A method for continuous high-temperature and ultra-high-pressure uniform densification of powder materials

Abstract

This invention relates to a method for continuous high-temperature and ultra-high-pressure uniform densification of powder materials. It employs three winding pressure cylinders, corresponding to three working states: high-pressure densification, heating and pressing, and material handling. During production, a constant-temperature oil bath and high-temperature heating elements heat the winding pressure cylinders. A gantry press applies pressure to the inside of the winding pressure cylinders in the high-pressure densification state, thereby densifying the powder material under high-temperature and high-pressure conditions. Simultaneously, a hydraulic linear drive mechanism moves the constant-temperature oil bath reciprocating linearly, alternating the working states of the three winding pressure cylinders. This alternation process enables the powder material to be formed on an assembly line. The advantages of this invention are: it enables continuous, uniform, and dense production of powder materials under high-temperature and high-pressure conditions, resulting in safe, reliable, low-cost, and highly efficient production.

Description

Technical Field

[0001] This invention relates to the field of powder molding technology, specifically to a method for continuous high-temperature and ultra-high-pressure uniform densification of powder. Background Technology

[0002] A warm isostatic press is a material forming device based on Pascal's law, which uses a liquid as a medium to apply uniform pressure in all directions to a material at high temperature, thereby achieving the densification of powder.

[0003] Existing isostatic pressing (WHP) equipment requires multiple sequential steps during production, including opening the cylinder head, loading the product, heating and pressurizing, holding the temperature and pressure, cooling and depressurizing, opening the end cover, and removing the product. This process is time-consuming and cannot achieve continuous material forming. Since WHP presses have a working cylinder containing a high-temperature, high-pressure fluid, the working cylinder must be sealed during operation. Furthermore, after opening the end cover to load the material, the end cover must be reliably closed for normal operation. The heating and pressurizing, as well as cooling and depressurizing processes, are relatively slow. Therefore, the equipment is unsuitable for assembly line operation and suffers from low production efficiency. To improve efficiency, current methods involve increasing the volume of the working cylinder to increase the throughput per cycle. However, this method introduces problems such as increased costs and technical complexity due to the larger working pressure cylinder volume. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for continuous high temperature and ultra-high pressure uniform densification of powder, which can realize the continuous uniform and dense production of powder under high temperature and high pressure conditions, and the production is safe, reliable, low cost and high efficiency.

[0005] The objective of this invention is achieved through the following technical solution: A method for continuous high-temperature and ultra-high-pressure uniform densification of powder includes: Three winding pressure cylinders are fixed in an oil constant temperature pool containing oil, so that the three winding pressure cylinders correspond to three working states: high pressure densification treatment, heating and waiting for pressure, and material handling. The powder to be pressed is loaded into a flexible inner sleeve and sealed. Then the flexible inner sleeve is placed into a sealed sleeve filled with constant temperature oil. Finally, the sealed sleeve is placed into a winding pressure cylinder. The oil in the constant temperature tank is heated by a high-temperature heating element, so that the oil temperature rises to the set value and is maintained at a constant temperature. The hydraulic linear drive mechanism drives the oil constant temperature tank to move back and forth linearly, so that the working state of the three winding pressure cylinders alternates. During the alternation, the gantry press drives the sealed piston to pressurize the inside of the winding pressure cylinder in the high-pressure densification state, so as to densify the powder. The winding pressure cylinder in the heating and waiting-to-press state is heated and kept warm by the oil in the oil constant temperature tank. The molding material in the winding pressure cylinder in the material loading and unloading state is taken out and new powder is put in.

[0006] Furthermore, the gantry press, hydraulic linear drive mechanism, and multi-channel hydraulic station are all mounted on the base.

[0007] Furthermore, the hydraulic linear drive mechanism includes a linear slide rail, a slide block, and a drive cylinder. The linear slide rail is mounted on a base below the gantry press, the slide block is slidably mounted on the linear slide rail, the constant temperature oil bath is fixed on the slide block, and the drive cylinder is mounted on the base on both sides of the linear slide rail. The extension rod of the drive cylinder is connected to the slide block.

[0008] Furthermore, the base is equipped with a multi-channel hydraulic station, and the gantry press and drive cylinder are connected to the multi-channel hydraulic station through oil circuits.

[0009] Furthermore, the heating element is located in the constant temperature oil bath and is arranged around the pressure cylinder.

[0010] Furthermore, the winding pressure cylinder includes a pressure cylinder body and a steel strip. The pressure cylinder body is fixed in a constant temperature oil bath, and the steel strip is wound around the periphery of the pressure cylinder body.

[0011] Furthermore, the sealing sleeve includes an outer sleeve and an outer sleeve cover. The outer sleeve is located inside the pressure cylinder and is filled with constant temperature oil. The outer sleeve cover is connected to the outer sleeve by threads for sealing. The flexible inner sleeve is placed inside the outer sleeve.

[0012] Furthermore, the cylinder diameter of the gantry press is larger than the inner diameter of the pressure cylinder body.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention employs three winding pressure cylinders corresponding to three working states: high-pressure densification, heating and pressing, and material loading / unloading. During production, powder is placed into the winding pressure cylinders, which are then heated in a constant-temperature oil bath by high-temperature heating elements. A hydraulic linear drive mechanism drives the constant-temperature oil bath to move back and forth linearly, allowing the three winding pressure cylinders to alternate their working states. During this alternation, a gantry press can be used to pressurize the winding pressure cylinders in the high-pressure densification state, densifying the powder. The winding pressure cylinders in the heating and pressing state are kept warm in the constant-temperature oil bath, awaiting subsequent pressurization. The molded material in the winding pressure cylinders in the material loading / unloading state can be removed and new powder can be added, thus achieving continuous material molding production, forming an assembly line operation, and improving production efficiency.

[0014] 2. This invention enables continuous material forming production through the cooperation of multiple devices such as a gantry press, an oil constant temperature tank, multiple winding pressure cylinders, and a hydraulic linear drive mechanism. The total value of the entire set of equipment is lower than that of the traditional isostatic press, and the structure is more stable and reliable, thus reducing production costs.

[0015] 3. This invention uses an oil constant temperature pool and a high temperature heating element to heat and keep the winding pressure cylinder warm. Compared with the traditional isostatic press, it has lower power consumption, reduces production energy consumption, and helps to further reduce production costs. Attached Figure Description

[0016] Figure 1 This is a three-dimensional schematic diagram of the overall structure of the present invention; Figure 2 This is a top view of the overall structure of the present invention; Figure 3 for Figure 2 A schematic diagram of the cross-sectional structure along the AA direction; Figure 4 for Figure 3 Enlarged schematic diagram of the structure at point B in the diagram.

[0017] In the diagram: 1. Oil constant temperature tank; 2. Winding pressure cylinder; 3. Flexible inner sleeve; 4. High temperature heating element; 5. Gantry press; 6. Sealed piston; 7. Base; 8. Linear slide rail; 9. Slide block; 10. Drive cylinder; 11. Multi-channel hydraulic station; 12. Outer sleeve; 13. Outer sleeve cover. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0019] like Figures 1-4As shown, a powder uniform densification processing device includes an oil constant temperature tank 1, a winding pressure cylinder 2, a flexible inner sleeve 3, a sealing sleeve, a high-temperature heating element 4, a gantry press 5, and a hydraulic linear drive mechanism. The hydraulic linear drive mechanism is located below the gantry press 5. The oil constant temperature tank 1 is mounted on the hydraulic linear drive mechanism and is filled with oil. The high-temperature heating element 4 is located inside the oil constant temperature tank 1. The flexible inner sleeve 3 is located inside the sealing sleeve, and the sealing sleeve is located inside the winding pressure cylinder 2.

[0020] The powder is filled into the flexible inner sleeve 3 and sealed. Then, constant temperature oil is filled into the sealing sleeve and the flexible inner sleeve is sealed inside the sealing sleeve. Next, the sealing sleeve is placed in the winding pressure cylinder 2. The oil in the constant temperature pool 1 is heated by the high temperature heating element 4. The high temperature of the oil is transferred to the inside of the pressure cylinder of the winding pressure cylinder 2, thereby heating the sealing sleeve, the flexible inner sleeve 3 and the powder therein. Then, the inside of the winding pressure cylinder 2 is pressurized by the gantry press 5, thereby densifying the powder under high temperature and high pressure conditions.

[0021] like Figure 1 As shown, three winding pressure cylinders 2 are fixed inside the oil constant temperature tank 1. During production, the three winding pressure cylinders 2 correspond to three working states: high-pressure densification, heating and pressing, and material loading / unloading. Then, the oil constant temperature tank 1 is driven to move back and forth linearly through a hydraulic linear drive mechanism, thereby changing the working state of the three winding pressure cylinders 2. During the rotation, the gantry press 5 acts on the winding pressure cylinder 2 in the high-pressure densification state, thereby performing real-time high-pressure densification on the powder. The winding pressure cylinder 2 in the heating and pressing state is used to add powder for processing. The winding pressure cylinder 2 in the material loading / unloading state is used to remove the formed material and add new powder. Finally, by rotating the working states of the three winding pressure cylinders 2, the powder is continuously and uniformly densified under high temperature and high pressure conditions, forming an assembly line operation.

[0022] Based on the above-mentioned powder uniform densification equipment, the present invention also discloses a method for continuous high-temperature and ultra-high-pressure uniform densification of powder, comprising the following steps S1-S4: S1, such as Figure 1 As shown, three winding pressure cylinders 2 are fixed in an oil constant temperature pool 1 containing oil, so that the three winding pressure cylinders 2 correspond to three working states: high pressure densification treatment, heating and waiting for pressure, and material handling.

[0023] Among them, the winding pressure cylinder 2 in the high-pressure densification state is used for real-time high-pressure densification of powder, the winding pressure cylinder 2 in the heating and waiting-to-press state is used for adding powder and waiting to be processed, and the winding pressure cylinder 2 in the material picking and placing state is used to take out the formed material and put in new powder. In this way, by rotating the working state of the three winding pressure cylinders 2, assembly line operation can be realized.

[0024] The winding pressure cylinder 2 includes a pressure cylinder body and a steel strip. The pressure cylinder body is fixed in the oil constant temperature pool 1, and the steel strip is wound around the outside of the pressure cylinder body. Through the winding of the steel strip, the pressure cylinder can withstand ultra-high pressure of more than 600MPa.

[0025] S2, such as Figure 4 As shown, the powder to be pressed is loaded into the flexible inner sleeve 3 and sealed. Then the flexible inner sleeve 3 is placed into the sealing sleeve filled with constant temperature oil. Finally, the sealing sleeve is placed into the winding pressure cylinder 2.

[0026] The sealing sleeve includes an outer sleeve 12 and an outer sleeve cap 13, with the outer sleeve cap 13 connected to the outer sleeve 12 via threads for a sealing connection. The outer sleeve cap 13 is opened, and constant-temperature oil is filled into the outer sleeve 12. A flexible inner sleeve 3 containing powder is then placed inside the outer sleeve 12. The outer sleeve cap 13 is then screwed on to seal the flexible inner sleeve 3 within the outer sleeve 12. The sealing sleeve is then placed into the pressure cylinder. A sharp-edge sealing design can be used at the connection between the outer sleeve cap 13 and the outer sleeve 12 to further and effectively prevent leakage of the constant-temperature oil.

[0027] S3. The oil in the constant temperature oil bath 1 is heated by the high temperature heating element 4, so that the oil temperature rises to the set value and is kept constant.

[0028] like Figure 3 , Figure 4 As shown, the heating elements are located within the constant temperature oil bath 1 and surround the winding pressure cylinders 2. Since the three winding pressure cylinders 2 are always immersed in the oil in the constant temperature oil bath 1, the high temperature of the oil, after being heated by the heating elements, is transferred to the inside of the pressure cylinder body of the winding pressure cylinders 2, thereby heating the sealing sleeve, the flexible inner sleeve 3, and the powder material therein, achieving high-temperature densification treatment. The high-temperature heating element can be achieved using existing technologies such as heating rods or heat conduction by flowing the high-temperature medium through pipes via a mold temperature controller to heat the oil.

[0029] S4. The hydraulic linear drive mechanism drives the oil constant temperature tank 1 to move back and forth in a linear motion, so that the working state of the three winding pressure cylinders 2 is rotated. During the rotation process, the gantry press 5 presses the inside of the winding pressure cylinder 2 which is in a high-pressure densification state. Combined with the high temperature environment in the oil constant temperature tank 1, the powder is densified under high temperature and high pressure conditions.

[0030] like Figure 1 , Figure 2 As shown, the gantry press 5, the hydraulic linear drive mechanism, and the multi-channel hydraulic station 11 are all mounted on the base 7. The multi-channel hydraulic station 11 is also mounted on the base 7. The gantry press 5 and the hydraulic linear drive mechanism are connected to the multi-channel hydraulic station 11 through oil circuits, thereby driving the gantry press 5 and the hydraulic linear drive mechanism to work together.

[0031] like Figure 1 As shown, the hydraulic linear drive mechanism includes a linear slide rail 8, a slide block 9, and a drive cylinder 10. The linear slide rail 8 is fixed on the base 7 below the gantry press 5. The slide block 9 is slidably mounted on the linear slide rail 8. The oil constant temperature tank 1 is fixed on the slide block 9. The drive cylinder 10 is fixed on the base 7 on both sides of the linear slide rail 8 and connected to a multi-channel hydraulic station 11 through pipelines. The extension rod of the drive cylinder 10 is fixedly connected to the slide block 9. The multi-channel hydraulic station 11 drives the extension rod of the drive cylinder 10 to extend and retract, causing the slide block 9 to slide on the linear slide rail 8, thereby driving the oil constant temperature tank 1 to reciprocate linearly. The winding pressure cylinder 2, which moves with the oil constant temperature tank 1 to directly below the gantry press 5, is in the high-pressure densification processing state. The other two winding pressure cylinders 2 are in the heating and pressing state and the material loading and unloading state, respectively. After the powder is densified by the gantry press 5, the winding pressure cylinder 2 in the high-pressure densification state moves away from the gantry press 5 with the oil constant temperature tank 1. The winding pressure cylinder 2 in the heating and pressing state moves with the oil constant temperature tank 1 to directly below the gantry press 5. At this time, the winding pressure cylinder 2 in the high-pressure densification state immediately switches to the material loading and unloading state, the winding pressure cylinder 2 in the heating and pressing state immediately switches to the high-pressure densification state, and the winding pressure cylinder 2 in the material loading and unloading state immediately switches to the heating and pressing state. In this way, the working state of the three winding pressure cylinders 2 is rotated during the reciprocating movement of the oil constant temperature tank 1.

[0032] The cylinder diameter of the gantry press 5 is larger than the inner diameter of the pressure cylinder body. A sealing piston 6 is installed on the telescopic shaft of the gantry press 5, which is sealed to the winding pressure cylinder 2 to ensure that the internal pressure of the winding pressure cylinder 2 does not leak during the ultra-high pressure densification process. During the alternation of the working states of the three winding pressure cylinders 2, the gantry press 5 drives the sealed piston 6 to extend into the winding pressure cylinder 2 in the high-pressure densification state and press down. Under the pressure of the press, since the cylinder diameter of the press cylinder is larger than the inner diameter of the pressure cylinder body, the working area changes, thus forming an ultra-high pressure several times that of the press inside the pressure cylinder body of the winding pressure cylinder 2. Under the continuous pressure applied by the gantry press 5, the oil cannot be compressed due to its incompressibility, further generating ultra-high pressure inside the winding pressure cylinder 2, thereby uniformly pressing the powder in the flexible inner sleeve 3. After a certain period of high temperature and high pressure, the internal voids of the powder are compressed, thereby achieving a uniform densification effect. The winding pressure cylinder 2 in the heating and waiting-to-press state is heated and kept warm by the oil in the oil constant temperature pool 1, waiting for the subsequent densification process. The winding pressure cylinder 2 in the material loading and unloading state can take out the molding material inside and put in new powder, so that the powder can be preheated in the oil constant temperature pool 1 before the subsequent densification process.

[0033] During the pressurization process of the gantry press 5, the pressure increase follows the formula P=F / A; where P is the pressure in Pa; F is the applied force in N; and A is the contact area in m². Because the area of ​​the hydraulic system changes exponentially, the pressure applied to the winding pressure cylinder 2 can be calculated through force transmission and cylinder diameter ratio. After forming ultra-high pressure, the powder is uniformly stressed under high temperature and high pressure conditions, thereby achieving a highly efficient, uniform, and dense processing effect.

[0034] Traditional isostatic presses have heating devices inside the pressure cylinder, which results in lengthy preheating, heating, and cooling processes, low production efficiency, and inability to perform continuous production. Based on the aforementioned continuous high-temperature, ultra-high-pressure uniform densification treatment method for powders and its corresponding processing equipment, this invention uses an oil constant temperature pool 1 to seal and heat the winding pressure cylinder 2. That is, the working pressure cylinder is placed in a sealed and heated oil system to ensure that the working cylinder temperature remains stable throughout the production process, which is conducive to large-scale, continuous production and thus improves production efficiency while reducing costs and energy consumption.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for continuous high-temperature and ultra-high-pressure uniform densification of powder, characterized in that, include: Three winding pressure cylinders (2) are fixed in an oil constant temperature pool (1) containing oil, so that the three winding pressure cylinders (2) correspond to three working states: high pressure densification treatment, heating and waiting for pressure, and material handling. The powder to be pressed is loaded into the flexible inner sleeve (3) and sealed. Then the flexible inner sleeve (3) is placed into the sealing sleeve filled with constant temperature oil. Then the sealing sleeve is placed into the winding pressure cylinder (2). The oil in the constant temperature pool (1) is heated by the high temperature heating element (4) so ​​that the oil temperature rises to the set value and is kept constant. The hydraulic linear drive mechanism drives the oil constant temperature pool (1) to move back and forth in a linear motion, so that the working state of the three winding pressure cylinders (2) is rotated. During the rotation, the gantry press (5) drives the sealing piston (6) to pressurize the inside of the winding pressure cylinder (2) in the high pressure densification state, so that the powder is densified. The winding pressure cylinder (2) in the heating and waiting pressure state is heated and kept warm by oil in the oil constant temperature pool (1). The molding material in the winding pressure cylinder (2) in the material picking and placing state is taken out and new powder is put in.

2. The method for continuous high-temperature and ultra-high-pressure uniform densification of powder according to claim 1, characterized in that: The gantry press (5), hydraulic linear drive mechanism, and multi-channel hydraulic station (11) are all located on the base (7).

3. The method for continuous high-temperature and ultra-high-pressure uniform densification of powder according to claim 2, characterized in that: The hydraulic linear drive mechanism includes a linear slide rail (8), a slide block (9), and a drive cylinder (10). The linear slide rail (8) is located on the base (7) below the gantry press (5). The slide block (9) is slidably located on the linear slide rail (8). The oil constant temperature pool (1) is fixed on the slide block (9). The drive cylinder (10) is located on the base (7) on both sides of the linear slide rail (8). The extension rod of the drive cylinder (10) is connected to the slide block (9).

4. The method for continuous high-temperature and ultra-high-pressure uniform densification of powder according to claim 3, characterized in that: The base (7) is equipped with a multi-channel hydraulic station (11), and the gantry press (5) and the drive cylinder (10) are connected to the multi-channel hydraulic station (11) through oil circuits.

5. The method for continuous high-temperature and ultra-high-pressure uniform densification of powder according to claim 1, characterized in that: The heating element is placed in the oil constant temperature pool (1) and is arranged around the pressure cylinder (2).

6. The method for continuous high-temperature and ultra-high-pressure uniform densification of powder according to claim 1, characterized in that: The winding pressure cylinder (2) includes a pressure cylinder body and a steel strip. The pressure cylinder body is fixed inside the oil constant temperature pool (1), and the steel strip is wound around the outside of the pressure cylinder body.

7. The method for continuous high-temperature and ultra-high-pressure uniform densification of powder according to claim 6, characterized in that: The sealing sleeve includes an outer sleeve (12) and an outer sleeve cover (13). The outer sleeve (12) is filled with constant temperature oil. The outer sleeve (12) is located in the pressure cylinder body. The outer sleeve cover (13) is connected to the outer sleeve (12) by threads for sealing. The flexible inner sleeve (3) is placed inside the outer sleeve (12).

8. The method for continuous high-temperature and ultra-high-pressure uniform densification of powder according to claim 6, characterized in that: The cylinder diameter of the gantry press (5) is larger than the inner diameter of the pressure cylinder body.

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