Rotary aluminium tube hot extrusion die

Abstract

This invention relates to the field of extrusion dies, specifically disclosing a rotary aluminum tube hot extrusion die, comprising a male die and a female die fixedly connected. The male die includes a male die body, a die core disposed inside the male die body, and a die bridge disposed between the male die body and the die core. A flow divider is formed between the male die body, the die core, and the die bridge. The die bridge deflects clockwise or counterclockwise along the direction from the male die to the female die, and the extension line of the die bridge towards the die core deviates from the center line of the die core. The female die includes a female die body, a welding chamber, and a die hole. The welding chamber is recessed on the side of the female die body closest to the male die, and the die hole is connected to the end of the welding chamber away from the male die. The die core is inserted into the die hole, and a working zone is formed between the die hole and the die core. The welding chamber communicates with the working zone. Implementing this invention can improve the mechanical properties of aluminum tubes.

Description

Technical Field

[0001] This invention relates to the field of extrusion dies, and more particularly to a rotary aluminum tube hot extrusion die. Background Technology

[0002] Currently, aluminum tubes (i.e., aluminum alloy tubes) on the market include seamless tubes and ordinary tubes. Seamless tubes have good performance, but they are generally produced using the reverse extrusion method, which involves expensive equipment and high production costs. Ordinary tubes have low production costs, but their performance is inferior. Ordinary tubes are generally formed by forward extrusion using a flow-dividing combination die. This process results in weld lines on the finished ordinary tubes, which are relatively short. The aluminum alloy material near these weld lines is uneven, with poor crystal quality. Furthermore, the weld lines are directly opposite the center of the tube, causing the stress on the outer wall of the tube to act perpendicularly to the weld lines. Therefore, the weld lines are prone to corrosion and cracking under high pressure, becoming a weak point in the performance of ordinary tubes.

[0003] On the other hand, when using the forward hot extrusion method to extrude aluminum profiles with cavities, the flow-through die must have a core to fill the cavity, allowing metal to flow out from around the core and form the cavity. The core requires support from die bridges, a typical feature of flow-through dies, but these bridges can cause the extruded metal to split. The metal will only reassemble after entering the welding chamber, forming a weld line. The position, shape, and size of the weld line are closely related to the specific structure and size of the die bridges; generally, each die bridge corresponds to one weld line. Furthermore, the weld line is also influenced by other structures within the die. Therefore, designing the extrusion die is an effective way to improve the performance of aluminum tubes. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a rotary aluminum tube hot extrusion die, which can effectively improve the mechanical properties of aluminum tubes and enhance their pressure resistance and corrosion resistance.

[0005] To address the aforementioned problems, this invention discloses a rotary aluminum tube hot extrusion die, comprising a male die and a female die fixedly connected. The male die includes a male die body, a die core disposed inside the male die body, and a die bridge disposed between the male die body and the die core. A flow divider is formed between the male die body, the die core, and the die bridge. The die bridge deflects clockwise or counterclockwise along the direction from the male die to the female die, and the extension line of the die bridge towards the die core deviates from the center line of the die core.

[0006] The female mold includes a female mold body, a welding chamber, and a mold hole; the female mold body is recessed on the side near the male mold to form a welding chamber, the mold hole is connected to the end of the welding chamber away from the male mold, the mold core is inserted into the mold hole, a working zone is formed between the mold hole and the mold core, and the welding chamber is connected to the working zone.

[0007] As an improvement to the above technical solution, along the direction from the male mold to the female mold, the mold bridge includes an inlet mold bridge section, an intermediate mold bridge section, and an outlet mold bridge section;

[0008] The thickness of the inlet mold bridge is less than the thickness of the intermediate mold bridge, and the thickness of the outlet mold bridge is less than the thickness of the intermediate mold bridge.

[0009] As an improvement to the above technical solution, the thickness of the outlet mold bridge is less than the thickness of the inlet mold bridge.

[0010] As an improvement to the above technical solution, the number of diversion holes is 2 to 4, and the number of mold bridges is 2 to 4.

[0011] As an improvement to the above technical solution, the deflection angle of the outlet mold bridge relative to the inlet mold bridge is 15° to 30°.

[0012] As an improvement to the above technical solution, the side wall of the welding chamber and the rear wall of the welding chamber have a smooth transition;

[0013] The rear wall of the welding chamber includes at least one inclined section, which is inclined from the side closer to the male mold to the side closer to the working zone.

[0014] As an improvement to the above technical solution, the tilt angle of the tilted segment is 10° to 15°.

[0015] As an improvement to the above technical solution, a blocking part is provided on the rear wall of the welding chamber; the width of the blocking part is 1 / 12 to 1 / 8 of the length of the rear wall of the welding chamber; the height of the blocking part is 1 / 15 to 1 / 6 of the length of the side wall of the welding chamber.

[0016] As an improvement to the above technical solution, the sidewall of the blocking part on the side away from the working belt is inclined, and the inclination angle is 60° to 70°.

[0017] As an improvement to the above technical solution, the depth of the welding chamber is 1 / 4 to 2 / 5 of the thickness of the female mold.

[0018] Implementing this invention has the following beneficial effects:

[0019] In one embodiment of the present invention, a rotary aluminum tube hot extrusion die includes a fixedly connected male die and a female die. The male die includes a male die body, a die core, a die bridge, and flow dividers. The die bridge deflects clockwise or counterclockwise along the direction from the male die to the female die, and the extension line of the die bridge towards the die core deviates from the center line of the die core. In this embodiment, the die bridge is slightly curved in the front-to-back direction, forming a shape similar to a fan blade. Furthermore, the die bridge is not perpendicular to the die core and does not point towards the center of the die core. This structure allows the extruded metal flow to rotate clockwise or counterclockwise perpendicular to its flow direction under the guidance of the die bridge. This results in a curved weld line on the aluminum tube, increasing the bonding area of ​​the extruded metal flow in different flow dividers, significantly improving the bonding force, optimizing the crystal quality of the weld area, and greatly enhancing the mechanical properties, pressure resistance, and corrosion resistance of the extruded aluminum tube. Attached Figure Description

[0020] Figure 1 This is a front view of a rotating aluminum tube hot extrusion die in one embodiment of the present invention;

[0021] Figure 2 This is a cross-sectional view of a rotating aluminum tube extrusion die in one embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of the side wall, rear wall and blocking part of the welding chamber in one embodiment of the present invention;

[0023] Figure 4 This is a photograph of an aluminum tube obtained by extrusion using a rotary aluminum tube extrusion die in one embodiment of the present invention.

[0024] In the diagram, 1 represents the welding line, 100 represents the male mold, 110 represents the male mold body, 120 represents the mold core, 130 represents the mold bridge, 131 represents the inlet mold bridge section, 132 represents the intermediate mold bridge section, 133 represents the outlet mold bridge section, 140 represents the diversion hole, 200 represents the female mold, 210 represents the female mold body, 220 represents the mold hole, 221 represents the working zone, 300 represents the welding chamber, 310 represents the side wall of the welding chamber, 320 represents the rear wall of the welding chamber, 321 represents the inclined section, 400 represents the blocking section, and 410 represents the side wall of the blocking section. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining this application and are not intended to limit this application.

[0026] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0027] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly, for example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0028] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0029] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0030] Embodiments of this application provide a rotary aluminum tube hot extrusion die, which has a first direction, a second direction, and a third direction that are orthogonal to each other, wherein the first direction is defined as the left-right direction of the die (i.e., Figure 1 The second direction is defined as the front-to-back direction of the mold (i.e., the X direction). Figure 2 The Y-direction is defined, and the male die side is defined as the front, and the female die side as the rear, meaning that during extrusion, the extruded metal flows from the front to the rear. The third direction is defined as the up-down direction (i.e.,...). Figure 1, Figure 2 (in the Z direction).

[0031] See Figure 1 and Figure 2 In one embodiment of the present invention, a rotary aluminum tube hot extrusion die is provided, comprising a male die 100 and a female die 200 fixedly connected. The male die 100 includes a male die body 110, a die core 120, a die bridge 130, and a flow divider hole 140. The die core 120 is disposed inside the male die body 110, and the die bridge 130 is disposed between the male die body 110 and the die core 120 to support the die core 120. The flow divider hole 140 is formed between the male die body 110, the die core 120, and the die bridge 130, serving as a channel for the extruded metal flow. Along the direction from the male die 100 to the female die 200 (i.e., from the front to the rear of the hot extrusion die), the die bridge 130 deflects clockwise or counterclockwise, and the extension line of the die bridge 130 toward the die core 120 deviates from the centerline of the die core 120. The female mold 200 includes a female mold body 210, a welding chamber 300, and a mold hole 220. The female mold body 210 is recessed on the side near the male mold 100 to form the welding chamber 300. The mold hole 220 is located inside the female mold body 210 and penetrates through the female mold body 210. One end of the female mold 200 is connected to the welding chamber 300. The mold core 120 is inserted into the mold hole 220. A working zone 221 is formed between the mold hole 220 and the mold core 120. The welding chamber 300 is connected to the working zone 221.

[0032] In this embodiment, the mold bridge 130 deflects clockwise or counterclockwise, meaning it is slightly curved in the front-to-back direction (direction from the male mold 100 to the female mold 200), forming a shape similar to a fan blade. Furthermore, in the direction from the male mold body 110 to the mold core 120, the extension line of the mold bridge 130 deviates from the center line of the mold core 120, meaning the mold bridge 130 is not completely perpendicular to the mold core 120 and does not point towards the center of the mold core 120. This structure allows the extruded metal flow to rotate clockwise or counterclockwise perpendicular to its flow direction under the guidance of the mold bridge 130, thereby causing the weld line of the aluminum tube to also exhibit a curved shape (see...). Figure 4 This method increases the bonding area of ​​the extruded metal flow in different flow channels 140, significantly improving the bonding force and optimizing the crystal quality of the welded area. This results in a substantial improvement in the mechanical properties, pressure resistance, and corrosion resistance of the extruded aluminum tube. It should be noted that the traditional die bridge 130 has a straight wall in its front-to-back direction, and its perpendicularity to the die core 120 (i.e., its extension line passes through the center of the cross-section of the die core 120). This causes the extruded metal flow to only flow forward in the flow channels 140 without rotation, resulting in a straight weld line and a small bonding area, leading to poor mechanical properties of the extruded aluminum tube. This embodiment effectively solves this problem.

[0033] Specifically, in some embodiments, the male mold 100 and the female mold 200 are fixedly connected by connecting screws or the like, but this is not the only method. Before the male mold 100 and the female mold 200 are fixedly connected, they can also be assembled and positioned by locating pins.

[0034] Specifically, in some embodiments, the cross-section (the cross-section parallel to the XZ plane) of the diversion hole 140 is circular, fan-shaped, waist-shaped, or other irregularly shaped, but is not limited thereto. Preferably, in some embodiments, see [reference needed]. Figure 1 The cross-section of the diversion hole 140 is fan-shaped. This shape of the diversion hole 140 can effectively balance the flow rate of the extruded metal flow, reduce turbulence, and make the extruded metal flow appear as a rotating flow in the die hole 220, which further optimizes the mechanical properties, pressure resistance and corrosion resistance of the aluminum tube.

[0035] Specifically, in some embodiments, the number of diversion holes 140 is ≤ 5. Too many diversion holes 140 result in more weld lines in the extruded aluminum tube, leading to a decrease in its mechanical properties, pressure resistance, and corrosion resistance. However, if the number of diversion holes 140 is ≥ 2, firstly, too few diversion holes 140 result in uneven flow rate of the extruded metal, which is detrimental to welding; secondly, too few diversion holes 140 also lead to a decrease in production efficiency. Preferably, in some embodiments, the number of diversion holes 140 is 2 to 4. More preferably, it is 2 to 3.

[0036] Specifically, in some embodiments, the die core 120 is a cylindrical die core 120, a conical die core 120, or a boss-shaped die core 120, but is not limited thereto. Preferably, in some embodiments, the die core 120 is a conical die core 120. This shape of the die core 120 can further optimize the flow direction of the extruded metal flow and reduce the width of the weld line; moreover, this shape of the die core 120 can optimize the strength of the extrusion die, further reduce the number of die bridges 130, and thus reduce the number of weld lines in the aluminum tube, further improving the mechanical properties, pressure resistance, and corrosion resistance of the aluminum tube.

[0037] Specifically, in some embodiments, the cross-section of the mold bridge 130 (i.e., the cross-section parallel to the XZ plane) is rectangular, chamfered rectangular, teardrop-shaped, or trapezoidal, but is not limited to these. Preferably, in some embodiments, the cross-section of the mold bridge 130 is trapezoidal, that is, its thickness on the side near the mold core 120 is less than its width on the side near the male mold body 110, and the mold bridge 130 has arc-shaped transition portions at both ends near the male mold body 110 and near the mold core 120. Based on this cross-sectional shape of the mold bridge 130, the flow diversion hole 140 can be wider on the side near the male mold body 110, optimizing the rotation of the extruded metal flow and further improving the mechanical properties, pressure resistance, and corrosion resistance of the aluminum tube.

[0038] Specifically, in some embodiments, the thickness of each cross-section (i.e., the cross-section parallel to the XY plane) of the mold bridge 130 in the direction from the male mold 100 to the female mold 200 is the same, with only the cross-sectional thickness varying, but this is not limited to this. Preferably, in some embodiments, the thickness of the mold bridge 130 in the direction from the male mold 100 to the female mold 200 exhibits a trend of first gradually increasing and then gradually decreasing, i.e., it is spindle-shaped. This structure can strengthen the support for the mold core 120, thereby allowing this embodiment to further reduce the number of mold bridges 130, reduce the number of aluminum tube welding lines, and improve the mechanical properties, pressure resistance, and corrosion resistance of the aluminum tube.

[0039] More specifically, in the direction from the male mold 100 to the female mold 200, the mold bridge 130 includes an inlet mold bridge portion 131, an intermediate mold bridge portion 132, and an outlet mold bridge portion 133. See also Figure 1 The thickness of the inlet die bridge 131 is less than the thickness of the intermediate die bridge 132, and the thickness of the outlet die bridge 133 is less than the thickness of the intermediate die bridge 132. This structure not only further reduces the number of die bridges 130 but also optimizes the flow of the extruded metal. Specifically, the smaller thickness of the inlet die bridge 131 reduces extrusion pressure, facilitates splitting the metal flow, and makes it easier for the metal to flow into the diversion orifice 140, thus improving extrusion efficiency. The larger thickness of the intermediate die bridge 132 increases the flow rate of the extruded metal, strengthens the rotational tendency, and also improves the strength of the die bridge 130. The smaller thickness of the outlet die bridge 133 facilitates the gradual welding of the diverted metal, optimizing the mechanical properties, pressure resistance, and corrosion resistance of the aluminum tube.

[0040] More preferably, in some embodiments, the thickness of the outlet mold bridge portion 133 is less than the thickness of the inlet mold bridge portion 131, which makes the metal flow speed slower in the area near the outlet of the diversion hole 140, optimizes the welding effect, makes the weld line thinner and shorter, and further optimizes the mechanical properties of the aluminum tube.

[0041] Specifically, in the direction from the outer wall of the male die 100 to the die core 120, the conventional die bridge 130 is perpendicular to the die core 120 and points towards the center of the die core 120. However, this invention employs a slightly curved die bridge 130 that does not point towards the center line of the die core 120 to enhance the rotational tendency of the extruded metal flow. This results in the die bridge 130 and the outer wall of the die core 120 forming a certain angle that is not 90°. Preferably, in some embodiments, the exit die bridge portion 133 is tangent or approximately tangent to the outer wall of the die core 120, which makes the weld line thinner and less noticeable.

[0042] Specifically, in some embodiments, the number of die bridges 130 is 2 to 5. Increasing the number of die bridges 130, i.e., increasing the number of diversion holes 140, means more weld lines and a deterioration in the mechanical properties of the aluminum tube; conversely, too few die bridges 130 can easily lead to low extrusion efficiency and poor welding. Preferably, the number of die bridges 130 is 2 to 4. It should be noted that the multiple die bridges 130 deflect in the same direction (clockwise or counterclockwise). Furthermore, the multiple die bridges 130 are evenly distributed circumferentially along the die core 120.

[0043] Specifically, in some embodiments, the deflection angle of the outlet die bridge portion 133 relative to the inlet die bridge portion 131 is 15° to 40°. When the deflection angle is too large, the flow rate of the extruded metal flow in the diversion hole 140 is too slow, which is not only detrimental to improving extrusion efficiency but also to welding. When the deflection angle is too small, it is difficult to effectively form an extruded metal flow with a rotational tendency, and it is difficult to form a curved weld line. Preferably, the deflection angle of the outlet die bridge portion 133 relative to the inlet die bridge portion 131 is 15° to 30°, which can result in higher extrusion efficiency and better mechanical properties of the extruded aluminum tube.

[0044] Specifically, the welding chamber 300 is a cavity structure formed by a recess behind the female mold 200, and its cross-section is circular or butterfly-shaped, but not limited to these. It is preferably circular, which is more conducive to maintaining the rotational trend of the extruded metal flow, increasing the curvature of the weld line, increasing the contact area, and improving the mechanical properties of the aluminum tube.

[0045] Preferably, in some embodiments, the side wall 310 of the welding chamber and the rear wall 320 of the welding chamber form a smooth transition. This structure can reduce extrusion resistance and optimize the welding quality of the welding line.

[0046] Preferably, in some embodiments, the rear wall 320 of the welding chamber includes an inclined section 321 that slopes from the side near the male mold 100 toward the side near the working belt 221. By introducing the inclined section 321, the pressure inside the welding chamber 300 can be increased, optimizing metal welding. At the same time, the flow rate of the extruded metal flow can be increased before entering the working belt 221, thereby generating agitation of the metal flow, improving the uniformity of mixing, and making the weld line thinner and shorter.

[0047] Specifically, in some implementations, the tilt angle of the tilt segment 321 (i.e., Figure 3 The angle of inclination (α) is 10° to 15°. When the inclination angle is too large, the flow rate is too fast, the flatness of the aluminum tube wall after extrusion decreases, and roughness defects are easily generated. When the inclination angle is too small, the mixing is insufficient, and it is difficult to effectively shorten the weld line.

[0048] Preferably, see Figure 3In some embodiments, a blocking part 400 is provided on the rear wall 320 of the welding chamber, which protrudes from the rear wall 320 of the welding chamber in the direction of the sun mold 100. By introducing the blocking part 400, the pressure can be further increased, the stirring effect can be optimized, and the welding line can be made thinner and shorter.

[0049] Specifically, the width of the blocking part 400 (i.e., the width of its cross-section) is 1 / 12 to 1 / 8 of the length of the rear wall 320 of the welding chamber, and the height of the blocking part 400 (i.e., the height of its protrusion toward the male mold 100) is 1 / 15 to 1 / 6 of the length of the side wall 310 of the welding chamber. By controlling the width and height of the blocking part 400 as described above, the bending degree of the weld line can be increased while optimizing the stirring effect, thereby further improving the mechanical properties of the aluminum tube.

[0050] Preferably, in some embodiments, the sidewall 410 of the blocking portion on the side away from the working belt 221 is inclined, and its inclination angle (i.e. Figure 3 The angle of β is 60° to 70°. By setting it as described above, the weld line can be made shorter.

[0051] Preferably, in some embodiments, the depth of the welding chamber 300 (i.e., its depth in the Y direction) is 1 / 4 to 2 / 5 of the thickness of the female mold 200. It should be noted that although introducing the inclined section 321 and the blocking part 400 into the welding chamber 300 can effectively increase the welding pressure and improve the uniformity of stirring, it will also change the flow direction of the metal flow. Therefore, the present invention increases the depth of the welding chamber 300 to ensure a reasonable distribution of the weld line.

[0052] In summary, based on the rotary aluminum tube hot extrusion die of the above embodiments of the present invention, firstly, aluminum tubes can be produced using a forward extrusion method, reducing production costs, and the performance level of the aluminum tubes obtained by the present invention is comparable to that of traditional seamless aluminum tubes. Secondly, the hot extrusion die can obtain curved welds, increasing the area of ​​the weld contact surface and improving the mechanical properties of the aluminum tube. This effectively solves the problem that traditional aluminum tubes are prone to cracking along the weld line under high pressure. Thirdly, through the structural design of the hot extrusion die, while improving welding performance, it also ensures that the extruded metal flow has high flow efficiency, ensuring high production efficiency. Fourthly, through the design of the specific structure of the welding chamber 300, the outflow path of the metal flow is optimized, and the metal welding is optimized, resulting in high weld line density and uniformity, further improving the mechanical properties, pressure resistance, and corrosion resistance of the aluminum tube.

[0053] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with the described embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0054] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A rotary aluminum tube hot extrusion die, characterized in that, The device includes a male mold and a female mold that are fixedly connected. The male mold includes a male mold body, a mold core disposed inside the male mold body, and a mold bridge disposed between the male mold body and the mold core. A flow divider is formed between the male mold body, the mold core, and the mold bridge. The mold bridge deflects clockwise or counterclockwise along the direction from the male mold to the female mold, and the extension line of the mold bridge toward the mold core deviates from the center line of the mold core. The female mold includes a female mold body, a welding chamber, and a mold hole; the female mold body has a recessed welding chamber on the side near the male mold, the mold hole is connected to the end of the welding chamber away from the male mold, the mold core is inserted into the mold hole, a working zone is formed between the mold hole and the mold core, and the welding chamber is connected to the working zone; a blocking part is provided on the rear wall of the welding chamber; the width of the blocking part is 1 / 12 to 1 / 8 of the length of the rear wall of the welding chamber; the height of the blocking part is 1 / 15 to 1 / 6 of the length of the side wall of the welding chamber, and the side wall of the blocking part away from the working zone is inclined at an angle of 60° to 70°; Along the direction from the male mold to the female mold, the mold bridge includes an inlet mold bridge section, an intermediate mold bridge section, and an outlet mold bridge section; the deflection angle of the outlet mold bridge section relative to the inlet mold bridge section is 15°~30°; the thickness of the inlet mold bridge section is less than the thickness of the intermediate mold bridge section, the thickness of the outlet mold bridge section is less than the thickness of the intermediate mold bridge section, and the thickness of the outlet mold bridge section is less than the thickness of the inlet mold bridge section.

2. The rotary aluminum tube hot extrusion die as described in claim 1, characterized in that, The number of diversion holes is 2 to 4, and the number of mold bridges is 2 to 4.

3. The rotary aluminum tube hot extrusion die as described in claim 1, characterized in that, The side wall of the welding chamber and the rear wall of the welding chamber form a smooth transition; The rear wall of the welding chamber includes at least one inclined section, which is inclined from the side closer to the male mold to the side closer to the working zone.

4. The rotary aluminum tube hot extrusion die as described in claim 3, characterized in that, The tilt angle of the inclined section is 10°~15°.

5. The rotary aluminum tube hot extrusion die as described in claim 1, characterized in that, The depth of the welding chamber is 1 / 4 to 2 / 5 of the thickness of the female mold.

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