An aero-graphite seal assembly o-ring failure simulation device and method

Abstract

The application discloses an aviation graphite sealing assembly O-shaped sealing ring failure simulation device and method, and particularly relates to a method for simulating working environment including oil medium, working pressure, working temperature, working time and part deformation, clamping the O-shaped sealing ring by using the same O-shaped sealing ring clamp as the part structure, putting into a container filled with the same oil medium as the working time, heating according to certain conditions until the O-shaped sealing ring fails, and deducing the possible failure reason of the O-shaped sealing ring, which is suitable for aviation equipment graphite sealing assembly maintenance and fault elimination. The technical method and device overcome the shortcomings that the pressure of the oil medium is not considered and only the single axial deformation of the O-shaped sealing ring is considered in the commonly used GB / T 1690-2010 test method, and can more accurately simulate the O-shaped sealing ring failure critical temperature.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of the critical temperature test method for the failure of the O-shaped sealing ring of an aviation graphite sealing assembly, and particularly relates to an aviation graphite sealing assembly O-shaped sealing ring failure simulation device and method. BACKGROUND

[0002] The aviation graphite sealing assembly is composed of a graphite ring, a sealing ring, a stop ring, a wave spring and an O-shaped sealing ring. When working, under the action of the oil pressure, the elastic force of the wave spring pushes the graphite ring to contact the end face of the support ring of the DC motor assembly to realize dynamic sealing, and the O-shaped sealing ring is used to prevent oil medium leakage. In recent years, the sealing failure of the graphite sealing assembly has occurred many times. After disassembling the assembly, it is found that the O-shaped sealing ring is adhered to the graphite ring, and the surface of the O-shaped sealing ring has a concave deformation and a dense pitting morphology formed after local high temperature through the body microscope. In order to exclude the failure, it is urgent to find out the influence of temperature on the failure of the O-shaped sealing ring. The usual method is to refer to GB / T 1690-2010 “Physical and Chemical Rubber or Thermoplastic Rubber Oil Resistance Test Method” for simulation. However, this method has the following shortcomings:

[0003] 1. The purpose of this test is mainly oil resistance rather than failure.

[0004] 2. The pressure of the oil medium is not considered.

[0005] 3. The fixture structure used only considers the axial deformation of the O-shaped sealing ring, and does not consider the radial deformation, so the simulated failure critical temperature is not real. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art, provide an aviation graphite sealing assembly O-shaped sealing ring failure simulation device and method, which can fully simulate the working environment, including oil medium, working pressure, working temperature, working time and part deformation, provide a special O-shaped sealing ring fixture with the same structure as the part, and adopt a method combining theoretical calculation and physical test to more accurately simulate the failure temperature of the O-shaped sealing ring.

[0007] The purpose of the present application is achieved by the following technical solutions: an aviation graphite sealing assembly O-shaped sealing ring failure simulation device, comprising an O-shaped sealing ring clamp; the O-shaped sealing ring clamp comprises an upper pressing plate, a lower pressing plate and a connecting piece; the upper pressing plate and the lower pressing plate are connected through the connecting piece; the upper pressing plate is provided with an annular protrusion; the lower pressing plate is provided with an annular groove; the positions of the protrusion and the annular groove correspond to each other; the O-shaped sealing ring is loaded into the annular groove; the height of the protrusion is determined by the calculated actual strain maximum value of the O-shaped sealing ring; the annular groove is communicated with an oil passing groove; the oil passing groove is used for allowing oil to enter the annular groove; in the aviation graphite sealing assembly O-shaped sealing ring failure simulation device, the height of the protrusion of the upper pressing plate is the deformation variable of the actual work of the O-shaped sealing ring calculated by ANSYS software, which ensures that the axial deformation and compression amount of the O-shaped sealing ring are consistent with the actual situation; the size and structure of the annular groove in the lower pressing plate are designed to be consistent with the structure of the O-shaped sealing ring in the graphite sealing assembly assembly, which ensures that the radial deformation and compression amount of the O-shaped sealing ring are consistent with the actual situation; the oil passing groove can allow the oil medium to enter the annular groove, so as to ensure that the working environment medium of the O-shaped sealing ring is consistent with the actual situation;

[0008] The connecting piece is a bolt and a nut; the upper pressing plate and the lower pressing plate are both provided with bolt holes; the bolt passes through the bolt holes on the upper pressing plate and the lower pressing plate and is fixed by the nut;

[0009] It also comprises a sealed container and a high-temperature test box; the sealed container is used for loading oil and the O-shaped sealing ring clamp; the high-temperature test box is used for placing the sealed container and performing heating test;

[0010] The sealed container comprises a cylindrical body, a cover, a sealing ring and a fixing piece; the cover is arranged on the top of the cylindrical body and is fixed by the fixing piece; the sealing ring is arranged between the cylindrical body and the cover; the fixing piece can adopt a screw, the cover is provided with a threaded hole corresponding to the screw, and the upper end edge of the cylindrical body is provided with a threaded bottom hole corresponding to the screw so as to install the screw.

[0011] The present application also provides an aviation graphite sealing assembly O-shaped sealing ring failure simulation method, which adopts the aviation graphite sealing assembly O-shaped sealing ring failure simulation device described above; comprising the following steps:

[0012] 1) load the O-shaped sealing ring into the annular groove of the lower pressing plate of the O-shaped sealing ring clamp, align the annular protrusion of the upper pressing plate with the annular groove, and connect the upper pressing plate and the lower pressing plate by the connecting piece; the height of the protrusion is determined by the calculated actual strain maximum value of the O-shaped sealing ring;

[0013] 2) load the O-shaped sealing ring clamp prepared in step 1) into the sealed container, pour the same oil as the working oil into the sealed container, immerse the O-shaped sealing ring clamp, load the sealing ring and the cover of the sealed container, and fix by the fixing piece;

[0014] 3) The O-ring allows the use of temperature as the lower limit, and the actual working environment temperature as the upper limit, according to the 5℃ temperature gradient grouping, heating for 12h, the sealed container in step 2) is put into the high temperature test box for heating;

[0015] 4) The sealed container after heating is cooled to room temperature, and the O-ring is checked until failure occurs to determine the O-ring failure critical temperature;

[0016] In step 1), the calculation method of the maximum actual strain of the O-ring is as follows: using UG software to construct a 2D physical model according to the drawing, importing ANSYS software for calculation, solving the maximum stress and strain distribution of the O-ring under the boundary conditions of the O-ring being extruded by the graphite ring and the sealing ring and the oil working pressure, so as to determine the maximum actual strain of the O-ring;

[0017] The specific operation of using UG software to construct a 2D physical model and importing ANSYS software for calculation is as follows: the 2D behavior is set to be axisymmetric, and a contact pair with friction is created between the graphite ring, the sealing ring and the O-ring; the materials of the O-ring, the graphite ring and the sealing ring are selected, and the working temperature is set; hexahedron is used for grid setting to generate node and unit entity grid; a statics calculation module is established to solve the prestress of the model after the O-ring is assembled into the component, and the calculated results are imported into a second statics calculation module to solve the maximum stress and strain distribution of the O-ring under the boundary conditions of the O-ring being extruded by the graphite ring and the sealing ring and the oil working pressure, so as to determine the maximum actual strain of the O-ring.

[0018] The present application has the following advantages:

[0019] 1) The aviation graphite sealing assembly O-ring failure simulation device and method provided by the present application can fully consider the influence of oil medium, working pressure, working temperature, working time and part deformation on the O-ring, and can calculate the deformation of the sealing ring by using ANSYS software, control the radial and axial deformation of the O-ring by using a clamp with the same structure as the part, put it into a container filled with the same oil medium as in working time, and heat it according to certain conditions until the O-ring fails, so that the critical temperature of the O-ring failure can be accurately tested.

[0020] 2, the convex height of the upper pressing plate in the aviation graphite sealing assembly O-shaped sealing ring failure simulation device provided by the application is the deformation amount of the O-shaped sealing ring in actual work calculated by ANSYS software, which ensures that the axial deformation and compression amount of the O-shaped sealing ring are consistent with the actual situation; the size and structure of the annular groove in the lower pressing plate are designed to be consistent with the structure of the O-shaped sealing ring in the graphite sealing assembly assembly, so as to ensure that the radial deformation and compression amount of the O-shaped sealing ring are consistent with the actual situation; the oil groove can allow the oil medium to enter the annular groove, so as to ensure that the working environment medium of the O-shaped sealing ring is consistent with the actual situation.

[0021] 3, compared with the existing GB / T 1690-2010 technology, the O-shaped sealing ring clamp special structure used in the application is consistent with the actual working condition of the O-shaped sealing ring, the deformation amount of the O-shaped sealing ring is analyzed and calculated by using ANSYS software, the simulation parameters can be created more comprehensively and accurately, so that the actual working condition can be simulated better, including oil medium, working pressure, working temperature, working time and part deformation, the shortcomings that the pressure of the oil medium is not considered and only the single axial deformation of the O-shaped sealing ring is considered in the GB / T 1690-2010 test method are overcome, and the O-shaped sealing ring failure critical temperature can be simulated more accurately. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a structure schematic diagram of the O-shaped sealing ring clamp.

[0023] Figure 2 It is a structure schematic diagram of the O-shaped sealing ring clamp from one perspective.

[0024] Figure 3 It is a structure schematic diagram of the O-shaped sealing ring clamp from another perspective.

[0025] Figure 4 It is a structure schematic diagram of the upper pressing plate.

[0026] Figure 5 It is a structure schematic diagram of the upper pressing plate from one perspective.

[0027] Figure 6 It is a structure schematic diagram of the upper pressing plate from another perspective.

[0028] Figure 7 It is an enlarged schematic diagram of part of the structure of the upper pressing plate.

[0029] Figure 8 It is a structure schematic diagram of the lower pressing plate.

[0030] Figure 9 It is a structure schematic diagram of the lower pressing plate from one perspective.

[0031] Figure 10 It is a structure schematic diagram of the lower pressing plate from another perspective.

[0032] Figure 11 Structure diagram of sealed container.

[0033] Figure 12 Decomposition appearance diagram of O-ring in Example 3.

[0034] In the figure: 1. O-ring clamp; 11. upper pressing plate; 12. lower pressing plate; 13. protrusion; 14. annular groove; 15. oil passage groove; 16. bolt; 17. nut; 2. sealed container; 21. cylindrical body; 22. cover; 23. sealing ring; 24. fixing piece; 3. O-ring. DETAILED DESCRIPTION

[0035] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0037] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0038] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0039] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly placed when the product of the present application is used, or the orientation or positional relationship commonly understood by those skilled in the art, and are only for the convenience of describing the present application and simplifying the description, and are not intended to indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" and the like are only used to distinguish description, and cannot be understood as indicating or implying relative importance.

[0040] In the description of this invention, 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 invention based on the specific circumstances.

[0041] Example 1: As Figures 1-11 As shown, an O-ring failure simulation device for an aerospace graphite sealing assembly includes an O-ring clamp 1; the O-ring clamp 1 includes an upper pressure plate 11, a lower pressure plate 12, and a connector; the upper pressure plate 11 and the lower pressure plate 12 are connected by the connector; the upper pressure plate 11 is provided with an annular protrusion 13; the lower pressure plate 12 is provided with an annular groove 14; the positions of the protrusion 13 and the annular groove 14 correspond to each other; the O-ring 3 is inserted into the annular groove 14; the height of the protrusion 13 is determined by the calculated maximum actual strain of the O-ring 3; the annular groove 14 is connected to an oil passage groove 15; the oil passage groove 15 is connected to an oil passage groove 15. The groove 15 is used to allow oil to enter the annular groove 14; in the failure simulation device of the O-ring 3 of the aviation graphite sealing assembly, the height of the protrusion 13 of the upper pressure plate 11 is the actual working deformation of the O-ring 3 calculated by ANSYS software, ensuring that the axial deformation and compression of the O-ring 3 are consistent with the actual deformation; the size and structure of the annular groove 14 in the lower pressure plate 12 are designed to be consistent with the structure of the O-ring 3 in the graphite sealing assembly, ensuring that the radial deformation and compression of the O-ring 3 are consistent with the actual deformation; the oil groove 15 allows the oil medium to enter the annular groove, ensuring that the working environment medium of the O-ring 3 is consistent with the actual working environment.

[0042] The connecting components are bolts 16 and nuts 17; bolt holes are provided on both the upper pressure plate 11 and the lower pressure plate 12; the bolts 16 pass through the bolt holes on the upper pressure plate 11 and the lower pressure plate 12 and are then fixed with nuts 17.

[0043] It also includes a sealed container 2 and a high-temperature test chamber; the sealed container 2 is used to fill with oil and O-ring clamp 1; the high-temperature test chamber is used to place the sealed container 2 and conduct a heating test;

[0044] The sealed container 2 includes a cylindrical body 21, a cover 22, a sealing ring 23, and a fixing member 24; the cover 22 is disposed on the top of the cylindrical body 21 and fixed by the fixing member 24; the sealing ring 23 is disposed between the cylindrical body 21 and the cover 22; the fixing member 24 can be a screw, and the cover 22 has a threaded hole corresponding to the screw, and the upper edge of the cylindrical body 21 has a threaded bottom hole corresponding to the screw for screw installation.

[0045] Embodiment 2: An aviation graphite sealing assembly O-ring failure simulation method, using the aviation graphite sealing assembly O-ring 3 failure simulation device of embodiment 1; comprising the following steps:

[0046] 1) Put the O-ring 3 into the annular groove 14 of the lower pressing plate 12 of the O-ring clamp 1, align the annular protrusion 13 of the upper pressing plate 11 with the annular groove 14, and connect the upper pressing plate 11 and the lower pressing plate 12 by using the connecting piece; the height of the protrusion 13 is determined by the calculated maximum actual strain of the O-ring 3;

[0047] 2) Put the O-ring clamp 1 prepared in step 1) into the sealing container 2, pour the same oil as the working oil, and immerse the O-ring clamp 1, put on the sealing ring 23 and the cover 22 of the sealing container 2, and fix with the fixing piece 24;

[0048] 3) With the allowable use temperature of the O-ring as the lower limit and the actual working environment temperature as the upper limit, heat for 12 hours according to a temperature gradient of 5℃, and put the sealing container prepared in step 2) into the high temperature test box for heating;

[0049] 4) Cool the sealing container 2 after heating to room temperature, disassemble and check the O-ring 3, until failure occurs, to determine the critical temperature of the O-ring 3 failure;

[0050] In step 1), the calculation method of the maximum actual strain of the O-ring 3 is as follows: using Unigraphics NX11.0 software to build a 2D physical model according to the drawing, importing the ANSYS software for calculation, solving the maximum stress and strain distribution of the O-ring 3 under the boundary conditions of the O-ring 3 being extruded by the graphite ring and the sealing ring and being subjected to the working pressure of the oil, so as to determine the maximum actual strain of the O-ring 3;

[0051] The specific operation of using Unigraphics NX11.0 software to build a 2D physical model and importing the ANSYS software for calculation is as follows: the 2D behavior is set to be axisymmetric, and a contact pair with friction is created between the graphite ring, the sealing ring and the O-ring 3; the materials of the O-ring 3, the graphite ring and the sealing ring are selected, and the working temperature is set; hexahedron is used for grid setting to generate node and unit entity grid; a statics calculation module is established to solve the prestress of the model after the O-ring 3 is installed in the assembly, and the calculated results are imported into a second statics calculation module to solve the maximum stress and strain distribution of the O-ring 3 under the boundary conditions of the O-ring 3 being extruded by the graphite ring and the sealing ring and being subjected to the working pressure of the oil, so as to determine the maximum actual strain of the O-ring 3. Embodiment 3

[0052] Take a certain aircraft accessory machine case graphite sealing assembly O-ring failure simulation as an example to further describe, O-ring 3 material FX-4, the allowable use temperature is not more than 200 DEG C, the actual working environment temperature is not more than 220 DEG C.

[0053] The embodiment adopts a kind of aviation graphite sealing assembly O-ring 3 failure simulation device, including as shown in Figures 1-3 O-ring clamp 1. Wherein the specific structure of the upper pressing plate 11 of O-ring clamp 1 is as shown in Figures 4-7 The height of the protrusion 13 of the upper pressing plate 11 is the actual working deformation variable of O-ring 3 calculated by ANSYS software, which ensures that the axial deformation and compression amount of O-ring 3 are consistent with actual values. The specific structure of the lower pressing plate 12 of O-ring clamp 1 is as shown in Figures 8-10 Wherein the size and structure of annular groove 14 are consistent with the structure of O-ring 3 in graphite sealing assembly assembly, to ensure that the radial deformation and compression amount of O-ring 3 are consistent with actual values;Oil groove 15 can allow oil medium to enter the ring groove, to ensure that the working environment medium of O-ring 3 is consistent with actual values. The sealing container 2 of aviation graphite sealing assembly O-ring 3 failure simulation device is as shown in Figure 11 .

[0054] The embodiment adopts the aviation graphite sealing assembly O-ring 3 failure simulation device described above to carry out failure simulation method, and specifically includes the following steps:

[0055] S1: using Unigraphics NX11.0 software, according to drawing to build 2D physical model, and import ANSYS 11 software, 2D behavior is set to axisymmetric, respectively in graphite ring, sealing ring and O-ring 3 create contact pair with friction. O-ring 3 material FX-4, density: 67g / cm, tensile strength is greater than 14.7MPa, graphite ring, sealing ring selects default material, temperature 200 DEG C. Hexahedron is used for mesh setting, to generate 4701 nodes and 1442 unit solid grid. Establish static calculation module, solve the prestress of model after O-ring 3 is loaded into assembly, and the calculated results are imported into the second static calculation module, to solve the maximum stress and strain distribution of O-ring 3 under the boundary conditions of being extruded by graphite ring, sealing ring and sliding oil working pressure. Determine the maximum axial strain of O-ring 3 0.5 mm.

[0056] S2: according to the actual maximum strain of O-ring 3 calculated in step S1, the height value of the protrusion 13 of the upper pressing plate 11 in O-ring clamp 1 is 0.5 mm.

[0057] S3: Use the O-ring clamp 1 with the height of 0.5mm of the protrusion 13 of the upper pressing plate 11, put one O-ring 3 into the annular groove 14 of the lower pressing plate 12, align the protrusion 13 of the upper pressing plate 11 with the annular groove 14 of the lower pressing plate 12, and connect them through the bolt hole of the upper pressing plate 11 and the lower pressing plate 12 by using the bolt 16 and the nut 17.

[0058] S4: Use the sealed container 2 as shown in the figure, put the O-ring clamp 1 in step S3 into the cylinder 21, pour the same working oil 50-1-4 into the cylinder 21 to submerge the O-ring clamp 1, put the O-ring 23 and the cover 22, and use three screws to pass through the corresponding bolt hole of the cover 22 and connect with the corresponding threaded hole of the cylinder 21. Figure 11

[0059] S5: Put the container in step S4 into the Chongqing Yinheli WG3002AF high-temperature test box, and heat it according to the temperature gradient of 5℃ (200℃, 205℃, 210℃, 215℃, 220℃) with 12 hours of heating time, with the lower limit of 200℃ and the upper limit of 220℃ of the allowable temperature of the O-ring 3.

[0060] S6: Cool the sealed container 2 after heating to room temperature, and disassemble and check the O-ring 3. If the O-ring 3 fails at 220℃ (as shown in the figure), it is determined that the critical temperature of the O-ring 3 is 220℃. Figure 12

[0061] Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can modify the technical solutions described in the foregoing embodiments, or make equivalent replacements to part of the technical features, and any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.​​

Claims

1. An aircraft graphite seal assembly O-ring failure simulation device, characterized by: The O-ring clamp comprises an upper pressing plate, a lower pressing plate and a connecting piece; the upper pressing plate and the lower pressing plate are connected through the connecting piece; the upper pressing plate is provided with an annular protrusion; the lower pressing plate is provided with an annular groove for mounting the O-ring, and the size and structure of the annular groove are consistent with the assembly structure of the O-ring in the aviation graphite sealing assembly; the positions of the protrusion and the annular groove correspond to each other; the O-ring is mounted in the annular groove; the height of the protrusion is determined according to the maximum actual strain of the O-ring calculated by the ANSYS software; the annular groove is communicated with an oil passage; the oil passage is used for allowing oil to enter the annular groove.

2. The aircraft graphite seal assembly O-ring failure simulation device of Claim 1, wherein: The connecting piece is a bolt and a nut; the upper pressing plate and the lower pressing plate are both provided with bolt holes; the bolt passes through the bolt holes of the upper pressing plate and the lower pressing plate and is fixed by the nut.

3. The aircraft graphite seal assembly O-ring failure simulation device of Claim 1, wherein: The device further comprises a sealed container and a high-temperature test box; the sealed container is used for containing oil and the O-ring clamp; the high-temperature test box is used for placing the sealed container and performing heating test.

4. The aircraft graphite seal assembly O-ring failure simulation device of Claim 3, wherein: The sealed container comprises a cylindrical body, a cover, a sealing ring and a fixing piece; the cover is arranged on the top of the cylindrical body and is fixed by the fixing piece; the sealing ring is arranged between the cylindrical body and the cover.

5. An aircraft graphite seal assembly O-ring failure simulation method, characterized by: The device for simulating the failure of the O-ring of the aviation graphite sealing assembly is used.

6. The method of claim 5, wherein, The device comprises the following steps: 1) mounting the O-ring in the annular groove of the lower pressing plate of the O-ring clamp, aligning the annular protrusion of the upper pressing plate with the annular groove, and connecting the upper pressing plate and the lower pressing plate by the connecting piece; the height of the protrusion is determined according to the maximum actual strain of the O-ring calculated by the ANSYS software; 2) mounting the O-ring clamp prepared in step 1) in the sealed container, pouring oil identical to the working oil into the sealed container, submerging the O-ring clamp, mounting the sealing ring and the cover of the sealed container, and fixing by the fixing piece; 3) heating for 12 hours at a temperature gradient of 5 DEG C, with the lower limit being the allowable use temperature of the O-ring and the upper limit being the actual working temperature, and placing the sealed container prepared in step 2) in the high-temperature test box for heating; 4) cooling the sealed container to room temperature after the heating is completed, disassembling and checking the O-ring, until failure occurs, to determine the critical temperature of the O-ring failure. In step 1), the calculation method of the maximum actual strain of the O-ring is as follows: using the Unigraphics NX11.0 software to construct a 2D physical model according to the drawing, importing the ANSYS software for calculation, solving the maximum stress and strain distribution of the O-ring under the boundary conditions of the O-ring being extruded by the graphite ring and the sealing ring and being subjected to the working pressure of the oil, and thus determining the maximum actual strain of the O-ring.

7. The method of claim 6, wherein, The specific operation of using the Unigraphics NX11.0 software to construct a 2D physical model and importing the ANSYS software for calculation is as follows:

8. The method of claim 7, wherein, ​ 2D behavior is set as axisymmetric, respectively, in the graphite ring, sealing ring and O-ring between the creation of frictional contact pairs; select O-ring, graphite ring, sealing ring material, set the working temperature; using hexahedron mesh setting, generate node and unit entity mesh; to establish a statics calculation module, solve the model in the O-ring after loading into the assembly prestress, and the calculated results into the second statics calculation module, solve the graphite ring, sealing ring extrusion and oil working pressure boundary conditions, the maximum stress and strain distribution of O-ring, determine the actual strain maximum value of O-ring.

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