Point-type crimping structure, point-type crimping tool, and point-type crimping method for metal pipe

Abstract

The present invention relates to the field of connection technology, and discloses a point-type crimping structure, a point-type crimping tool, and a point-type crimping method for a metal tube. The point-type crimping structure of the metal tube includes a plurality of crimping points distributed on the metal tube, each crimping point is on a different circumference, and there is only one crimping point on each circumference. The point-type crimping tool includes a tool body and a crimping screw. The tool body is a U-shaped structure, and a semicircular mold groove for placing the metal tube to be crimped is provided on the left side. The crimping screw is rotatably mounted on the right side of the tool body. The axis of the crimping screw and the axis of the semicircular mold groove are on the same plane and perpendicular to each other. One end of the crimping screw is a crimping head, and the other end is a handle. Compared with conventional radial crimping, the point-type crimping structure of the present invention greatly reduces the pressure drop and reduces the flow resistance while ensuring the resistance to pull-off.

Description

Technical Field

[0001] The present invention relates to the field of connection technology, and in particular to a point-type crimping structure, a point-type crimping tool, and a point-type crimping method for a metal pipe. Background Art

[0002] Common methods for connecting tubular metal parts are radial crimping and axial crimping. To ensure sufficient pull-out resistance between the metal tubes after connection, both crimping methods rely on molds to shrink the inner and outer metal tubes toward the axis, making the diameter of the shrinking position smaller than the size of the metal inner tube in the non-crushed position. As a result, although the pull-out resistance between the metal tubes is achieved, the flow resistance of the medium in the tube is also increased, which means that the pressure drop is increased.

[0003] Take radial buckling as an example to illustrate. Figure 1 As shown, a is the outer metal tube, b is the inner metal tube, and c is the shape of radial pressing. C-1 on the AA cross-sectional view on the left is actually the shape of the inner metal tube b after deformation by radial pressing. Note: The inner diameter of the deformed shape of tube b in c-1 is significantly smaller than the non-pressed inner diameter of the inner metal tube b. The deformed shape of tube b is precisely the source of the increase in medium flow resistance. The multiple mold flaps of radial pressing are evenly distributed 360 degrees along the circumference. When pressure is applied, they will simultaneously shrink toward the center of the circle until the required diameter size is reached and then exit. The shape of the position where each mold flap contacts the metal tube being pressed is called a pressing point. From Figure 2 ( Figure 1 The AA section of the steel sheet shows that these multiple crimping points form a roughly circular shape. The shape of each crimping point and the crimping depth determine the pull-out resistance and pressure drop. Summary of the Invention

[0004] The main purpose of the present invention is to overcome the deficiencies of the prior art and to provide a point-type crimping structure, a point-type crimping tool, and a point-type crimping method for a metal pipe.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A point-type crimping structure for a metal pipe includes a plurality of crimping points distributed on the metal pipe, each crimping point is on a different circumference, each circumference has only one crimping point, and the crimping points include at least two, and the two crimping points are distributed on a symmetrical element line.

[0007] Preferably, viewed along the axial direction, any two pressing points are not on the same element line.

[0008] Taking the number of buckling points as four as an example, the angle between adjacent buckling points is 90°.

[0009] The present invention also discloses a point-type crimping tool for realizing the above-mentioned point-type crimping structure, including a tool body and a crimping screw. The tool body is a U-shaped structure, and a semicircular mold groove for placing the metal tube to be crimped is provided on the left side. The crimping screw can be rotatably installed on the right side of the tool body. The axis of the crimping screw and the axis of the semicircular mold groove are on the same plane and are perpendicular to each other. One end of the crimping screw is a crimping head and the other end is a handle.

[0010] The present invention also discloses a method for performing point crimping using the point crimping tool, comprising the following steps:

[0011] Step 1: Place the metal tubes to be crimped together in the semicircular mold groove, rotate the handle of the crimping screw so that the crimping head is aligned with the metal tube to crimp the first crimping point;

[0012] Step 2: Rotate the handle in the opposite direction to withdraw the pressing screw;

[0013] Step 3: Push the metal tube forward a certain length along the axis, rotate the metal tube, and then rotate the handle of the crimping screw so that the crimping head is aligned with the metal tube to crimp out the second crimping point;

[0014] Step 4: Repeat steps 2 and 3 until all the crimping actions are completed.

[0015] The present invention has the following beneficial effects: compared with conventional radial buckling, the point-type buckling structure of the present invention greatly reduces the pressure drop and reduces the flow resistance while ensuring the anti-pull-out force. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of radial buckling;

[0017] Figure 2 yes Figure 1 AA section view;

[0018] Figure 3 It is an expanded view of a metal tube with a point-type crimping structure;

[0019] Figure 4 of Figure 3 Front view of the metal tube;

[0020] Figure 5 1. It is a schematic diagram of the structure of a point-type crimping tool;

[0021] Figure 6 This is a front view of the radially crimped eight-petal die;

[0022] Figure 7 yes Figure 6 The expanded diagram of

[0023] Among them, the above-mentioned drawings include the following figure marks: 1. crimping point; 2. tool body; 21. semicircular mold groove; 3. crimping screw; 31. crimping head; 32. handle; 4. metal tube to be crimped. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to the accompanying drawings.

[0025] The point-type crimping structure of the metal tube described in the present invention includes several crimping points, each crimping point is on a different circumference, there is only one crimping point on each circumference, and there are at least two crimping points, which are distributed on a symmetrical element line.

[0026] The point-type buckling structure of the present invention needs to satisfy that all buckling points are distributed on different circumferences, and there is only one buckling point on each circumference. At the same time, when viewed along the axial direction, all buckling points are on different element lines. Taking four buckling points as an example, Figure 3-4 As shown, the four buckling points are all on different element lines. In this example, the angle between adjacent buckling points is 90°.

[0027] There is no limit to the number of crimping points, which can be determined according to actual needs. However, in practical applications, eight crimping points are most commonly used.

[0028] like Figure 5 As shown, the present invention also discloses a point-type crimping tool of the above-mentioned point-type crimping structure, which includes a tool body 2 and a crimping screw 3. The tool body is a U-shaped structure, and a semicircular mold groove 21 for placing the metal tube 4 to be crimped is provided on the left side. The crimping screw is rotatably installed on the right side of the tool body. The axis of the crimping screw and the axis of the semicircular mold groove are on the same plane and perpendicular to each other. One end of the crimping screw 3 is a crimping head 31, and the other end is a handle 32.

[0029] The above-mentioned crimping tool is a simple manual crimping tool, and an electric or hydraulic crimping tool can also be used in actual application.

[0030] The method for performing point crimping using the above-mentioned point crimping tool comprises the following steps:

[0031] Step 1: Place the metal tubes (including inner tube and outer tube) to be crimped into the semicircular mold groove, rotate the handle of the crimping screw so that the crimping head is aligned with the metal tube to crimp the first crimping point;

[0032] Step 2: Rotate the handle in the opposite direction to withdraw the pressing screw;

[0033] Step 3: Push the metal tube forward along the axis of the metal tube for a certain length, rotate the metal tube to a certain angle, and then rotate the handle of the crimping screw so that the crimping head is aligned with the metal tube to crimp out the second crimping point;

[0034] Step 4: Repeat steps 2 and 3 until all the crimping actions are completed.

[0035] In addition to using the above-mentioned point-type crimping tool, a radial crimping die can also be used to obtain the point-type crimping structure of the present invention. Taking the radial crimping eight-petal die as an example, Figure 6 The front view of the radial crimping die is shown. Figure 7 As shown in the unfolded view of its inner wall, there is a pressing point on each petal of the mold. Looking along the circumference, there is only one pressing point on each circle.

[0036] The above-mentioned point-type crimping die is fully suitable for large-scale industrial production.

[0037] The advantages of the point-type buckling structure of the present invention are explained below using four buckling points as an example:

[0038] If it is an ordinary radial pressing structure, the four pressing points are on the same circumference, and the four pressing points form the medium flow resistance at four points, that is, the pressure drop at four points.

[0039] With the point-type clamping structure of the present invention, the four clamping points generate the same pull-out resistance as radial clamping. However, since the four clamping points are distributed along four circumferences, the medium encounters resistance at only one clamping point on each circumference, effectively reducing the pressure drop to one, or only one-quarter that of conventional radial clamping. Therefore, the point-type clamping structure of the present invention achieves the same pull-out resistance as radial clamping while significantly reducing the resistance to medium flow.

[0040] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A point-type crimping structure for a metal tube, characterized in that: The invention comprises a plurality of buckling points (1) distributed on the metal pipe, each buckling point (1) is on a different circumference, and there is only one buckling point (1) on each circumference.

2. The point-type crimping structure of the metal pipe according to claim 1, characterized in that: When viewed along the axial direction, any two buckling points (1) are not on the same element line.

3. The point-type crimping structure of the metal pipe according to claim 2, characterized in that: The number of the buckling points (1) is four, and the angle between adjacent buckling points (1) is 90°.

4. A point-type crimping method for a metal tube, used for processing the point-type crimping structure of the metal tube according to any one of claims 1 to 3, comprising a tool body (2) and a crimping screw (3), wherein the tool body (2) is a U-shaped structure, and a semicircular mold groove (21) for placing the metal tube (4) to be crimped is provided on the left side, and the crimping screw (3) is rotatably mounted on the right side of the tool body (2), the axis of the crimping screw (3) and the axis of the semicircular mold groove (21) are on the same plane and perpendicular to each other, one end of the crimping screw (3) is a crimping head (31), and the other end is a handle (32), characterized in that The following steps are also included: The first step is to place the metal tubes to be crimped together in the semicircular mold groove (21), and rotate the handle (32) of the crimping screw (3) so that the crimping head (31) is aligned with the metal tube to crimp out the first crimping point (1); Step 2: Rotate the handle (32) in the opposite direction to withdraw the pressing screw (3); Step 3: Push the metal tube forward along the axis to a certain length, rotate the metal tube, and rotate the handle (32) of the crimping screw (3) so that the crimping head (31) is aligned with the metal tube to crimp out the second crimping point (1); Step 4: Repeat steps 2 and 3 until all the crimping actions are completed.

5. The point-type crimping method for a metal pipe according to claim 4, characterized in that: In the third step, the metal tube is pushed forward along the axis of the metal tube for a certain length, and then the metal tube is rotated at a certain angle before being buckled.

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