A horizontal core reactivity control device and a horizontal reactor

Abstract

The present invention discloses a horizontal core reactivity control device and a horizontal reactor including the horizontal core reactivity control device. The horizontal core reactivity control device includes a control rod and a driving mechanism. The driving assembly is used for linear stepping motion. The driven assembly includes a driven block, a rotating driving head, and a driving sleeve. The driven block is connected to the output end of the driving assembly. One end of the rotating driving head is rotatably connected to the driven block, and the other end is fixedly connected to the control rod. An external thread is provided on the outer surface of the rotating driving head, and an internal thread matching the external thread of the rotating driving head is provided on the inner surface of the driving sleeve. The driving assembly drives the driven block to perform linear stepping motion, so that the rotating driving head drives the control rod to perform linear stepping motion and rotational motion in the driving sleeve at the same time. In the horizontal core reactivity control device, the control rod has a small deflection during use, which can effectively ensure its insertability in the control rod channel.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear industry, and in particular relates to a horizontal core reactivity control device and a horizontal reactor comprising the horizontal core reactivity control device. Background Art

[0002] A high temperature gas-cooled reactor (HTGR) is a type of nuclear reactor that commonly uses a vertical core and a horizontal core. The vertical core is relatively high, which is not conducive to layout, while the horizontal core is relatively low, which is convenient for layout and can also meet the design requirements of a movable reactor.

[0003] The control rod is one of the important components for controlling the reactivity of the core, and its design must ensure that it has passive inherent safety. For the transverse insertion control rods used in the horizontal core, due to the effect of gravity, the control rods will produce deflection during long-term service, making it difficult to insert them into the core, which has a great impact on the safety of the reactor. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a horizontal core reactivity control device and a horizontal reactor including the horizontal core reactivity control device in view of the above-mentioned deficiencies in the prior art. The control rods in the horizontal core reactivity control device have a small deflection during use, which can effectively ensure their insertability in the control rod channel.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A horizontal core reactivity control device comprises a control rod and a driving mechanism, wherein the driving mechanism is used to drive the control rod to move, and comprises a driving assembly and a driven assembly, wherein the driving assembly is used to perform linear stepping motion, and the driven assembly comprises a driven block, a rotating driving head, and a driving sleeve, wherein the driven block is connected to the output end of the driving assembly, one end of the rotating driving head is rotationally connected to the driven block, and the other end is fixedly connected to the control rod, an external thread is provided on the outer surface of the rotating driving head, the driving sleeve is arranged along the horizontal direction, the rotating driving head and the control rod are both arranged in the driving sleeve, and an internal thread matched with the external thread on the rotating driving head is provided on the inner surface of the driving sleeve, the driving assembly drives the driven block to perform linear stepping motion, so that the rotating driving head drives the control rod to perform linear stepping motion and rotational motion in the driving sleeve at the same time.

[0007] Preferably, the drive assembly includes a motor and a screw unit, the screw unit includes a transmission rod and a drive block, the output end of the motor is connected to one end of the transmission rod, the axial direction of the transmission rod is parallel to the axial direction of the drive sleeve, the drive block is threadedly connected to the transmission rod, and the driven block is fixedly connected to the drive block.

[0008] Preferably, the rotary drive head is connected to the driven block via a bearing.

[0009] Preferably, the horizontal core reactivity control device also includes a transmission assembly, the transmission assembly includes a permanent magnet transmission unit, the permanent magnet transmission unit is fixedly connected to the drive block, one end of the drive sleeve is passed through the inner hole of the permanent magnet transmission unit, and the driven block is also arranged in the drive sleeve and is in the inner hole of the permanent magnet transmission unit.

[0010] Preferably, the horizontal core reactivity control device also includes a fixing assembly, which includes a first fixing plate and a second fixing plate, the first fixing plate and the second fixing plate are arranged in parallel, and the plate surfaces of the first fixing plate and the second fixing plate are perpendicular to the axial direction of the drive sleeve, the first fixing plate and the second fixing plate respectively support the two ends of the transmission rod, the motor and the drive block are respectively arranged on both sides of the first fixing plate, and the output end of the motor passes through the first fixing plate and is connected to the transmission rod; the two ends of the drive sleeve are respectively fixed on the first fixing plate and the second fixing plate.

[0011] Preferably, the horizontal core reactivity control device further comprises a measuring mechanism, which is disposed on the first fixed plate and is used to measure the distance moved by the driving block on the transmission rod.

[0012] The present invention also provides a horizontal reactor for a gas-cooled reactor, comprising a reactor core and the above-mentioned horizontal reactor core reactivity control device.

[0013] Preferably, a control rod channel is provided on the core, and the inner surface of the control rod channel is wavy or arched.

[0014] Preferably, the control rod channel includes a front channel and a rear channel, the front channel is multi-stage, the multi-stage front channels are connected in sequence, and the aperture of the front channel of the previous stage is smaller than the aperture of the front channel of the adjacent rear stage.

[0015] Preferably, the front channel of each level includes three sections connected to each other, namely, a first channel located in the middle, and a second channel and a third channel located on both sides of the first channel respectively, the first channel is cylindrical, and the first channel of the front channel of the previous level is smaller than the first channel of the front channel of the adjacent next level, the second channel and the third channel have the same shape and size, and both are trumpet-shaped, the third channel of the front channel of the previous level has the same shape and size as the second channel of the front channel of the next level, and the two are connected, the rear channel is a blind hole channel, and the opening of the rear channel has the same shape and size as the third channel of the front channel of the last level, and the two are connected.

[0016] The control rod in the horizontal core reactivity control device of the present invention is fixedly connected to the rotary drive head, and the rotary drive head is provided with an external thread, and the inner wall of the drive sleeve is provided with an internal thread matching the external thread. When the driving mechanism drives the rotary drive head to move linearly, the rotary drive head simultaneously performs a rotational motion, thereby driving the control rod to continuously rotate during the process of inserting the control rod into the control rod channel, thereby reducing the deflection of the control rod in a single direction under the action of gravity. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of a horizontal reactor control device in Example 1 of the present invention;

[0018] Figure 2 It is a schematic structural diagram of the driving mechanism, the fixing assembly, and the transmission mechanism in Example 1 of the present invention;

[0019] Figure 3 is an enlarged view of the transmission mechanism in Example 1 of the present invention;

[0020] Figure 4 is a schematic diagram of the mechanism of the insertion assembly in Embodiment 1 of the present invention;

[0021] Figure 5 The process of inserting the control rod into the hole in Example 1 of the present invention is shown in FIG. Figure 1 ;

[0022] Figure 6 The process of inserting the control rod into the hole in Example 1 of the present invention is shown in FIG. Figure 2 .

[0023] In the figure: 1-motor, 2-first fixed plate, 3-second fixed plate, 4-driving block, 5-driven block, 6-transmission rod, 7-bearing, 8-rotating driving head, 9-driving sleeve, 10-control rod, 11-front channel, 12-rear channel. DETAILED DESCRIPTION

[0024] The following will be combined with the accompanying drawings in the present invention to clearly and completely describe the technical solutions in the invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of the present invention.

[0025] In the description of the present invention, it should be noted that the term "upper" and the like to indicate 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 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 should not be understood as a limitation on the present invention.

[0026] 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.

[0027] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connect", "set", "install", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] The present invention provides a horizontal core reactivity control device, comprising a control rod and a driving mechanism. The driving mechanism is used to drive the control rod to move, and comprises a driving assembly and a driven assembly. The driving assembly is used to perform linear stepping motion. The driven assembly comprises a driven block, a rotating driving head, and a driving sleeve. The driven block is connected to the output end of the driving assembly. One end of the rotating driving head is rotatably connected to the driven block, and the other end is fixedly connected to the control rod. An external thread is provided on the outer surface of the rotating driving head. The driving sleeve is arranged along the horizontal direction. The rotating driving head and the control rod are both arranged in the driving sleeve. An internal thread matched with the external thread on the rotating driving head is provided on the inner surface of the driving sleeve. The driving assembly drives the driven block to perform linear stepping motion, so that the rotating driving head drives the control rod to perform linear stepping motion and rotational motion in the driving sleeve at the same time.

[0029] The present invention also provides a horizontal reactor for a gas-cooled reactor, comprising a reactor core and the above-mentioned horizontal reactor core reactivity control device.

[0030] Example 1

[0031] like Figure 2As shown, this embodiment discloses a horizontal core reactivity control device, including a control rod 10 and a driving mechanism, the driving mechanism is used to drive the control rod 10 to move, and includes a driving assembly and a driven assembly, the driving assembly is used to perform linear stepping motion, the driven assembly includes a driven block 5, a rotating driving head 8, and a driving sleeve 9, the driven block 5 is connected to the output end of the driving assembly, one end of the rotating driving head 8 is rotatably connected to the driven block 5, and the other end is fixedly connected to the control rod 10, an external thread is provided on the outer surface of the rotating driving head 8, the driving sleeve 9 is arranged along the horizontal direction, the rotating driving head 8 and the control rod 10 are both arranged in the driving sleeve 9, and an internal thread matched with the external thread on the rotating driving head 8 is provided on the inner surface of the driving sleeve 9, wherein the rotating driving head 8 and the control rod 10 have the same diameter, and the inner diameter of the driving sleeve 9 is slightly larger than the diameter of the rotating driving head 8 and the control rod 10, so that a certain gap is left between the rotating driving head 8 and the driving sleeve 9. The driving assembly drives the driven block 5 to perform linear stepping motion, so that the rotary driving head 8 drives the control rod 10 to perform linear stepping motion and rotational motion in the driving sleeve 9 at the same time.

[0032] like Figure 3 As shown, the drive assembly includes a motor 1 and a screw unit, the screw unit includes a transmission rod 6 and a drive block 4, the output end of the motor 1 is connected to one end of the transmission rod 6, the axial direction of the transmission rod 6 is parallel to the axial direction of the drive sleeve 9, the through hole of the drive block 4 is provided with an internal thread, the transmission rod 6 is provided with a corresponding external thread, the drive block 4 is threadedly connected to the transmission rod 6, and is used to control and ensure the accuracy of the step, and the driven block 5 is fixedly connected to the drive block 4. The motor 1 drives the transmission rod 6 to rotate, thereby driving the drive block 4 to make a linear motion along the axial direction of the transmission rod 6, and transmits power to the driven block 5, thereby driving the driven block 5 to make a linear motion along the axial direction of the drive sleeve 9.

[0033] like Figure 2 As shown, specifically, a groove is provided at one end of the driven block 5 close to the rotary drive head 8, a bearing 7 is provided in the groove, and the rotary drive head 8 is connected to the driven block 5 via the bearing 7, so that the rotary drive head 8 rotates around the bearing 7, and the driven block 5 only needs to make a linear motion along the axial direction of the drive sleeve 9.

[0034] In this embodiment, the horizontal core reactivity control device also includes a transmission assembly, which includes a permanent magnet transmission unit, which is fixedly connected to the driving block 4. One end of the driving sleeve 9 is inserted into the inner hole of the permanent magnet transmission unit. The driven block 5 is also arranged in the driving sleeve 9 and is in the inner hole of the permanent magnet transmission unit. The driven block 5 is connected to the permanent magnet transmission unit through magnetic force, so that it follows the driving block 4 to make a linear motion along the axial direction of the driving sleeve 9 under the action of the driving mechanism.

[0035] like Figure 2As shown, the horizontal core reactivity control device also includes a fixing assembly, which includes a first fixing plate 2 and a second fixing plate 3. The first fixing plate 2 and the second fixing plate 3 are arranged in parallel and spaced at a certain distance (the spacing distance is the same as the length of the transmission rod 6), and the plate surfaces of the first fixing plate 2 and the second fixing plate 3 are perpendicular to the axial direction of the driving sleeve 9. The first fixing plate 2 and the second fixing plate 3 support the two ends of the transmission rod 6 respectively, and the motor 1 and the driving block 4 are arranged on both sides of the first fixing plate 2. Specifically, the motor 1 is arranged on the side of the first fixing plate 2 away from the second fixing plate 3, and the driving block 4 is arranged between the first fixing plate 2 and the second fixing plate 3. The output end of the motor 1 passes through the first fixing plate 2 and is connected to the transmission rod 6; the two ends of the driving sleeve 9 are respectively fixed on the first fixing plate 2 and the second fixing plate 3, and one end of the driving sleeve 9 passes through the second fixing plate 3 and extends outward.

[0036] Optionally, the horizontal core reactivity control device further comprises a measuring mechanism, which is disposed on the first fixed plate 2 and is used to measure the distance the driving block 4 moves on the transmission rod 6. By measuring the moving distance of the driving block 4 by the measuring mechanism, the position of the control rod 10 can be determined.

[0037] When it is necessary to adjust the depth of the control rod 10 inserted into the core, the motor 1 drives the driving block 4 to perform linear stepping motion on the transmission rod 6, and at the same time, the stepping distance of the driving block 4 is measured by the measuring mechanism to serve as data for determining the position of the control rod 10. Under the action of magnetic force, the linear stepping of the driving block 4 drives the driven block 5 to perform linear stepping motion in the driving sleeve 9, thereby generating thrust or drag force on the rotary driving head 8. Since the rotary driving head 8 is provided with an external thread and cooperates with the internal thread of the driving sleeve 9, under the action of the axial force, the external thread on the rotary driving head 8 moves in the screw groove of the internal thread of the driving sleeve 9, thereby performing rotational motion relative to the driving sleeve 9, and is accompanied by linear stepping motion along the axial direction of the driving sleeve 9. In addition, since the rotary driving head 8 is connected to the driven block 5 through the bearing 7, the rotation of the rotary driving head 8 will not drive the driven block 5 to rotate, thereby avoiding the generation of additional driving force consumption. Since the control rod 10 is fixedly connected to the rotary drive head 8 , the movement of the control rod 10 is consistent with the movement of the rotary drive head 8 , that is, the control rod 10 performs a linear stepping motion along the axial direction of the drive sleeve 9 accompanied by a rotary motion.

[0038] In the prior art, control rods in a horizontal core are generally inserted horizontally. During the insertion process, the control rods will bend due to the influence of gravity. In addition, due to the long length of the control rods, a large deflection will be generated in a single direction (vertically downward) at the end of the control rods, thereby affecting the insertion or extraction of the control rods into the control rod channel, and further affecting the safety of the reactor.

[0039] The horizontal core reactivity control device in this embodiment can make the control rod 10 rotate while stepping, thereby preventing the control rod 10 from being subjected to large single-direction deflection due to gravity, and allowing the control rod 10 to compensate for the deflection by itself during the stepping process, thereby reducing its total deflection.

[0040] Example 2

[0041] like Figure 1 As shown, this embodiment discloses a horizontal reactor for a gas-cooled reactor, including a core and the horizontal core reactivity control device in Embodiment 1.

[0042] like Figure 4 As shown, a control rod channel is provided on the core, and the inner surface of the control rod channel is wavy or arched.

[0043] In this embodiment, the control rod channel includes a front channel 11 and a rear channel 12. The front channel 11 is multi-stage, and the multi-stage front channels 11 are sequentially connected, and the aperture of the front channel 11 of the previous stage is smaller than the aperture of the front channel 11 of the adjacent rear stage. The inner edges of the front channel 11 and the rear channel 12 are continuous, and it should be ensured that the end of the control rod 10 after assembly is always partially in the front channel 11 or the rear channel 12.

[0044] Specifically, the front channel 11 of each stage includes three sections connected to each other, namely, the first channel located in the middle, and the second channel and the third channel located on both sides of the first channel, the first channel is cylindrical, and the first channel of the front channel 11 of the previous stage is smaller than the first channel of the front channel 11 of the adjacent next stage, the second channel and the third channel have the same shape and size, and both are trumpet-shaped, the third channel of the front channel 11 of the previous stage has the same shape and size as the second channel of the front channel 11 of the next stage, and the two are connected, and the two ends of the first channel of the front channel 11 of each stage are respectively connected to the small diameter ends of the second channel and the third channel at both ends, and the large diameter end of the third channel of the front channel 11 of the previous stage is connected to the large diameter end of the second channel of the front channel 11 of the next stage. The rear channel 12 is a blind hole channel, and the opening of the rear channel 12 has the same shape and size as the third channel of the front channel 11 of the last stage, and the two are connected.

[0045] like Figure 5 , 6 As shown in FIG. 1 , after the control rod 10 is inserted into the control rod channel, it will bend under the action of gravity, as shown in FIG. Figure 5As shown (for the purpose of explanation, the dimensions in the figure are exaggerated to a certain extent), the first hole (the smallest inner diameter) of the front channel 11 of each stage can limit the maximum deflection of the control rod 10, and the corrugated connection of the front channel 11 of each stage can make the end of the control rod 10 play a better guiding role during the insertion and withdrawal process to avoid jamming.

[0046] In addition to the gravity factor, the temperature factor will also affect the deflection of the control rod 10. When the control rod 10 is at a temperature exceeding the design reference, a greater deflection may occur (e.g. Figure 5 At this time, due to the design of gradually increasing the inner diameter of the first channel of each stage of the front channel 11 in the control device of this embodiment, more support can be provided for the further bending control rod 10 (as shown in the dashed line part). Figure 5 The control rod 10 has good and acceptable structural integrity, which makes it easy to insert and remove the control rod channel and ensure the safety of the core.

[0047] based on Figure 5 The state of the control rod 10 in the stepping continues (the control rod 10 is in the solid line state). The control rod 10 after the stepping is as follows Figure 6 As shown in the figure, the solid line is the state of the control rod 10 just after the step. Since the step is accompanied by rotation, the deflection of the control rod 10 changes to the opposite direction of the gravity. After that, with the creep effect of the structural material of the control rod 10, the control rod 10 tends to Figure 6 The dotted line state in the figure develops, thereby achieving the effect of correcting the deflection of the control rod 10.

[0048] Under normal reactor operation, the ambient temperature of the horizontal reactor control rod may reach 700°C, and under accident conditions, the working environment of the horizontal reactor control rod may reach above 1000°C. Therefore, in this embodiment, all metal structural materials in the horizontal reactor control rod are made of high-temperature resistant nickel-based alloy. In addition, to prevent the metal contact surface materials from biting and sticking to each other under high temperature environment, adjacent metal contact surfaces are treated with solid lubricants, wherein the material of the solid lubricant is selected from different grades according to the properties of the adjacent metals to maintain the flexibility of each sliding mating surface.

[0049] The horizontal reactor in this embodiment adopts the horizontal core reactivity control device in Example 1. The driving mechanism provides axial propulsion power and rotational driving force for the control rod, which can make the control rod rotate while stepping, thereby achieving the effect of compensating and reducing deflection. The wavy structure of the inner wall of the control rod channel limits the maximum deflection of the control rod when it stays in a certain position for a long time, and on the other hand, avoids the phenomenon of the control rod being stuck at the connection with the front channels 11 of each level during insertion and withdrawal, making the insertion and withdrawal of the control rod smoother and enhancing the insertability of the control rod of the horizontal gas-cooled micro-reactor into the control rod channel. In addition, the horizontal reactor has a long service life, simple operation and high safety.

[0050] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A horizontal core reactivity control device, characterized in that: It comprises a control rod (10) and a driving mechanism, The driving mechanism is used to drive the control rod (10) to move, and comprises a driving component and a driven component. The driving assembly is used for linear stepping motion. The driven assembly comprises a driven block (5), a rotary drive head (8), and a drive sleeve (9); the driven block (5) is connected to the output end of the drive assembly; one end of the rotary drive head (8) is rotatably connected to the driven block (5) and the other end is fixedly connected to the control rod (10); an external thread is provided on the outer surface of the rotary drive head (8); The driving sleeve (9) is arranged in the horizontal direction, the rotating driving head (8) and the control rod (10) are both arranged in the driving sleeve (9), and the inner surface of the driving sleeve (9) is provided with an internal thread matched with the external thread on the rotating driving head (8). The driving assembly drives the driven block (5) to perform linear stepping motion, so that the rotary driving head (8) drives the control rod (10) to perform linear stepping motion and rotational motion in the driving sleeve (9) at the same time, so as to avoid the control rod from having a large vertical deflection due to gravity.

2. The horizontal core reactivity control device according to claim 1, characterized in that: The drive assembly comprises a motor (1) and a screw unit, wherein the screw unit comprises a transmission rod (6) and a drive block (4). The output end of the motor (1) is connected to one end of the transmission rod (6), the axial direction of the transmission rod (6) is parallel to the axial direction of the drive sleeve (9), the drive block (4) is threadedly connected to the transmission rod (6), and the driven block (5) is fixedly connected to the drive block (4).

3. The horizontal core reactivity control device according to claim 2, characterized in that: The rotary drive head (8) is connected to the driven block (5) via a bearing (7).

4. The horizontal core reactivity control device according to claim 2, characterized in that: It also includes a transmission assembly, wherein the transmission assembly includes a permanent magnet transmission unit, The permanent magnetic transmission unit is fixedly connected to the driving block (4), and one end of the driving sleeve (9) is inserted into the inner hole of the permanent magnetic transmission unit. The driven block (5) is also arranged in the driving sleeve (9) and is located in the inner hole of the permanent magnet transmission unit.

5. The horizontal core reactivity control device according to claim 2, characterized in that: It also includes a fixing assembly, the fixing assembly including a first fixing plate (2) and a second fixing plate (3), The first fixing plate (2) and the second fixing plate (3) are arranged in parallel, and the plate surfaces of the first fixing plate (2) and the second fixing plate (3) are perpendicular to the axial direction of the driving sleeve (9), and the first fixing plate (2) and the second fixing plate (3) respectively support two ends of the transmission rod (6). The motor (1) and the driving block (4) are arranged on both sides of the first fixing plate (2), and the output end of the motor (1) passes through the first fixing plate (2) and is connected to the transmission rod (6); Two ends of the driving sleeve (9) are respectively fixed on the first fixing plate (2) and the second fixing plate (3).

6. The horizontal core reactivity control device according to claim 5, characterized in that: It also includes measuring mechanisms, The measuring mechanism is arranged on the first fixing plate (2) and is used to measure the distance moved by the driving block (4) on the transmission rod (6).

7. A horizontal reactor for a gas-cooled reactor, characterized in that: It comprises a core and a horizontal core reactivity control device as described in any one of claims 1 to 6.

8. The horizontal reactor according to claim 7, characterized in that: The core is provided with a control rod channel, and the inner surface of the control rod channel is wavy or arched.

9. The horizontal reactor according to claim 8, characterized in that: The control rod channel comprises a front channel (11) and a rear channel (12), The front channel (11) is multi-stage, the multi-stage front channels (11) are connected in sequence, and the aperture of the front channel (11) of the previous stage is smaller than the aperture of the front channel (11) of the adjacent next stage.

10. The horizontal reactor according to claim 9, characterized in that: The front channel (11) of each stage comprises three sections which are interconnected, namely a first channel located in the middle, and a second channel and a third channel located on both sides of the first channel respectively. The first channel is cylindrical, and the first channel of the front channel (11) of the previous stage is smaller than the first channel of the front channel (11) of the adjacent next stage. The second hole and the third hole have the same shape and size, and both are trumpet-shaped; the third hole of the front channel (11) of the previous stage and the second hole of the front channel (11) of the next stage have the same shape and size, and the two are connected; The rear channel (12) is a blind hole channel, and the opening of the rear channel (12) has the same shape and size as the third channel of the last stage front channel (11), and the two are connected.

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