A mold rubber plug for isostatic pressing of tungsten, molybdenum and the like

Abstract

The utility model provides a kind of tungsten, molybdenum bar isobaric compaction forming mould rubber plug, specifically relates to powder metallurgy isobaric compaction forming technical field, to solve in isostatic shrinkage process, the radial shrinkage of end cap to hollow rubber sleeve in the part close to end cap is hindered, and the technical problem of affecting product size and quality.The utility model includes sleeve, which is matched with the inner diameter of the hollow rubber sleeve;The sleeve is sequentially composed of upper cylinder and lower cylinder from top to bottom, the inside of the upper cylinder is provided with a supporting mechanism, and the bottom end of the lower cylinder is closed by a plug;The sleeve and the plug are made of rubber material and integrally connected.The utility model can replace the upper end cap or the lower end cap for sealing, reduce the hindering effect on the hollow rubber sleeve close to the lower cylinder part during isostatic shrinkage, ensure the consistency of the compact size, and avoid affecting the product quality.

Description

Technical Field

[0001] This utility model relates to the field of powder metallurgy isostatic pressing technology, and more specifically, to a rubber stopper for isostatic pressing molds of tungsten and molybdenum rods. Background Technology

[0002] Tungsten and molybdenum rod blanks are often prepared using powder metallurgy. Tungsten and molybdenum powders are loaded into a forming mold, the open end of the mold is sealed, and the sealed mold is placed in an isostatic press with liquid as the medium for pressing and forming to obtain tungsten and molybdenum rod blanks. The tungsten and molybdenum rod blanks are then sintered at high temperature to obtain sintered tungsten and molybdenum rod blanks. The tungsten and molybdenum rod blanks are then rolled to obtain tungsten and molybdenum rod materials with higher density and more uniform structure, and then processed into various products as needed.

[0003] Existing forming molds for tungsten and molybdenum rods use hollow rubber sleeves, with upper and lower end caps sealed at both ends by wire binding. During the loading process, if... Figure 1 As shown, the upper and lower end caps need to be inserted into the hollow rubber sleeve and sealed and fixed by binding with external steel wire.

[0004] During isostatic radial shrinkage, the solid end cap shrinks less while the hollow sleeve shrinks more. This results in the end cap blocking the radial shrinkage of the portion of the hollow sleeve that mates with it, as well as the portion near the end cap. Consequently, the radial compressive force transmitted to the powder decreases, leading to lower density and uneven dimensions in this part of the powder, resulting in defects such as pressed "elephant legs," chipped edges, and missing corners. Figure 2 As shown in the figure, this affects product quality. Utility Model Content

[0005] The purpose of this utility model is to provide a rubber stopper for isostatic pressing molds of tungsten and molybdenum rods, which can replace the upper or lower end cap for sealing, greatly reducing the radial shrinkage resistance of the hollow rubber sleeve near the lower cylinder, making the radial pressure transmitted to the powder uniform, ensuring the density and dimensional uniformity of the pressed powder, effectively solving defects such as "elephant legs", edge breakage, and corner missing during the pressing process, and avoiding affecting product quality.

[0006] The embodiments of this utility model are achieved through the following technical solutions: A rubber stopper for isostatic pressing of tungsten and molybdenum rods includes a sleeve whose outer diameter matches the inner diameter of a hollow rubber sleeve; the thickness of the sleeve is 1.1-1.5 times the thickness of the hollow rubber sleeve; the sleeve is composed of an upper cylinder and a lower cylinder from top to bottom; the upper cylinder has an internal support mechanism; the length of the lower cylinder is greater than or equal to the inner diameter of the hollow rubber sleeve; the bottom end of the lower cylinder is sealed by a plug; both the sleeve and the plug are made of rubber and integrally molded.

[0007] In some embodiments, the support mechanism includes a plurality of metal support rings arranged vertically inside the upper cylinder, the metal support rings being sleeved around the inside of the upper cylinder.

[0008] In some embodiments, the diameter of the metal support ring is greater than or equal to the diameter of the binding wire; the distance between adjacent metal support rings is less than or equal to the diameter of the binding wire.

[0009] In some embodiments, an auxiliary support mechanism is fitted onto the inner side of the sleeve. The auxiliary support mechanism is made of rubber and is integrally formed and connected to the sleeve.

[0010] In some embodiments, the auxiliary support mechanism includes a fixed column coaxially arranged with the sleeve, the radius of the fixed column being 1.2-1.5 times the thickness of the support plate, and the bottom of the fixed column being fixedly connected to the top of the plug; a plurality of support plates are evenly distributed around the outside of the fixed column, one side of the support plate being fixedly connected to the fixed column, and the other side of the support plate being fixedly connected to the inner wall of the sleeve; the fixed column and the support plate are integrally formed and connected.

[0011] In some embodiments, the number of support plates is four, and the thickness of the support plates is 0.8-1.1 times the thickness of the hollow rubber sleeve.

[0012] In some embodiments, the bottom end of the plug is provided with an upwardly recessed groove.

[0013] The technical solution of this utility model embodiment has at least the following advantages and beneficial effects: 1. This device is used to replace existing end caps for sealing hollow rubber sleeves. During isostatic compression shrinkage, the hollow lower cylinder of this device will radially shrink along with the hollow rubber sleeve it matches, thereby greatly reducing the radial shrinkage resistance of the hollow rubber sleeve near the end cap, making the radial pressure transmitted to the powder uniform, ensuring the density and dimensional uniformity of the pressed powder, effectively solving defects such as "elephant legs," edge chipping, and corner missing during the pressing process, and avoiding affecting product quality. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram illustrating the connection between the upper and lower end caps and the hollow rubber sleeve in the prior art. Figure 2 This diagram illustrates the radial shrinkage process during the pressing of the upper and lower end caps in the prior art, as well as the defects generated by the pressing of the blank near the upper and lower end caps.

[0016] Figure 3 A perspective view of a rubber stopper for isostatic pressing of tungsten and molybdenum rods provided in an embodiment of this utility model; Figure 4 A front view of a rubber stopper for isostatic pressing of tungsten and molybdenum rods provided in an embodiment of this utility model; Figure 5 for Figure 3 Structural cross-sectional view of section A in the middle; Figure 6 This is a schematic diagram of the installation and fitting of a rubber plug and a hollow rubber sleeve in an isostatic pressing mold for tungsten and molybdenum rods, as provided in an embodiment of this utility model. Figure 7 A top view of a tungsten or molybdenum rod isostatic pressing mold plug provided in an embodiment of this utility model.

[0017] Icons: 1. Hollow rubber sleeve; 2. Upper cylinder; 3. Lower cylinder; 4. End cap; 5. Metal support ring; 6. Binding wire; 7. Fixing column; 8. Support plate; 9. Groove; 10. Steel sleeve; 11. End cap. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0020] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0021] In the description of this utility model, it should be noted that if terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" appear to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use, they are only for the convenience of describing this utility model 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 utility model.

[0022] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] Please see Figures 3-7 As shown, the main body of this embodiment is a tungsten and molybdenum rod isostatic pressing mold rubber stopper. The tungsten and molybdenum rod isostatic pressing mold rubber stopper includes a sleeve whose outer diameter matches the inner diameter of the hollow rubber sleeve 1. The thickness of the sleeve is 1.1-1.5 times the thickness of the hollow rubber sleeve. The sleeve is composed of an upper cylinder 2 and a lower cylinder 3 from top to bottom. The upper cylinder 2 is provided with a support mechanism inside. The length of the lower cylinder is greater than or equal to the inner diameter of the hollow rubber sleeve. The bottom end of the lower cylinder 3 is closed by a plug 4. The sleeve and the plug 4 are both made of rubber and integrally molded.

[0024] In some embodiments, the support mechanism includes a plurality of metal support rings 5 ​​arranged vertically inside the upper cylinder 2, the metal support rings 5 ​​being sleeved around the inside of the upper cylinder 2.

[0025] In some embodiments, the diameter of the metal support ring 5 is greater than or equal to the diameter of the binding wire 6; the distance between adjacent metal support rings 5 ​​is less than or equal to the diameter of the binding wire 6.

[0026] In some embodiments, an auxiliary support mechanism is fitted onto the inner side of the sleeve. The auxiliary support mechanism is made of rubber and is integrally formed and connected to the sleeve.

[0027] In some embodiments, the auxiliary support mechanism includes a fixed column 7 coaxially arranged with the sleeve, the radius of the fixed column being 1.2-1.5 times the thickness of the support plate, and the bottom of the fixed column 7 being fixedly connected to the top of the plug 4; four support plates 8 are evenly distributed around the outside of the fixed column 7, the thickness of the support plate being 0.8-1.1 times the thickness of the hollow rubber sleeve, one side of the support plate 8 being fixedly connected to the fixed column 7, and the other side of the support plate 8 being fixedly connected to the inner wall of the sleeve; the fixed column 7 and the support plate 8 are integrally formed and connected.

[0028] In some embodiments, the bottom end of the plug 4 is provided with an upwardly recessed groove 9.

[0029] In this process, the plug 4 of the lower cylinder 3 is inserted into the hollow rubber sleeve 1 from the end of the hollow rubber sleeve 1. Then, the worker applies a certain pressure to the ends of the fixing column 7 and the support plate 8 on the inner side of the sleeve to completely insert the rubber plug into the hollow rubber sleeve 1. The plug is then tied to the outside of the hollow rubber sleeve 1 with wire to seal the mating surface between the hollow rubber sleeve 1 and the upper cylinder 2 of the rubber plug. The sleeve is divided into two parts: an upper cylinder 2 and a lower cylinder 3. A metal support ring 5 is provided in the upper cylinder 2. Since the metal support ring 5 has high rigidity, it is difficult to deform during isostatic pressing. Therefore, after being combined with the hollow rubber sleeve and tied with iron wire 6, a reliable seal can be achieved to prevent leakage. The lower cylinder 3, the plug 4, the fixing column 7, and the support plate 8 are all integrally formed and made of the same rubber material as the hollow rubber sleeve 1. Therefore, they have a certain degree of elasticity and will shrink and deform along with the hollow rubber sleeve 1 during isostatic pressing. Even if the upper cylinder 2 will obstruct the hollow rubber sleeve to a certain extent, the deformation of the lower cylinder 3 can reduce or even eliminate its impact on the pressed blank and avoid affecting the product quality.

[0030] The multiple metal support rings 5 ​​arranged inside the upper cylinder 2 are equivalent to rigid end caps 11, which provide support for the sleeve. Secondly, since the support plate 8 and the plug 4 connected to the lower cylinder 3 are made of rubber and have a certain degree of elasticity, the lower cylinder 3 can undergo a certain deformation during the isostatic pressing of tungsten and molybdenum rods. This prevents the hollow rubber sleeve 3 from being blocked, allowing the radial pressure to be fully transmitted to the end of the blank, thereby reducing or even avoiding the formation of defects such as "elephant legs", edge chipping, and missing corners at the ends of tungsten and molybdenum rods to a certain extent.

[0031] In addition, the groove 9 at the bottom of the plug 4 makes the end of the tungsten and molybdenum rods have a certain arc shape, which is beneficial to the next rolling process of the tungsten and molybdenum rods.

[0032] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A rubber stopper for isostatic pressing of tungsten or molybdenum rods, characterized in that, Includes a sleeve whose outer diameter matches the inner diameter of the hollow rubber sleeve (1); the thickness of the sleeve is 1.1-1.5 times the thickness of the hollow rubber sleeve (1); the sleeve is composed of an upper cylinder (2) and a lower cylinder (3) from top to bottom; the upper cylinder (2) is provided with a support mechanism inside; the length of the lower cylinder (3) is greater than or equal to the inner diameter of the hollow rubber sleeve; the bottom end of the lower cylinder (3) is closed by a plug (4); the sleeve and the plug (4) are both made of rubber and are integrally molded and connected.

2. The isostatic pressing mold stopper for tungsten and molybdenum rods according to claim 1, characterized in that, The support mechanism includes a plurality of metal support rings (5) arranged vertically inside the upper cylinder (2), and the metal support rings (5) are sleeved around the inside of the upper cylinder (2).

3. The isostatic pressing mold stopper for tungsten and molybdenum rods according to claim 2, characterized in that, The diameter of the metal support ring (5) is greater than or equal to the diameter of the binding wire (6); the distance between adjacent metal support rings (5) is less than or equal to the diameter of the binding wire (6).

4. The isostatic pressing mold stopper for tungsten and molybdenum rods according to claim 1, characterized in that, An auxiliary support mechanism is fitted onto the inner side of the sleeve. The auxiliary support mechanism is made of rubber and is integrally formed and connected to the sleeve.

5. The isostatic pressing mold stopper for tungsten and molybdenum rods according to claim 4, characterized in that, The auxiliary support mechanism includes a fixed column (7) coaxially arranged with the sleeve. The radius of the fixed column (7) is 1.2-1.5 times the thickness of the support plate (8). The bottom of the fixed column (7) is fixedly connected to the top of the plug (4). Multiple support plates (8) are evenly distributed around the outside of the fixed column (7). One side of the support plate (8) is fixedly connected to the fixed column (7), and the other side of the support plate (8) is fixedly connected to the inner wall of the sleeve. The fixed column (7) and the support plate (8) are integrally formed and connected.

6. The isostatic pressing mold stopper for tungsten and molybdenum rods according to claim 5, characterized in that, The number of support plates (8) is four, and the thickness of the support plates (8) is 0.8-1.1 times the thickness of the hollow rubber sleeve (1).

7. The isostatic pressing mold stopper for tungsten and molybdenum rods according to claim 1, characterized in that, The bottom end of the plug (4) is provided with an upwardly recessed groove (9).

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