Pipe with wave type pre-deformation structure and production method thereof

Abstract

The invention relates to a pipe with a wave-type pre-deformation structure and a production method of the pipe. The pipe comprises an outer pipe and an inner pipe, an inner tube; the reinforcing structures are connected with the outer pipe and the inner pipe, each reinforcing structure comprises a first reinforcing rib and a second reinforcing rib, the second reinforcing ribs and the first reinforcing ribs are arranged in a mirror image mode, and the section, parallel to the direction of the outer pipe, of each first reinforcing rib is in an arc shape; the inner pipe between the first reinforcing ribs and the second reinforcing ribs, the inner pipe between every two adjacent first reinforcing ribs and the inner pipe between every two adjacent second reinforcing ribs are in an arc shape, and the tops of the arcs are tightly attached to the outer pipe. Compared with the prior art, the pressure bearing degree of the pipe is increased, the thickness of the pipe is reduced, and pipe materials are saved.

Description

Technical Field

[0001] The present invention belongs to the technical field of pipe materials, and particularly relates to a pipe with a wavy pre-deformation structure and a production method thereof. Background Art

[0002] In the modern construction industry, aluminum alloy is a very common material and can be made into various items for use. Among them, aluminum alloy pipes are used the most, which can replace other pipes for use and improve the usage efficiency. The main reason for using aluminum alloy pipes during use is that they have good performance and can improve the usage effect during use.

[0003] The characteristics of aluminum alloy pipes mainly include several points.

[0004] First, it has extremely high strength and can prevent damage when collided with other objects during use. Aluminum alloy pipes have extremely high strength. Compared with ordinary steel pipes, they are not easily damaged, can improve the usage efficiency, and extend the service life.

[0005] Second, during the manufacturing process, it has undergone various chemical material tests and can reduce the occurrence of corrosion by chemical elements during use. It can resist the corrosion of various chemical elements during use and increase the service time during use.

[0006] Third, during use, due to its extremely high strength, it will not deform during use. It can be suitable for use in any place and improve the adaptability to the use environment.

[0007] However, for conventional thick-walled solid pipes, when there is internal hydraulic pressure, the wall stress is distributed in a gradient, and the material's performance potential cannot be fully utilized. Moreover, to increase the pressure-bearing capacity, the pipe thickness is often increased.

[0008] CN107289204A discloses an array-type pre-deformed double-layer mechanical pipe and its outer pipe and lining pipe. The outer wall of the lining pipe is closely attached to the inner wall of the outer pipe, and there are multiple non-fitting plastic deformations between the outer wall of the lining pipe and the inner wall of the outer pipe. The plastic deformations are arranged on the surface of the lining pipe and are recessed downward towards the center of the lining pipe. The positions of the plastic deformations are the critical defect positions of the lining pipe, and the critical defects are artificially created defects arranged periodically. However, this application only enhances the thickness of the outer pipe, and the deformed part of the lining pipe is far from the outer pipe and is not fully attached to the outer pipe. The formed pre-deformation structure only solves the problem that the lining thickness of the double-layer pipe does not need to be increased. Summary of the Invention

[0009] The object of the present invention is to overcome the defects of the above-mentioned existing technologies and provide a pipe with a wavy pre-deformation structure and a production method thereof.

[0010] The object of the present invention can be achieved by the following technical solutions:

[0011] The first aspect of the present invention provides a pipe with a wavy pre-deformation structure, including:

[0012] An outer pipe;

[0013] An inner pipe; and

[0014] A number of strengthening structures connecting the outer pipe and the inner pipe, which include a first reinforcing rib and a second reinforcing rib. The first reinforcing rib and the second reinforcing rib are arranged alternately in sequence. The cross-sections of the first reinforcing rib and the second reinforcing rib in the direction perpendicular to the outer pipe are arc-shaped and the bending directions of the second reinforcing rib and the first reinforcing rib are opposite;

[0015] The inner pipe between the first reinforcing rib and the second reinforcing rib is stamped into an arc shape and the top of the arc shape is in close contact with the outer pipe.

[0016] Further, the strengthening structures are evenly arranged between the outer pipe and the inner pipe.

[0017] Further, one end of the first reinforcing rib abuts against the outer pipe and the other end abuts against the inner pipe;

[0018] One end of the second reinforcing rib abuts against the outer pipe and the other end abuts against the inner pipe.

[0019] Further, the material of the strengthening structure is a metal material.

[0020] Further, the materials of both the outer pipe and the inner pipe are metal materials.

[0021] Furthermore, the material of the outer pipe is selected from one or more of 7075T6 aluminum alloy, 7A04 T6 aluminum alloy or other high-strength aluminum alloys.

[0022] Furthermore, the material of the inner pipe is selected from one or more of 7475 aluminum alloy, 7050 aluminum alloy or 7175 aluminum alloy.

[0023] Further, the tensile strength of the outer pipe is greater than that of the inner pipe, the tensile strength of the strengthening structure is greater than that of the inner pipe, and the toughness of the inner pipe is greater than that of the outer pipe.

[0024] Furthermore, the ratio of the thickness of the first reinforcing rib to the inner diameter of the outer tube is 40:1 - 60:1, and the ratio of the thickness of the second reinforcing rib to the inner diameter of the outer tube is 40:1 - 60:1.

[0025] Preferably, the material of the outer tube is 7075T6 aluminum alloy.

[0026] Preferably, the material of the reinforcing structure is 7075T6 aluminum alloy.

[0027] Preferably, the material of the inner tube is 7475 aluminum alloy.

[0028] Preferably, the ratio of the thickness of the first reinforcing rib to the inner diameter of the outer tube is 50:1, and the ratio of the thickness of the second reinforcing rib to the inner diameter of the outer tube is 50:1.

[0029] In the second aspect of the present invention, a production method of a pipe with a wavy pre-deformation structure is provided, including the following steps:

[0030] S1: Prepare a prefabricated rigid tooling that matches the outer tube according to the shape and size of the outer tube;

[0031] S2: Assemble the inner tube, the outer tube, and the reinforcing structure and place the outer tube in the prefabricated rigid tooling, with the outer tube closely attached to the prefabricated rigid tooling;

[0032] S3: Perform a uniform primary hydraulic pressure along the circumferential direction of the inner tube, with the primary hydraulic pressure being 50 - 80 MPa and the primary hydraulic time being 20 - 40 min;

[0033] S4: Then perform a uniform secondary hydraulic pressure along the circumferential direction of the inner tube, with the secondary hydraulic pressure increased by 20% - 40%, the secondary hydraulic time being 25 - 45 min, and continuously increasing the number of hydraulic pressure times consistent with the secondary hydraulic pressure until the inner tube between the first reinforcing rib and the second reinforcing rib is in an arc shape and the top of the arc shape is closely attached to the outer tube, and the interval between two adjacent secondary hydraulic pressures is 0.5 - 3 min.

[0034] Preferably, the primary hydraulic time is 30 min.

[0035] Preferably, the primary hydraulic pressure is 70 MPa.

[0036] Preferably, the secondary hydraulic pressure is increased by 40%.

[0037] Preferably, the secondary hydraulic time is 30 min.

[0038] Preferably, the interval between two adjacent secondary hydraulic pressure times is 1 min.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] (1) The inner tube of this pipe is attached to the outer tube through a strengthening structure, thereby improving the overall hydraulic stamping resistance of the pipe, having good airtightness, and expanding the application range of the pipe.

[0041] (2) Without increasing the thickness, this pipe can enhance the overall hydraulic stamping resistance of the pipe, reduce the material usage of the pipe, and save costs. Description of the Drawings

[0042] Figure 1 It is a schematic cross-sectional view of this pipe in Embodiment 1.

[0043] Figure 2 It is a schematic cross-sectional view of this pipe without pre-deformation in Comparative Example 1.

[0044] Figure 3 It is a schematic process flow diagram of the production process of this pipe in Embodiment 2.

[0045] 1 - outer tube, 2 - inner tube, 3 - strengthening structure, 301 - first reinforcing rib, 302 - second reinforcing rib. Detailed Embodiments

[0046] The present invention will be described in detail below with reference to the drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and detailed implementation manners and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0047] In this technical solution, features such as component models, material names, connection structures, and control methods that are not clearly described are regarded as common technical features disclosed in the prior art.

[0048] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "upper", "lower", "vertical", "horizontal", "top", "bottom", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0049] In the description of the present invention, the meaning of "a plurality" is two or more, unless otherwise specifically defined. In addition, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a bolt connection or a welded connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] In order to increase the pressure-bearing capacity of the pipe, reduce the pipe thickness, and save pipe materials, the present invention provides a pipe with a wavy pre-deformation structure, and its structure can be seen in Figure 1 as shown, including:

[0051] an outer pipe 1;

[0052] an inner pipe 2; and

[0053] several strengthening structures 3 connecting the outer pipe 1 and the inner pipe 2, which include a first reinforcing rib 301 and a second reinforcing rib 302 arranged mirror-symmetrically with respect to the first reinforcing rib 301, and the cross-section of the first reinforcing rib 301 in the direction parallel to the outer pipe 1 is arc-shaped;

[0054] The inner pipe 2 between the first reinforcing rib 301 and the second reinforcing rib 302, the inner pipe 2 between two adjacent first reinforcing ribs 301, and the inner pipe 2 between two adjacent second reinforcing ribs 302 are arc-shaped and the top of the arc shape is in close contact with the outer pipe 1.

[0055] In some specific embodiments, please refer to Figure 1 as shown, the strengthening structures 3 are evenly arranged between the outer pipe 1 and the inner pipe 2.

[0056] In some specific embodiments, please refer to Figure 1 as shown, one end of the first reinforcing rib 301 abuts against the outer pipe 1 and the other end abuts against the inner pipe 2;

[0057] One end of the second reinforcing rib 302 abuts against the outer pipe 1 and the other end abuts against the inner pipe 2.

[0058] In some specific embodiments, please refer to Figure 1 as shown, the material of the strengthening structure 3 is a metal material.

[0059] In some specific embodiments, please refer to Figure 1 as shown, the materials of the outer pipe 1 and the inner pipe 2 are both metal materials.

[0060] In a more specific embodiment, please refer to Figure 1 as shown, the material of the outer pipe 1 is selected from one or more of 7075T6 aluminum alloy, 7A04 T6 aluminum alloy or other high-strength aluminum alloys.

[0061] In a more specific embodiment, please refer to Figure 1 as shown, the material of the inner pipe 2 is selected from one or more of 7475 aluminum alloy, 7050 aluminum alloy or 7175 aluminum alloy.

[0062] In some specific embodiments, please refer toFigure 1 As shown, the strength of the outer tube 1 is greater than that of the inner tube 2, the strength of the reinforcement structure 3 is greater than that of the inner tube 2, and the toughness of the inner tube 2 is greater than that of the outer tube 1.

[0063] In some specific embodiments, please refer to Figure 1 As shown, the ratio of the thickness of the first reinforcing rib 301 to the inner diameter of the outer tube 1 is 40:1 - 60:1, and the ratio of the thickness of the second reinforcing rib 302 to the inner diameter of the outer tube 1 is 40:1 - 60:1.

[0064] The present invention also provides a production method for a pipe with a wavy pre - deformation structure. The step - by - step process is shown in Figure 3 As shown, it includes the following steps:

[0065] S1: Prepare a pre - fabricated rigid tooling that matches the outer tube 1 according to the shape and size of the outer tube 1;

[0066] S2: Assemble the inner tube 2, the outer tube 1, and the reinforcement structure 3 and place the outer tube 1 in the pre - fabricated rigid tooling, with the outer tube 1 in close contact with the pre - fabricated rigid tooling;

[0067] S3: Perform a uniform first - stage hydraulic pressure along the circumferential direction of the inner tube 2. The pressure of the first - stage hydraulic pressure is 50 - 80 MPa, and the time of the first - stage hydraulic pressure is 20 - 40 min;

[0068] S4: Then perform a uniform second - stage hydraulic pressure along the circumferential direction of the inner tube 2. The pressure of the second - stage hydraulic pressure increases by 20% - 40%. The time of the second - stage hydraulic pressure is 25 - 45 min. Continuously increase the number of hydraulic pressure times consistent with the pressure of the second - stage hydraulic pressure until the inner tube 2 between the first reinforcing rib 301 and the second reinforcing rib 302 is in an arc shape and the top of the arc shape is in close contact with the outer tube 1, and the interval between two adjacent second - stage hydraulic pressures is 0.5 - 3 min.

[0069] The above - mentioned embodiments can be implemented separately, or combined in any pairwise or more combinations.

[0070] The above - mentioned embodiments will be described in more detail below with specific examples.

[0071] Example 1

[0072] Refer to Figure 1 As shown, in order to increase the pressure - bearing capacity of the pipe, reduce the pipe thickness, and save pipe materials, this example provides a pipe with a wavy pre - deformation structure.

[0073] Figure 2 This is a cross - sectional schematic diagram of the pipe. This pipe includes an outer tube 1 and an inner tube 2 connected to the outer tube through a reinforcement structure 3.

[0074] Among them, one end of the first reinforcing rib 301 of the reinforcing structure 3 abuts against the outer tube 1, and the other end abuts against the inner tube 2. One end of the second reinforcing rib 302 of the reinforcing structure 3 abuts against the outer tube 1, and the other end abuts against the inner tube 2. Moreover, the material of the reinforcing structure 3 is 7075T6 aluminum alloy. And the cross-section of the first reinforcing rib 301 in the direction parallel to the outer tube 1 is arc-shaped. The second reinforcing rib 302 is arranged in a mirror image of the first reinforcing rib 301 and is spaced apart by a certain distance. And the strength of the reinforcing structure 3 is greater than that of the inner tube 2 to meet the requirement that no deformation occurs during the pre-deformation of the inner tube 2.

[0075] The inner tube 2 is attached to the outer tube 1 by stamping. The attachment parts are the inner tube 2 between two adjacent first reinforcing ribs 301, the inner tube 2 between two adjacent second reinforcing ribs 302, and the inner tube 2 between the first reinforcing rib 301 and the second reinforcing rib 302. The inner tube at this part is arc-shaped and the top of its arc shape is attached to the outer tube 1.

[0076] Among them, the material of the outer tube 1 is 7075T6 aluminum alloy, and the material of the inner tube is 7475 aluminum alloy.

[0077] In this embodiment, the inner diameter of the outer tube 1 is 300 mm, the thickness is 2 mm, the thickness of the first reinforcing rib 301 is 6 mm, and the thickness of the second reinforcing rib 302 is 6 mm.

[0078] Comparative Example 1

[0079] This comparative example provides a pipe without a wavy pre-deformation structure. Refer to Figure 2 , and the inner diameter and thickness of the outer tube, the first reinforcing rib, and the second reinforcing rib in this comparative example are the same as those of the outer tube, the first reinforcing rib, and the second reinforcing rib in Embodiment 1.

[0080] Comparative Example 2

[0081] This comparative example provides a structure with only one layer of pipe, and the pipe has the same inner diameter and thickness as the outer tube 1 in Embodiment 1, and the material is 7075T6 aluminum alloy.

[0082] Comparative Example 3

[0083] This comparative example provides a structure with only one layer of pipe, and the pipe has the same inner diameter and thickness as the outer tube 1 in Embodiment 1, and the material is 7475 aluminum alloy.

[0084] Refer to Figure 1 , for pipes without vertical pre-deformation and refer to Figure 2, a hydrostatic test is carried out on the vertically pre-deformed pipe together, and the hydrostatic test is as follows: First, fill the pipes in Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3 with clean industrial water, and the test water temperature is 15 °C. Then, use a water pump to pressurize the pipe to 87.5 MPa. Before pressurization, air must be completely removed, otherwise it will cause pressure instability. Air can be exhausted through the valve installed at the highest point of the container. When pressurization starts, gradually open the exhaust valve to exhaust air until water is seen flowing out, and pressurize for 30 minutes.

[0085] Test results:

[0086] The final result of Example 1 is that no leakage is seen in 30 minutes;

[0087] The final result of Comparative Example 1 is leakage in 15 minutes;

[0088] The final result of Comparative Example 2 is leakage in 10 minutes;

[0089] The final result of Comparative Example 3 is leakage in 8 minutes.

[0090] Analysis:

[0091] It is found from the test that the pipe in Example 1 has good airtightness and strong anti-hydrostatic pressure ability.

[0092] Example 2

[0093] The present invention provides a production method of a pipe with a wavy pre-deformation structure in Example 1, and the step process is shown in Figure 3 as follows, including the following steps:

[0094] S1: Prepare a prefabricated rigid tooling that matches the outer pipe 1 according to the shape and size of the outer pipe 1;

[0095] S2: Assemble the inner pipe 2, the outer pipe 1, and the strengthening structure 3 and place the outer pipe 1 in the prefabricated rigid tooling, where the outer pipe 1 is in close contact with the prefabricated rigid tooling;

[0096] S3: Perform a uniform primary hydraulic pressure along the circumferential direction of the inner pipe 2, the pressure of the primary hydraulic pressure is 70 MPa, and the time of the primary stamping is 30 minutes;

[0097] S4: Then perform a uniform secondary hydraulic pressure along the circumferential direction of the inner pipe 2, the pressure of the secondary hydraulic pressure increases by 40%, the time of the secondary hydraulic pressure is 30 minutes, and continuously increase the number of hydraulic pressure times consistent with the pressure of the secondary hydraulic pressure until the inner pipe 2 between the first reinforcing rib 301 and the second reinforcing rib 302 is in an arc shape and the top of the arc shape is in close contact with the outer pipe 1, and the interval between adjacent two secondary hydraulic pressures is 1 minute.

[0098] The above description of the embodiments is to enable those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and all improvements and modifications made by those skilled in the art without departing from the scope of the present invention according to the disclosure of the present invention should be within the protection scope of the present invention.

Claims

1. A pipe with a wavy pre-deformation structure, characterized in that, Comprising: An outer tube (1); An inner tube (2); And A plurality of strengthening structures (3) connecting the outer tube (1) and the inner tube (2), which include a first reinforcing rib (301) and a second reinforcing rib (302), the first reinforcing rib (301) and the second reinforcing rib (302) are arranged alternately in sequence, the cross-section of the first reinforcing rib (301) and the second reinforcing rib (302) along the direction perpendicular to the outer tube (1) is arc-shaped and the bending direction of the second reinforcing rib (302) is opposite to that of the first reinforcing rib (301); The inner tube (2) between the first reinforcing rib (301) and the second reinforcing rib (302) is pressed into an arc shape and the top of the arc shape is in close contact with the outer tube (1).

2. The pipe with a wavy pre-deformation structure according to claim 1, characterized in that, The strengthening structures (3) are evenly arranged between the outer tube (1) and the inner tube (2).

3. The pipe with a wavy pre-deformation structure according to claim 1, characterized in that, One end of the first reinforcing rib (301) abuts against the outer tube (1), and the other end abuts against the inner tube (2); One end of the second reinforcing rib (302) abuts against the outer tube (1), and the other end abuts against the inner tube (2).

4. The pipe with a wavy pre-deformation structure according to claim 1, characterized in that, The material of the strengthening structure (3) is a metal material.

5. The pipe with a wavy pre-deformation structure according to claim 1, characterized in that, The materials of the outer tube (1) and the inner tube (2) are both metal materials.

6. The pipe with a wavy pre-deformation structure according to claim 5, characterized in that, The material of the outer tube (1) is selected from one or more of 7075T6 aluminum alloy, 7A04 T6 aluminum alloy or other high-strength aluminum alloys.

7. The pipe with a wavy pre-deformation structure according to claim 5, characterized in that, The material of the inner tube (2) is selected from one or more of 7475 aluminum alloy, 7050 aluminum alloy or 7175 aluminum alloy.

8. The pipe with a wavy pre-deformation structure according to claim 1, characterized in that, The tensile strength of the outer tube (1) is greater than that of the inner tube (2), the tensile strength of the strengthening structure (3) is greater than that of the inner tube (2), and the toughness of the inner tube (2) is greater than that of the outer tube (1).

9. The pipe with a wavy pre-deformation structure according to claim 1, characterized in that, The ratio of the thickness of the first reinforcing rib (301) to the inner diameter of the outer tube (1) is 40:1 - 60:1, and the ratio of the thickness of the second reinforcing rib (302) to the inner diameter of the outer tube (1) is 40:1 - 60:

1.

10. A production method of the pipe with a wavy pre-deformation structure according to any one of claims 1-9, characterized in that, Including the following steps: S1: According to the shape and size of the outer tube (1), prepare a prefabricated rigid tooling that matches the outer tube (1); S2: Assemble the inner tube (2), the outer tube (1), and the strengthening structure (3) and place the outer tube (1) in the prefabricated rigid tooling, and the outer tube (1) is in close contact with the prefabricated rigid tooling; S3: Perform a uniform primary hydraulic pressure along the circumferential direction of the inner tube (2), the pressure of the primary hydraulic pressure is 50 - 80 MPa, and the time of the primary hydraulic pressure is 20 - 40 min; S4: Then perform a uniform secondary hydraulic pressure along the circumferential direction of the inner tube (2), the pressure of the secondary hydraulic pressure increases by 20% - 40%, the time of the secondary hydraulic pressure is 25 - 45 min, and continuously increase the number of hydraulic pressure times consistent with the pressure of the secondary hydraulic pressure until the inner tube (2) between the first reinforcing rib (301) and the second reinforcing rib (302) is in an arc shape and the top of the arc shape is in close contact with the outer tube (1), and the interval between two adjacent secondary hydraulic pressures is 0.5 - 3 min.

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