A liquid nitrogen cooling process for online die extrusion of aluminum alloy profiles

Abstract

This invention relates to the field of aluminum alloy processing technology, and in particular to a liquid nitrogen cooling process for online extrusion dies of aluminum alloy profiles. The process includes the following steps: liquid nitrogen flows into the axial groove of the die sleeve inside the extrusion die mechanism through a connecting pipe, keeping the die pad stable between 450 and 550 degrees Celsius, and the die body between 500 and 600 degrees Celsius. A compressor directs coolant from the condenser into the cooling pipe through an external pipe. The condenser cools the die body, lowering its internal temperature to between 480 and 540 degrees Celsius. After the cooling pipe initially cools the die pad, some liquid nitrogen flows to the outside of the die pad, further cooling it and maintaining it at a stable temperature. Liquid nitrogen cooling, in conjunction with the cooling pipe, can reduce surface defects generated during extrusion, solving the problem of unsatisfactory cooling effects in existing liquid nitrogen cooling systems, which leads to surface defects such as oxidation and cracks during extrusion.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy processing technology, and in particular to an online liquid nitrogen cooling process for aluminum alloy profile extrusion dies. Background Technology

[0002] Currently, Chinese Patent Publication No. CN111346937B discloses a constant-temperature high-speed extrusion liquid nitrogen cooling device, including a frame, an extrusion die mechanism, two liquid nitrogen cylinders mounted on the frame, two output hoses respectively connected to the two liquid nitrogen cylinders, and nozzles located at the free ends of the two output hoses. The extrusion die mechanism is mounted on the frame, and a die body is installed at its output end. A die pad is installed on the side of the die body opposite to the extrusion die mechanism. The die body and the die pad are fixed to the outside by a die sleeve. The outside of the die sleeve has two embedding holes for installing the two nozzles. A circumferentially distributed section is formed on the inner wall of the die sleeve. The fabric has two circumferential grooves, which are respectively located at the two axial ends of the mold sleeve. Each of the circumferential grooves is connected to the embedding hole. Two sets of axial grooves are evenly distributed on the inner side wall of the mold sleeve. This discloses the cooling process of the previous application. The cooling process uses two liquid nitrogen cylinders to cool the mold body and the mold pad respectively. However, due to the certain gap between the mold pad and the mold pad, the temperature of the mold pad is not high. The amount of liquid nitrogen used in the left cylinder is not large. The temperature of the mold body is high when it is in use. Liquid nitrogen often cannot keep the mold body at a low temperature. The cooling effect is not ideal in actual use, resulting in surface defects such as oxidation and cracks during the extrusion process. Summary of the Invention

[0003] Therefore, in view of the above problems, the present invention proposes an online liquid nitrogen cooling process for aluminum alloy profile extrusion dies, which solves the problem that the cooling effect of existing liquid nitrogen cooling is not ideal in actual use, resulting in surface defects such as oxidation and cracks during the extrusion process.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a liquid nitrogen cooling process for online extrusion dies of aluminum alloy profiles, comprising the following steps:

[0005] The first step is to add liquid nitrogen into the liquid nitrogen cylinder. After completion, the liquid nitrogen flows into the axial groove of the mold sleeve inside the extrusion mold mechanism through the connecting pipe. The liquid nitrogen flows through the axial groove to the axial grooves on the top surface of the mold body and the top surface of the mold pad on both sides. At the same time, some of it flows into the annular cooling groove between the mold body and the mold pad, so that the mold pad is kept stable between 450 and 550 degrees and the mold body is kept between 500 and 600 degrees.

[0006] The second step is that the compressor draws the coolant from the condenser into the cooling pipe through the external pipe. The condenser cools the mold body down to 50-60 degrees Celsius, and the mold body temperature will be maintained between 480-540 degrees Celsius.

[0007] The third step involves using a lifting device to rotate and stand the extruded profile upright before sending it to an external conveyor line.

[0008] Furthermore, the extrusion die mechanism in the first step includes a die body, a die pad located on one side of the die body, and a die sleeve located on the outside of the die pad and the die body. An annular cooling groove is provided between the die body and the die pad, and an axial groove is provided between the die body, the die pad, and the die sleeve. The axial groove is connected to the annular cooling groove, and a connecting pipe is provided between the liquid nitrogen cylinder and the axial groove. Cooling pipes are provided inside the die body, and the cooling pipes are distributed in an annular pattern inside the die body. An external pipe is provided at the top of the die body and is connected to the ends of both sides of the cooling pipes. A compressor and a condenser are provided on the frame. The compressor is connected to the condenser. The external pipe on one side of the cooling pipe is connected to the compressor, and the external pipe on the other side of the cooling pipe is connected to the condenser.

[0009] Furthermore, in the third step, the lifting device includes a docking plate located on the side of the mold pad away from the mold body, a horizontal guide frame on the top of the docking plate, a vertical guide frame vertically located on one side of the horizontal guide frame, a horizontal slider slidably located within the horizontal guide frame, a vertical slider slidably located within the vertical guide frame, a guide plate rotatably connected to the horizontal slider, a rotating rod rotatably located on the side of the docking plate near the vertical guide frame and rotatably connected to the guide plate, a rotating shaft rotatably located on the side of the rotating rod away from the docking plate, a first motor for driving the rotating rod to rotate, a horizontal hole on the horizontal guide frame for inserting the rotating shaft, and a vertical hole on the vertical guide frame. The side of the mold pad away from the mold body is provided with a cutting device for cutting the profile, and the side of the mold pad away from the mold body is provided with a horizontal axis moving platform for driving the cutting device to move laterally. The horizontal side of the guide plate is rotatably connected to the horizontal slider, and the middle part of the guide plate is rotatably connected to the vertical slider. The rotating rod is rotatably connected to the guide plate between the horizontal slider and the vertical slider.

[0010] Furthermore, the cutting device includes a drive cylinder located at the front end of the horizontal axis moving platform, a cutter located at the bottom of the drive cylinder, and a support platform located below the cutter. The support platform and the drive cylinder are connected to the horizontal axis moving platform.

[0011] By adopting the aforementioned technical solution, the beneficial effects of the present invention are:

[0012] This online liquid nitrogen cooling process for aluminum alloy profile extrusion dies involves initial cooling of the die pad via cooling pipes. Some liquid nitrogen then flows to the outside of the die pad, further cooling it and maintaining a stable temperature. Liquid nitrogen cooling, in conjunction with cooling pipes, reduces surface defects during extrusion, such as oxidation and cracks, extending the die's lifespan. It also reduces thermal fatigue and extends the die's service life. Furthermore, when used in conjunction with annular and axial cooling grooves, it provides continuous cooling to the die, reducing the need for a separate liquid nitrogen cylinder and minimizing manual refilling. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the present invention;

[0014] Figure 2 This is a partial structural cross-sectional view of the present invention;

[0015] Figure 3 This is a front view schematic diagram of the lifting device structure of the present invention;

[0016] Figure 4 This is a partial structural diagram of the lifting device of the present invention;

[0017] Figure 5 This is a top view of the transverse axis moving platform structure of the present invention;

[0018] Figure 6 This is a schematic diagram of the horizontal axis moving platform structure of the present invention. Detailed Implementation

[0019] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0020] refer to Figures 1 to 6 This embodiment provides an online liquid nitrogen cooling process for aluminum alloy profile extrusion dies, including the following steps:

[0021] First, liquid nitrogen is added to the liquid nitrogen cylinder 2. After completion, the liquid nitrogen flows into the axial groove 35 in the mold sleeve 33 through the connecting pipe 36. The liquid nitrogen flows through the axial groove 35 to the axial groove 35 on the top surface of the mold body 31 and the axial groove 35 on the top surface of the mold pad 32 on both sides. At the same time, some of it flows to the annular cooling groove 34 between the mold body 31 and the mold pad 32, so that the mold pad 32 is kept stable between 450 and 550 degrees and the mold body 31 is kept between 500 and 600 degrees.

[0022] In the second step, the compressor 313 draws the coolant built into the condenser 314 into the cooling pipe 311 through the external pipe 312. The condenser 314 cools the mold body 31 down to 50-60 degrees Celsius, and the temperature of the mold body 31 will be maintained between 480-540 degrees Celsius.

[0023] The third step involves using the lifting device 5 to rotate and stand the extruded profile upright, then outputting it to the external conveyor line.

[0024] The compressor 313 draws coolant from the condenser 314 through the external pipe 312 into the cooling pipe 311. The condenser 314 cools the liquid nitrogen, lowering the operating temperature of the mold body 31. This structure includes a connection between the liquid nitrogen cylinder 2 and the mold sleeve 33 at the middle. The bottom of this connection is located between the mold pad 32 and the mold body 31. Liquid nitrogen flows through the axial groove 35 to both sides, cooling both the mold body 31 and the mold pad 32. Due to the high temperature of the mold pad 32, after the initial cooling by the cooling pipe 311, some liquid nitrogen flows to the outside of the mold pad 32, further cooling it and maintaining it at a stable temperature. Liquid nitrogen cooling, in conjunction with the cooling pipe, can reduce surface defects such as oxidation and cracks during extrusion, extending the life of the mold body and reducing thermal fatigue. Furthermore, when the cooling pipe is used in conjunction with the annular cooling groove and the axial groove, it provides continuous cooling to the mold body. This reduces the need for a separate liquid nitrogen cylinder, minimizing the need for repeated manual refilling.

[0025] The specific equipment includes a frame 1, an extrusion die mechanism 3 mounted on the frame 1, and a liquid nitrogen cylinder 2 mounted on the frame 1. The extrusion die mechanism 3 includes a die body 31, a die pad 32 located on one side of the die body 31, and a die sleeve 33 located outside the die pad 32 and the die body 31. An annular cooling groove 34 is provided between the die body 31 and the die pad 32. An axial groove 35 is provided between the die body 31, the die pad 32, and the die sleeve 33. The axial groove 35 is connected to the annular cooling groove 34. The liquid nitrogen cylinder 2 is connected to the axial groove 35. A connecting pipe 36 is provided; a cooling pipe 311 is provided inside the mold body 31, and the cooling pipe 311 is distributed in a ring inside the mold body 31. An external pipe 312 connected to the two ends of the cooling pipe 311 is provided on the top of the mold body 31. A compressor 313 and a condenser 314 are provided on the frame 1. The compressor 313 is connected to the condenser 314. The external pipe 312 on one side of the cooling pipe 311 is connected to the compressor 313, and the external pipe 312 on the other side of the cooling pipe 311 is connected to the condenser 314.

[0026] The mold pad 32 is provided with a lifting device 5 for lifting the profile on the side away from the mold body 31. The lifting device 5 includes a docking plate 501 located on the side of the mold pad 32 away from the mold body 31, a horizontal guide frame 502 located on the top of the docking plate 501, a vertical guide frame 503 vertically located on one side of the horizontal guide frame 502, a horizontal slider 504 slidably located in the horizontal guide frame 502, a vertical slider 505 slidably located in the vertical guide frame 503, a guide plate 506 rotatably connected to the horizontal slider 504, a rotating rod 507 rotatably located on the side of the docking plate 501 near the vertical guide frame 503 and rotatably connected to the guide plate 506, and a rotating shaft 508 rotatably located on the side of the rotating rod 507 away from the docking plate 501. The system includes a first motor 509 for driving the rotating rod 507 to rotate, a horizontal hole 510 on the horizontal guide frame 502 for inserting the rotating shaft 508, and a vertical hole 511 on the vertical guide frame 503. The mold pad 32 is provided with a cutting device 512 for cutting the profile on the side away from the mold body 31. The mold pad 32 is provided with a horizontal axis moving platform 513 for driving the cutting device 512 to move laterally on the side away from the mold body 31. The guide plate 506 is rotatably connected to the horizontal slider 504 on one side and to the vertical slider 505 in the middle. The rotating rod 507 is rotatably connected to the guide plate 506 between the horizontal slider 504 and the vertical slider 505.

[0027] The cutting device cuts the output profile. After cutting, the profile falls onto the top of the guide plate. The first motor runs, and the first motor drives the guide plate to flip upward through the rotating shaft on the rotating rod. The rotating rod moves from the horizontal hole on the horizontal guide frame to the vertical hole in the vertical guide frame. The horizontal slider moves to one side of the vertical guide frame, and the vertical slider moves upward. The guide plate flips upward and vertically. Then, the horizontal axis moving platform simultaneously drives the cutting device to move to the left, so that the profile falls into the gap between the guide plate and the cutting device. After cutting, the cutting device and the guide plate will support the left and right sides of the profile. The top of the profile is usually provided with a lifting hole. When the external conveying device passes by, it can directly lift the profile for transfer after cutting.

[0028] The cutting device 512 includes a drive cylinder 21 located at the front end of the horizontal axis moving platform 513, a cutter 22 located at the bottom of the drive cylinder 21, and a support platform 23 located below the cutter 22. The support platform 23 and the drive cylinder 21 are connected to the horizontal axis moving platform 513.

[0029] After the profile is output, the drive cylinder drives the cutter to move downwards. The cutter moves to the top surface of the support platform and cuts the profile.

[0030] The horizontal axis moving platform 513 includes a support frame 5a, an upper fixed frame 5b located on top of the support frame 5a, an upper slide rail 5c located on the top surface of the fixed frame, an upper sliding block 5d located on the top surface of the upper slide rail 5c, a lower fixed frame 5e located at the bottom of the support frame 5a, a conveyor belt 5f located within the fixed frame, a second motor 5g for driving the conveyor belt 5f to rotate, a lower slide rail 5h located on the lower fixed frame 5e, a lower sliding block 5i slidably located on the lower slide rail 5h, and a sliding plate 5j located between the upper sliding block 5d and the lower sliding block 5i. The sliding plate 5j is detachably connected to one side of the conveyor belt 5f. The drive cylinder 21 is located on the top of the sliding plate 5j, and the support platform 23 is located at the bottom of the sliding plate 5j.

[0031] During the leftward rotation of the guide plate 506, the second motor 5g drives the conveyor belt 5f to rotate. The conveyor belt 5f moves to the left via the lower sliding block 5i. The lower sliding block 5i drives the upper sliding block 5d to slide to the left via the slide plate 5j. Since the upper and lower slide rails and sliding blocks will simultaneously bear the load of the drive cylinder 21 and the support platform 23, the slide plate 5j will slide to the left more smoothly with balanced load bearing, and will not be easily damaged in the long term. The support platform 23 and the cutter 22 will also maintain a distance from the right side of the guide plate 506 and move to the left. The guide plate 506 will stand upright between the support platform 23 and the guide plate 506, which facilitates the output of the profile.

[0032] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0033] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0034] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0035] 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 that embodiment or example is included in at least one embodiment or example of the present invention. 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. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0036] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A liquid nitrogen cooling process for an online die in aluminum alloy profile extrusion, characterized in that, Includes the following steps: The first step involves adding liquid nitrogen to the liquid nitrogen cylinder. Afterward, the liquid nitrogen flows through a connecting pipe into the axial groove of the mold sleeve inside the extrusion die mechanism. The extrusion die mechanism includes a die body, a die pad located on one side of the die body, and a mold sleeve located outside the die pad and die body. An annular cooling groove is provided between the die body and the die pad, and an axial groove is provided between the die body, the die pad, and the mold sleeve. The axial groove is connected to the annular cooling groove. A connecting pipe is provided between the liquid nitrogen cylinder and the axial groove. Cooling pipes are provided inside the die body, and these cooling pipes are distributed in a ring around the die. Inside the main body, the top of the mold body is provided with an external pipe that is connected to the ends of both sides of the cooling pipe. The frame is provided with a compressor and a condenser. The compressor is connected to the condenser. The external pipe on one side of the cooling pipe is connected to the compressor, and the external pipe on the other side of the cooling pipe is connected to the condenser. Liquid nitrogen flows through the axial groove to the axial groove on the top surface of the mold body and the axial groove on the top surface of the mold pad on both sides. At the same time, some of it flows to the annular cooling groove between the mold body and the mold pad, so that the mold pad is kept stable between 450 and 550 degrees and the mold body is kept between 500 and 600 degrees. The second step is that the compressor draws the coolant from the condenser into the cooling pipe through the external pipe. The condenser cools the mold body down to 50-60 degrees Celsius, and the mold body temperature will be maintained between 480-540 degrees Celsius. The third step involves using a lifting device to rotate and stand the extruded profile upright before sending it to an external conveyor line.

2. The liquid nitrogen cooling process for an online die in aluminum alloy profile extrusion according to claim 1, characterized in that: In the third step, the lifting device includes a docking plate located on the side of the mold pad away from the mold body, a horizontal guide frame on the top of the docking plate, a vertical guide frame perpendicular to one side of the horizontal guide frame, a horizontal slider slidably disposed within the horizontal guide frame, a vertical slider slidably disposed within the vertical guide frame, a guide plate rotatably connected to the horizontal slider, a rotating rod rotatably disposed on the side of the docking plate near the vertical guide frame and rotatably connected to the guide plate, a rotating shaft rotatably disposed on the side of the rotating rod away from the docking plate, a first motor for driving the rotating rod to rotate, a horizontal hole disposed on the horizontal guide frame for inserting the rotating shaft, and a vertical hole disposed on the vertical guide frame. The side of the mold pad away from the mold body is provided with a cutting device for cutting the profile, and the side of the mold pad away from the mold body is provided with a horizontal axis moving platform for driving the cutting device to move laterally. The horizontal side of the guide plate is rotatably connected to the horizontal slider, and the middle part of the guide plate is rotatably connected to the vertical slider. The rotating rod is rotatably connected to the guide plate between the horizontal slider and the vertical slider.

3. The liquid nitrogen cooling process for an online die in aluminum alloy profile extrusion according to claim 2, characterized in that: The cutting device includes a drive cylinder located at the front end of the horizontal axis moving platform, a cutter located at the bottom of the drive cylinder, and a support platform located below the cutter. The support platform and the drive cylinder are connected to the horizontal axis moving platform.

4. The liquid nitrogen cooling process for an online die in aluminum alloy profile extrusion according to claim 3, characterized in that: The bottom surface of the cutter is V-shaped.

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