Shaping die for rolled and welded metal plate

Abstract

The utility model provides a shaping die for rolled and welded metal plates, and belongs to the field of shaping dies. The shaping die for the rolled and welded metal plate comprises an inner die and an outer die, the outer die comprises at least two expansion die bodies arranged in the circumferential direction, the outer side faces of the expansion die bodies in the radial direction form shaping faces used for jacking and supporting a workpiece from the interior of the workpiece in the radial direction, and the inner side faces of the expansion die bodies in the radial direction are inner conical faces; the inner mold is provided with an outer conical surface which is matched with the inner conical surface after the inner mold is inserted into the outer mold, and a tensioning mechanism which is used for applying force to the outer mold and the inner mold in the axial direction so as to tension the outer mold and the inner mold is arranged between the outer mold and the inner mold. According to the shaping die, the tensioning mechanism is arranged between the inner die and the outer die, so that a workpiece can be kept in a supported circle state for a long time, and the application range of the shaping die is expanded.

Description

Technical Field

[0001] The utility model belongs to the field of shaping dies, in particular to a shaping die for rolled and welded metal plates. Background Art

[0002] Large cylindrical metal workpieces can be formed by stamping or by rolling and welding the metal sheet. Welding has gained widespread application due to its advantages of high material utilization, low equipment requirements, and simple processing. However, due to the precision limitations of rolling machines, curved structures cannot be formed at either end of the metal sheet, resulting in a flat weld seam on the welded workpiece. Thermal deformation of the metal sheet during welding can also result in the workpiece not being a perfect circle. Products requiring high roundness require post-weld shaping using specialized molds.

[0003] Typically, a cylindrical shaping die is used. During shaping, the die is pressed into the workpiece using a pressure gauge. The workpiece is then shaped and rounded using an interference fit. Once shaping is complete, the die is removed from the workpiece. The outer dimensions of the die are comparable to the inner dimensions of the workpiece after shaping. Therefore, both inserting and removing the die are difficult, resulting in low shaping efficiency. Furthermore, a single-size die can only shape workpieces of one size. If multiple workpiece sizes are involved in the production process, multiple dies of different sizes are required, resulting in low mold versatility and high production costs.

[0004] The existing Chinese utility model patent with authorization announcement number CN202655394U discloses an internal expansion type shaping structure, which is used to shape the inner surface of a circular hole on a workpiece, and can also be used to shape the workpiece after metal plate rolling and welding. The shaping structure includes an expansion pin and an expansion block. The expansion pin is a conical pin. The expansion block is composed of three identical radian blocks arranged and assembled along the circumferential direction. The radial inner side surface of the assembled expansion block is an inner conical surface for cooperating with the outer conical surface of the expansion pin, and the radial outer side surface is a cylindrical surface. When in use, the expansion block is assembled in the hole of the workpiece, and then the expansion pin is inserted, and the expansion pin and the expansion block are moved relative to each other in the axial direction, so that the radian blocks of the expansion block can be moved outward to make the workpiece round. Disassembly and installation are relatively convenient, which can improve the shaping efficiency, and can adapt to workpieces of different sizes within a certain range, thereby improving the versatility of the mold.

[0005] However, some workpieces need to be kept in the rounded shape for a long time, especially some special materials need to be annealed with a mold to eliminate the internal stress of the material. However, as long as the outside world no longer applies force to the axial ends of the inner mold (i.e., the expanding pin) and the outer mold (i.e., the expanding block), the inner mold and the outer mold will easily detach from each other and cannot be stably maintained in the required state when the workpiece is rounded. Therefore, the scope of application of this shaping structure is limited. Utility Model Content

[0006] The purpose of the utility model is to provide a shaping die for metal plates after rolling and welding, so as to solve the technical problem that the shaping die in the prior art cannot be kept in a required state for a long time and thus has a small scope of application.

[0007] To achieve the above-mentioned purpose, the technical solution of the shaping die after metal plate rolling and welding provided by the present invention is:

[0008] A shaping die for metal plates after rolling and welding, comprising an inner die and an outer die, the outer die comprising at least two expansion die bodies arranged circumferentially, the radial outer side surfaces of the expansion die bodies constituting a shaping surface for radially supporting the workpiece from the inside of the workpiece, the radial inner side surfaces of the expansion die bodies being inner conical surfaces, the inner die being provided with an outer conical surface for cooperating with the inner conical surface after the inner die is inserted into the outer die, and a tensioning mechanism being provided between the outer die and the inner die for applying axial force to the outer die and the inner die to tighten the outer die and the inner die.

[0009] As a further improvement, the tensioning mechanism includes a bottom pad for press-fitting with the axial end face of one of the outer mold and the inner mold, and a top pad for press-fitting with the axial end face of the other mold. A fastener for tightening the bottom pad and the top pad is provided between the bottom pad and the top pad, and a through hole is provided axially through the inner mold for the fastener to pass through.

[0010] As a further improvement, the fasteners include fastening bolts and fastening nuts, and both the bottom plate and the top plate are provided with connecting holes for the fastening bolts to pass through.

[0011] As a further improvement, the bottom pad is press-fitted with the axial end face of the outer mold, and the top pad is press-fitted with the axial end face of the inner mold.

[0012] As a further improvement, the middle position of the bottom plate constitutes a mold supporting area for supporting the outer mold, and the edge position of the bottom plate constitutes a workpiece supporting area for supporting the workpiece.

[0013] As a further improvement, the outer diameter of the top pad is larger than the inner diameter of the perforation and smaller than the outer diameter of the large end of the inner mold.

[0014] As a further improvement, the tensioning mechanism includes an end pad for press-fitting with the axial end face of the outer mold, and also includes a connecting piece connected between the small end of the inner mold and the end pad and used to axially tighten the inner mold and the end pad, and a through hole is provided on the end pad for the connecting piece to pass through.

[0015] As a further improvement, the connecting piece includes a threaded rod fixedly connected to the end face of the small end of the inner mold, and a clamping nut for clamping the end pad is connected to the threaded rod.

[0016] As a further improvement, the large end of the inner mold is provided with a hoisting structure for connecting to a hoisting device.

[0017] As a further improvement, the lifting structure includes an annular convex edge located at the large end of the inner mold, and at least two lifting holes arranged along the circumferential direction are axially opened on the convex edge, and at least one lifting hole is a threaded hole.

[0018] The beneficial effect is that the post-rolling and welding shaping die provided by the present invention is an improvement over the prior art. In the post-rolling and welding shaping die, the inner and outer dies cooperate with each other via an outer conical surface and an inner conical surface. During the relative axial movement of the inner and outer dies, the expanded die bodies of the outer die are subjected to a radially outward force and thus move radially outward, thereby rounding a workpiece encased outside the outer die. Furthermore, the inner and outer dies can be maintained in the rounded state by a tensioning mechanism, facilitating other processing of the workpiece, thus extending the application range of the shaping die. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the overall structure of Example 1 of the shaping die after metal plate rolling and welding in the present invention;

[0020] Figure 2 This is a cross-sectional view of the inner mold of Example 1 of the shaping mold after metal plate rolling and welding in the present invention;

[0021] Figure 3 A top view of the outer mold of Example 1 of the shaping mold after metal plate rolling and welding in the present invention;

[0022] Figure 4 This is a cross-sectional view of the outer mold of Example 1 of the shaping mold after metal plate rolling and welding in the present invention;

[0023] Figure 5 This is a cross-sectional view of the expanded die body of Example 1 of the shaping die after metal plate rolling and welding in the present invention;

[0024] Figure 6 This is a cross-sectional view of the bottom plate of Example 1 of the shaping die after metal plate rolling and welding in the present invention;

[0025] Figure 7 This is a schematic diagram of the overall structure of Example 4 of the shaping die after metal plate rolling and welding in the present invention.

[0026] Description of reference numerals:

[0027] 1. Inner mold; 2. Outer mold; 21. Expansion mold body; 22. Shaping surface; 23. Inner conical surface; 3. Bottom plate; 4. Top plate; 5. Fastening bolts; 6. Fastening nuts; 7. Workpiece; 8. Through hole; 9. Connecting hole; 10. Flange; 11. Lifting hole; 12. End plate; 13. Threaded rod; 14. Pressing nut. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below with reference to the embodiments.

[0029] In order to solve the problems in the existing technology, the basic concept of the present invention is that after the shaping mold rounds the workpiece, a tensioning mechanism is used to apply force to both ends of the outer mold and the inner mold to keep the shaping mold in the required state, thereby expanding the scope of application of the shaping mold.

[0030] Specific embodiment 1 of the shaping die for metal plate after rolling and welding provided by the utility model:

[0031] A shaping die for metal sheets after rolling and welding, see attached Figure 1 , including an inner mold 1, an outer mold 2, and a tensioning mechanism arranged between the inner mold 1 and the outer mold 2.

[0032] See attached Figure 2 The inner mold 1 is in the shape of a truncated cone, and the large end of the inner mold 1 is provided with a lifting structure for connecting to a lifting equipment. The lifting structure can facilitate the lifting of the inner mold 1, or the lifting of the entire plastic mold. The lifting structure includes an annular flange 10 located at the large end of the inner mold 1, and a plurality of lifting holes 11 are axially penetrated on the flange 10. The lifting holes 11 are evenly distributed along the circumference of the flange 10. The lifting holes 11 are all threaded holes, and lifting rings can be installed in the lifting holes 11 to facilitate the connection of the lifting equipment to the inner mold 1 for lifting operations. In other embodiments, the lifting holes can also be partially threaded holes for installing lifting rings, and the other part can be used as weight-reducing holes or as holes for connecting ropes.

[0033] See attached Figure 3 , Attachment Figure 4 and attached Figure 5 The outer mold 2 includes three circumferentially arranged expansion mold bodies 21. The radially outer side surfaces of the expansion mold bodies 21 constitute shaping surfaces 22, and the radially inner side surfaces of the expansion mold bodies 21 constitute inner conical surfaces 23. When the three expansion mold bodies 21 are joined together, an annular outer mold 2 is formed. The shaping surfaces 22 of the expansion mold bodies 21 constitute the outer circumferential surface of the outer mold 2, while the inner conical surfaces 23 of the expansion mold bodies 21 constitute the inner wall of the center hole of the outer mold 2. Therefore, the center hole of the outer mold 2 is a tapered hole.

[0034] The tensioning mechanism includes a bottom plate 3 and a top plate 4, and also includes a fastener disposed between the bottom plate 3 and the top plate 4 for tensioning the bottom plate 3 and the top plate 4. Figure 6 The bottom plate 3 and the top plate 4 are both circular plates, and a circular connecting hole 9 is opened at the center position of the bottom plate 3 and the top plate 4.

[0035] The fasteners include a fastening bolt 5 and a fastening nut 6. A through hole 8 for the fastening bolt 5 to pass through is axially provided at the center position of the inner mold 1. The fastening bolt 5 first passes through the connecting hole 9 on the bottom pad 3, then passes through the through hole 8, and finally passes through the bolt hole on the top pad 4 and is connected to the fastening nut 6. By tightening the fastening nut 6, the top pad 4 and the bottom pad 3 can be tightened.

[0036] When in use, first pass the fastening bolt 5 through the connecting hole 9 on the bottom pad 3, then make the tail of the fastening bolt 5 face upwards and place the bottom pad 3 on the operating platform; then place the workpiece 7 to be shaped on the bottom pad 3, put the expansion mold bodies 21 one by one into the inner side of the workpiece 7, and splice them into a complete outer mold 2, and the large mouth of the center hole of the outer mold 2 faces upwards; then insert the small end of the inner mold 1 downward into the center hole of the outer mold 2, and at the same time pass the fastening bolt 5 through the through-hole 8; finally, place the top pad 4 on the end face of the large end of the outer mold 2, and at the same time pass the fastening bolt 5 through the bolt hole on the top pad 4, and then connect the fastening nut 6 with the fastening bolt 5.

[0037] The operator tightens the fastening nut 6. As the fastening nut 6 is tightened, the top and bottom plates 4 and 3 are subjected to axial tension, causing them to approach each other, thereby moving the inner die 1 downward. The outer conical surface of the inner die 1 cooperates with the inner conical surfaces 23 of each expansion die body 21, converting the downward movement of the inner die 1 into radially outward movement of each expansion die body 21. The shaping surfaces 22 of each expansion die body 21 radially support the workpiece 7 from the inside, making the workpiece 7 increasingly round.

[0038] After the shape of the workpiece 7 meets the use requirements, the tightening operation is stopped. The shaping mold can always be kept in the state after the workpiece is rounded. For workpieces 7 made of some special materials, the mold can be annealed together to eliminate internal stress. After that, the shaping mold can be disassembled to obtain a workpiece 7 with a shape that meets the requirements. The disassembly process of the shaping mold is the reverse process of the above-mentioned process, that is, after loosening the fastening nut 6, remove the top plate 4, and then remove the inner mold 1. Since the inner mold 1 and the outer mold 2 are matched through a conical surface, the inner mold 1 can be lifted up to loosen it from the outer mold 2 and then it can be smoothly taken out, and the difficulty of taking it out is relatively low. After the inner mold 1 and the outer mold 2 are loosened, each expansion mold body 21 no longer supports the workpiece 7, so each expansion mold body 21 can also be smoothly taken out.

[0039] For workpieces 7 that are larger in size or have thicker walls, if the operator cannot successfully round the workpiece 7 by manpower, a pressure gauge can be used to press down the top pad, thereby moving the inner mold 1 downward to achieve rounding of the workpiece 7. After the rounding is completed, the tensioning mechanism can be used to tighten the inner mold 1 and the outer mold 2.

[0040] Compared with the prior art, the shaping mold in this embodiment is, on the one hand, simple to assemble and disassemble, more efficient, can be used without a press, and more flexible; on the other hand, the shaping mold can adapt to a variety of workpieces 7 of different diameters in a small range, thereby improving the utilization rate of the shaping mold and reducing production costs. Specifically, when the diameter of the workpiece 7 to be shaped is larger, the downward movement distance of the inner mold 1 is larger and the radial movement distance of the expansion mold body 21 is larger. When the diameter of the workpiece 7 to be shaped is smaller, the downward movement distance of the inner mold 1 is smaller and the radial movement distance of the expansion mold body 21 is smaller.

[0041] In order to reduce the overall weight of the inner mold 1 and facilitate transportation, the diameter of the through hole 8 on the inner mold 1 for the fastening bolt 5 to pass through can be enlarged so that the through hole 8 can also play a role in reducing weight.

[0042] The top plate 4 serves only to transmit force between the inner mold 1 and the fastening nut 6. Its diameter can meet the requirements as long as it is larger than the diameter of the through hole 8. Therefore, the diameter of the top plate 4 can be smaller, specifically smaller than the outer diameter of the large end of the inner mold 1, that is, the outer diameter of the flange 10, to save material. Furthermore, the diameter of the top plate 4 must be sufficient to avoid the lifting ring installed in the lifting hole 11, so as to facilitate the lifting of the workpiece 7 and the shaping mold as a whole when the workpiece 7 is rounded.

[0043] The bottom plate 3 not only plays the role of transmitting force between the outer mold 2 and the fastening bolts 5, but also plays the role of supporting each expansion mold body 21 and the workpiece 7. Therefore, the diameter of the bottom plate 3 needs to be larger. Specifically, the diameter of the bottom plate 3 needs to be larger than the diameter of the workpiece 7 with the maximum diameter that can be shaped by the shaping mold. The middle position of the bottom plate 3 constitutes a mold support area for supporting the outer mold 2, and the edge position of the bottom plate 3 constitutes a workpiece 7 support area for supporting the workpiece 7. This makes it easier to align the end face of the workpiece 7 with the end face of the outer mold 2.

[0044] Of course, in other embodiments, the size or shape of the top pad and the bottom pad can be set according to actual needs, which will not be elaborated here.

[0045] In other implementations of this embodiment, the fasteners may also only include fastening bolts. In this implementation, internal threads can be processed in the connecting holes on the bottom pad, and the fastening bolts can pass through the connecting holes on the top pad from top to bottom, through the through holes on the inner mold, and finally engage with the connecting holes on the bottom pad. Tightening the fastening bolts can tighten the bottom pad and the top pad. In this implementation, holes or grooves need to be reserved on the operating platform to avoid the fastening bolts.

[0046] In another embodiment, the lifting hole can also be a through hole, which can be connected to a rope to connect the lifting equipment to the inner membrane. In other embodiments, the lifting structure can also be a connecting ring welded and fixed on the large end edge of the inner mold to facilitate connection with the lifting equipment via a rope or hook.

[0047] In this embodiment, the convex edge and the lifting hole are provided to facilitate lifting the inner mold when the inner mold is heavy. When the inner mold is light, the convex edge and the lifting hole may not be provided.

[0048] Specific embodiment 2 of the shaping die after metal plate rolling and welding provided by the utility model:

[0049] This embodiment is based on embodiment 1, and differs from embodiment 1 in that, in this embodiment, the small end of the inner mold faces upward, and the large opening of the outer mold faces downward.

[0050] During use, after the bottom plate is in place, the inner mold is placed on the bottom plate with the large end facing downward and the small end facing upward. The workpiece is then placed over the inner mold, with the upper surface of the ridge on the inner mold supporting the workpiece. Expanding mold bodies are then inserted into the annular space between the inner mold and the workpiece until the expanded mold bodies form the completed outer mold. Finally, the top plate is installed, and the nuts are tightened to allow the expanding mold bodies to move downward. As they move downward, they also move radially outward, thus rounding the workpiece.

[0051] Specific embodiment 3 of the shaping die after metal plate rolling and welding provided by the utility model:

[0052] This embodiment is based on embodiment 1, and differs from embodiment 1 in that the fastener of the tensioning mechanism in this embodiment is a threaded rod welded and fixed on the bottom plate, and the threaded rod is still connected to a fastening nut.

[0053] Specific embodiment 4 of the shaping die after metal plate rolling and welding provided by the utility model:

[0054] This embodiment is based on embodiment 1, and the difference from embodiment 1 is that, see attached Figure 7 In this embodiment, the small end of the inner mold 1 is facing upward and the large end of the outer mold 2 is facing downward.

[0055] In this embodiment, the bottom pad 3 and the top pad 4 are no longer provided, and the tensioning structure includes an end pad 12 for press-fitting with the axial end face of the outer mold 2. The tensioning structure also includes a connector connected between the small end of the inner mold 1 and the end pad 12 and used to axially tighten the inner mold 1 and the end pad 12. The connector is specifically a threaded rod 13 fixedly provided on the end face of the small end of the inner mold 1. A through hole for the threaded rod 13 to pass through is provided on the end pad 12. After the end pad 12 is put on the threaded rod 13 and placed on the end face of the small end of the inner mold 1, a clamping nut 14 is installed on the threaded rod 13. Tightening the clamping nut 14 can make the end pad 12 press down each expansion mold body 21, thereby making the workpiece 7 round.

[0056] Specific embodiment 5 of the shaping die for metal plate after rolling and welding provided by the utility model:

[0057] This embodiment is based on embodiment 4, and differs from embodiment 4 in that the connecting piece in this embodiment is specifically a clamping bolt, and a threaded hole for threaded cooperation with the clamping bolt is provided on the end face of the small end of the inner mold 1. After the clamping bolt passes through the through hole on the end pad, it is installed in the threaded hole. Tightening the clamping bolt can tighten the inner mold and the end pad, and then tighten the inner mold and the outer mold along the axial direction.

[0058] Specific embodiment 6 of the shaping die for metal plates after rolling and welding provided by the present invention:

[0059] This embodiment is based on embodiment 1, and differs from embodiment 1 in that, in this embodiment, no holes are opened on the top pad and the bottom pad, a screw is fixedly connected to the top pad, and a threaded barrel for cooperating with the screw thread is fixedly connected to the bottom pad. When in use, the screw is screwed into the threaded barrel, and the operator can rotate the top pad to screw the screw into the threaded barrel.

[0060] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments without inventive effort, or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. 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 shaping die for metal sheets after rolling and welding, comprising an inner die and an outer die, wherein the outer die comprises at least two circumferentially arranged expansion die bodies, wherein the radially outer side surfaces of the expansion die bodies constitute shaping surfaces for radially supporting the workpiece from the inside of the workpiece, and the radially inner side surfaces of the expansion die bodies are inner conical surfaces, and the inner die is provided with an outer conical surface for mating with the inner conical surface after the inner die is inserted into the ... radially inner side surfaces of the expansion die bodies are inner conical surfaces, and the radially inner side surfaces of the expansion die bodies are inner conical surfaces, and the radially inner side surfaces of the expansion die bodies are inner conical surfaces, and the radially inner side surfaces of the expansion die bodies are inner conical surfaces, and the radially inner side surfaces of the expansion die bodies are inner conical surfaces, and the radially inner side surfaces of the expansion die bodies are inner conical surfaces, and the radially inner side surfaces of the expansion die bodies are inner conical A tensioning mechanism is provided between the outer mold and the inner mold for applying axial force to the outer mold and the inner mold to tighten the outer mold and the inner mold.

2. The shaping die for metal plates after rolling and welding according to claim 1, characterized in that: The tensioning mechanism includes a bottom plate for press-fitting with the axial end face of one of the outer mold and the inner mold, and a top plate for press-fitting with the axial end face of the other mold. A fastener for tightening the bottom plate and the top plate is provided between the bottom plate and the top plate, and a through hole for the fastener to pass through is provided axially through the inner mold.

3. The shaping die for metal plates after rolling and welding according to claim 2, characterized in that: The fasteners include fastening bolts and fastening nuts, and the bottom plate and the top plate are both provided with connection holes for the fastening bolts to pass through.

4. The shaping die for metal plates after rolling and welding according to claim 2 or 3, characterized in that: The bottom pad is press-fitted with the axial end face of the outer mold, and the top pad is press-fitted with the axial end face of the inner mold.

5. The shaping die for metal plates after rolling and welding according to claim 4, characterized in that: The middle position of the bottom plate constitutes a mold supporting area for supporting the outer mold, and the edge position of the bottom plate constitutes a workpiece supporting area for supporting the workpiece.

6. The shaping die for metal plates after rolling and welding according to claim 4, characterized in that: The outer diameter of the top pad is larger than the inner diameter of the perforation and smaller than the outer diameter of the large end of the inner die.

7. The shaping die for metal plates after rolling and welding according to claim 1, characterized in that: The tensioning mechanism includes an end pad for press-fitting with the axial end face of the outer mold, and also includes a connecting piece connected between the small end of the inner mold and the end pad and used to axially tighten the inner mold and the end pad. A through hole is provided on the end pad for the connecting piece to pass through.

8. The shaping die for metal plates after rolling and welding according to claim 7, characterized in that: The connecting piece comprises a threaded rod fixedly connected to the end surface of the small end of the inner mold, and a compression nut for compressing the end pad is connected to the threaded rod.

9. The shaping die for metal plates after rolling and welding according to any one of claims 1 to 3, characterized in that: The large end of the inner mold is provided with a hoisting structure for connecting with a hoisting device.

10. The shaping die for metal plates after rolling and welding according to claim 9, characterized in that: The hanging structure comprises an annular convex edge located at the large end of the inner mold, and at least two hanging holes arranged along the circumferential direction are axially opened on the convex edge, and at least one hanging hole is a threaded hole.

Images