Tube manufacturing process of different-thickness tube

Abstract

The invention relates to a pipe manufacturing process for a pipe with different thicknesses, which is characterized by comprising the following steps of: 1, setting the wall thickness of a target pipe with different thicknesses, selecting a blank with the wall thickness equal to the minimum wall thickness of the target pipe with different thicknesses as a main body pipe blank, and selecting a blank with the wall thickness equal to the difference between the maximum wall thickness and the minimum wall thickness of the target pipe with different thicknesses as a thickened section blank; step 2; the thickened section blank is bonded to the preset thickened position of the main body pipe blank through structural adhesive; thirdly, the main body pipe blank and the thickened section blank which are bonded are welded and bent through a welding and bending mechanism to form a reel pipe; and fourthly, an inner supporting mechanism is placed in the reel pipe, and then the butt joint of the reel pipe is welded through high-frequency induction welding. The pipe manufacturing process is low in cost and high in efficiency, existing equal-thickness plates are adopted as raw materials, and differential-thickness pipes and double-layer pipes can be produced by transforming an existing pipe coil production line; the plates are connected in a welding mode, pipe expanding extrusion friction cannot be generated on the plates, and the problem of local fracture is not prone to occurring.

Description

Technical Field

[0001] The present application relates to the technical field of differential thickness tube manufacturing, and in particular to a tube manufacturing process for differential thickness tubes. Background Art

[0002] Differential thickness tube, also known as variable wall tube or reducer tube, is a tube with uneven wall thickness. It is designed with different wall thicknesses to withstand different pressures and adapt to different environmental conditions. It can make full use of the strength and stiffness of the material, and can better achieve lightweight structure without reducing structural strength. It is of great value to aerospace.

[0003] At present, differential thickness tube blanks are often manufactured using differential thickness plates (TRB). The process includes variable thickness rolling - annealing heat treatment - continuous tube coiling - welding into tubes - weld seam treatment and other steps. The whole process is costly and difficult to achieve large-scale application. Alternatively, seamless tubes are used as blanks. Under the limitation of the outer mold, the tube blanks are mechanically expanded by conical plugs. In this process, the tube is prone to local fracture due to friction. Summary of the invention

[0004] Based on this, it is necessary to provide a pipe manufacturing process for differential thickness pipes to overcome the defects of differential thickness pipes in the prior art, such as high manufacturing cost, complicated process and easy breakage.

[0005] A process for manufacturing a differential thickness tube, characterized in that it comprises the following steps:

[0006] Step 1: Set the target differential thickness tube wall thickness, select the blank with the wall thickness equal to the minimum wall thickness of the target differential thickness tube as the main tube blank, and select the blank with the wall thickness equal to the maximum wall thickness of the target differential thickness tube minus the minimum wall thickness as the thickening section blank;

[0007] Step 2: Bond the thickened section blank to the preset thickened portion of the main tube blank by means of structural adhesive;

[0008] Step 3: welding and bending the bonded main tube blank and the thickened section blank through a welding and bending mechanism to form a coiled tube;

[0009] Step 4: Place the inner support mechanism inside the coiled tube, and then use high-frequency induction welding to weld the butt joints of the coiled tube.

[0010] As a preferred embodiment of the pipe manufacturing process of the differential thickness pipe in the present invention, in the step 2, the bonding area between the main pipe blank and the thickened section blank should be kept clean before bonding.

[0011] As a preferred embodiment of the pipe making process of the differential thickness pipe in the present invention, in the step 2, the center lines of the thickened section blank and the main pipe blank should be aligned when they are bonded.

[0012] As a preferred embodiment of the pipe making process for differential thickness pipes in the present invention, in step three, the welding and bending mechanism comprises a pressing roller, a welding roller and a forming roller which are arranged in sequence.

[0013] As a preferred embodiment of the pipe manufacturing process for the differential thickness pipe in the present invention, the main pipe blank and the thickened section blank are made of conductive metal materials.

[0014] As a preferred embodiment of the pipe making process of the differential thickness pipe in the present invention, the width side of the thickened section blank is a beveled slope.

[0015] As a preferred embodiment of the pipe making process for differential thickness pipes in the present invention, the inner support mechanism is arranged along the butt joint of the rolled pipe, with one end thereof abutting against both sides of the butt joint and the other end thereof abutting against the opposite side of the butt joint.

[0016] As a preferred embodiment of the pipe manufacturing process for the differential thickness pipe in the present invention, the width of the inner support mechanism matches the inner diameter of the target differential thickness pipe.

[0017] As a preferred embodiment of the pipe making process for differential thickness pipes in the present invention, the inner support mechanism includes a clamping plate, and abutment blocks are provided at both ends of the clamping plate. The ends of the abutment blocks are arc-shaped, one end of which is clamped in the clamping plate and the other end of which extends out of the clamping plate.

[0018] As a preferred embodiment of the pipe manufacturing process for differential thickness pipes in the present invention, grooves are provided at positions of the abutment blocks corresponding to the butt joints.

[0019] Beneficial effects of the present invention:

[0020] 1. Compared with the differential thickness plate (TRB) manufacturing, the present invention has low cost and high efficiency in the pipe manufacturing process. It uses the existing equal thickness plate as the raw material and can produce differential thickness pipes and double-layer pipes by transforming the existing pipe coil production line;

[0021] 2. Compared with the seamless pipe expansion manufacturing, the present invention adopts welding to connect the plates, which will not cause the plate to be squeezed and frictioned by the expansion, and is not prone to local fracture problems;

[0022] 3. The pipe size of the present invention is flexible, and the length and thickness of the differential thickness section can be adjusted at any time to meet the production of differential thickness pipes of different specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1This is a schematic diagram of the process of differential thickness pipe making in Example 1 of the present application;

[0025] Figure 2 for Figure 1 Schematic diagram of the cross section at AA in the middle;

[0026] Figure 3 for Figure 1 Schematic diagram of the cross section at BB;

[0027] Figure 4 for Figure 1 Schematic diagram of the cross section at CC;

[0028] Figure 5 for Figure 1 Schematic diagram of the cross section at DD in the middle;

[0029] Figure 6 This is a schematic diagram of the connection between the support device and the coiled pipe in Example 1 of the present application;

[0030] Figure 7 Schematic diagram of the process of double-layer pipe making in Example 2 of the present application;

[0031] Description of reference numerals:

[0032] 1. Main tube blank;

[0033] 2. Thickened section blank

[0034] 3. Structural adhesive;

[0035] 4. Pressing roller;

[0036] 5. Welding roller;

[0037] 6. Forming roller;

[0038] 7. Inner layer blank;

[0039] 8. Internal support mechanism. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0041] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0042] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0043] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0045] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0046] Example 1

[0047] This embodiment provides a pipe manufacturing process for a differential thickness pipe, comprising the following steps:

[0048] A1: Set the target differential tube wall thickness, set the minimum wall thickness to T1, the maximum wall thickness to T1+T2, select the blank with a wall thickness of T1 as the main tube blank 1, select the blank with a wall thickness of T2 as the thickening section blank 2, and the thickening section blank 2 is a discontinuous sheet.

[0049] A2: The width side of the thickened section blank 2 is beveled into a slope surface as a transition section from the wall thickness T1 to T1+T2.

[0050] A3: After beveling, clean the plate surfaces of the main tube blank 1 and the thickened section blank 2 to ensure that there is no adverse effect on the bonding of the main tube blank 1 and the thickened section blank 2.

[0051] A4: Apply structural adhesive 3 at the connection between the main tube blank 1 and the thickened section blank 2, such as Figure 2 As shown, the thickened section blank 2 is placed at the glue coating position, and the center lines of the main tube blank 1 and the thickened section blank 2 are aligned, and then sent to the welding and bending mechanism for welding and bending to form a rolled tube.

[0052] A5: An internal support mechanism 8 is placed inside the coiled tube. The internal support mechanism 8 is arranged along the butt joint of the coiled tube and its ends are in contact with the tube bodies on both sides of the butt joint and the opposite ends of the butt joint. The butt joint of the coiled tube is then welded using high-frequency induction welding.

[0053] In this embodiment, if Figure 1 As shown, a glue coating mechanism is provided between the main tube blank 1 and the welding bending mechanism. The welding bending mechanism comprises a pressing roller 4, a welding roller 5 and a forming roller 6 which are arranged in sequence.

[0054] like Figure 3 As shown, the pressing roller 4 is used to extrude the main tube blank 1 and the thickened section blank 2 so that there is no gap between the two and they are firmly bonded.

[0055] like Figure 4 As shown, the welding roller 5 is energized to weld the main tube blank 1 and the thickened section blank 2 into a whole.

[0056] like Figure 5 As shown, a plurality of forming rollers 6 bend and curl the welded sheet material, and the two long sides abut against each other to form a rolled tube.

[0057] In this embodiment, in order to realize the electric welding of the main tube blank 1 and the thickened section blank 2, the main tube blank 1 and the thickened section blank 2 are made of conductive metal materials such as steel, stainless steel, aluminum alloy, copper alloy, etc.

[0058] like Figure 6 As shown, the inner support mechanism 8 is arranged along the butt joint of the rolling tube, one end of which abuts against both sides of the butt joint, and the other end of which abuts against the opposite side of the butt joint.

[0059] In this embodiment, the width of the inner support mechanism 8 matches the inner diameter of the target differential thickness tube, and the width at the abutment with the thickened section is smaller than the width at the abutment with the main tube blank 1 .

[0060] In this embodiment, the internal support mechanism 8 includes a splint, which extends along the axial direction of the rolling tube, with gaps provided between the splints, and abutment blocks provided at both ends of the gaps of the splints. The ends of the abutment blocks are arc-shaped, and their curvature matches the internal curvature of the target differential thickness tube. One end of the abutment block is clamped in the splint, and the other end extends out of the splint to abut against the inner wall of the rolling tube.

[0061] In this embodiment, a groove is provided at a position of the abutting block corresponding to the butt joint, and the groove does not directly contact the butt joint to avoid affecting the welding of the butt joint.

[0062] Example 2

[0063] This embodiment provides a double-layer tube manufacturing process. Figure 7 As shown, the following steps are included:

[0064] B1: Set the target differential tube wall thickness, set the wall thickness to T1+T2, select the blank with wall thickness T1 as the main tube blank 1, select the blank with wall thickness T2 as the inner layer blank 7, and the inner layer blank 7 is a continuous sheet.

[0065] B2: Clean the plate surfaces of the main tube blank 1 and the inner layer blank 7 to ensure that there is no adverse effect on the bonding of the main tube blank 1 and the inner layer blank 7.

[0066] B3: Apply structural glue 3 at the connection between the main tube blank 1 and the inner layer blank 7, place the inner layer blank 7 at the glue-coated position, and ensure that the center lines of the main tube blank 1 and the inner layer blank 7 are aligned, and then send them into the welding and bending mechanism for welding and bending to form a rolled tube.

[0067] B4: An internal support mechanism 8 is placed inside the coiled pipe. The internal support mechanism 8 is arranged along the butt joint of the coiled pipe and its ends are in contact with the pipe bodies on both sides of the butt joint and the opposite ends of the butt joint. The butt joint of the coiled pipe is then welded using high-frequency induction welding.

[0068] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0069] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A process for making a differential thickness tube, characterized in that: The steps include: Step 1: Set the target differential thickness tube wall thickness, select the blank with the wall thickness equal to the minimum wall thickness of the target differential thickness tube as the main tube blank, and select the blank with the wall thickness equal to the maximum wall thickness of the target differential thickness tube minus the minimum wall thickness as the thickening section blank; Step 2: Bond the thickened section blank to the preset thickened portion of the main tube blank by means of structural adhesive; Step 3: welding and bending the bonded main tube blank and the thickened section blank through a welding and bending mechanism to form a coiled tube; Step 4: Place the inner support mechanism inside the coiled tube, and then use high-frequency induction welding to weld the butt joints of the coiled tube.

2. The process for making a differential thickness tube according to claim 1, characterized in that: In the step 2, the bonding area between the main tube blank and the thickened section blank should be kept clean before bonding.

3. The process for making a differential thickness tube according to claim 2, characterized in that: In the step 2, the center lines of the thickened section blank and the main tube blank should be aligned when they are bonded.

4. The process for making a differential thickness tube according to claim 1, characterized in that: In the step three, the welding bending mechanism includes a pressing roller, a welding roller and a forming roller which are arranged in sequence.

5. The process for making a differential thickness tube according to claim 1, characterized in that: The main tube blank and the thickened section blank are made of conductive metal materials.

6. The process for making a differential thickness tube according to claim 1, characterized in that: The width side of the thickened section blank is a beveled slope.

7. The process for making a differential thickness tube according to claim 1, characterized in that: The inner support mechanism is arranged along the butt joint of the coiled tube, one end of the inner support mechanism abuts against two sides of the butt joint, and the other end of the inner support mechanism abuts against the opposite side of the butt joint.

8. The process for making a differential thickness tube according to claim 7, characterized in that: The width of the inner support mechanism matches the inner diameter of the target differential thickness tube.

9. The process for making a differential thickness tube according to claim 8, characterized in that: The inner support mechanism comprises a clamping plate, and abutment blocks are arranged at both ends of the clamping plate. The end of the abutment block is arc-shaped, one end of which is clamped in the clamping plate, and the other end of which extends out of the clamping plate.

10. The process for making a differential thickness tube according to claim 9, characterized in that: A groove is provided at a position of the abutting block corresponding to the butt joint.

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