A test piece clamping unit and plum blossom type reinstallable irradiation test assembly

Abstract

The present invention relates to the field of research reactor irradiation technology, and provides a test piece clamping unit and a plum blossom-shaped reinstallable irradiation test assembly. The clamping unit includes a plurality of clamping members, each of which has a clamping portion at both ends, each of which has a clamping blind hole for clamping the test piece. The test piece is clamped between two adjacent clamping members, and the side walls of the clamping blind hole are provided with a first elastic member for providing a radial preload, and the bottom of the clamping blind hole is provided with a second elastic member for providing an axial preload; a plurality of pull rods, each of which has at least two pull rod holes passing through both ends, and the pull rods are inserted into the pull rod holes of adjacent clamping portions of two adjacent clamping members; and a plurality of fixing members arranged between the two clamping portions of the clamping member and connected to the ends of the pull rods. Compared with the prior art, the present invention not only can load test pieces in batches, but also ensures that each test piece has radial and axial preload.

Description

Technical Field

[0001] The present invention relates to the technical field of research reactor irradiation, and in particular to a test piece clamping unit and a plum blossom-type reinstallable irradiation test assembly. Background Art

[0002] Fuel elements are the smallest components of a fuel assembly. Prior to engineering applications, fuel assemblies must undergo in-pile irradiation testing and performance testing to comprehensively evaluate their radiation resistance, providing key experimental data and performance verification for design and development. Depending on the stage of fuel assembly development, varying degrees of in-pile irradiation testing are required. Generally, the final verification step is an assembly-level irradiation test to verify the fuel assembly's structural strength, thermal performance, hydraulic performance, compatibility, operability, radiation resistance, and corrosion resistance, among other properties. This provides reliable operational data for engineering applications.

[0003] The irradiation test assembly is generally a scaled-down fuel assembly. In a research reactor, the fuel element serves as a test piece and needs to be clamped and fixed by a clamping unit to ensure high temperature and high pressure, flow-induced vibration, flow velocity matching and other requirements during the test. For example, the patent document with publication number "CN110580961A" provides a clamping and fixing method for a rod-shaped test piece to meet the above requirements. However, this existing technology can only be applied to the clamping and fixing of a single test piece, and cannot be applied to batch loading of test pieces. Summary of the Invention

[0004] The object of the present invention is to provide a test piece clamping unit and a plum blossom-type reinstallable irradiation test assembly to solve the above-mentioned defects of the prior art.

[0005] The present invention is achieved through the following technical solutions:

[0006] A test piece clamping unit, comprising:

[0007] A plurality of clamping members, each having a clamping portion at both ends, each of which has a clamping blind hole for clamping a test piece, the test piece being clamped between two adjacent clamping members, a first elastic member for providing a radial preload force being provided on the sidewall of the clamping blind hole, and a second elastic member for providing an axial preload force being provided on the bottom of the clamping blind hole;

[0008] A plurality of pull rods, the clamping piece is provided with at least two pull rod holes passing through both ends, and the pull rods are passed through the pull rod holes of adjacent clamping parts of two adjacent clamping pieces;

[0009] A plurality of fixing members are arranged between the two clamping parts of the clamping member and connected to the end of the pull rod.

[0010] Optionally, the clamping blind holes of one or more of the clamping members located in the middle are replaced by clamping through holes, and the side walls of the clamping through holes are also provided with the first elastic member.

[0011] Optionally, the fixing member is a threaded cylinder, which is connected to the pull rod through threads.

[0012] Optionally, the first elastic member is a leaf spring, and the second elastic member is a disc spring.

[0013] Optionally, a gasket is provided on the end of the second elastic member that contacts the test piece.

[0014] The present invention also provides a plum blossom type reinstallable irradiation test assembly, comprising any one of the above-mentioned clamping units, and further comprising a center rod, a lower tube seat and a locking component, wherein the lower tube seat is fixedly connected to the lower end of the center rod;

[0015] Each clamping piece in the clamping unit is fan-shaped, and a wedge-shaped clamping block is provided on one side of the clamping piece, a wedge-shaped clamping groove is provided on the other side of the clamping piece, and a notch is provided on one side of the clamping blind hole that passes through both ends of the clamping piece to make the clamping piece elastic. Each clamping unit is assembled by the wedge-shaped clamping block and the wedge-shaped clamping groove to form a cylindrical clamping unit, and a mounting hole is formed in the center of the clamping unit. The clamping unit is sleeved on the center rod through the mounting hole and supported by the lower tube seat;

[0016] The locking component is arranged at the upper end of the center rod and is used to lock and clamp the whole.

[0017] Optionally, the cross section of the portion of the center rod on which the clamping unit is sleeved is perpendicular to the axis and has a polygonal structure, and the mounting hole can limit the rotation of the center rod and reserve a gap as a cooling channel.

[0018] Optionally, the locking component includes an upper tube seat, a lock core and a pressing seat; the portion of the center rod sleeved with the clamping unit is defined as a mounting section, a limiting boss is provided above the mounting section, and a cross-section of the limiting boss perpendicular to the axis is a polygonal structure, and the center rod is a polished rod section between the mounting section and the limiting boss;

[0019] The upper tube seat is sleeved on the mounting section and is provided with a support step for supporting the lock core. The distance between the limiting boss and the support step is equal to the length of the lock core. The lock core is provided with an inner hole that can cooperate with the limiting boss. After the lock core is inserted into the support step, it is rotated to a target angle so that the limiting boss limits the axial displacement of the lock core and the clamp as a whole.

[0020] The cross section of the lock core perpendicular to the axis is a polygonal structure, and a step anti-rotation hole is provided inside the pressing seat. The small diameter section of the step anti-rotation hole cooperates with the limiting boss, and the large diameter section of the step anti-rotation hole cooperates with the lock core.

[0021] The technical solution of the present invention has at least the following advantages and beneficial effects: In the present invention, a plurality of clamping members are provided, and adjacent clamping members are connected by a pull rod and a fixing member to form a clamping member. Each clamping unit can load multiple test pieces. Furthermore, the first elastic member provides radial preload force for the test piece to buffer radial vibration and impact loads, and the second elastic member provides axial preload force for the test piece to buffer axial vibration and impact loads. Thus, compared with the prior art, the present invention not only enables batch loading of test pieces, but also ensures that each test piece has both radial and axial preload force. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 A front view of a test piece clamping unit provided in Example 1;

[0024] Figure 2 for Figure 1 A magnified view of point A;

[0025] Figure 3 A schematic structural diagram of a test piece clamping unit provided in Example 1;

[0026] Figure 4 Schematic diagram of the structure of the clamping part

[0027] Figure 5 is a cross-sectional view of the clamping member;

[0028] Figure 6 is a top view of the clamping member (the first elastic member and the second elastic member are hidden);

[0029] Figure 7 A schematic structural diagram of a plum blossom-shaped reinstallable irradiation test assembly provided in Example 3;

[0030] Figure 8 A partial cross-sectional view of a plum blossom-shaped reinstallable irradiation test assembly provided in Example 3;

[0031] Figure 9 for Figure 8 Enlarged view of point B;

[0032] Figure 10 for Figure 9 CC cross-sectional view;

[0033] Figure 11is the main view of the center rod;

[0034] Figure 12 This is the main view of the upper tube seat;

[0035] Figure 13 for Figure 12 DD cross-sectional view;

[0036] Figure 14 This is the main view of the lock cylinder;

[0037] Figure 15 for Figure 14 EE cross-sectional view;

[0038] Figure 16 It is a structural diagram of the pressing seat;

[0039] Icon: 100-clamping unit, 101-clamping part, 1011-clamping blind hole, 1012-notch, 1013-wedge-shaped block, 1014-wedge-shaped slot, 102-pull rod, 103-fixing part, 104-first elastic part, 105-second elastic part, 106-cooling channel, 200-center rod, 201-installing section, 202-limiting boss, 300-lower tube seat, 400-locking part, 401-upper tube seat, 4011-support step, 402-lock core, 403-pressing seat, 4031-small diameter section, 4032-large diameter section, 500-test piece. DETAILED DESCRIPTION

[0040] Example 1

[0041] refer to Figure 1-Figure 5 A test piece 500 clamping unit 100 includes a plurality of clamping members 101 , a plurality of pull rods 102 and a plurality of fixing members 103 .

[0042] The clamping members 101 are provided with clamping portions at both ends, each of which is provided with blind clamping holes 1011 for clamping the test piece 500. The test piece 500 is clamped between two adjacent clamping members 101, i.e., the two ends of the test piece 500 are placed within the blind clamping holes 1011. The clamping members 101 are provided with at least two tie rod 102 holes extending through both ends, and the tie rods 102 are inserted into the tie rod 102 holes of the adjacent clamping portions of the two adjacent clamping members 101. It is easy to understand that the relative rotation between the two adjacent clamping members 101 can be restricted by at least two tie rods 102. As an option, the clamping members 101 of this embodiment are provided with only two tie rod 102 holes, i.e., two tie rods 102 are inserted into the two adjacent clamping members 101.

[0043] The fixing member 103 is arranged between the two clamping parts of the clamping member 101 and is connected to the end of the pull rod 102. As an option, the fixing member 103 of this embodiment is a threaded cylinder, and the end of the pull rod 102 is provided with a thread. The fixing member 103 and the pull rod 102 are connected by threads. It is easy to understand that in some embodiments, one fixing member 103 can be arranged between the two clamping parts of a clamping member 101, and the fixing member 103 is connected to two adjacent pull rods 102 at the same time; in other embodiments, of course, two fixing members 103 can also be arranged between the two clamping parts of a clamping member 101, that is, the adjacent ends of two adjacent pull rods 102 are each fixedly connected.

[0044] Each clamping unit 100 can be loaded with multiple test pieces 500. Optionally, nine clamping members 101 are provided in this embodiment, allowing for eight layers of test pieces 500 to be loaded, with one test piece 500 per layer, for a total of eight test pieces 500. Of course, in other embodiments, a clamping unit 100 can also have other numbers of clamping members 101 to load other numbers of test pieces 500.

[0045] A first elastic member 104 is provided on the sidewall of the blind hole. This member provides radial preload for the test piece 500, providing radial elastic support and positioning for the test piece 500. It also serves to buffer radial vibration and impact loads, dampening the flow-induced vibrations of the test piece 500 generated by the hydraulic scouring of the circuit. Optionally, a leaf spring is used as first elastic member 104 in this embodiment. Leaf springs can be categorized as straight or curved based on their shape. This embodiment utilizes a curved leaf spring, which can be secured via resistance welding or laser welding.

[0046] A second elastic member 105 is installed at the bottom of the blind clamping hole 1011. This member provides axial preload for the test piece 500, buffering axial vibration and impact loads, and dampening flow-induced vibrations generated by the hydraulic scouring of the circuit. Alternatively, a disc spring is used for the second elastic member 105 in this embodiment. Furthermore, due to the high stiffness of disc springs, a gasket is installed on the end of the second elastic member 105 that contacts the test piece 500 to prevent damage to the end of the test piece 500 caused by local point contact.

[0047] Example 2

[0048] The difference between this embodiment and embodiment 1 is that the clamping blind holes 1011 of one or more clamping members 101 in the middle of this embodiment are replaced with clamping through holes. This arrangement enables the clamping unit 100 to clamp test pieces 500 of different lengths.

[0049] For ease of understanding, the clamping member 101 provided with the clamping through-hole is defined as an intermediate clamping member. If the test piece 500 loaded in Example 1 is defined as a short test piece 500, this embodiment can load not only short test pieces 500 but also long test pieces 500 that are longer than the short test piece 500. In practical applications, for example, if the clamping blind holes 1011 in the second to fourth clamping members 101 from top to bottom in Example 1 are replaced with intermediate clamping members, the long test piece 500 of this embodiment will be clamped between the first and fifth clamping members 101. In other words, the clamping unit 100 provided in this embodiment can handle one long test piece 500 and four short test pieces 500. The sidewalls of the clamping through-holes of the intermediate clamping members are also provided with first elastic members 104, meaning that the intermediate clamping members provide only radial support and do not apply axial preload.

[0050] Example 3

[0051] refer to Figure 7 and Figure 8 This embodiment provides a plum blossom-shaped reinstallable irradiation test assembly, comprising a plurality of clamping units 100. Optionally, this embodiment includes five clamping units 100 of Example 1, which can hold a total of four short test pieces 500. It will be readily understood that in other embodiments, the test assembly can also be comprised of the clamping units 100 of Example 2, and the number of clamping units 100 can also be other.

[0052] On the basis of the above, the test assembly further includes a center rod 200 , a lower tube seat 300 and a locking component 400 .

[0053] Each clamping member 101 in the clamping unit 100 is fan-shaped. Figure 10 and Figure 12 A wedge-shaped block 1013 is provided on one side of the clamping member 101, and a wedge-shaped slot 1014 is provided on the other side of the clamping member 101. The five clamping units 100 are assembled by means of the wedge-shaped block 1013 and the wedge-shaped slot 1014, forming a cylindrical clamping unit. The cross-section of the clamping unit perpendicular to the axis is shaped like a plum blossom. A notch 1012 is provided on one side of the clamping blind hole 1011, extending through both ends of the clamping member 101. This provides the clamping member 101 with elasticity. When the clamping member 101 is squeezed, the size of the notch 1012 can be reduced, ensuring that the five clamping units 100 can be assembled smoothly.

[0054] The lower tube seat 300 is fixedly connected to the lower end of the center rod 200; when the five clamping units 100 are combined to form a clamping whole, a mounting hole is formed at the center of the clamping whole. The clamping whole is sleeved on the center rod 200 through the mounting hole and supported by the lower tube seat 300; further, the part of the center rod 200 on which the clamping whole is sleeved is defined as a mounting section 201. The cross-section of the mounting section 201 perpendicular to the axis is a polygonal structure. The mounting hole can limit the rotation of the center rod 200 and a gap is reserved as a cooling channel 106. Figure 10 On this basis, each clamping member 101 of this embodiment is arc-shaped near the center of the clamping body, that is, the mounting hole is composed of five arc segments, each arc segment is tangent to the corresponding side of the mounting segment 2012, so that the rotation of the center rod 200 is restricted and there is a gap to serve as a cooling channel 106.

[0055] The locking member 400 is provided at the upper end of the center rod 200 and is used to lock and clamp the entire structure. Figure 9 、 Figures 11-16 In this embodiment, the locking component 400 includes an upper tube seat 401, a lock core 402 and a pressing seat 403. A limiting boss 202 is provided above the mounting section 201 of the center rod 200. The center rod 200 is a bare rod section between the mounting section 201 and the limiting boss 202.

[0056] The upper tube seat 401 is sleeved on the mounting section 201, that is, the upper tube seat 401 is provided with a hole that cooperates with the mounting section 201, and the interior of the upper tube seat 401 is provided with a support step 4011 for supporting the lock core 402, and the distance between the limiting boss 202 and the support step 4011 is equal to the length of the lock core 402, and the cross-section of the limiting boss 202 perpendicular to the axis is a polygonal structure (as an option, this embodiment is a regular pentagonal structure), and the interior of the lock core 402 is provided with an inner hole that can cooperate with the limiting boss 202. After the lock core 402 is inserted into the support step 4011, it is just aligned with the light rod section, and then rotated to the target angle. Under the action of the limiting boss 202, the axial displacement of the lock core 402 and the clamping unit 100 is limited.

[0057] The cross section of the lock core 402 perpendicular to the axis is also polygonal (as an option, this embodiment also has a regular pentagonal structure). The interior of the compression seat 403 is provided with a stepped anti-rotation hole. The small diameter section 4031 of the stepped anti-rotation hole cooperates with the limiting boss 202, and the large diameter section 4032 of the stepped anti-rotation hole cooperates with the lock core 402. In this way, the compression seat 403 cannot rotate relative to the center rod 200, and the lock core 402 cannot rotate relative to the compression seat 403, thereby achieving a locking function. Furthermore, in actual application, a locking nut (not shown) can also be provided on the compression seat 403, and the locking nut is threadedly connected to the center rod 200 to limit the axial position of the compression seat 403.

[0058] In addition, it should be understood that the upper tube seat 401 , the pressing seat 403 and the lower tube seat 300 should all be provided with corresponding holes as coolant circulation channels to facilitate the coolant to enter the above-mentioned cooling channel 106 .

[0059] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A plum blossom type reinstallable irradiation test assembly, comprising a plurality of test piece clamping units, the test piece clamping units comprising a plurality of clamping members, a plurality of pull rods and a plurality of fixing members, a clamping portion is provided at both ends of the clamping member, the clamping portion is provided with a clamping blind hole for clamping the test piece, the test piece is clamped between two adjacent clamping members, the side wall of the clamping blind hole is provided with a first elastic member for providing a radial preload, the bottom of the clamping blind hole is provided with a second elastic member for providing an axial preload; the clamping member is provided with at least two pull rod holes passing through both ends, the pull rod is passed through the pull rod holes of adjacent clamping members of two adjacent clamping members; the fixing member is arranged between the two clamping members and connected to the end of the pull rod; it is characterized in that, The test assembly also includes a center rod, a lower tube seat and a locking component, wherein the lower tube seat is fixedly connected to the lower end of the center rod; Each clamping piece in the clamping unit is fan-shaped, and a wedge-shaped clamping block is provided on one side of the clamping piece, a wedge-shaped clamping groove is provided on the other side of the clamping piece, and a notch is provided on one side of the clamping blind hole that passes through both ends of the clamping piece to make the clamping piece elastic. Each clamping unit is assembled by the wedge-shaped clamping block and the wedge-shaped clamping groove to form a cylindrical clamping unit, and a mounting hole is formed in the center of the clamping unit. The clamping unit is sleeved on the center rod through the mounting hole and supported by the lower tube seat; The locking component is arranged at the upper end of the center rod and is used to lock and clamp the whole.

2. The plum blossom type reinstallable irradiation test assembly according to claim 1, characterized in that: The clamping blind holes of one or more clamping members located in the middle are replaced by clamping through holes, and the side walls of the clamping through holes are also provided with the first elastic member.

3. The plum blossom type reinstallable irradiation test assembly according to claim 1, characterized in that: The fixing piece is a threaded cylinder, which is connected to the pull rod through threads.

4. The plum blossom type reinstallable irradiation test assembly according to claim 1, characterized in that: The first elastic member is a leaf spring, and the second elastic member is a disc spring.

5. The plum blossom type reinstallable irradiation test assembly according to claim 1, characterized in that: A gasket is provided at one end of the second elastic member that contacts the test member.

6. The plum blossom type reinstallable irradiation test assembly according to claim 1, characterized in that: The cross section of the portion of the central rod sleeved with the clamping unit is perpendicular to the axis and has a polygonal structure. The mounting hole can limit the rotation of the central rod and a gap is reserved as a cooling channel.

7. The plum blossom type reinstallable irradiation test assembly according to claim 1, characterized in that: The locking component includes an upper tube seat, a lock core and a pressing seat; the portion of the center rod that sleeves the clamping unit is defined as a mounting section, a limiting boss is provided above the mounting section, and the cross-section of the limiting boss perpendicular to the axis is a polygonal structure, and the center rod is a polished rod section between the mounting section and the limiting boss; The upper tube seat is sleeved on the mounting section and is provided with a support step for supporting the lock core. The distance between the limiting boss and the support step is equal to the length of the lock core. The lock core is provided with an inner hole that can cooperate with the limiting boss. After the lock core is inserted into the support step, it is rotated to a target angle so that the limiting boss limits the axial displacement of the lock core and the clamp as a whole. The cross section of the lock core perpendicular to the axis is a polygonal structure, and a step anti-rotation hole is provided inside the pressing seat. The small diameter section of the step anti-rotation hole cooperates with the limiting boss, and the large diameter section of the step anti-rotation hole cooperates with the lock core.

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