阅读说明：本技术 密封元件的加工方法、密封元件及真空泵 (Machining method of sealing element, sealing element and vacuum pump ) 是由 丁印明 雷晓宏 魏民 于 2020-06-18 设计创作，主要内容包括：本发明提供了一种密封元件的加工方法、密封元件及真空泵,其中,密封元件的加工方法,包括：在马氏体相变下,将合金件在圆柱销上进行缠绕,并将合金件的两端对接以形成环形支撑件；将环形支撑件和橡胶原料放置在模具中；去除密封元件毛坯的毛边；清洗去除毛边后的密封元件毛坯,得到清洗过的密封元件毛坯；清洗过的密封元件毛坯通过平板模压进行二次硫化成型得到密封元件中间件；对密封元件中间件进行冷却处理,以得到密封元件。本申请的技术方案有效地解决了相关技术中的O型圈在密封过程中,容易受到工作中气体的侵蚀而快速老化以及弹性降低导致密封性能降低的问题。(The invention provides a processing method of a sealing element, the sealing element and a vacuum pump, wherein the processing method of the sealing element comprises the following steps: under the martensite phase transformation, winding the alloy piece on a cylindrical pin, and butting two ends of the alloy piece to form an annular support piece; placing the annular support and rubber feedstock in a mold; removing burrs of the sealing element blank; cleaning the seal element blank after the burrs are removed to obtain a cleaned seal element blank; carrying out secondary vulcanization molding on the cleaned sealing element blank through flat plate die pressing to obtain a sealing element intermediate piece; and cooling the sealing element intermediate piece to obtain the sealing element. The technical scheme of this application has solved O type circle among the correlation technique effectively and in the sealing process, receives the erosion of gas in the work and rapid ageing and elasticity reduce the problem that leads to the sealing performance to reduce easily.)

1. A method of manufacturing a sealing element, comprising:

under the martensite phase transformation, winding an alloy piece on a cylindrical pin, and butting two ends of the alloy piece to form an annular support piece;

placing the annular support piece and the rubber raw material in a mold, and carrying out one-step vulcanization molding through flat plate mold pressing to obtain a sealing element blank, wherein the one-step vulcanization molding step meets the following requirements: the vulcanization temperature is within the range of 170-180 ℃, the vulcanization time is within the range of 5-20 min, and the vulcanization pressure is within the range of 10-20 Mpa;

removing burrs of the sealing element blank;

cleaning the rough edge-removed sealing element blank to obtain the cleaned sealing element blank;

carrying out secondary vulcanization forming on the cleaned sealing element blank through the flat plate die pressing to obtain a sealing element intermediate piece;

and cooling the sealing element intermediate piece to obtain the sealing element (10).

2. The method for processing a sealing member according to claim 1, wherein the secondary vulcanization molding step satisfies: the vulcanization temperature is within the range of 200-260 ℃, and the vulcanization time is within the range of 4-24 h.

3. The method of claim 1, wherein the cooling treatment of the sealing member intermediate member is performed for a time in a range of 1h to 1.5 h.

4. The method of manufacturing a sealing element according to claim 1, further comprising, after the step of obtaining the sealing element (10):

detecting whether the sealing element is qualified or not, wherein the qualified sealing element meets the following requirements: the seal element (10) has a Shore A hardness in the range of 75-80, and the seal element (10) has no adhesive shortage, drape, air bubbles, shrinkage, weld marks, air bubbles, stripes, warping, delamination and peeling in appearance.

5. The method of claim 1, wherein the step of forming the annular support from the alloy member comprises: within a transformation temperature range to transform the martensitic alloy piece into the austenitic annular support; in the step after forming the annular support, comprising: heat treating the annular support, wherein the heat treatment comprises a solution treatment at a temperature in the range of 650-850 ℃ and an aging treatment at a temperature in the range of 450-550 ℃.

6. A sealing element, characterized in that it is obtained according to the method of processing a sealing element according to any one of claims 1 to 5, the sealing element (10) being a sealing ring, the sealing element (10) comprising an annular support (11) and a sealing body (12) wrapped outside the annular support (11).

7. The sealing element according to claim 6, characterized in that the inner and outer surfaces of the annular support (11) are both curved surfaces.

8. Sealing element according to claim 6, characterized in that the material of the sealing body (12) is a fluoro-or perfluoro-or ethylene propylene diene rubber.

9. Sealing element according to claim 6, characterized in that the material of the annular support (11) is a Ni-Ti alloy or a Cu-based alloy or a Fe-based alloy or a TiPdNi alloy.

10. Vacuum pump comprising a pump body assembly, characterized in that the pump body assembly comprises a stator body (1), a cover body (3) covering the stator body (1), and a sealing element (10) located between the stator body (1) and the cover body (3), wherein a sealing groove (4) is provided on the stator body (1), the sealing element (10) is located in the sealing groove (4), and the sealing element is the sealing element according to any one of claims 6 to 9.

Technical Field

The invention relates to the field of vacuum sources, in particular to a machining method of a sealing element, the sealing element and a vacuum pump.

Background

The existing vacuum pump is necessary vacuum source equipment in the semi-conductor industry, the chemical industry and the medical and pharmaceutical industry. Due to the particularity of the use industry, the sealing requirements of the vacuum pump are very strict. O-rings are often used to seal the connection between the stator and the pump body of a vacuum pump.

However, in the sealing process of the O-shaped ring, the O-shaped ring is easily corroded by gas in work and is rapidly aged, so that the joint is leaked, and the service life of equipment is influenced.

Disclosure of Invention

The invention mainly aims to provide a processing method of a sealing element, the sealing element and a vacuum pump, so as to solve the problems that an O-shaped ring in the related art is easy to corrode in the sealing process and is rapidly aged due to corrosion of working gas, and the sealing performance is reduced due to the reduction of elasticity.

In order to achieve the above object, according to one aspect of the present invention, there is provided a method of processing a sealing member, including: under the martensite phase transformation, winding the alloy piece on a cylindrical pin, and butting two ends of the alloy piece to form an annular support piece; placing the annular supporting piece and the rubber raw material in a mould, carrying out one-step vulcanization forming through flat plate mould pressing to obtain a sealing element blank, wherein the one-step vulcanization forming step meets the following requirements: the vulcanization temperature is within the range of 170-180 ℃, the vulcanization time is within the range of 5-20 min, and the vulcanization pressure is within the range of 10-20 Mpa; removing burrs of the sealing element blank; cleaning the seal element blank after the burrs are removed to obtain a cleaned seal element blank; carrying out secondary vulcanization molding on the cleaned sealing element blank through flat plate die pressing to obtain a sealing element intermediate piece; and cooling the sealing element intermediate piece to obtain the sealing element.

Further, the secondary vulcanization molding step satisfies: the vulcanization temperature is within the range of 200-260 ℃, and the vulcanization time is within the range of 4-24 h.

Further, the time for cooling the sealing member intermediate member is in the range of 1h to 1.5 h.

Further, after the step of obtaining the sealing element, the method further comprises: whether the sealing element is qualified or not is detected, and the qualified sealing element meets the following requirements: the seal element has a Shore A hardness in the range of 75-80, and the seal element has an appearance free of starvation, drape, bubbles, shrinkage, weld marks, bubbles, streaks, warpage, delamination, and peeling.

Further, the step of forming the annular support from the alloy piece comprises: within the transformation temperature range to transform the martensitic alloy piece into an austenitic toroidal support; the step after forming the annular support comprises: and carrying out heat treatment on the annular support, wherein the heat treatment comprises solution treatment and aging treatment, the temperature of the solution treatment is in the range of 650-850 ℃, and the temperature of the aging treatment is in the range of 450-550 ℃.

According to another aspect of the present invention, there is provided a sealing element obtained by the above processing method of a sealing element, the sealing element being a sealing ring, the sealing element including an annular support and a sealing body wrapped around the annular support.

Further, the inner surface and the outer surface of the annular support are both arc-shaped surfaces.

Furthermore, the material of the sealing body is fluororubber, perfluororubber or ethylene propylene diene monomer.

Furthermore, the annular support is made of Ni-Ti alloy, Cu-based alloy, Fe-based alloy or TiPdNi alloy.

According to another aspect of the present invention, there is provided a vacuum pump, which includes a pump body assembly, the pump body assembly includes a stator main body, a cover body covering the stator main body, and a sealing element located between the stator main body and the cover body, the stator main body is provided with a sealing groove, the sealing element is located in the sealing groove, and the sealing element is the above-mentioned sealing element.

By applying the technical scheme of the invention, the processing method of the sealing element comprises the following steps: in the martensite state, winding the alloy piece on a cylindrical pin, and butting two ends of the alloy piece to form an annular support piece; placing the annular supporting piece and the rubber raw material in a mould, carrying out one-step vulcanization forming through flat plate mould pressing to obtain a sealing element blank, wherein the one-step vulcanization forming step meets the following requirements: the vulcanization temperature is within the range of 170-180 ℃, the vulcanization time is within the range of 5-20 min, and the vulcanization pressure is within the range of 10-20 Mpa; removing burrs of the sealing element blank; cleaning the seal element blank after the burrs are removed to obtain a cleaned seal element blank; carrying out secondary vulcanization molding on the cleaned sealing element blank through flat plate die pressing to obtain a sealing element intermediate piece; and cooling the sealing element intermediate piece to obtain the sealing element. Thus, the sealing element can effectively improve the hardness, oil resistance, temperature resistance, aging resistance and corrosion resistance of the sealing element by the processing method of the sealing element. The sealing element is arranged at the joint of the stator or the pump body of the vacuum pump, and the aging resistance and the corrosion resistance of the sealing element are improved, so that the sealing performance is improved, meanwhile, the corrosion of gas in work can be effectively resisted, and the rapid aging is avoided. Therefore, the technical scheme of the application effectively solves the problems that in the sealing process of the O-shaped ring in the related technology, the O-shaped ring is easily corroded by gas in work and is rapidly aged, and the sealing performance is reduced due to the reduction of elasticity.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 shows a schematic flow diagram of an embodiment of a method of processing a sealing element according to the invention;

FIG. 2 shows a perspective schematic view of an embodiment of a sealing element according to the invention;

FIG. 3 shows a cross-sectional schematic view of the sealing element of FIG. 2 in transverse cross-section;

FIG. 4 shows a schematic cross-sectional view of the sealing element of FIG. 2, cut longitudinally;

FIG. 5 shows a plot of transformation temperatures for different Ni mole fractions in the Ni-Ti alloy of the sealing element of FIG. 2; and

figure 6 shows a partial schematic view of an embodiment of a vacuum pump according to the invention.

Wherein the figures include the following reference numerals:

1. a stator body; 3. a cover body; 4. a sealing groove; 10. a sealing element; 11. an annular support member; 12. and sealing the body.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

As shown in fig. 1 and 2, the present application provides a method of manufacturing a sealing element. The processing method of the sealing element comprises the following steps: under the martensite phase transformation, winding the alloy piece on a cylindrical pin, and butting two ends of the alloy piece to form an annular support piece; placing the annular supporting piece and the rubber raw material in a mould, carrying out one-step vulcanization forming through flat plate mould pressing to obtain a sealing element blank, wherein the one-step vulcanization forming step meets the following requirements: the vulcanization temperature is within the range of 170-180 ℃, the vulcanization time is within the range of 5-20 min, and the vulcanization pressure is within the range of 10-20 Mpa; removing burrs of the sealing element blank; cleaning the seal element blank after the burrs are removed to obtain a cleaned seal element blank; carrying out secondary vulcanization molding on the cleaned sealing element blank through flat plate die pressing to obtain a sealing element intermediate piece; the sealing member intermediate member is subjected to a cooling process to obtain the sealing member 10.

By applying the technical scheme of the embodiment, the processing method of the sealing element comprises the following steps: winding the alloy piece on a cylindrical pin in a martensite state, and butting two ends of the alloy piece to form an annular support piece; placing the annular supporting piece and the rubber raw material in a mould, carrying out one-step vulcanization forming through flat plate mould pressing to obtain a sealing element blank, wherein the one-step vulcanization forming step meets the following requirements: the vulcanization temperature is within the range of 170-180 ℃, the vulcanization time is within the range of 5-20 min, and the vulcanization pressure is within the range of 10-20 Mpa; removing burrs of the sealing element blank; cleaning the seal element blank after the burrs are removed to obtain a cleaned seal element blank; carrying out secondary vulcanization molding on the cleaned sealing element blank through flat plate die pressing to obtain a sealing element intermediate piece; the sealing member intermediate member is subjected to a cooling process to obtain the sealing member 10. Thus, the sealing element can effectively improve the hardness, oil resistance, temperature resistance, aging resistance and corrosion resistance of the sealing element by the processing method of the sealing element. The sealing element is arranged at the joint of the stator or the pump body of the vacuum pump, and the aging resistance and the corrosion resistance of the sealing element are improved, so that the sealing performance is improved, meanwhile, the corrosion of gas in work can be effectively resisted, the rapid aging is avoided, and the service life is prolonged. Therefore, the technical scheme of the embodiment effectively solves the problems that the O-shaped ring in the related art is easily corroded by gas in work in the sealing process, the O-shaped ring is rapidly aged, and the sealing performance is reduced due to the reduction of elasticity.

The inventor finds that the vacuum pump is always in a high-temperature state in long-time work, so that the O-shaped ring made of rubber is influenced by high temperature and working gas, the rebound resilience of the O-shaped ring is reduced, and even permanent deformation occurs, and the sealing effect is reduced. In this embodiment, the sealing element contains an annular support member, which is made of memory alloy. The memory alloy is shaped and deformed outside the phase transition temperature range, and can recover the original macroscopic shape when reaching the phase transition temperature. The sealing element is extruded in the sealing process, so that the annular support part is prevented from changing in shape, the annular support part generates a restoring force according to the self stretching or shrinking stress curve, the restoring force provides a supporting force for the whole sealing element, the whole plastic deformation trend of the sealing element is reduced, the whole elasticity of the sealing element is kept in a good state, and the long-time sealing effect is achieved.

As shown in fig. 1 and 2, the secondary vulcanization molding step satisfies: the vulcanization temperature is within the range of 200-260 ℃, and the vulcanization time is within the range of 4-24 h. Thus, the sealing member 10 obtained by the sealing member processing method can also effectively improve the tensile strength, elongation at break, low temperature brittle temperature, and compression set of the sealing member.

As shown in fig. 1 and 2, the cooling process is performed on the sealing member intermediate member for a time ranging from 1h to 1.5 h. After the sealing element intermediate member is subjected to cooling treatment for a time in the range of 1h to 1.5h, the hardness of the sealing element intermediate member is greatly improved.

As shown in fig. 1, after the step of obtaining the sealing element 10, the method further includes: whether the sealing element is qualified or not is detected, and the qualified sealing element meets the following requirements: the seal element 10 has a shore a hardness in the range of 75-80, and the seal element 10 has an appearance free of starvation, flash, bubbles, shrinkage, weld marks, bubbles, streaks, warpage, delamination, and peeling. This further ensures the sealing performance of the sealing member 10.

As shown in fig. 1, the processing method of the sealing element further includes: the step of forming the annular support member from the alloy member comprises: within the transformation temperature range to transform the martensitic alloy piece into an austenitic toroidal support; the step after forming the annular support comprises: and carrying out heat treatment on the annular support, wherein the heat treatment comprises solution treatment and aging treatment, the temperature of the solution treatment is in the range of 650-850 ℃, and the temperature of the aging treatment is in the range of 450-550 ℃. Thus, the annular support satisfying the above conditions allows the seal element to have good recovery characteristics.

As shown in FIG. 1, the annular support 11 is made of Ni-Ti alloy, Cu-based alloy, Fe-based alloy or TiPdNi alloy. Thus, according to the specific transformation temperature, before the annular support and the rubber material are placed in the mold, the annular support 11 made of one of Ni — Ti alloy, Cu-based alloy, Fe-based alloy or TiPdNi alloy may be selected, so that the sealing member obtained by the sealing member processing method may be applied to various environments. For example, Ni — Ti alloys, specifically, Ni50.4ti49.6, Ni50.2ti49.8, and Ni50Ti50, respectively, wherein the phase transformation temperature curves at different Ni mole fractions are shown in fig. 5, it can be seen from fig. 5 that the normal transformation temperature and the reverse transformation temperature increase simultaneously with the decrease of the Ni mole fraction, and the key parameter comparison information in fig. 5 is as follows:

ms is the martensite phase transformation starting temperature in the cooling process;

mf is the temperature for finishing the martensite phase transformation in the cooling process;

③ As-is the reverse transformation starting temperature of martensite in the heating process;

af is the reverse transformation final temperature of the martensite in the heating process;

rs-the R phase transformation (pre-martensite) starting temperature in the cooling process;

rf-the final temperature of the R phase transformation (pre-martensite) during cooling.

The application also provides a sealing element, as shown in fig. 2 to 4, the sealing element of the embodiment is obtained by the processing method of the sealing element. The sealing element 10 is a sealing ring, and the sealing element 10 includes an annular support 11 and a sealing body 12 wrapped outside the annular support 11. The processing method of the sealing element can solve the problems that the O-shaped ring in the related art is easy to corrode in the sealing process and is rapidly aged due to corrosion of working gas, and the sealing performance is reduced due to the reduction of the elasticity.

As shown in fig. 4, both the inner surface and the outer surface of the annular support 11 are arc-shaped surfaces. In this way, the provision of the arc-shaped surface enables the annular support 11 to uniformly apply a force to the sealing body 12 while ensuring that the annular support itself has a sufficient supporting force, so that the sealing element 10 has a good sealing effect. Annular support member 11 can be changed the shape when normal atmospheric temperature state under annular support member 11's effect in the inside of sealing body 12, more is favorable to sealing element's installation, the phenomenon that the O type circle rebounded fast among the correlation technique can not appear.

As shown in fig. 2 to 4, the material of the sealing body 12 is fluororubber, perfluororubber, or epdm rubber. Because the material of sealing body 12 can select any one kind from fluororubber or perfluororubber or ethylene propylene diene monomer rubber for sealing element can be to different operating modes, choose the sealing body 12 with this operating mode assorted material for use, make sealing element can reach more reliable sealed effect.

Before the sealing member blank is obtained by the one-time vulcanization molding through the flat plate molding, the shrinkage rate of the material of the rubber raw material before the sealing member blank is considered, and the sealing member is used at a high temperature, so that the hardness of the rubber raw material is correspondingly improved, and the sealing performance of the sealing member obtained after cooling treatment is ensured. The following data should be referred to in selecting the material of the rubber raw material:

1) the shrinkage of the fluorine rubber (FKM) is in the range of 3.4-2.8%, and the Shore A hardness is in the range of 75-80;

2) the shrinkage of the perfluororubber (FFKM) is in the range of 3.4-2.8%, and the Shore A hardness is in the range of 75-80;

3) the shrinkage of Ethylene Propylene Diene Monomer (EPDM) is within the range of 2.0-1.8%, and the Shore A hardness is within the range of 75-80.

The present application further provides a vacuum pump, as shown in fig. 6, comprising a pump body assembly. The pump body assembly comprises a stator body 1, a cover body 3 covering the stator body 1 and a sealing element 10 located between the stator body 1 and the cover body 3, wherein a sealing groove 4 is formed in the stator body 1, and the sealing element 10 is located in the sealing groove 4. The sealing element can solve the problems that the O-shaped ring in the related art is easily corroded by gas in work and rapidly aged in the sealing process, and the sealing performance is reduced due to the reduction of the elasticity, and the vacuum pump comprising the sealing element has the same effect. After the sealing element is extruded and deformed by the two sides of the stator body 1 and the cover body 3, the sealing element can fill the sealing groove 4, and a good sealing effect is achieved.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.