Nuclear fuel cladding tube spiral rib rolling apparatus
By using a nuclear fuel cladding tube spiral rib rolling equipment, which utilizes a drive sleeve and planetary roll assembly to roll the spiral ribs, the problems of easy detachment of the outer wall winding wire and low precision are solved, thus improving the reliability and yield of the cladding tube.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA NUCLEAR POWER TECH RES INST CO LTD
- Filing Date
- 2022-11-03
- Publication Date
- 2026-06-05
AI Technical Summary
In the existing technology, the spiral winding wire on the outer wall of the nuclear fuel cladding tube is prone to falling off due to weld point failure, resulting in poor reliability. In addition, the spiral rib thin-walled cladding tube produced by the torsion method has low precision, low yield, and is prone to fatigue failure.
The spiral rib rolling equipment for nuclear fuel cladding tubes, including a drive sleeve and a planetary roll assembly, is used to form spiral ribs through rolling, avoiding fatigue failure caused by torsion and ensuring the accuracy and yield of the spiral ribs.
It improves the service life of nuclear fuel cladding tubes and the precision of helical ribs, increases the yield rate, and avoids deformation and precision loss caused by torsion.
Smart Images
Figure CN115722615B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of nuclear fuel equipment manufacturing processes, and more specifically, to a nuclear fuel cladding tube spiral rib rolling equipment. Background Technology
[0002] In liquid metal-cooled fast reactor fuel assemblies, fuel cladding tubes are typically positioned by spirally winding wire around the outer wall, with the wire secured by spot welding at both ends. However, this type of cladding tube, where the wire is wound, is susceptible to detachment due to damage to the welds when subjected to high-temperature, high-pressure coolant corrosion and erosion. Therefore, it is necessary to integrally mold the wire structure with the cladding tube to ensure its high reliability.
[0003] The integral molding method for thin-walled clad tubes with helical ribs in related technologies involves installing straight ribs onto the tube and then twisting it to obtain the helical ribbed thin-walled clad tube. This process is complex and leads to low efficiency. Furthermore, the twisting method for obtaining the helical ribs cannot guarantee that the rotation angle is the same at every point in the thin-walled clad tube with helical ribs; and the tube's inner roundness, cross-sectional dimensional accuracy, and straightness will all suffer varying degrees of loss and reduction. This results in low precision and a low yield rate for the finished thin-walled clad tube with helical ribs. During the rotation process, the thin-walled clad tube is prone to fatigue failure, reducing its service life. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide an improved rolling equipment for spiral ribs of nuclear fuel cladding tubes.
[0005] The technical solution adopted by this invention to solve its technical problem is: constructing a nuclear fuel cladding tube spiral rib rolling device, comprising:
[0006] Drive sleeve, rotatably set; and
[0007] At least two rolls are provided for rolling thin-walled cladding tubes with helical ribs. The at least two rolls are disposed in the drive sleeve and arranged in a planetary roller configuration relative to the drive sleeve. Each roll includes a drive section that cooperates with the drive sleeve and a rolling section that is connected to the drive section.
[0008] In some embodiments, the drive sleeve includes internal teeth that mesh with the transmission section.
[0009] In some embodiments, the nuclear fuel cladding tube spiral rib rolling apparatus includes a roll assembly comprising a limiting device and at least two rolls rotatably mounted on the limiting device about their own axis and arranged in a circular array relative to the axis of the drive sleeve.
[0010] In some embodiments, the at least two rolls comprise a plurality of rolls, the number of which is the same as or half the number of helical ribs in the thin-walled tube with helical ribs.
[0011] In some embodiments, each roll includes at least two grooves arranged in parallel and evenly distributed at a certain angle on the surface of the roll, and the distance between adjacent grooves on the surface of the roll is equivalent to the distance between adjacent ribs on the tube surface of the thin-walled cladding tube with helical ribs.
[0012] In some embodiments, the shape of the transverse cross section of the groove is the same as the shape of the transverse cross section of the helical rib of the thin-walled cladding tube with helical ribs.
[0013] In some embodiments, the groove is set at the same angle as the spiral rib of the thin-walled cladding tube with spiral ribs, and the direction of deflection relative to the axis is opposite.
[0014] In some embodiments, the cross-section of the groove varies uniformly from small to large, and the maximum cross-section is the same size as the transverse cross-section of the spiral rib of the thin-walled cladding tube with spiral ribs.
[0015] In some embodiments, the rolling section includes a bite rolling section and a sizing and finishing section, wherein the sizing and finishing section is integrally formed with the bite rolling section.
[0016] In some embodiments, the axes of the bite-in rolling section and the sizing and finishing section coincide, the bite-in rolling section is frustum-shaped, the sizing and finishing section is cylindrical, and the sizing and finishing section is connected to the bottom surface of the bite-in rolling section.
[0017] In some embodiments, the angle between the generatrix of the frustum of the biting rolling section and the axis is 2.5°-10°.
[0018] In some embodiments, the roll further includes two cylindrical connecting columns, which are respectively disposed at both axial ends of the roll, and the roll is rotatably connected to the limiting device through the connecting columns.
[0019] In some embodiments, the axis of the connecting column coincides with the axis of the rolling section and the transmission section.
[0020] In some embodiments, the limiting device includes a limiting plate and a connecting hole disposed on the limiting plate, wherein the connecting post is rotatably installed in the connecting hole.
[0021] In some embodiments, the connecting holes include a plurality of connecting holes arranged in a planetary pattern, with equal distances between adjacent connecting holes.
[0022] Implementing this invention has at least the following beneficial effects: Since the nuclear fuel cladding tube spiral rib rolling equipment of this invention includes a drive sleeve and a roll assembly, the drive sleeve can drive the roll assembly to rotate planetarily. The thin-walled cladding tube with spiral ribs can be formed by rolling the roll assembly without twisting, thus avoiding fatigue damage caused by twisting and increasing service life. Simultaneously, because the limiting device in the roll assembly can restrict the position of the rolls, the spiral ribs obtained using this nuclear fuel cladding tube spiral rib rolling equipment have high precision and a high yield rate. Attached Figure Description
[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:
[0024] Figure 1 This is a three-dimensional structural schematic diagram of the nuclear fuel cladding tube spiral rib rolling equipment in some embodiments of the present invention;
[0025] Figure 2 yes Figure 1 A three-dimensional structural diagram of the nuclear fuel cladding tube spiral rib rolling equipment in its disassembled state.
[0026] Figure 3 yes Figure 1 A three-dimensional structural diagram of another disassembled state of the nuclear fuel cladding tube spiral rib rolling equipment shown.
[0027] Figure 4 yes Figure 1 A schematic diagram of the fit between the rolls and the sleeve in the spiral rib rolling mill for nuclear fuel cladding tubes;
[0028] Figure 5 yes Figure 1 The diagram shows a three-dimensional structure of the nuclear fuel cladding tube spiral rib rolling equipment during the rolling operation.
[0029] Figure 6 yes Figure 1 The diagram shows the principle of the nuclear fuel cladding tube spiral rib rolling equipment during the rolling operation. Detailed Implementation
[0030] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[0031] Figure 5The illustration shows a thin-walled cladding tube 100 with helical ribs according to some embodiments of the present invention. In some embodiments, the thin-walled cladding tube 100 with helical ribs may be rolled from a tube blank 200, and may include a tube body 101 and a plurality of helical ribs 102. The plurality of helical ribs 102 are wound at equal intervals around the tube body 101 and integrally formed with the tube body 101. The transverse cross-section of each of the plurality of helical ribs 102 is semi-circular; it is understood that, in addition to a semi-circular transverse cross-section, the transverse cross-section of the helical rib 102 may also be trapezoidal, square, or rectangular.
[0032] Figures 1 to 4 A nuclear fuel cladding tube helical rib rolling apparatus 1 is shown, which can be used to roll a thin-walled cladding tube 100 with helical ribs. The thin-walled cladding tube 100 with helical ribs may include a rotatable drive sleeve 10 and a roll assembly 20. In some embodiments, the drive sleeve 10 is cylindrical and rotatably arranged along its axis; the roll assembly 20 is mounted inside the drive sleeve 10 and has a rotation axis that coincides with the axis of the drive sleeve 10. The roll assembly 20 can rotate under the rotational drive of the drive sleeve 10 to roll the thin-walled cladding tube 100 with helical ribs.
[0033] In some embodiments, the drive sleeve 10 may include a sleeve body 11 and an internal toothed portion 12 disposed within the sleeve body 11. The sleeve body 11 is fitted over the roll assembly 20 to define the position of the roll assembly 20. The internal toothed portion 12 can engage with the roll assembly 20 to provide radial support to the roll assembly 20, enabling the roll assembly 20 to roll helical ribs 102 onto the tube blank 200.
[0034] In some embodiments, the roll assembly 20 may include a limiting device 21 and a plurality of rolls 22. In some embodiments, there are two limiting devices 21, each installed at one end of a roll 22, which can be used to limit the position between the plurality of rolls 22 to ensure a reasonable distribution of the spiral ribs 102 in the thin-walled cladding tube 100 rolled by the rolls 22. Because the position of the rolls 22 is limited by the limiting device 21, the distribution of the spiral ribs 102 processed on the tube blank 200 is defined, further resulting in the thin-walled cladding tube 100 with spiral ribs rolled using this nuclear fuel cladding tube spiral rib rolling equipment 1 having good precision.
[0035] In some embodiments, the plurality of rolls 22 are arranged in a planetary configuration, with each roll 22 arranged in a circular array relative to the axis of the drive sleeve 10. The number of rolls 22 corresponds roughly to the number of helical ribs 102 on the cladding tube. Specifically, the number of rolls 22 may be equal to or half the number of helical ribs 102. In some embodiments, the number of rolls 22 is typically set to an even number. In this case, the rolling ribs are always positioned relative to each other, so that the ribs in the plurality of rolls 22 can be rolled in pairs. This prevents the billet 200 from deforming due to unilateral rolling, thus avoiding low rolling quality and uneven rolling ribs. A plurality of rolls 22 are mounted axially inside a drive sleeve 10, and the radial support of the plurality of rolls 22 is provided by the drive sleeve 10. This radial support enables the plurality of rolls 22 to radially compress the tube blank 200, causing deformation of the tube blank 200, thereby enabling the nuclear fuel cladding tube helical rib rolling apparatus 1 to process helical ribs 102 on the thin-walled cladding tube 100 with helical ribs. Understandably, in some embodiments, the plurality of rolls 22 are arranged in a planetary roller configuration relative to the drive sleeve 10.
[0036] Since the radial position of the roll 22 is restricted by the drive sleeve 10, the roll 22 can produce rolling marks during the relative extrusion process with the tube blank 200 to be processed. In addition to driving the roll 22 to rotate, the drive sleeve 10 can also ensure that the roll 22 can generate sufficient radial pressure to deform the tube blank 200 under pressure.
[0037] In some embodiments, the limiting device 21 may include a limiting disk 211, connecting holes 212, and through holes 213. In some embodiments, the limiting disk 211 is disc-shaped, its size sufficient to cover a plurality of rolls 22, thereby fixing the plurality of rolls 22. The plane of the limiting disk 211 is perpendicular to the axis of the plurality of rolls 22, allowing the limiting disk 211 to simultaneously fix the plurality of rolls 22 at their ends. The center of the limiting disk 211 is collinear with the rotation axis of the plurality of rolls 22 to facilitate rotation of the limiting disk 211. In some embodiments, the connecting holes 212 may include multiple connecting holes 212, which may be located on the limiting disk 211 and are centrally symmetrically arranged with respect to the center of the limiting disk 211. The distance between two adjacent connecting holes 212 is approximately equal, thereby ensuring that the plurality of rolls 22 are evenly distributed according to the positions of the connecting holes 212. Specifically, the number of connecting holes 212 is consistent with the number of rolls 22. In some embodiments, the line connecting the connecting holes 212 corresponding to the two limiting devices 21 is parallel to the axis of the tube blank 200 to be rolled, so as to ensure that the roll 22 is subjected to uniform force during rolling. The through hole 213 is provided at the center of the limiting plate 211, and the tube blank 200 can pass through the through hole 213, the diameter of which is larger than the cross-sectional size of the tube blank 200 to be rolled.
[0038] Each roll 22 may include a rolling section 221, a drive section 222, and a connecting column 223 in some embodiments. The rolling section 221 and the drive section 222 may be generally cylindrical, coaxial with each other. The connecting column 223 is a smaller cylinder, with its axis collinear with the axes of the rolling section 221 and the drive section 222. In some embodiments, the rolling section 221 and the drive section 222 are integrally formed. The rolling section 221 is used to roll helical ribs 102 onto the tube blank 200. The drive section 222 cooperates with the drive sleeve 10 and can rotate under the drive of the drive sleeve 10. In some embodiments, the rotation of the drive section 222 may include rotation and revolution about the axis of the tube blank 200 placed in the nuclear fuel cladding tube helical rib rolling mill 1. In some embodiments, the connecting post 223 may include two connecting posts 223, which are located at both ends of the roll 22. Specifically, the two connecting posts 223 are respectively installed on the outer side of the transmission section 222 and the rolling section 221, and are integrally formed with the transmission section 222 and the rolling section 221.
[0039] In some embodiments, the rolling section 221 may include a bite-in rolling section 2211 and a sizing and finishing section 2212. In some embodiments, the bite-in rolling section 2211 may be frustum-shaped, with the generatrix of the frustum forming an angle of 2.5°-10° with the axis. The bottom surface of the frustum-shaped bite-in rolling section 2211 is connected to the sizing and finishing section 2212, with the bottom surface at the end with the larger diameter of the frustum. The sizing and finishing section 2212 is cylindrical, with a diameter approximately equal to the maximum diameter of the frustum-shaped bite-in rolling section 2211; its axis coincides with the axis of the bite-in rolling section 2211. In some embodiments, the sizing and finishing section 2212 and the bite-in rolling section 2211 are integrally formed, constituting the main structure of the roll 22.
[0040] A plurality of grooves 2213 are evenly and parallelly distributed at a certain angle on the surface of the roll 22, and the shape of the transverse cross-section of the grooves 2213 corresponds to the transverse cross-section of the spiral rib 102 to be processed. Specifically, the angle of the grooves 2213 distributed on the roll 22 causes the grooves 2213 to be spirally arranged on the roll 22, and the direction of the spiral is opposite to the rotation direction of the spiral rib 102 on the cladding tube to be processed. In some embodiments, the shape of the transverse cross-section of the groove 2213 can be semi-circular; it can be understood that when the transverse cross-section of the spiral rib 102 is trapezoidal, square or rectangular, the transverse cross-section of the groove 2213 is correspondingly set as trapezoidal, square or rectangular. In some embodiments, a plurality of grooves 2213 are inclined, so that the ribs obtained during the rolling process are spiral; the distance between two adjacent grooves 2213 is equal, so that the spiral ribs 102 with equal spacing can be obtained during the rolling process.
[0041] In some embodiments, the grooves 2213 have the same cross-section perpendicular to the groove distribution direction to obtain helical ribs 102 with uniform width during rolling. Understandably, in some embodiments, the grooves 2213 may also be configured such that the cross-section perpendicular to the groove direction can uniformly vary from small to large, and the maximum cross-section is the same size as the transverse cross-section of the helical rib of the thin-walled cladding tube with helical ribs; thereby making it easier to roll out the ribs. The distance between two adjacent grooves 2213 is set such that their distance on the surface of the roll 22 is equivalent to the distance between adjacent helical ribs 102 on the tube surface of the thin-walled cladding tube 100 with helical ribs. Understandably, different thin-walled cladding tubes 100 with helical ribs require different rolls 22 for rolling, and the difference between the different rolls 22 lies in the different distances between two adjacent grooves 2213 on the roll 22.
[0042] The drive section 222 is cylindrical and can be connected to one end of the sizing and finishing section 2212 relative to the biting rolling section 2211. Specifically, the drive section 222 and the sizing and finishing section 2212 are integrally formed. The drive section 222 can cooperate with the drive sleeve 10 to realize the rotation of a plurality of rolls 22, thereby enabling the rolls 22 to roll the billet 200, causing it to deform to obtain the desired structure. Specifically, in some embodiments, the rotating section 14 may include an external toothed portion 2221, which can cooperate with the drive sleeve 10 to drive the rolls to rotate.
[0043] In some embodiments, the transmission section 222 may include an external toothed portion 2221 that can engage with the internal toothed portion 12 of the drive sleeve 10 to achieve rotation of the roll 22. Specifically, the internal toothed portion 12 of the drive sleeve 10 can mesh with the external toothed portion 2221 on the transmission section 222. The meshing point can restrict the direction of the roll 22, so that the axis of the roll 22 is always parallel to the axis of the tube blank 200, preventing angular torsion and thus affecting the normal processing of the thin-walled cladding tube 100 with helical ribs. In some embodiments, the length of the internal toothed portion 12 is equivalent to the thickness of the external toothed portion 2221 to maximize the meshing of the drive sleeve 10 and the roll 22, thereby ensuring the support strength of the drive sleeve 10 for the roll 22.
[0044] In some embodiments, the connecting post 223 is cylindrical and may include two sections. The two sections are located at opposite ends of the plurality of rolls 22. Specifically, the two connecting posts 223 are located at one end of the bite-in rolling section 2211 and one end of the drive section, respectively, and are positioned at their centers. In some embodiments, the axes of the bite-in rolling section 2211, the sizing and finishing section 2212, the drive section 222, and the connecting post 223 are collinear, thereby ensuring uniform pressure applied to the billet 200 by the rolls during rolling, thus guaranteeing the quality of the processed spiral ribs 102.
[0045] See also Figure 5 and Figure 6 In some embodiments, the tube blank 200 is a hollow cylindrical structure. The tube blank 200 can be made of materials such as stainless steel, zirconium and zirconium alloys, ferritic martensitic alloy steel, or oxide dispersion reinforced alloy steel. During rolling, a hard mandrel can be provided inside the tube blank 200 to radially press against the tube blank 200 from the inside out, facilitating rolling and forming. It is understood that, in addition to the aforementioned tube blank 200 materials, other materials that meet processing and usage standards can also be used.
[0046] Because different materials are used for the tube blank 200, different methods can be used to complete the rolling process when rolling the tube blank 200. Understandably, the rolling deformation method can be single-pass rolling deformation, multiple-pass rolling deformation, or heating the tube blank 200 before rolling. Specifically, for materials with high plasticity, multiple-pass rolling deformation can be used. For materials whose plasticity is greatly affected by temperature, the tube blank 200 can be heated until its temperature rises to a suitable processing state for easy deformation before processing. Different rolling processes can directly produce a thin-walled clad tube 100 with spiral ribs, and the tube body 101 of the thin-walled clad tube 100 with spiral ribs is integrally formed with the plurality of spiral ribs 102.
[0047] The outer diameter of the tube blank 200 should be slightly larger than that of the cladding tube to be rolled. In some embodiments, the outer diameter of the tube blank 200 should be 1-2 mm larger than the outer diameter of the finished thin-walled cladding tube 100 with spiral ribs, and its wall thickness should be 0.5 mm greater than the sum of the wall thickness of the finished thin-walled cladding tube 100 with spiral ribs and the height of the spiral ribs 102. Since the wall thickness of the tube blank 200 will become thinner and the outer diameter of the tube blank 200 will become smaller when the tube blank 200 is rolled into the thin-walled cladding tube 100 with spiral ribs, while ensuring the fullness of the ribs, the tube blank 200 should also be configured such that, after rolling, the reduction in the outer diameter of the tube blank 200 is greater than 20%, and the reduction in wall thickness is greater than 20%. In some embodiments, the wall thickness of the finished thin-walled cladding tube 100 with spiral ribs is 0.30-0.60 mm at non-rib positions, and the thickness including the ribs at the rib positions is 1-2 mm.
[0048] Understandably, the above-mentioned technical features can be used in any combination without restriction.
[0049] The above embodiments merely illustrate specific implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can freely combine the above technical features without departing from the concept of the present invention, and can also make several modifications and improvements, all of which fall within the protection scope of the present invention. Therefore, all equivalent transformations and modifications made with respect to the scope of the claims of the present invention should fall within the scope of the claims of the present invention.
Claims
1. A spiral rib rolling mill for nuclear fuel cladding tubes, characterized in that, include: The drive sleeve (10) is rotatably set; as well as At least two rolls (22) are used for rolling thin-walled cladding tubes (100) with helical ribs. The at least two rolls (22) are disposed in the drive sleeve and arranged in a planetary roller configuration relative to the drive sleeve. Each roll (22) includes a drive section (222) that cooperates with the drive sleeve and a rolling section (221) that is connected to the drive section (222). The drive sleeve (10) includes an internal toothed portion (12), which meshes with the transmission section (222); The nuclear fuel cladding tube spiral rib rolling equipment (1) also includes a limiting device (21). Each roll (22) includes at least two grooves (2213), which are arranged in parallel and evenly distributed at a certain angle on the surface of the roll (22). The distance between adjacent grooves (2213) on the surface of the roll (22) is equivalent to the distance between adjacent spiral ribs (102) on the surface of the thin-walled sheathed tube (100) with spiral ribs. The roll (22) also includes two cylindrical connecting columns (223). The connecting columns (223) are respectively disposed at both ends of the axial direction of the roll (22). The roll (22) is rotatably connected to the limiting device (21) through the connecting columns (223). The axis of the connecting column (223) coincides with the axis of the rolling section (221) and the transmission section (222); The limiting device (21) includes a limiting plate (211) and a connecting hole (212) disposed on the limiting plate (211), and the connecting post (223) is rotatably installed in the connecting hole (212).
2. The nuclear fuel cladding tube spiral rib rolling equipment according to claim 1, characterized in that, The at least two rolls (22) are rotatably mounted on the limiting device (21) about their own axis and are arranged in a circular array relative to the axis of the drive sleeve (10).
3. The nuclear fuel cladding tube spiral rib rolling equipment according to claim 1, characterized in that, The number of the at least two rolls (22) is the same as or half the number of the spiral ribs (102) of the thin-walled sheath tube (100) with spiral ribs.
4. The nuclear fuel cladding tube spiral rib rolling equipment according to claim 1, characterized in that, The shape of the transverse cross section of the groove (2213) is the same as the shape of the transverse cross section of the spiral rib (102) of the thin-walled cladding tube (100) with spiral ribs.
5. The nuclear fuel cladding tube spiral rib rolling equipment according to claim 4, characterized in that, The angle of the groove (2213) is consistent with the angle of the spiral rib (102) of the thin-walled cladding tube (100) with spiral ribs, and the direction of deflection relative to the axis is opposite.
6. The nuclear fuel cladding tube spiral rib rolling equipment according to claim 1, characterized in that, The cross-section of the groove (2213) changes uniformly from small to large, and the maximum cross-section is the same as the transverse cross-section of the spiral rib (102) of the thin-walled shell tube (100) with spiral ribs.
7. The nuclear fuel cladding tube spiral rib rolling equipment according to claim 1, characterized in that, The rolling section (221) includes a bite rolling section (2211) and a sizing and finishing section (2212), wherein the sizing and finishing section (2212) and the bite rolling section (2211) are integrally formed.
8. The nuclear fuel cladding tube spiral rib rolling equipment according to claim 7, characterized in that, The axes of the bite-in rolling section (2211) and the sizing and finishing section (2212) coincide. The bite-in rolling section (2211) is frustum-shaped, and the sizing and finishing section (2212) is cylindrical. The sizing and finishing section (2212) is connected to the bottom surface of the bite-in rolling section (2211).
9. The nuclear fuel cladding tube spiral rib rolling equipment according to claim 8, characterized in that, The angle between the generatrix of the frustum of the biting rolling section (2211) and the axis is 2.5°-10°.
10. The nuclear fuel cladding tube spiral rib rolling equipment according to claim 1, characterized in that, The connecting hole (212) includes a plurality of connecting holes (212), which are distributed in a planetary pattern, and the distance between two adjacent connecting holes (212) is equal.