Ultrahigh pressure flexible punch assembly, die, system and method of operation

Abstract

The invention belongs to the field of powder compression molding, and particularly discloses an ultrahigh-pressure flexible punch assembly, a die, a system and an operation method. The flexible punch assembly comprises an upper pressing plate, a transition plate and a soft film. The upper pressing plate is fixedly connected with the transition plate and limits the soft film at a fixed position; a liquid inlet and outlet channel is formed in the upper pressing plate and communicated with the soft film and an external ultrahigh-pressure system. A die, a system and an operation method are further designed based on the flexible punch assembly. Compared with the prior art, high-pressure liquid can be injected to directly act on powder through the soft film to achieve rapid pressing of the powder. The ultrahigh-pressure flexible punch pressing technology can achieve pressing of special-shaped powder products, the requirement for multiple times of pressing of powder can be met, and the pressing quality of the powder is improved. And in combination with a powder vacuumizing technology, the powder pressing effect can be effectively improved.

Description

Technical Field

[0001] The invention relates to the field of powder pressing and forming, and in particular to an ultra-high pressure flexible punch assembly, a die, a system and an operating method. Background Art

[0002] Powder pressing is a manufacturing technology that processes powdered materials into solid workpieces with a certain shape and size through pressure. This process is widely used in the processing of various materials, such as high-temperature refractory materials, ceramics, cemented carbide, rare earth permanent magnets, carbon materials, metal powder molding, etc.

[0003] The powder pressing in the prior art is a rigid punch pressing, which is usually used for dry pressing. Specifically, a rigid punch is used to apply pressure to the powder to form it into the desired shape. The punch usually moves vertically, and the powder is compressed under the pressure of the punch and forms the final product through the holes of the mold. This method is simple and low-cost, but there are problems such as uneven density inside the pressed product and poor quality of the punching edge. Especially for special-shaped products (i.e., products with a small pressing mold entrance and a large middle), the rigid punch cannot achieve the corresponding function. Summary of the invention

[0004] The purpose of the present invention is to provide an ultra-high pressure flexible punch assembly, mold, system and operation method, which can inject high-pressure liquid to directly act on powder through a soft film to achieve rapid powder compression. The ultra-high pressure flexible punch compression technology can realize the compression of special-shaped powder products, and can also realize multiple compression requirements for powder, thereby improving the quality of powder compression. Combined with powder vacuum extraction technology, the powder compression effect can also be effectively improved.

[0005] The technical solution for achieving the purpose of the present invention is: a punching method of an ultra-high pressure flexible punch, which injects ultra-high pressure liquid into a soft film and then uses the soft film to realize powder pressing and molding.

[0006] An ultra-high pressure flexible punch assembly comprises a mounting unit and a soft film; the mounting unit is fixedly connected to the soft film; a liquid inlet and outlet channel is arranged on the mounting unit, connecting the inside of the soft film with an external ultra-high pressure system.

[0007] The installation unit comprises an upper pressing plate and a transition plate; the upper pressing plate is fixedly connected to the transition plate and restricts the soft film to a fixed position.

[0008] A protrusion with a circular cross-section is arranged around the opening of the soft film end of the flexible punch assembly, and the circular protrusion cooperates with the upper pressure plate and the transition plate to form a first sealing structure; a sealing ring is arranged between the upper pressure plate and the transition plate of the flexible punch assembly and outside the upper opening range of the soft film to form a second seal.

[0009] A mold, the ultra-high pressure flexible punch assembly.

[0010] The mold also includes a fastening sleeve and a forming mold; the forming mold is placed in the fastening sleeve cavity, and the powder is placed in the forming mold; the flexible punch assembly is fixedly connected to the fastening sleeve.

[0011] The mold also includes an opening pad and a base; two semicircular opening pads are placed at the lower part of the fastening sleeve, and the opening pads are fixed by connecting the base with the fastening sleeve; a protrusion is set in the middle of the base, and the top of the protrusion contacts the forming mold, which is used to separate the fastening sleeve and the base after pressing is completed.

[0012] An ultra-high pressure flexible punch pressing system and the die.

[0013] The ultra-high pressure flexible punch pressing system also includes an ultra-high pressure pressure system and a vacuum system; the vacuum system is connected to the mold gas circuit interface through a vacuum pipeline, and the vacuum system is used to make the space where the powder is located reach a certain vacuum degree; the ultra-high pressure system is used to transport liquid into the mold and recover excess liquid and maintain pressure, the ultra-high pressure system is connected to the inlet of the mold through an outlet pipeline, and the ultra-high pressure system is connected to the inlet of the mold through an inlet pipeline.

[0014] An operating method of an ultra-high pressure flexible punch pressing system specifically comprises the following steps:

[0015] S1: manually add powder into the forming die and lock the flexible punch assembly with the fastening sleeve;

[0016] S2: The vacuum system extracts the air from the outer cavity of the soft film and the powder to form a certain vacuum degree;

[0017] S3: The ultra-high pressure system delivers fluid to the inner cavity of the soft film, the inner cavity of the soft film is filled with fluid and the air is expelled, the ultra-high pressure system pressurizes to the design pressure, maintains the pressure, and then the soft film presses the powder, and releases the pressure after the pressing is completed;

[0018] S4: disconnect the vacuum system, the pumping system extracts the fluid in the soft film through the pressurized pipeline, and the soft film shrinks;

[0019] S5: If secondary pressing is required, disassemble the flexible punch assembly, add powder again and replace the soft film assembly, and repeat the pressing process of S1-S4;

[0020] S6: When withdrawing the material, extract the two opening pads. If the forming mold is not separated from the fastening sleeve, apply external force to the fastening sleeve to separate the forming mold from the fastening sleeve.

[0021] Compared with the prior art, the present invention has the following significant advantages: the present invention can realize the pressing of special-shaped powder products through the setting of the soft film in the flexible punch assembly; the formed products have high density and uniform density distribution; the leakage of high-pressure liquid is prevented by the setting of two sealing structures; and convenient mold opening and separation is achieved by the setting of the opening pad and the base. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The overall schematic diagram of the ultra-high pressure flexible punch pressing technology system provided by the present invention;

[0023] Figure 2 A schematic diagram of the principle of the ultra-high pressure flexible punch pressing technology system provided by the present invention;

[0024] Figure 3 A schematic diagram of the mold structure provided by the present invention;

[0025] Figure 4 A schematic diagram of the structure of the flexible punch assembly provided by the present invention;

[0026] Figure 5 This is an enlarged view of the sealing structure of the flexible punch assembly structure provided by the present invention.

[0027] Explanation of the reference numerals: 1-mold, 2-ultra-high pressure system, 3-vacuum system, 4-vacuum pipeline, 5-export pipeline, 6-inlet pipeline, 7-fluid box, 8-oil pump, 9-low-pressure pump, 10-high-pressure pump, 1-mold, 11-pressure relief valve, 12-high-pressure valve, 13-low-pressure valve, 14-pressure reducing valve, 15-air two-piece, 16-compressed air inlet. DETAILED DESCRIPTION

[0028] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those generally understood by those of ordinary skill in the art to which the present invention belongs.

[0029] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or other combinations.

[0030] like Figure 1 As shown, the present invention provides an ultra-high pressure flexible punch pressing system, including a mold 1, an ultra-high pressure pressure system 2, and a vacuum system 3.

[0031] The vacuum system 3 is connected to the gas circuit interface of the mold 1 through the vacuum pipeline 4, and the vacuum system 3 is used to make the space where the powder is located reach a certain vacuum degree.

[0032] The ultra-high pressure pressure system 2 is used to transport liquid into the mold and recover excess liquid and maintain pressure. The ultra-high pressure pressure system 1 is connected to the inlet of the mold 1 through the outlet pipeline 5, and the ultra-high pressure pressure system 1 is connected to the inlet of the mold 1 through the inlet pipeline 6. The ultra-high pressure pressure system 2 injects fluid into the inlet of the mold 1 through the outlet pipeline 5, and the fluid is transported to the soft film 111 through the internal channel of the mold. After filling the soft film 111, it flows out from the outlet of the mold 1 and flows back to the ultra-high pressure pressure system 2 through the inlet pipeline 6.

[0033] like Figure 2 As shown, the specific structure of the ultra-high pressure system 2 is as follows: the ultra-high pressure system 2 includes a fluid box 7, an oil pump 8, a low-pressure pump 9, a high-pressure pump 10, a pressure relief valve 11, a high-pressure valve 12, a low-pressure valve 13, a pressure reducing valve 14, an air two-piece 15 and a compressed air inlet 16. The compressed air inlet 16 is connected to the air two-piece 15 through a pipeline, and the air two-piece 15 is connected to the pressure reducing valve 14 through a pipeline; the low-pressure valve 13 is connected to the low-pressure pump 9 through a pipeline, and the high-pressure valve 12 is connected to the high-pressure pump 10 through a pipeline to form a parallel flow control path, one end of the parallel flow control path is connected to the pressure reducing valve 14 through a pipeline, and the other end is connected to the inlet pipeline 6 between the fluid box 7 and the mold 1, and the other end of the mold 1 is connected to the pressure relief valve 11 through an outlet pipeline 5, and the pressure relief valve 11 pipeline is connected to the oil pump 8, and the oil pump 8 is connected back to the fluid box 7 through a pipeline.

[0034] The pressure range of the ultra-high pressure system is: 150-300MPa.

[0035] When the ultra-high pressure system 2 is working, the low-pressure valve 13 is opened, the pressure relief valve 11 is opened, and the compressed air acts on the low-pressure pump 9 from the compressed air inlet 16 through the air coupler 15 and the pressure reducing valve 14. The low-pressure pump 9 works to pump the fluid from the fluid box 7 to the mold 1, and the fluid flows out from the outlet of the mold 1 and finally flows back to the fluid box 7. After the mold 1 is filled with fluid, the pressure relief valve 11 is closed, the low-pressure valve 13 is closed, the high-pressure valve 12 is opened, and the high-pressure pump 10 applies high-pressure pressure to the mold 1, and the powder in the mold is pressed. After a period of pressing, the high-pressure valve 12 is closed, the pressure relief valve 11 is opened, and the pressure is released, and one pressing is completed. The oil pump 8 extracts the fluid in the mold.

[0036] like Figure 3As shown, this embodiment discloses a mold including an ultra-high pressure flexible punch assembly, and the mold 1 includes a flexible punch assembly 101, a fastening sleeve 102, an opening pad 103, a base 104 and a forming die 105; the forming die 105 is placed in the mold cavity of the fastening sleeve 102, and the powder 106 is placed in the forming die 105. The flexible punch assembly 101 is fixedly connected to the fastening sleeve 102 by screws, and two semicircular opening pads 103 are placed at the lower part of the fastening sleeve 102, and the opening pads 103 are fixed by connecting the fastening sleeve 102 with the base 104. A protrusion is set in the middle of the base 104, and the top of the protrusion contacts the forming die 105, which is used to separate the fastening sleeve 102 from the base 104 after the pressing is completed.

[0037] During the first pressing, the powder 106 is first placed in the forming die 105, and then the flexible punch assembly 101 is installed on the fastening sleeve 102 and fixed. After the initial pressing is completed, the flexible punch assembly 101 is removed. When the pressing process requires multiple additions of powder, flexible punch assemblies 1 with different soft film 111 lengths (in the direction of gravity) can be set, and the flexible punch assemblies 1 with different soft film 111 lengths can be replaced according to the depth of the powder added multiple times, thereby achieving multiple rapid powder pressing. After the final pressing is completed, the two opening pads 103 are removed from both ends respectively, the fastening sleeve 102 moves downward due to its own weight, and the base 104 supports the forming die 105 to remain motionless, thereby separating the fastening sleeve 102 from the base 104.

[0038] like Figure 4 As shown, the flexible punch assembly 101 includes an upper pressing plate 107, a transition plate 108, a soft film 111, etc. The upper pressing plate 107 and the transition plate 108 are initially connected by bolts to restrict the soft film 111 to a fixed position. The upper pressing plate 107 is provided with a liquid inlet and outlet channel, and fluid connectors 109 are provided at both ends of the channel for connecting the inlet and outlet of the ultra-high pressure system pipeline. The high-pressure fluid flows into the channel through one end connector 109, and flows into the soft film 111 through the internal channel of the upper pressing plate 107. After the soft film 111 is filled, the fluid flows out from the other connector 109.

[0039] The transition plate 108 is provided with a vacuum interface 110 and a vacuum pumping pipeline; the vacuum interface 110 is connected to the external vacuum pumping system pipeline. The main function of the soft film 111 is to directly press the powder under the action of high-pressure liquid. The soft film 111 is close to the upper opening, and a protrusion with a circular (or semicircular) cross-section is arranged around the periphery. The circular protrusion cooperates with the upper pressing plate 107 and the transition plate 108 to form a first sealing structure to prevent leakage of high-pressure liquid in the soft film 111.

[0040] The material of the soft film 111 is nitrile rubber.

[0041] A sealing ring is provided between the upper pressing plate 107 and the transition plate 108 and outside the upper opening of the soft film 111 to form a second seal.

[0042] The present invention also discloses an operation method of an ultra-high pressure flexible punch pressing system, which specifically comprises the following steps:

[0043] S1: manually add powder into the forming die and lock the flexible punch assembly with the fastening sleeve;

[0044] S2: The vacuum system extracts the air from the outer cavity of the soft film and the powder to form a certain vacuum degree;

[0045] S3: The ultra-high pressure system delivers fluid to the inner cavity of the soft film, the inner cavity of the soft film is filled with fluid and the air is expelled, the ultra-high pressure system pressurizes to 150-300MPa, maintains the pressure, and then the soft film presses the powder, and releases the pressure after the pressing is completed;

[0046] S4: disconnect the vacuum system, and the pumping system extracts the fluid in the soft film through the pressurized pipeline, and the soft film becomes smaller;

[0047] S5: If secondary pressing is required, remove the flexible punch assembly, add powder again and replace the soft film assembly, and repeat the pressing process;

[0048] S6: When withdrawing the material, extract the two opening pads. If the forming mold is not separated from the fastening sleeve, an external force can be applied to the fastening sleeve to separate the forming mold from the fastening sleeve.

Claims

1. A punching method for an ultra-high pressure flexible punch, characterized in that: By injecting ultra-high pressure liquid into the soft film, the powder can be pressed and formed using the soft film.

2. An ultra-high pressure flexible punch assembly, characterized in that: The assembly comprises a mounting unit and a soft membrane; the mounting unit is fixedly connected to the soft membrane; a liquid inlet and outlet channel is arranged on the mounting unit, connecting the inside of the soft membrane with an external ultra-high pressure system.

3. The ultra-high pressure flexible punch assembly according to claim 2, characterized in that: The installation unit comprises an upper pressing plate and a transition plate; the upper pressing plate is fixedly connected to the transition plate and restricts the soft film to a fixed position.

4. The ultra-high pressure flexible punch assembly according to claim 2, characterized in that: A protrusion with a circular cross-section is arranged around the opening of the soft film end of the flexible punch assembly, and the circular protrusion cooperates with the upper pressure plate and the transition plate to form a first sealing structure; a sealing ring is arranged between the upper pressure plate and the transition plate of the flexible punch assembly and outside the upper opening range of the soft film to form a second seal.

5. A mold, characterized in that: The invention comprises the ultra-high pressure flexible punch assembly as described in any one of claims 1 to 3.

6. A mold according to claim 5, characterized in that: The mold also includes a fastening sleeve and a forming mold; the forming mold is placed in the fastening sleeve cavity, and the powder is placed in the forming mold; the flexible punch assembly is fixedly connected to the fastening sleeve.

7. A mold according to claim 6, characterized in that: The mold also includes an opening pad and a base; two semicircular opening pads are placed at the lower part of the fastening sleeve, and the opening pads are fixed by connecting the base with the fastening sleeve; a protrusion is set in the middle of the base, and the top of the protrusion contacts the forming mold, which is used to separate the fastening sleeve and the base after pressing is completed.

8. An ultra-high pressure flexible punch pressing system, characterized in that: The mold comprising claim 4.

9. The ultra-high pressure flexible punch pressing system according to claim 8, characterized in that: The ultra-high pressure flexible punch pressing system also includes an ultra-high pressure pressure system and a vacuum system; the vacuum system is connected to the mold gas circuit interface through a vacuum pipeline, and the vacuum system is used to make the space where the powder is located reach a certain vacuum degree; the ultra-high pressure system is used to transport liquid into the mold and recover excess liquid and maintain pressure, the ultra-high pressure system is connected to the inlet of the mold through an outlet pipeline, and the ultra-high pressure system is connected to the inlet of the mold through an inlet pipeline.

10. The method for operating an ultra-high pressure flexible punch pressing system according to claim 7, characterized in that: The specific steps include: S1: manually add powder into the forming die and lock the flexible punch assembly with the fastening sleeve; S2: The vacuum system extracts the air from the outer cavity of the soft film and the powder to form a certain vacuum degree; S3: The ultra-high pressure system delivers fluid to the inner cavity of the soft film, the inner cavity of the soft film is filled with fluid and the air is expelled, the ultra-high pressure system pressurizes to the design pressure, maintains the pressure, and then the soft film presses the powder, and releases the pressure after the pressing is completed; S4: disconnect the vacuum system, the pumping system extracts the fluid in the soft film through the pressurized pipeline, and the soft film shrinks; S5: If secondary pressing is required, disassemble the flexible punch assembly, add powder again and replace the soft film assembly, and repeat the pressing process of S1-S4; S6: When withdrawing the material, extract the two opening pads. If the forming mold is not separated from the fastening sleeve, apply external force to the fastening sleeve to separate the forming mold from the fastening sleeve.

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