A kind of anti-wrinkle precision pipe bending device for thin-walled niobium-zirconium tube

Abstract

The utility model discloses a kind of anti-wrinkling precision pipe bending device for thin-wall niobium-zirconium tube, including workbench, the clamping mechanism for clamping in the end of thin-wall pipe material being set on workbench, and the fixing mechanism and rotating mechanism for the anti-wrinkling precision pipe bending of thin-wall pipe material are set on workbench;Rotating mechanism includes servo motor and rotating core, the bottom end of rotating core is fixedly installed with the rotating gear engaged with fixed gear, rotating forming wheel is detachably set on rotating core by coupling structure, the cavity of thin-wall pipe material is filled with support, and the two ends of thin-wall pipe material are provided with plug.The utility model ensures the bending radius accurate by gear fixed ratio transmission;Realize the quick die change of multiple radius, multiple section pipe material by modular wheel group;Combining with diamond filling support in pipe and lubricating layer protection outside pipe, constitute a collaborative system, fundamentally solve the wrinkling, flattening, rebound and surface scratch problem when thin-wall niobium-zirconium tube small radius bending.

Description

Technical Field

[0001] This utility model belongs to the field of metal pipe processing technology, specifically relating to an anti-wrinkle precision pipe bending device for thin-walled niobium-zirconium pipes. Background Technology

[0002] Niobium-zirconium tubes play a crucial role in high-end technology fields such as aerospace, superconducting magnets, and the nuclear industry due to their excellent high-temperature resistance, corrosion resistance, and good mechanical properties. In practical applications, they often need to be bent into specific shapes, such as 180° U-shaped bends. However, due to the high deformation resistance of niobium-zirconium tubes, and especially when they are thin-walled (e.g., 32mm in diameter with a wall thickness of only 1.2mm), they face three problems during cold bending: first, the inner wall is prone to instability and wrinkling under compressive stress; second, the entire cross-section is prone to elliptic distortion (i.e., flattening) under bending moment; and third, the inherent elasticity of the material causes significant springback after bending, making it difficult to precisely control the forming angle and radius. Furthermore, friction between the outer wall of the tube and the mold during bending can easily cause surface scratches, affecting the product's appearance and performance.

[0003] Currently, there are some tooling solutions for bending thin-walled tubes, but the bending process relies on manual labor, resulting in poor precision and consistency, and it cannot achieve rapid switching between different radii and tube shapes. The tube cavity is filled with low-melting-point alloys or paraffin wax for internal support, but low-melting-point alloys are expensive and easily contaminate the tube, while paraffin wax has limited support rigidity and is insufficient for supporting high-strength niobium-zirconium tubes. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide an anti-wrinkle precision bending device for thin-walled niobium-zirconium tubes, addressing the shortcomings of the prior art.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a precision bending device for anti-wrinkle of thin-walled niobium-zirconium tubes, characterized in that: it includes a worktable, a clamping mechanism set on the worktable for clamping the end of the thin-walled tube, and a fixing mechanism and a rotating mechanism set on the worktable for anti-wrinkle precision bending of the thin-walled tube. The fixing mechanism includes a fixing core fixed on the workbench and a fixing gear fixedly installed at the bottom of the fixing core. The fixing forming wheel is detachably sleeved on the fixing core through a connecting structure. The rotating mechanism includes a servo motor, the output shaft of which passes through the rotating core and is fixedly connected to the rotating core. A rotating gear that meshes with a fixed gear is fixedly installed at the bottom end of the rotating core. The rotating forming wheel is detachably sleeved on the rotating core through a connecting structure. The thin-walled pipe has a support body inside its cavity, and the two ends of the thin-walled pipe are provided with plugs for sealing and securing the support body.

[0006] The aforementioned anti-wrinkle precision bending device for thin-walled niobium-zirconium tubes is characterized in that: the support body is a diamond abrasive support body.

[0007] The aforementioned anti-wrinkle precision bending device for thin-walled niobium-zirconium tubes is characterized in that: the connecting structure includes multiple positioning blocks; multiple first axial square grooves are formed on the outer circumference of the fixing core in the fixing mechanism; multiple second axial square grooves are formed on the inner circumference of the fixing forming wheel in the fixing mechanism; the number of second axial square grooves is equal to the number of first axial square grooves and corresponds one-to-one; the first axial square grooves and the corresponding second axial square grooves form an installation groove for accommodating the positioning blocks; multiple third axial square grooves are formed on the outer circumference of the rotating core in the rotating mechanism; multiple fourth axial square grooves are formed on the inner circumference of the rotating forming wheel in the rotating mechanism; the number of fourth axial square grooves is equal to the number of third axial grooves and corresponds one-to-one; the third axial square grooves and the corresponding fourth axial grooves form an installation groove for accommodating the positioning blocks; the top center positions of the fixing core and the rotating core are connected by a connecting plate; the top center position of the fixing core is hinged to the connecting plate; the output shaft of the servo motor passes through the connecting plate before entering the rotating core.

[0008] The above-mentioned anti-wrinkle precision bending device for thin-walled niobium-zirconium tubes is characterized in that: the outer circumference of the fixed forming wheel and the rotating forming wheel are respectively machined with bending grooves for forming tubes, and the bending grooves on the outer side of the fixed forming wheel and the outer side of the rotating forming wheel constitute the forming groove; the bending grooves include semi-circular grooves for bending round tubes of different specifications and rectangular grooves for bending rectangular tubes of different specifications.

[0009] The above-mentioned anti-wrinkle precision bending device for thin-walled niobium-zirconium tubes is characterized in that: the contact area between the outer surface of the thin-walled tube and the forming groove is coated with a solid lubricating layer. The aforementioned anti-wrinkle precision bending device for thin-walled niobium-zirconium tubes is characterized in that: the solid lubricating layer is a graphite lubricating layer or a molybdenum disulfide lubricating layer.

[0010] The aforementioned anti-wrinkle precision bending device for thin-walled niobium-zirconium tubes is characterized in that the ratio of the outer diameter of the upper and lower end faces of the fixed forming wheel to the outer diameter of the upper and lower end faces of the rotating forming wheel is consistent with the transmission ratio of the fixed gear and the rotating gear.

[0011] The above-mentioned anti-wrinkle precision bending device for thin-walled niobium-zirconium tubes is characterized in that: the clamping mechanism includes a fixed buckle and a movable buckle driven by a cylinder and cooperating with the fixed buckle to clamp the thin-walled tube; and a groove for fitting and installing the fixed buckle is provided on the worktable. This utility model has the following advantages compared with the prior art: 1. This utility model, through its modular wheel design and quick-connect structure of square groove and positioning block, allows for bending of pipes with a wide range of bending radii and various cross-sections simply by changing the fixed forming wheel and rotating forming wheel of different specifications. It is multi-functional, highly efficient, extremely versatile, quick to change molds, and easy to promote and use.

[0012] 2. This utility model provides precise external shaping through the combination of gear transmission and modular wheel set, and provides ultimate internal support through the combination of diamond abrasive filling and plug. The internal and external coordination fundamentally solves the problem of wrinkling and flattening when thin-walled tubes are bent, and has excellent anti-wrinkle and anti-flattening capabilities.

[0013] 3. This utility model adopts servo motor drive and gear ratio transmission, which makes the bending process smooth and precise. The tube cavity is filled with diamond sand as an internal support, and is sealed and pre-compressed by threaded plugs at both ends. The rigidity of the diamond sand internal support is much higher than that of traditional fillers. Combined with precise transmission, it effectively suppresses springback and ensures forming accuracy.

[0014] 4. The external lubrication layer of this utility model effectively prevents scratches on the pipe surface, the internal diamond abrasive has stable chemical properties and is pollution-free, and the plug ensures that the filling material is tight and easy to clean, thus providing comprehensive protection for the high-value niobium-zirconium pipe.

[0015] In summary, this utility model features a novel and reasonable design. It ensures precise bending radius through gear ratio transmission; it enables rapid mold changing for tubes with multiple radii and cross-sections through modular wheel sets; and it combines internal diamond abrasive filling support with external lubrication layer protection to form a synergistic system. This fundamentally solves the problems of wrinkling, flattening, springback, and surface scratches during small-radius bending of thin-walled niobium-zirconium tubes. The structure is reasonable and reliable, comprehensively addressing various defects in the bending of thin-walled niobium-zirconium tubes, improving processing efficiency, and facilitating widespread application.

[0016] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] Figure 2 This is a top view of the initial state of this utility model.

[0019] Figure 3 This is a schematic diagram showing the positional relationship between the forming groove formed by the fixed forming wheel and the rotating forming wheel of this utility model.

[0020] Figure 4 This is a schematic diagram of the fixing mechanism of this utility model.

[0021] Figure 5This is a schematic diagram of the rotating mechanism of this utility model.

[0022] Figure 6 This is a schematic diagram of the clamping mechanism of this utility model.

[0023] Explanation of reference numerals in the attached figures: 1—Workbench; 2—Fixing mechanism; 2-1—Fixing core; 2-2—Fixed gear; 2-3—Fixed forming wheel; 3—Rotating mechanism; 3-1—Rotating core; 3-2—Rotating gear; 3-3—Servo motor; 3-4—Rotating forming wheel; 4—Clamping mechanism; 4-1—Fixing buckle; 4-2—Moving latch; 4-3—Cylinder; 5—Positioning block; 6—Connecting plate; 7—Thin-walled pipe; 8—Forming groove; 9—Plug. Detailed Implementation

[0024] like Figures 1 to 6 As shown, this utility model includes a workbench 1, a clamping mechanism 4 disposed on the workbench 1 for clamping the end of the thin-walled tube 7, and a fixing mechanism 2 and a rotating mechanism 3 disposed on the workbench 1 for anti-wrinkle precision bending of the thin-walled tube 7. The fixing mechanism 2 includes a fixing core 2-1 fixed on the workbench 1 and a fixing gear 2-2 fixedly installed at the bottom of the fixing core 2-1. The fixing forming wheel 2-3 is detachably sleeved on the fixing core 2-1 through a connecting structure. The rotating mechanism 3 includes a servo motor 3-3. The output shaft of the servo motor 3-3 passes through the rotating core 3-1 and is fixedly connected to the rotating core 3-1. The bottom end of the rotating core 3-1 is fixedly installed with a rotating gear 3-2 that meshes with the fixed gear 2-2. The rotating forming wheel 3-4 is detachably sleeved on the rotating core 3-1 through a connecting structure. The thin-walled tube 7 has a support body inside its cavity, and the two ends of the thin-walled tube 7 are provided with plugs 9 for sealing and fastening the support body.

[0025] In this embodiment, the support is a diamond abrasive support.

[0026] It should be noted that through the modular wheel design and the quick-connect structure of the square groove and positioning block, bending of tubes with a wide range of bending radii and various cross-sections can be achieved simply by changing the fixed forming wheel and rotating forming wheel of different specifications. It is multi-purpose, highly efficient, extremely versatile, and quick to change molds. The combination of gear transmission and modular wheel set provides precise external forming, while the combination of diamond abrasive filling and plugs provides ultimate internal support. The internal and external coordination fundamentally solves the problems of wrinkling and flattening in thin-walled tube bending, and has excellent anti-wrinkling and anti-flattening capabilities. The use of servo motor drive and gear ratio transmission ensures a smooth and precise bending process. The tube cavity is filled with diamond abrasive as an internal support, and is sealed and pre-compressed by threaded plugs at both ends. The internal support rigidity of diamond abrasive is much higher than that of traditional fillers. Combined with precise transmission, it effectively suppresses springback and ensures forming accuracy. The external lubrication layer effectively prevents scratches on the tube surface, the internal diamond abrasive is chemically stable and non-polluting, and the plugs ensure that the filler is tight and easy to clean, providing comprehensive protection for the high-value niobium-zirconium tube.

[0027] In this embodiment, the connecting structure includes multiple positioning blocks 5. Multiple first axial square grooves are formed on the outer circumference of the fixing core 2-1 in the fixing mechanism 2. Multiple second axial square grooves are formed on the inner circumference of the fixing forming wheel 2-3 in the fixing mechanism 2. The number of second axial square grooves is equal to and corresponds one-to-one with the number of first axial square grooves. The first axial square grooves and the corresponding second axial square grooves form an installation groove for accommodating the positioning blocks 5. Multiple third axial square grooves are formed on the outer circumference of the rotating core 3-1 in the rotating mechanism 3. Multiple fourth axial square grooves are formed on the inner circumference of the rotating forming wheel 3-4 in the rotating mechanism 3. The number of fourth axial square grooves is equal to and corresponds one-to-one with the number of third axial square grooves. The third axial square grooves and the corresponding fourth axial grooves form an installation groove for accommodating the positioning blocks 5. The top center positions of the fixing core 2-1 and the rotating core 3-1 are connected by a connecting plate 6. The top center position of the fixing core 2-1 is hinged to the connecting plate 6. The output shaft of the servo motor 3-3 passes through the connecting plate 6 before entering the rotating core 3-1.

[0028] In this embodiment, the outer circumferences of the fixed forming wheel 2-3 and the rotating forming wheel 3-4 are respectively machined with bending grooves for forming pipes. The bending grooves on the outer side of the fixed forming wheel 2-3 and the outer side of the rotating forming wheel 3-4 form the forming groove 8. The bending grooves include semi-circular grooves for bending round pipes of different specifications and rectangular grooves for bending rectangular pipes of different specifications.

[0029] In this embodiment, the outer surface of the thin-walled tube 7 and the contact area with the forming groove 8 are coated with a solid lubricating layer. In this embodiment, the solid lubricating layer is a graphite lubricating layer or a molybdenum disulfide lubricating layer, which reduces friction and protects the surface.

[0030] In this embodiment, the ratio of the outer diameter of the upper and lower end faces of the fixed forming wheel 2-3 to the outer diameter of the upper and lower end faces of the rotating forming wheel 3-4 is consistent with the transmission ratio of the fixed gear 2-2 and the rotating gear 3-2, thereby ensuring the accuracy and consistency of the pipe bending radius. By replacing the fixed forming wheel and rotating forming wheel set with different outer diameters and different bending grooves, different bending radii and pipe cross sections (circular, rectangular, etc.) can be quickly adapted.

[0031] In this embodiment, the clamping mechanism 4 includes a fixed buckle 4-1 and a movable buckle 4-2 driven by a cylinder 4-3 and cooperating with the fixed buckle 4-1 to clamp the thin-walled tube 7. The workbench 1 is provided with a groove for fitting and installing the fixed buckle 4-1.

[0032] In use, the fixing core 2-1 in the fixing mechanism 2 has a diameter of 100mm and a thickness of 50mm. Four axially penetrating square grooves of 5mm × 15mm are evenly distributed on its outer circumference. A fixing gear 2-2 is fixed to one end of the fixing core 2-1 via a key connection. The fixing forming wheel (different specifications of fixing forming wheel 2-3 are selected according to requirements) has an inner diameter of 100mm, an outer diameter designed according to the target bending radius (range from 200mm to 800mm), and a thickness of 50mm. Four 5mm × 15mm square grooves are also evenly distributed on its inner circumference. Circumferential positioning and torque transmission are achieved by embedding four 5mm × 15mm × 50mm positioning blocks 5 into the corresponding square grooves of the fixing core 2-1 and the fixing forming wheel, respectively. In the rotating mechanism 3, the rotating core 3-1 has a diameter of 50mm and a thickness of 50mm. Four square grooves are evenly distributed on its outer circumference. A rotating gear 3-2 is fixed to one end of the rotating core 3-1, and its meshing transmission ratio with the fixed gear 2-2 is 2:1. The rotating forming wheel 3-4 is mounted on the rotating core 3-1 in the same manner via the positioning block 5. The servo motor 3-3 drives the rotating mechanism 3 to rotate as a whole through a reducer. The outer diameter ratio between the fixed forming wheel and the rotating forming wheel is strictly maintained at 2:1, consistent with the gear transmission ratio, to ensure the correctness of the bending geometry. The thin-walled tube 7 (taking a 32mm diameter niobium-zirconium tube as an example) is filled with a dry and clean diamond support. Both ends of the tube are sealed by plugs 9, and the diamond support inside the tube is pre-compressed by plugs 9 so that it is in a tight state before bending. Graphite lubricant is uniformly coated on the outer surface of the area to be bent in the thin-walled tube 7. The tube is placed in the grooves of the fixed forming wheel and the rotating forming wheel, so that the middle part is tightly attached to the fixed forming wheel and the end is clamped on the rotating forming wheel by the clamping mechanism 4. Start the servo motor 3-3 to drive the rotating mechanism 3 to rotate around the fixed mechanism 2. Under the precise guidance of the gear ratio transmission and modular wheel set, the tube is bent around the fixed forming wheel to a predetermined radius. The compacted diamond grit inside provides ultimate internal support, effectively preventing wrinkles and flattening. After bending to a predetermined angle (e.g., 180°), the motor stops, the clamping mechanism releases, and the workpiece is removed. Unscrew the end caps 9 at both ends and pour out the diamond abrasive 8 (which is recyclable), resulting in a high-precision bent tube.

[0033] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the present utility model. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the present utility model shall still fall within the protection scope of the present utility model.

Claims

1. A precision tube bending device for thin-walled niobium-zirconium tubes, characterized in that: It includes a worktable (1), a clamping mechanism (4) set on the worktable (1) for clamping the end of the thin-walled tube (7), and a fixing mechanism (2) and a rotating mechanism (3) set on the worktable (1) for anti-wrinkle precision bending of the thin-walled tube (7). The fixing mechanism (2) includes a fixing core (2-1) fixed on the workbench (1) and a fixing gear (2-2) fixedly installed at the bottom of the fixing core (2-1). The fixing forming wheel (2-3) is detachably sleeved on the fixing core (2-1) through a connecting structure. The rotating mechanism (3) includes a servo motor (3-3), the output shaft of which passes through the rotating core (3-1) and is fixedly connected to the rotating core (3-1). The bottom end of the rotating core (3-1) is fixedly installed with a rotating gear (3-2) that meshes with the fixed gear (2-2). The rotating forming wheel (3-4) is detachably sleeved on the rotating core (3-1) through a connecting structure. The thin-walled tube (7) is filled with a support body, and the two ends of the thin-walled tube (7) are provided with plugs (9) for sealing and fastening the support body.

2. The anti-wrinkle precision bending device for thin-walled niobium-zirconium tubes according to claim 1, characterized in that: The support is a diamond support.

3. The anti-wrinkle precision tube bending device for thin-walled niobium-zirconium tubes according to claim 1, characterized in that: The connecting structure includes multiple positioning blocks (5). In the fixing mechanism (2), multiple first axial square grooves are formed on the outer circumference of the fixing core (2-1), and multiple second axial square grooves are formed on the inner circumference of the fixing forming wheel (2-3). The number of second axial square grooves is equal to and corresponds one-to-one with the number of first axial square grooves. The first axial square grooves and the corresponding second axial square grooves form an mounting groove for accommodating the positioning blocks (5). In the rotating mechanism (3), multiple third axial square grooves are formed on the outer circumference of the rotating core (3-1). Multiple fourth axial square grooves are opened on the inner circumference of the rotating forming wheel (3-4). The number of fourth axial square grooves is equal to the number of third axial square grooves and corresponds one-to-one. The third axial square groove and the corresponding fourth axial square groove form an installation groove for accommodating the positioning block (5). The top center positions of the fixed core (2-1) and the rotating core (3-1) are connected by a connecting plate (6). The top center position of the fixed core (2-1) is hinged to the connecting plate (6). The output shaft of the servo motor (3-3) passes through the connecting plate (6) before entering the rotating core (3-1).

4. A precision tube bending device for thin-walled niobium-zirconium tubes according to claim 1, characterized in that: The fixed forming wheel (2-3) and the rotating forming wheel (3-4) are respectively machined with bending grooves for forming pipes. The bending grooves on the outside of the fixed forming wheel (2-3) and the bending grooves on the outside of the rotating forming wheel (3-4) form a forming groove (8). The bending grooves include semi-circular grooves for bending round pipes of different specifications and rectangular grooves for bending rectangular pipes of different specifications.

5. A precision tube bending device for thin-walled niobium-zirconium tubes according to claim 4, characterized in that: The outer surface of the thin-walled tube (7) and the contact area with the forming groove (8) are coated with a solid lubricating layer.

6. A precision tube bending device for thin-walled niobium-zirconium tubes according to claim 5, characterized in that: The solid lubricating layer is a graphite lubricating layer or a molybdenum disulfide lubricating layer.

7. A precision tube bending device for thin-walled niobium-zirconium tubes according to claim 1, characterized in that: The ratio of the outer diameter of the upper and lower end faces of the fixed forming wheel (2-3) to the outer diameter of the upper and lower end faces of the rotating forming wheel (3-4) is consistent with the transmission ratio of the fixed gear (2-2) and the rotating gear (3-2).

8. A precision tube bending device for thin-walled niobium-zirconium tubes according to claim 1, characterized in that: The clamping mechanism (4) includes a fixed buckle (4-1) and a movable buckle (4-2) driven by a cylinder (4-3) and cooperating with the fixed buckle (4-1) to clamp the thin-walled tube (7). The workbench (1) has a groove for fitting and installing the fixed buckle (4-1).

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