Active non-uniform loading pipe push-bending forming device
By using an active non-uniform loading tube bending forming device, the defects in the forming of thin-walled tubes with small bending radii are solved by utilizing the combined boundary conditions of temperature difference, thrust and friction, achieving high-quality and efficient forming results.
Patent Information
- Application Number
- CN202520049498.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-09
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-01-09
AI Technical Summary
Traditional methods are difficult to effectively form thin-walled tubes with small bending radii, and are prone to defects such as instability and wrinkling, excessive thinning and cross-sectional distortion. The forming difficulty increases, especially under conditions of small bending radius and thin wall thickness.
An active non-uniform loading tube bending forming device is adopted. Non-uniform loading is achieved through a combination of boundary conditions of different temperature, different thrust and different friction, including a bending die with heating rod inlet and cooling groove, controllable inner and outer punches and inner and outer lubricants.
It improves the quality of thin-walled tube bending, suppresses wrinkling and excessive thinning defects, increases the forming limit, enhances operability, and is suitable for a variety of metal materials.
Smart Images
Figure CN223819409U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of metal tube bending and forming technology, specifically to an active non-uniform loading tube bending and forming device. Background Technology
[0002] Thin-walled tube bending technology is an important manufacturing technology in the field of material plastic processing. Thin-walled bent tubes are widely used in aerospace, aviation, automotive, shipbuilding and other transportation equipment, as well as chemical, construction and other fields. When forming thin-walled tubes with small bending radii, traditional methods are difficult to meet the forming requirements. Under the constraints of various molds, the stress and strain states of thin-walled tubes during bending are relatively complex, which can easily lead to defects such as instability and wrinkling, excessive thinning, and cross-sectional distortion. As the wall thickness of the bent tube decreases (relative wall thickness, the ratio of wall thickness to the outer diameter of the tube ≤ 0.02) and the bending radius decreases (relative bending radius, i.e., the ratio of bending radius to the outer diameter of the tube ≤ 1.5), the bending difficulty increases. Utility Model Content
[0003] In order to overcome the shortcomings of the prior art, the purpose of this utility model is to provide an active non-uniform loading pipe bending forming device, a pipe bending forming device that facilitates adjustment of differential loading combination mode, which involves a bending forming device that facilitates adjustment of differential temperature, differential thrust, and differential friction.
[0004] To solve the above-mentioned technical problems, this utility model provides the following technical solution:
[0005] An active non-uniform loading tube bending forming device includes a bending die with a heating rod inlet and a cooling groove, an inner punch and an outer punch whose movements can be controlled separately, and a tube blank to be bent with a filler in the inner cavity and the same or different types of lubricant applied to both sides of the bending section.
[0006] The active non-uniform loading pipe bending forming device has a heating rod insertion port on one side of the bending mold and a cooling groove on the other side of the bending mold.
[0007] The active non-uniform loading pipe bending forming device has heating rod inlets located outside the bending section of the bending die, with two or more sets of heating rod inlets and heating rods installed inside the heating rod inlets; a cooling tank is provided inside the bending section of the bending die, and the cooling tank is filled with coolant.
[0008] The active non-uniform loading pipe bending forming device has guide sleeves installed at both ends of the bending die by bolts, and the inner hole of each guide sleeve is connected to one port of the bending die cavity.
[0009] The active non-uniform loading pipe bending forming device has a guide sleeve at one end of the bending die, in which the pipe blank to be bent is installed and slides in fit with the pipe blank. The outer port of the guide sleeve is the feed end of the punch, and the feed end of the guide sleeve is provided with an inner punch and an outer punch that slide relative to each other.
[0010] The active non-uniform loading pipe bending forming device has a guide sleeve inner hole at the other end of the bending die as the output end of the bent pipe.
[0011] The active non-uniform loading tube bending forming device has the inner and outer sides of the bending section of the tube blank to be bent as the inner and outer sides of the tube blank, respectively, and the same or different types of lubricant are applied to the inner and outer sides of the tube blank.
[0012] The active non-uniform loading pipe bending forming device fills the inner cavity of the pipe blank to be bent with filler and places it in the guide sleeve, and welds a plug to the front end of the pipe blank to be bent.
[0013] The design concept of this utility model is:
[0014] This invention improves the uniformity of deformation on both the inner and outer sides of the pipe during the bending process by actively and selectively applying various non-uniform boundary conditions, thereby suppressing defects. These non-uniform boundary conditions include differential temperature, differential thrust, and differential friction loading, and are combinations of two or three of these conditions during the forming process. The active and selective application of these non-uniform boundary conditions during the bending process is achieved through the design of the bending die structure and the pretreatment of the pipe blank.
[0015] (1) Differential temperature is achieved by designing a bending mold with heating rod inlets and cooling tanks. The outer side of the bending section of the bending mold cavity is provided with heating rod inlets, and the inner side of the bending section is provided with cooling tanks. The heating rod inlets are mainly located on the outer side of the bending section of the bending mold cavity, and multiple sets of heating rod inlets are set. Differential temperature adjustment is achieved by the temperature of the heating rods and the flow rate of the cooling liquid in the cooling tank.
[0016] (2) Differential thrust is achieved by the inner punch and the outer punch, which can be controlled separately. The inner punch and the outer punch are set at the feed end port of the bending die cavity and are controlled independently. Differential thrust adjustment is achieved by applying different thrusts to the inner punch and the outer punch.
[0017] (3) Differential friction is achieved by using a tube blank with different internal fillers and external lubrication. The tube blank is divided into two regions on the inner and outer sides of the bending section. Different lubricants are used in the inner and outer regions to achieve different lubrication coefficients on the inner and outer sides of the bending section. Differential friction is adjusted by changing the lubricant.
[0018] The advantages and beneficial effects of this utility model are:
[0019] 1. This utility model forming device integrates the advantages of differential temperature, differential thrust, and differential friction coefficient. Differential temperature increases the material flowability on the outer side of the bend, reducing tearing, while increasing the stiffness on the inner side, reducing wrinkling. Differential thrust increases the outer thrust, reducing thinning on the outer side, and decreases the inner thrust, reducing the risk of wrinkling on the inner side. Differential friction improves material flow, further reducing the risk of wrinkling. Compared to a single differential loading process, it can further improve the forming quality of the pipe, adjust the stress during the bending process of thin-walled pipes, prevent instability, wrinkling, and excessive thinning defects during the forming process of thin-walled pipes with small bending radii, and improve the forming limit of pipe bending.
[0020] 2. The forming device of this utility model applies composite active non-uniform boundary conditions, which is highly operable and easy to implement.
[0021] 3. The forming device of this utility model can form metal and alloy materials such as steel, aluminum, and copper. Attached Figure Description
[0022] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:
[0023] Figure 1 This is a schematic diagram of the present invention before molding;
[0024] Figure 2 This is a schematic diagram of the formed product of this utility model.
[0025] In the figure, 1 is the bending die, 2 is the heating rod insertion port, 3 is the cooling tank, 4 is the inner punch, 5 is the outer punch, 6 is the tube blank to be bent (6-1 inner side of the tube blank, 6-2 outer side of the tube blank, 6-3 plug), 7 is the filler, 8 is the guide sleeve, and 9 is the bend (9-1 inner side of the bend, 9-2 outer side of the bend). Detailed Implementation
[0026] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention. The present invention can be implemented in many different ways as defined and covered by the claims.
[0027] Example 1:
[0028] like Figures 1-2As shown, this utility model provides an active non-uniform loading push-bending forming device that combines two or three differential loadings of differential temperature, differential thrust, and differential lubrication. By actively and selectively applying multiple non-uniform boundary conditions to the inner and outer sides of the pipe during the push-bending process, the uniformity of deformation on the inner and outer sides of the bent pipe is improved, thereby achieving defect suppression.
[0029] like Figure 1 As shown, the active non-uniform loading pipe bending forming device of this utility model includes a bending mold 1 with a heating rod inlet 2 and a cooling groove 3, an inner punch 4 and an outer punch 5 whose movements can be controlled separately, and a pipe blank 6 to be bent with a filler 7 in the inner cavity and the same or different types of lubricating liquid applied to both sides of the bending section.
[0030] A heating rod insertion port 2 is provided on one side of the bending die 1, and a cooling groove 3 is provided on the other side of the bending die 1. Guide sleeves 8 are respectively installed at both ends of the bending die 1 by bolts. The inner hole of each guide sleeve 8 is connected to one port of the cavity of the bending die 1. The inner hole of the guide sleeve 8 at one end of the bending die 1 is used to install the tube blank 6 to be bent and is in sliding fit with the tube blank 6 to be bent. The outer port of the guide sleeve is the feed end of the punch. The feed end of the guide sleeve is provided with an inner punch 4 and an outer punch 5 that slide relative to each other. The inner hole of the guide sleeve 8 at the other end of the bending die 1 is the output end of the bent tube 9.
[0031] A heating rod is installed at the heating rod inlet 2 on the outside of the bending section of the bending die 1 to heat the bending die 1. A cooling groove 3 is provided on the inside of the bending section of the bending die 1. Cooling liquid is introduced through the cooling groove 3 to cool the bending die 1, changing the temperature of the bending die and creating a temperature difference between the inner and outer walls of the cavity of the bending die 1. Before the experiment, the operator can apply different types of lubricant to the inner side 6-1 and the outer side 6-2 of the tube blank 6 to be bent. When the tube blank 6 is bent in the cavity of the bending die 1, the friction coefficient between the outer and inner sides of the bending section of the tube blank 6 and the bending die 1 can be changed, reducing the friction between the inner side 6-1 of the tube blank and the bending die 1. The inner cavity of the tube blank 6 to be bent is filled with filler 7 and placed in the guide sleeve 8. The filler 7 plays a supporting role during the bending process, and the guide sleeve 8 plays a guiding role. A plug 6-3 is welded to the front end of the tube blank 6 to seal the filler 7.
[0032] During the bending deformation process, the inner punch 4 and the outer punch 5 move, pushing the filler 7 and the tube blank 6 to be bent together into the bending cavity of the bending die 1. During bending, the thrust on the inner punch 4 is less than the thrust on the outer punch 5, causing the inner and outer sides of the tube blank 6 to be subjected to different thrusts during bending. During the bending process, the temperature on the outer side of the bending section of the bending die 1 is transferred to the inner wall of the cavity through the bending die 1, forming a temperature difference between the inner and outer sides of the tube blank 6. This temperature difference is adjusted by the temperature of the heating rod and the flow rate of the cooling liquid in the cooling tank. The tube blank 6 is bent and deformed along the bending die 1 under the combined constraint of the bending die 1 and the filler 7. During the bending process, it is simultaneously subjected to active non-uniform temperature difference, differential thrust, and differential friction loading constraints. After forming, as shown... Figure 2 As shown, the bend 9 is formed. Due to the application of differential temperature, differential thrust, and differential friction, the risk of wrinkling on the inner side 9-1 of the bend is low, and the excessive thinning defect on the outer side 9-2 of the bend is greatly suppressed.
[0033] Example 2:
[0034] In this embodiment, the main forming steps and operations are the same as in Embodiment 1. The difference is that in this embodiment, the inner punch 4 and the outer punch 5 have the same thrust, and the blank to be bent 6 is subjected to a combination of two boundary conditions: differential temperature and differential friction during the forming process.
[0035] Example 3:
[0036] In this embodiment, the main forming steps and operations are the same as in Embodiment 1. The difference is that in this embodiment, the bending die is not heated, nor is the bending die cooled by passing coolant through the cooling tank 3. The blank 6 to be bent is subjected to a combination of two boundary conditions: differential thrust and differential friction.
[0037] Example 4:
[0038] In this embodiment, the main forming steps and operations are the same as in Embodiment 1. The difference is that the same type of lubricant is applied to the inner side 6-1 and the outer side 6-2 of the tube blank 6 to be bent in this embodiment. Only a combination of two boundary conditions, differential temperature and differential thrust, are applied to the tube blank 6 to be bent during the forming process.
[0039] The results show that the active non-uniform loading device of this invention can, in principle, change the material flow of the pipe during the bending process through the composite loading boundary, thus affecting the stress and strain state of the bent pipe. By combining the positive effects of each difference condition on the wrinkling and wall thickness reduction suppression of the bent pipe, it can achieve lightweight and high-reliability integral forming of thin-walled, small-bending-radius bent pipes.
[0040] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. An active non-uniform loading tube bending forming device, characterized in that, The device includes a bending die with a heating rod inlet and a cooling groove, an inner punch and an outer punch whose movements can be controlled separately, and a tube blank to be bent with a filler in the inner cavity and the same or different types of lubricant applied to both sides of the bending section.
2. The active non-uniform loading pipe bending forming device according to claim 1, characterized in that, A heating rod insertion port is provided on one side of the bending mold, and a cooling groove is provided on the other side of the bending mold.
3. The active non-uniform loading pipe bending forming device according to claim 2, characterized in that, The heating rod inlet is located on the outside of the bending section of the bending die. There are two or more sets of heating rod inlets, and heating rods are installed inside the heating rod inlets. A cooling tank is provided on the inside of the bending section of the bending die, and the cooling tank is filled with coolant.
4. The active non-uniform loading pipe bending forming device according to claim 1, characterized in that, Guide sleeves are installed at both ends of the bending die by bolts, and the inner hole of each guide sleeve is connected to one port of the bending die cavity.
5. The active non-uniform loading tube bending forming device according to claim 4, characterized in that, The inner hole of the guide sleeve located at one end of the bending die is used to install the tube blank to be bent and is in sliding fit with the tube blank. The outer port of the guide sleeve is the feed end of the punch. The feed end of the guide sleeve is provided with an inner punch and an outer punch that slide relative to each other.
6. The active non-uniform loading pipe bending forming device according to claim 4, characterized in that, The inner hole of the guide sleeve located at the other end of the bending die is the output end of the bent pipe.
7. The active non-uniform loading tube bending forming device according to claim 1, characterized in that, The two sides of the bending section of the tube blank to be bent are the inner side and the outer side of the tube blank, respectively. The same type or different types of lubricant are applied to the inner side and the outer side of the tube blank.
8. The active non-uniform loading tube bending forming device according to claim 1, characterized in that, The inner cavity of the tube blank to be bent is filled with filler and placed in the guide sleeve. A plug is welded to the front end of the tube blank to be bent.