A device and method for observing microscopic leaks in hydraulic seals

Abstract

This invention provides a microscopic leakage observation device for hydraulic seals, comprising: a housing (1), a base (2), a screw plug (3), an oil nozzle (4), a first oil passage (5), a seal (6), a second oil passage (9), a transparent sheet (10), and an optical amplifier; the seal (6) is located in a sealing groove at the bottom of the housing (1); the transparent sheet (10) is disposed in the base (2), located directly below the sealing groove at the bottom of the housing (1); a through hole is provided at the bottom of the base (2) as a microscopic leakage observation hole for the contact area between the seal (6) and the transparent sheet (10); the optical amplifier is used to magnify and display the microscopic structure of the contact area between the seal (6) and the transparent sheet (10) within the microscopic leakage observation hole. This invention can detect minute leaks occurring in the sealing structure.

Description

Technical Field

[0001] This invention pertains to hydraulic sealing technology, specifically relating to a device and method for observing microscopic leaks in hydraulic seals. Background Technology

[0002] Hydraulic sealing technology uses a sealing ring to contact and tightly fit a flat or cylindrical surface to prevent leakage of the hydraulic working medium within the internal space and external leakage, thus preventing the intrusion of external media or contaminants and ensuring the integrity of the hydraulic system's boundaries. Hydraulic mechanisms using high-pressure hydraulic oil as the working medium have advantages such as high power density, large output force, and simple control, and are used in the drive and control of equipment in engineering machinery, aerospace, and other fields. However, they also inevitably face the need for hydraulic medium sealing and leakage problems.

[0003] Modern sealing designs typically select an appropriate sealing pressure to achieve mutual compression and tight contact between the seal and the sealing surface, thereby blocking the path for oil leakage. It is generally believed that as long as the maximum contact pressure on the sealing surface is always greater than the oil pressure, the fluid leakage path can be blocked, and the sealing function can be achieved.

[0004] However, even seemingly smooth sealing surfaces of real parts actually possess microscopic roughness peaks. Therefore, even two surfaces in good contact can still exhibit leakage channels under higher-precision observation. To fundamentally understand the sealing mechanism and the causes of leakage, it is essential to study the sealing mechanism from a microscopic contact perspective. However, current research on hydraulic sealing mechanisms primarily relies on theoretical and simulation studies, lacking effective direct observation methods to observe and record the sealing contact state between the seal and the sealing surface, and to characterize the formation mechanism and patterns of leakage channels. Therefore, a device is needed to observe microscopic leakage in hydraulic seals, characterize the leakage formation mechanism, and detect minute leaks in sealing structures. Summary of the Invention

[0005] This invention provides a device and method for observing micro-leakage in hydraulic seals, which has the function of directly observing the contact state of the sealing interface and the micro-leakage process, characterizing the sealing leakage mechanism, and enabling the detection of micro-leakage in the sealing structure.

[0006] The first aspect of this invention provides a hydraulic seal micro-leakage observation device, comprising: a housing 1, a base 2, a screw plug 3, an oil nozzle 4, a first oil passage 5, a seal 6, a second oil passage 9, a transparent sheet 10, and an optical amplifier; wherein:

[0007] The housing 1 is located above the base 2, and the housing 1 and the base 2 are fastened together by bolts;

[0008] The top of the housing 1 has a first oil hole, and the screw plug 3 is installed at the first oil hole. The screw plug 3 is connected to the housing 1 by a threaded engagement.

[0009] The side of the housing 1 has a second oil hole, and the oil nozzle 4 is installed at the second oil hole on the side of the housing 1 and is fastened by bolts.

[0010] The bottom of the housing 1 has a sealing groove, and the seal 6 is located in the sealing groove at the bottom of the housing 1. The depth of the sealing groove is less than the thickness of the seal 6.

[0011] The first oil passage 5 is located inside the housing 1, connecting the first oil hole at the top of the housing 1 with the sealing groove at the bottom of the housing 1;

[0012] The second oil passage 9 is located inside the housing 1 and connects the second oil hole on the side of the housing 1 with the first oil passage 5.

[0013] Oil nozzle 4 is connected to an external oil source;

[0014] The transparent sheet 10 is disposed inside the base 2, located directly below the bottom sealing groove of the housing 1, and completely covers the bottom sealing groove of the housing 1;

[0015] The bottom of the base 2 is provided with a through hole, which serves as a microscopic leakage observation hole in the contact area between the seal 6 and the transparent sheet 10. The area of ​​the through hole is smaller than that of the transparent sheet 10 and larger than that of the sealing groove at the bottom of the housing 1.

[0016] An optical amplifier is used to magnify and display the microstructure of the contact area between the seal 6 and the transparent sheet 10 within the micro-leakage observation hole.

[0017] Optionally, the transparent sheet 10 is made of plexiglass.

[0018] Optionally, the diameter of the first oil passage 5 is smaller than the inner diameter of the seal 6.

[0019] Optionally, the through hole can be an enlarged hole structure.

[0020] Optionally, the nozzle 4 is provided with a sealing groove, and a first auxiliary seal is provided in the sealing groove. The first auxiliary seal is interference-fitted with the housing 1.

[0021] Optionally, a second auxiliary seal is provided between the screw plug 3 and the housing 1, and the second auxiliary seal is interference-fitted with the housing 1.

[0022] Optionally, the optical amplifier is a microscope.

[0023] A second aspect of the present invention provides a method for observing microscopic leaks in hydraulic seals, employing the apparatus described in any one of the first aspects, the method comprising:

[0024] During the test, a lower medium pressure was selected, and the observation optical path and related external instruments were adjusted so that the sealing element 6 and the sealing contact area 12 could be clearly observed through the observation optical path 11. The initial shape of the sealing element 6 was checked to confirm that there were no initial abnormalities.

[0025] By gradually increasing the medium pressure, the changes in the seal 6 and the sealing contact area 12 can be observed through the optical path 11. The pressure point can be selected for observation and recording as needed.

[0026] This invention provides a device and method for observing microscopic leaks in hydraulic seals. Using this device to observe the microstructure of hydraulic seals, direct observation images can visually characterize the structural morphology of the seal under different media pressure conditions, including deformation, extrusion, and damage, as well as the distribution of the sealing contact area. Further processing and analysis of the observed images can obtain the contact width of the sealing contact area, revealing the morphology and dynamic process of the microscopic leakage channels. Furthermore, by directly observing the minute gaps at the edge of the sealing contact area, this device can detect minute leaks in the sealing structure, serving as a rapid method for determining seal leaks. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a hydraulic seal micro-leakage observation device according to the present invention;

[0028] Figure 2 This is a cross-sectional view of the hydraulic seal micro-leakage observation device of the present invention;

[0029] Figure 3 This is a schematic diagram illustrating the implementation effect of the hydraulic seal micro-leakage observation device of the present invention;

[0030] Explanation of reference numerals in the attached figures:

[0031] Housing-1, base-2, screw plug-3, oil nozzle-4, first oil passage-5, seal-6, second auxiliary seal-7, first auxiliary seal-8, second oil passage-9, transparent sheet-10, observation light path-11, sealing contact area-12. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setups and methods set forth below, but covers any improvements, substitutions, and modifications to structures, methods, and devices without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description to avoid unnecessarily obscuring the invention.

[0034] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0036] like Figure 1-3 As shown, this invention provides a hydraulic seal micro-leakage observation device, comprising a housing 1, a base 2, a screw plug 3, an oil nozzle 4, a first oil passage 5, a seal 6, a second auxiliary seal 7, a first auxiliary seal 8, a second oil passage 9, a transparent sheet 10, an observation optical path 11, and a sealing contact area 12, wherein:

[0037] The housing 1 is located above the base 2, and the housing 1 and the base 2 are fastened together by bolts;

[0038] The top of housing 1 has an oil hole;

[0039] The screw plug 3 is installed in the oil hole at the top of the housing 1, and the screw plug 3 is connected to the housing 1 by a threaded connection.

[0040] The second auxiliary seal 7 is located between the screw plug 3 and the housing 1, and is interference-fitted with the housing 1;

[0041] The side of the housing 1 has an oil hole;

[0042] The grease nipple 4 is installed in the oil hole on the side of the housing 1 and is fastened by bolts.

[0043] The first auxiliary seal 8 is located in the sealing groove of the oil nozzle 4 and is interference-fitted with the housing 1;

[0044] The bottom of housing 1 has a sealing groove;

[0045] The transparent sheet 10 is located directly below the bottom sealing groove of the housing 1 and completely covers the bottom sealing groove of the housing 1;

[0046] Seal 6 is located in the sealing groove at the bottom of housing 1;

[0047] The seal 6 is interference-fitted with the transparent sheet 10;

[0048] The sealing contact area 12 is the sealing contact area formed by the sealing element 6 and the transparent sheet 10;

[0049] The transparent sheet 10 is located between the housing 1 and the base 2;

[0050] The base 2 has a through hole in the middle, the through hole range is smaller than the transparent sheet 10 and larger than the sealing groove at the bottom of the shell 1.

[0051] The observation light path 11 is located directly below the transparent sheet 10. The transparent sheet 10, the seal 6, and the sealing contact area 12 can be observed through the observation light path 11.

[0052] The first oil passage 5 is located inside the housing 1, connecting the oil hole at the top of the housing 1 with the sealing groove at the bottom of the housing 1;

[0053] The second oil passage 9 is located inside the housing 1 and connects the oil hole on the side of the housing 1 with the first oil passage 5.

[0054] Oil nozzle 4 is connected to an external oil source;

[0055] The transparent sheet 10 is made of PMMA (polymethyl methacrylate), but is not limited to PMMA. It can also be made of other materials with high strength and good optical transparency to ensure that it will not be damaged under pre-pressure and medium pressure and has good light transmittance.

[0056] The specific form of the observation optical path 11 is an optical microscope located directly below the device. It can also be used to change the observation method or enhance the resolution of microstructures by connecting other optical path structures.

[0057] In this hydraulic seal micro-leakage observation device, the screw plug 3 is installed at the top of the housing 1. The screw plug 3 has external threads, and the oil hole at the top of the housing 1 has internal threads. The second auxiliary seal 7 is installed at the root of the screw plug 3 threads. The screw plug 3 and the housing 1 are connected by threaded engagement. Tightening the screw plug 3 can cause the second auxiliary seal 7 to be pressurized, thereby sealing the oil hole at the top of the housing 1.

[0058] The oil nozzle 4 is installed on the side of the housing 1 and is fastened with bolts. The oil nozzle 4 has a sealing groove and is equipped with a first auxiliary seal 8. The first auxiliary seal 8 is interference-fitted with the housing 1 to achieve a sealed connection between the oil hole on the side of the housing 1 and the oil nozzle 4.

[0059] The bottom of the housing 1 has a sealing groove, and the seal 6 is installed in the sealing groove at the bottom of the housing 1. The transparent sheet 10 is pressed against the surface of the seal 6. The transparent sheet 10 is located between the housing 1 and the base 2. The housing 1 and the base 2 are fastened by bolts, so that the transparent sheet 10 is tightly attached to the bottom of the housing 1 and presses against the seal 6. The seal 6 and the transparent sheet 10 are interference-fitted to form a sealing contact area 12.

[0060] The base 2 has a through hole in the middle, the through hole being smaller than the transparent sheet 10, which ensures that the base plate 2 presses the transparent sheet 10 tightly. The through hole in the middle of the base 2 is larger than the sealing groove at the bottom of the housing 1. The transparent sheet 10 is optically transparent, and the observation light path 11 located below the base 2 can observe the transparent sheet 10, the sealing element 6, and the sealing contact area 12.

[0061] The first oil passage 5 and the second oil passage 9 are located inside the housing 1. The first oil passage 5 and the second oil passage 9 intersect and connect the oil hole at the top of the housing 1, the sealing groove at the bottom of the housing 1, the oil hole on the side of the housing 1, and the oil nozzle 4 installed on the side of the housing 1. The oil nozzle 4 is connected to an external oil source. The external hydraulic medium flows into the housing 1 through the oil nozzle 4 and into the sealing groove at the bottom of the housing 1 through the connecting oil passage.

[0062] After external hydraulic medium enters, due to sealing differences, air present in the internal oil passages of housing 1 will accumulate in the oil hole at the top of the housing. The oil hole at the top of housing 1 is sealed by a screw plug 3. Tightening or loosening the screw plug 3 can change the sealing state of the oil hole at the top of housing 1. By slightly turning the screw plug 3, the sealing performance can be reduced, allowing the air accumulated in the oil passages at the top of the housing to be discharged. After the air is discharged, the screw plug 3 can be tightened to restore the sealing state.

[0063] In the implementation of this device, before the test begins, oil filling and air venting should be performed. The oil nozzle 4 is connected to an external oil source, and the pressure of the external oil source is adjusted to about 0.02 MPa. External oil is filled into the device. The screw plug 3 is slightly loosened, and air and oil will flow out from the top of the housing 1. After the internal air is discharged, the screw plug 3 is tightened to restore the sealing state, thus realizing the air venting of the oil circuit.

[0064] During the test, a lower medium pressure is selected, and the observation optical path and related external instruments are adjusted so that the seal 6 and the sealing contact area 12 can be clearly observed through the observation optical path 11. The initial shape of the seal 6 is checked to confirm that there are no initial abnormalities. The medium pressure is gradually increased, and the changes in the seal 6 and the sealing contact area 12 are observed through the observation optical path 11. Pressure points can be selected for observation and recording as needed.

[0065] This device is used for microscopic observation of hydraulic seals. Through direct observation images, it can visually characterize the structural morphology of the seal under different media pressure conditions, including deformation, extrusion, and damage, as well as the distribution of the sealing contact area. Further processing and analysis of the observed images can yield the contact width of the sealing contact area, revealing the morphology and dynamic process of microscopic leakage channels. Furthermore, by directly observing the minute gaps at the edge of the sealing contact area, this device can detect minute leaks in the sealing structure, serving as a rapid method for identifying seal leaks.

[0066] When applied to an environmental test chamber, this device can also be used to observe the environmental response behavior of a sealing structure under different temperature and pressure conditions, as well as to evaluate the environmental adaptability of its sealing performance.

[0067] The above-described embodiments are merely preferred embodiments of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be included within the scope of protection of the present invention.

Claims

1. A device for observing microscopic leaks in hydraulic seals, characterized in that, include: The components include: housing (1), base (2), screw plug (3), grease nipple (4), first oil passage (5), seal (6), second oil passage (9), transparent sheet (10), and optical amplifier; wherein: The housing (1) is located above the base (2), and the housing (1) and the base (2) are fastened together by bolts; The top of the housing (1) has a first oil hole, and a screw plug (3) is installed at the first oil hole. The screw plug (3) is connected to the housing (1) by a threaded connection. The housing (1) has a second oil hole on its side, and the oil nozzle (4) is installed at the second oil hole on the side of the housing (1) and is fastened by bolts; The bottom of the housing (1) has a sealing groove, and the seal (6) is located in the sealing groove at the bottom of the housing (1). The depth of the sealing groove is less than the thickness of the seal (6). The first oil passage (5) is located inside the housing (1) and connects the first oil hole at the top of the housing (1) with the sealing groove at the bottom of the housing (1); The second oil passage (9) is located inside the housing (1) and connects the second oil hole on the side of the housing (1) with the first oil passage (5); The grease nipple (4) is connected to an external oil source; The transparent sheet (10) is set inside the base (2), directly below the bottom sealing groove of the housing (1), and completely covers the bottom sealing groove of the housing (1); The bottom of the base (2) is provided with a through hole, which serves as a microscopic leakage observation hole for the contact area between the seal (6) and the transparent sheet (10). The area of ​​the through hole is smaller than that of the transparent sheet (10) and larger than that of the sealing groove at the bottom of the shell (1). An optical amplifier is used to magnify and display the microstructure of the contact area between the seal (6) and the transparent sheet (10) inside the micro-leakage observation hole.

2. The hydraulic seal micro-leakage observation device according to claim 1, characterized in that, The transparent sheet (10) is made of plexiglass.

3. The hydraulic seal micro-leakage observation device according to claim 1, characterized in that, The diameter of the first oil passage (5) is smaller than the inner diameter of the seal (6).

4. The hydraulic seal micro-leakage observation device according to claim 1, characterized in that, The through hole has an enlarged hole structure.

5. The hydraulic seal micro-leakage observation device according to claim 1, characterized in that, The nozzle (4) is provided with a sealing groove, and a first auxiliary seal is provided in the sealing groove. The first auxiliary seal is interference-fitted with the housing (1).

6. The hydraulic seal micro-leakage observation device according to claim 1, characterized in that, A second auxiliary seal is provided between the screw plug (3) and the housing (1), and the second auxiliary seal is interference-fitted with the housing (1).

7. The hydraulic seal micro-leakage observation device according to claim 1, characterized in that, The optical amplifier is a microscope.

8. A method for observing microscopic leaks in hydraulic seals, characterized in that, The method, employing the apparatus as described in any one of claims 1-2, comprises: During the test, a lower medium pressure was selected, and the observation optical path and related external instruments were adjusted so that the seal (6) and the sealing contact area (12) could be clearly observed through the observation optical path. The initial shape of the seal (6) was checked to confirm that there were no initial abnormalities. By gradually increasing the medium pressure, the changes in the seal (6) and the sealing contact area (12) can be observed through the optical path. Pressure points can be selected for observation and recording as needed.

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