stud 4, which is in the groove 9 and is compressed between the bottom of the groove 9 and the locking nut 1 to improve the connection strength between the metal brick 3 and the carbon brick 5.

[0035] Due to the significant difference in expansion coefficients between metal and carbon materials, at high temperatures, the locking bolts elongate due to heat, loosening the connection between the metal brick 3 and the carbon brick 5. This can create gaps at the interface, leading to coolant leakage and reduced coolant flow through the metal bricks 3 and 5. However, the disc spring gasket 2 is in a compressed state during the initial connection between the metal brick 3 and the carbon brick 5. When the high temperature causes the locking bolts to elongate, the compressed disc spring gasket 2 releases its elastic potential energy, absorbing the elongation deformation of the locking bolts. The remaining elastic potential energy still maintains a tight connection between the metal brick 3 and the carbon brick 5.

[0036] In this embodiment, the groove 9 is provided with a plurality of grooves, such as Figure 2 、 3 As shown, specifically, there are three grooves 9, which are respectively on the circumference centered on the first through hole 6, with a central angle of 120° between two adjacent grooves 9, and there are also three corresponding third through holes 8 and locking mechanisms.

[0037] like Figure 1 As shown, the longitudinal cross-section of the third through hole 8 is T-shaped, and the end away from the metal brick 3 is its head end. Correspondingly, the longitudinal cross-section of the locking stud 4 is also T-shaped, and the tail end of the locking stud 4 is in the head end of the third through hole 8. Specifically, the tail end of the locking stud 4 is overlapped or clamped on the head end of the third through hole 8.

[0038] Optionally, a first inverted tooth is provided on the disc spring washer 2 in contact with the locking nut 1, and a second inverted tooth is correspondingly provided on the locking nut 1, that is, the first inverted tooth and the second inverted tooth are respectively provided on the contact surface of the disc spring washer 2 and the locking nut 1, for preventing the disc spring washer 2 and the locking nut 1 from loosening.

[0039] Optionally, a third inverted tooth is provided on the disc spring gasket 2 in contact with the groove 9, a fourth inverted tooth is correspondingly provided on the groove 9, and a third inverted tooth is provided on the outer periphery of the disc spring gasket 2, and a fourth inverted tooth is provided on the inner wall of the groove 9. The third inverted tooth cooperates with the fourth inverted tooth to prevent the disc spring gasket 2 from rotating in the groove 9.

[0040] In this embodiment, a boss 10 is provided on the end of the first through hole 6 away from the carbon brick 5 for positioning and connecting with other components in the reactor and serving as a positioning interface for the refueling mechanism to grab the carbon brick 5 during refueling.

[0041] Compared to the prior art method of forming several small holes in the carbon brick 5, the first through-holes 6 of the metal brick 3 in the front thermal shield structure of this embodiment align with the second through-holes 7 of the carbon brick 5 to form a coolant channel. The first through-holes 6 and the second through-holes 7 have the same diameter, ensuring uniform coolant flow within the channel, thereby reducing flow resistance. Furthermore, compared to existing carbon brick 5 structures, the carbon brick 5 in this structure only has a very small number of holes. This significantly improves processing efficiency for high-hardness carbon bricks 5, reduces tool wear, and saves costs. Furthermore, a locking mechanism ensures a tight connection between the metal brick 3 and the carbon brick 5 even at high temperatures.

[0042] Example 2

[0043] This embodiment discloses a horizontal gas-cooled reactor, including a core, a reflective layer, and the front thermal insulation shielding layer structure of Example 1. The core is arranged inside the reflective layer, and the reflective layer is arranged inside the front thermal insulation shielding layer structure. The coolant flows into the reflective layer and the core through the first through hole 6 and the second through hole 7.

[0044] The coolant in the horizontal gas-cooled reactor in this embodiment flows evenly into the interior of the reactor core through the front thermal insulation shielding layer structure, and has low flow resistance, thereby being able to efficiently cool the interior of the reactor core.

[0045] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A front thermal insulation shielding layer structure of a horizontal gas-cooled reactor, characterized in that: It includes metal bricks (3), carbon bricks (5), and a locking mechanism. One end face of the metal brick (3) is fitted with one end face of the carbon brick (5), and a first through hole (6) is provided at the center of the metal brick (3), and a second through hole (7) is provided at the center of the carbon brick (5), the first through hole (6) and the second through hole (7) are connected to form a coolant channel, and the diameter of the connection between the first through hole (6) and the second through hole (7) is the same, The locking mechanism is used to connect and lock the metal brick (3) and the carbon brick (5).

2. The front thermal insulation shielding layer structure of a horizontal gas-cooled reactor according to claim 1, characterized in that: The locking mechanism comprises a locking stud (4), a locking nut (1), and a disc spring washer (2). The metal brick (3) is further provided with a groove (9), and the carbon brick (5) is further provided with a third through hole (8). The opening of the groove (9) is arranged at an end away from the carbon brick (5), and the position of the groove (9) corresponds to that of the third through hole (8). The locking stud (4) is inserted into the third through hole (8), and its head end passes through the bottom of the metal brick (3) and enters the groove (9). The locking nut (1) is clamped in the groove (9) and is threadedly connected to the head end of the locking stud (4). The disc spring washer (2) is sleeved on the locking stud, is located in the groove (9), and is compressed between the bottom of the groove (9) and the locking nut (1).

3. The front thermal insulation shielding layer structure of a horizontal gas-cooled reactor according to claim 2, characterized in that: There are multiple grooves (9), and the multiple grooves (9) are respectively on the circumference of the first through hole (6) as the center. The third through hole (8) and the locking mechanism are also provided with a corresponding plurality.

4. The front thermal insulation shielding layer structure of a horizontal gas-cooled reactor according to claim 2, characterized in that: The longitudinal cross-section of the third through hole (8) is T-shaped, and the end away from the metal brick (3) is its head end. Correspondingly, the tail end of the locking stud (4) is located in the head end of the third through hole (8).

5. The front thermal insulation shielding layer structure of a horizontal gas-cooled reactor according to claim 2, characterized in that: A first inverted tooth is provided on the disc spring washer (2) in contact with the locking nut (1), and a second inverted tooth is correspondingly provided on the locking nut (1).

6. The front thermal insulation shielding layer structure of a horizontal gas-cooled reactor according to claim 5, characterized in that: A third inverted tooth is provided on the disc spring washer (2) in contact with the groove (9), and a fourth inverted tooth is correspondingly provided on the groove (9).

7. The front thermal insulation shielding layer structure of a horizontal gas-cooled reactor according to claim 1, characterized in that: A boss (10) is provided on one end of the first through hole (6) away from the carbon brick (5).

8. The front thermal insulation shielding layer structure of a horizontal gas-cooled reactor according to any one of claims 1 to 7, characterized in that: The metal bricks (3) are made of stainless steel.

9. The front thermal insulation shielding layer structure of a horizontal gas-cooled reactor according to any one of claims 1 to 7, characterized in that: The metal bricks (3) and the carbon bricks (5) are both prismatic.

10. A horizontal gas-cooled reactor comprising a core and a reflector layer, characterized in that: It also includes the front heat insulation shielding layer structure according to any one of claims 1 to 9, The core is arranged inside the reflective layer, and the reflective layer is arranged on the rear side of the front heat insulation shielding layer structure. The coolant flows into the reflective layer and the core through the first through hole (6) and the second through hole (7).

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