A spherical counterbore-taper semi-static sealing structure and a sealing specific pressure solving method thereof

Abstract

The present application relates to mechanical seal safety technical field, especially a kind of spherical stop - cone face semi-static sealing structure, including shell, valve core sealing pair, valve seat sealing pair;The valve core sealing pair is located in the shell interior and does reciprocating motion under the constraint of the shell, the contact site of the valve core sealing pair with the valve seat sealing pair is equipped with conical groove, and there is included angle between the taper surface of the conical groove and the bottom surface of the valve core sealing pair;The contact site of the valve seat sealing pair with the valve core sealing pair is equipped with spherical stop, and the circular arc surface of the spherical stop is sealed by tangential cooperation with the valve core taper surface.The present application also provides a kind of sealing specific pressure solving method of spherical stop - cone face semi-static sealing structure, can effectively guarantee the sealing area consistency of spherical stop - cone face semi-static sealing structure, and its sealing specific pressure is designed and checked, solving is fast, can be applied to the design process of spring type valve part semi-static sealing structure.

Description

Technical Field

[0001] This invention relates to the field of mechanical seal safety technology, and in particular to a spherical stop-conical semi-static sealing structure and a method for calculating the sealing specific pressure. Background Technology

[0002] Spring-loaded valve components are widely used in military and civilian applications such as aerospace, gas pipelines, and automotive and marine industries due to their low cost, high reliability, and rapid response. They control the opening and closing of the valve through the reciprocating motion of the valve core sealing pair, thereby regulating pipeline pressure, flow rate, and flow direction, and protecting system safety. These valves typically feature a semi-static sealing structure with an R-shaped stop and a flat mating surface. Their sealing contact area is small, resulting in a large sealing specific pressure under the same spring load, effectively ensuring the valve's sealing performance.

[0003] However, in order to ensure the smooth operation of the valve core sealing pair, the valve guide structure is mostly clearance fit. The existence of guide clearance and the eccentricity of the spring can easily cause the valve core sealing pair to deflect. This results in uneven pressure distribution between the valve core sealing pair and the R-shaped stop after multiple actions, or even no contact in some areas. The sealing pair forms a leakage channel, which leads to the failure of the valve's semi-static seal.

[0004] Therefore, a new sealing structure and its sealing pressure calculation method need to be proposed to ensure the consistency of the contact area and surface indentation between the valve core sealing pair and the valve seat stop after multiple operations, thereby achieving reliable sealing of the spring valve. Summary of the Invention

[0005] This invention addresses the limitations and defects of existing technologies by proposing a method for calculating the sealing specific pressure of a spherical stop-conical semi-static sealing structure. This method combines the characteristics of the semi-static sealing structure of spring-loaded valves, considers the influence of guide clearance on the valve core position and the contact pressure of the sealing pair, and proposes a spherical stop-conical semi-static sealing structure. By utilizing the isotropic characteristics of the spherical stop and the guiding effect of the inclined conical surface, the consistency of the contact area between the valve core and the spherical stop and the surface indentation is ensured after multiple operations, thereby achieving reliable sealing of the spring-loaded valve. This invention also proposes a valve core cone surface with a certain inclination angle in a spherical stop-conical semi-static sealing structure, which can induce the spherical stop to reseat. Furthermore, the distance from each contact point between the spherical stop and the valve core cone surface to the center of the circle containing the spherical stop is equal, effectively ensuring the uniformity and consistency of the contact pressure in the sealing area. A method for solving the sealing specific pressure of the spherical stop-conical semi-static sealing structure is also proposed. This method can quickly solve for the contact width and equivalent sealing specific pressure of the spherical stop-conical semi-static sealing structure, thereby guiding the design of the semi-static sealing structure and the selection of its geometric parameters, effectively improving the service performance of this type of spring-loaded valve.

[0006] A method for calculating the sealing specific pressure based on the above-mentioned spherical stop-conical semi-static sealing structure includes:

[0007] Step S1: Design the geometric parameters of the spherical stop-conical semi-static sealing structure and the constraints of the geometric parameters;

[0008] Step S2: Based on the geometric parameters, calculate the contact width between the spherical stop and the valve core sealing pair in the spherical stop-conical semi-static sealing structure;

[0009] Step S21: Calculate the total length L and total load F of the contact area between the spherical stop and the valve core sealing pair in the spherical stop-conical semi-static sealing structure based on the geometric parameters;

[0010] Step S22: Perform a force analysis on the spherical stop, and calculate the normal load F on the contact area by combining the total length L of the contact area and the total load F. N and the unit length load f perpendicular to the contact area of ​​the spherical stop N ;

[0011] Step S23: Combine the unit length load f N Equivalent Young's modulus E of sealing structural materials * Calculate the Hertzian contact half-width b of the contact area;

[0012] Step S3: Based on the contact width, calculate and verify the sealing pressure of the spherical stop-conical semi-static sealing structure.

[0013] Further, step S1 includes:

[0014] The valve core cone surface is designed with an inclination angle of θ, a bottom diameter of D, and a height of H.

[0015] The valve seat sealing pair is designed with a nominal diameter of d, a radius of SR for the circle containing the spherical stop, and a center of O. The center O of the circle containing the spherical stop is located on the vertical axis of symmetry of the valve seat sealing pair. Furthermore, point O is set... i The radius of the radius is r, which is the center of the fillet at the top of the spherical stop, and the fillet is tangent to both the circle containing the spherical stop and the wall of the flow channel. i , i = 1, 2, 3..., the tangent angle is

[0016] Furthermore, to ensure that the contact area between the valve core sealing pair and the valve seat sealing pair remains unchanged during repeated reciprocating motions, while also satisfying the requirement of the existing flow diameter, the valve core sealing pair must satisfy the following conditions: the diameter D of the bottom surface of the conical surface > d, and the inclination angle θ of the valve core conical surface > 0. It must also ensure that the spherical stop is tangent to the valve core conical surface. Therefore, the spherical stop-conical semi-static sealing structure should meet the following constraints:

[0017]

[0018] That is, the geometric parameters of the spherical stop-conical semi-static seal structure should meet the following requirements:

[0019]

[0020] Further, step S21 includes:

[0021] Based on the set geometric parameters, and assuming the spherical stop is tangent to the valve core cone surface, the total length L of the contact area is:

[0022] L=2πSRsinθ (3)

[0023] The total load F of the spherical stop-conical semi-static sealing structure can be obtained by the following formula:

[0024] F = F T -F L =F0+kl-ΔPS (4)

[0025] In the formula, F T =F0+kl is the spring force on the valve core sealing pair, where F0 is the spring force on the spherical surface of the spherical stop when it mates with the bottom surface of the conical surface, and k is the spring stiffness coefficient. F represents the relative displacement of the spring. L =ΔPS is the resultant force of the fluid acting on the valve core sealing surface, ΔP is the sealing pressure difference, S=π(SRsinθ) 2 This represents the area of ​​the fluid acting on the valve core sealing surface.

[0026] Further, step S22 includes:

[0027] A force analysis of the spherical stop reveals the following:

[0028] F N ×cosθ+F f ×sinθ=F (5)

[0029] In the formula, F N F is the normal load perpendicular to the contact area of ​​the spherical stop. f =μF N The frictional force on the spherical stop is μ, where μ is the coefficient of friction.

[0030] The normal load F on the contact area N for:

[0031]

[0032] The normal load F on the contact area N And the total length L of the contact area, the unit length load f perpendicular to the spherical stop contact area is obtained by solving. N for:

[0033]

[0034] Further, step S23 includes:

[0035] The equivalent Young's modulus E of the sealing structure material is known. * It can be obtained from the following formula:

[0036]

[0037] Where E1 and E2 are the Young's modulus of the two sealing structure materials, and V1 and V2 are the Poisson's ratios of the two materials, respectively.

[0038] Then, using Hertzian contact theory, the Hertzian contact half-width b of the contact area of ​​the spherical stop-conical semi-static sealing structure is:

[0039]

[0040] Further, step S3 includes:

[0041] For a spherical stop-conical semi-static seal structure, the minimum sealing specific pressure q required to maintain the seal is... min It can be obtained from the following formula:

[0042]

[0043] In the formula, C and K are both dimensionless constants related to material properties;

[0044] The equivalent sealing pressure q of the spherical stop-conical semi-static sealing structure is:

[0045]

[0046] The sealing design is checked using the sealing pressure ratio method. The design equivalent sealing pressure must meet the following requirements:

[0047] q min ≤q≤[q] (12)

[0048] In the formula, [q] represents the allowable sealing pressure.

[0049] The present invention also provides a spherical stop-conical semi-static sealing structure, comprising:

[0050] Body, valve core sealing pair, valve seat sealing pair;

[0051] The valve core sealing pair is located inside the housing and reciprocates under the constraint of the housing. The valve core sealing pair has a conical groove at the contact part with the valve seat sealing pair. There is an angle between the conical surface of the conical groove and the bottom surface of the valve core sealing pair.

[0052] The contact area between the valve seat sealing pair and the valve core sealing pair is provided with a spherical stop, and the arc surface of the spherical stop achieves sealing by tangentially engaging with the conical surface of the valve core.

[0053] This invention utilizes the guiding effect of the valve core conical surface to induce the valve core sealing pair to reseat. Furthermore, given that the center of the spherical stop is equidistant from all contact points on the valve core conical surface, a spherical stop structure is introduced to ensure that even if the valve core sealing pair is eccentric, the contact area and the fluid load remain unchanged. This guarantees the uniformity of the sealing pair contact pressure and the consistency of the elastic-plastic deformation area after multiple reseats, fundamentally avoiding the influence of guide clearance on the opening and closing process and sealing performance of the spring-loaded valve.

[0054] Compared with the prior art, the beneficial effects of the present invention are:

[0055] 1. The present invention provides a spherical stop-conical semi-static sealing structure, which addresses the valve core sealing pair eccentricity problem caused by the guide clearance in the R-shaped stop-planar sealing structure. By using the guiding effect of the conical surface to induce the valve core to reseat, the spherical stop structure is introduced to ensure the consistency of the sealing pair contact pressure and elastic-plastic indentation after multiple reseats, thereby fundamentally avoiding the influence of the guide clearance on the valve core sealing pair operation process and valve sealing performance.

[0056] 2. This invention provides a method for solving the sealing pressure of a spherical stop-conical semi-static sealing structure. It analyzes the spherical stop-conical semi-static sealing structure and its contact characteristics, designs the geometric parameters of the spherical stop and valve core sealing pair, and solves for the contact width of the sealing pair by combining the valve sealing structure dimensions and material properties. By considering both the valve load and the sealing pair contact width, the equivalent sealing pressure of the spherical stop-conical semi-static sealing structure is calculated, and its sealing pressure is designed and verified. The method is rapid and can be applied to the design process of semi-static sealing structures for spring-loaded valve parts. Attached Figure Description

[0057] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0058] In the attached diagram:

[0059] Figure 1 This is an overall flowchart of the spherical stop-conical semi-static sealing structure and its sealing specific pressure calculation method according to the present invention;

[0060] Figure 2 This is a cross-sectional schematic diagram of a spherical stop-conical semi-static sealing structure according to the present invention;

[0061] Figure 3 This is a partial schematic diagram of the sealing pair of a spherical stop-conical semi-static sealing structure according to the present invention;

[0062] Figure 4 This is a schematic diagram of the spherical stop structure of the spherical stop-conical semi-static sealing structure of the present invention;

[0063] Figure 5 This is a schematic diagram of the cylindrical-planar structure contact area of ​​a spherical stop-conical semi-static sealing structure according to the present invention;

[0064] Figure 6 This invention relates to a spherical stop-conical semi-static sealing structure and its sealing pressure calculation method, which illustrates the variation of the equivalent sealing pressure and minimum sealing pressure with the radius SR of the spherical stop.

[0065] Figure 7 The curves showing the equivalent and minimum sealing specific pressures of a spherical stop-cone semi-static sealing structure and its sealing specific pressure calculation method as a function of the valve core cone inclination angle θ are presented in this invention.

[0066] Figure 8 The curves showing the equivalent and minimum sealing pressures of a spherical stop-conical semi-static sealing structure and its sealing pressure calculation method, as a function of the sealing pair pressure difference ΔP, are presented. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0068] Example 1

[0069] Please see Figure 1-8 This invention provides a method for calculating the sealing specific pressure of a spherical stop-conical semi-static sealing structure, including:

[0070] Step S1:

[0071] In practical implementation, the valve seat sealing pair diameter is set to d = 6 mm, the valve core cone surface inclination angle is θ = 30°, the radius of the circle containing the spherical stop is SR = 12 mm, the radius of the fillet at the top of the spherical stop is r = 0.5 mm, and the tangent angle between the fillet and the spherical surface is... Furthermore, the diameter of the bottom surface of the cone is D = 8 mm, and the height of the cone surface of the valve core sealing pair is H = 3 mm. Substituting the above structural parameters into equation (2), the range of geometric parameters of the spherical stop is determined as follows:

[0072]

[0073] As can be seen from the above formula, the valve core sealing pair and the valve seat sealing pair are tangent and will not interfere with each other, and the geometric parameters of the spherical stop meet the design requirements.

[0074] Step S2:

[0075] In specific implementation, as shown in the appendix Figure 5 As shown, under normal load F N Under the action of [the valve core], the spherical stop and the valve core cone surface are in close contact, and the seal is achieved through the extrusion elastic deformation of the non-metallic material. The contact range of the spherical stop-cone semi-static sealing structure is actually a rectangular area with a contact length of L and a width of 2b. Given that the spherical surface of the spherical stop is tangentially in contact with the valve core cone surface, the total length L of the contact area can be obtained by solving equation (3):

[0076] L = 2πSRsinθ = 37.7 mm

[0077] Given that the spring load on the spherical stop when it mates with the conical bottom surface is F0 = 100 N, the spring stiffness coefficient is k = 5000 N / m, and the sealing pressure difference is ΔP = 0.5 MPa, and also the relative displacement of the spring... The area S of the fluid acting on the valve core sealing surface can be obtained separately:

[0078]

[0079] S = π(SRsinθ) 2 =113.1mm 2

[0080] The total load F can then be obtained from equation (4):

[0081] F = F0 + kl - ΔPS = 49.22 N

[0082] In practical implementation, the friction coefficient μ is taken as 0.3, then the normal load F N It can be obtained from equation (6):

[0083]

[0084] The unit length load f perpendicular to the contact area of ​​the spherical stop can be obtained by solving equations (5)-(7). N :

[0085]

[0086] In practical implementation, given that the Young's moduli of the two sealing structural materials are E1 = 199 GPa and E2 = 0.447 GPa, and their Poisson's ratios are v1 = 0.3 GPa and v2 = 0.4 GPa, respectively, then the equivalent Young's modulus E of the sealing structural material is... * It can be obtained from equation (8):

[0087]

[0088] Then, the Hertzian contact half-width b of the contact area can be obtained by equation (9):

[0089]

[0090] Step S3:

[0091] In practical implementation, similar to the R-shaped planar sealing structure, the sealing performance of the spherical stop-conical semi-static sealing structure mainly depends on the annular contact area of ​​the sealing pair. Based on the normal load and contact width of the sealing pair contact area obtained from the above formula, the equivalent sealing specific pressure of the spherical stop-conical semi-static sealing structure is calculated, and the obtained valve sealing specific pressure is checked to determine whether it meets the service performance requirements of the spring-loaded valve. Similarly, the equivalent sealing specific pressure value obtained by the above method is less than the actual ultimate sealing specific pressure experienced by the valve sealing pair, so the calculated spring load is too large, which is beneficial to the semi-static sealing performance of the valve.

[0092] In practical implementation, for polytetrafluoroethylene propylene Fs-46 material, taking C=16 and K=0.9, the minimum sealing pressure q required to maintain the spherical stop-conical surface fit seal is then determined. min It can be obtained from equation (10):

[0093]

[0094] Furthermore, the equivalent sealing pressure q of the spherical stop-conical semi-static seal structure can be obtained by solving equation (11):

[0095]

[0096] The sealing design was checked using the sealing pressure ratio method, and the design equivalent sealing pressure satisfies equation (12):

[0097] q min =2.29MPa≤q=6.68MPa≤[q]=20MPa

[0098] In the formula, [q] is the allowable sealing pressure, which is 20-30 MPa for polytetrafluoroethylene propylene Fs-46 material.

[0099] Thus, the equivalent sealing pressure of the spherical stop-conical semi-static sealing structure was obtained. The design verification results show that the sealing structure has good sealing performance under the above structure and geometric parameters.

[0100] Example 2

[0101] To investigate the variation of the design equivalent sealing pressure q of the spherical stop-conical semi-static seal structure with parameters such as the radius SR of the spherical stop, the inclination angle θ of the valve core cone surface, and the sealing pressure difference ΔP, the sealing pressure was quickly solved and verified based on the above material properties.

[0102] With other parameters remaining constant, if the radius of the spherical stop of the valve seat sealing pair varies within the range of SR = [9mm, 16mm], then the sealing specific pressure can be calculated using the method shown in the attached figure. Figure 6 The diagram shows the variation of the equivalent sealing pressure and the minimum sealing pressure with the radius SR of the spherical stop. The design equivalent sealing pressure gradually decreases as the radius SR of the spherical stop increases, while the minimum sealing pressure gradually increases as the radius SR of the spherical stop increases. When the radius SR of the spherical stop exceeds 15.5 mm, the design equivalent sealing pressure does not meet the minimum sealing pressure, and the seal fails.

[0103] When the inclination angle of the valve core sealing cone surface varies within the range of θ = (20°, 45°), the variation law of the design equivalent sealing specific pressure and the minimum sealing specific pressure with the inclination angle θ of the valve core cone surface is shown in the appendix. Figure 7 As shown, the design equivalent sealing pressure gradually decreases as the tilt angle θ of the valve core cone increases, while the minimum sealing pressure gradually increases as the tilt angle θ of the valve core cone increases. When the tilt angle θ > 42.8°, the design equivalent sealing pressure does not meet the minimum sealing pressure, and the seal fails.

[0104] When the pressure difference between the inside and outside of the sealing structure varies within the range of ΔP = [0, 0.9 MPa], the variation of the design equivalent sealing specific pressure and the minimum sealing specific pressure with the pressure difference ΔP between the sealing pairs is shown in the attached figure. Figure 8 As shown, the design equivalent sealing pressure gradually decreases with the increase of the sealing pair pressure difference ΔP, while the minimum sealing pressure increases with the increase of the sealing pair pressure difference ΔP. When the sealing pair pressure difference ΔP > 0.75MPa, the design equivalent sealing pressure does not meet the minimum sealing pressure, and the seal fails.

[0105] In summary, this method effectively ensures the consistency of contact pressure and elastoplastic indentation between the valve core sealing pair and the valve seat sealing pair in the spherical stop-conical semi-static seal structure after multiple reseating. It fundamentally avoids the influence of guide clearance on the valve core sealing pair's operation and valve sealing performance. Furthermore, it can quickly and accurately solve the equivalent sealing specific pressure of the spherical stop-conical semi-static seal structure under given operating conditions, and determine the changing trend and relative relationship between the design sealing specific pressure and the minimum sealing specific pressure. This method can be applied to the optimization design of semi-static seal structures and has significant application value for improving the service and sealing performance of spring-loaded valves.

[0106] Example 3

[0107] Please see Figure 2-3 This embodiment provides a spherical stop-conical semi-static sealing structure, including:

[0108] Body, valve core sealing pair, valve seat sealing pair;

[0109] The valve core sealing pair is located inside the housing and reciprocates under the constraint of the housing. The contact part between the valve core sealing pair and the valve seat sealing pair is provided with a conical groove, and there is an angle between the conical surface of the conical groove and the bottom surface of the valve core sealing pair.

[0110] The contact area between the valve seat sealing pair and the valve core sealing pair is provided with a spherical stop, and the arc surface of the spherical stop achieves sealing by tangentially fitting with the conical surface of the valve core.

[0111] In practical implementation, the sealing pair of a spring-loaded valve mainly consists of a valve core sealing pair and a valve seat sealing pair. Furthermore, the valve body constrains the movement of the valve core sealing pair and affects the valve's semi-static sealing performance. Ideally, the valve core sealing pair reciprocates along an axis coinciding with the valve seat sealing pair. In a steady state, it is coaxially fitted with the valve seat sealing pair. During multiple operations, the contact area between the valve core sealing pair and the valve seat sealing pair remains unchanged, and the contact pressure distribution in the sealing area is uniform, resulting in excellent sealing performance of the valve sealing pair. Under extreme operating conditions, the valve core sealing pair deflects due to the influence of the guide clearance and spring eccentricity, causing the mating surface between the valve core sealing pair and the valve seat sealing pair to tilt along the axis of the valve core sealing pair. At this time, the contact area and contact points of the valve seat sealing pair change. However, since the valve seat sealing pair is a spherical stop, the distance from each point on the spherical surface to the center of the sphere is equal, and the valve core sealing pair is pressed against the valve seat sealing pair under the action of spring load. Therefore, the contact surface and elastic-plastic deformation area of ​​the valve core sealing pair remain unchanged and are always perpendicular to the axis of the valve core sealing pair. This makes the surface contact pressure distribution of the spherical stop-conical semi-static seal structure uniform, which can effectively ensure the service performance of the spherical stop-conical semi-static seal structure.

[0112] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for solving the sealing specific pressure of a spherical shoulder-taper semi-static seal structure, characterized in that, include: Step S1: Design the geometric parameters of the spherical stop-conical semi-static sealing structure and the constraints of the geometric parameters. The spherical stop-conical semi-static sealing structure includes a housing, a valve core sealing pair, and a valve seat sealing pair. Step S2: Based on the geometric parameters, calculate the contact width between the spherical stop and the valve core sealing pair in the spherical stop-conical semi-static sealing structure; Step S21: calculating the total length of the contact area between the spherical stop and the valve core sealing pair in the spherical stop-taper surface semi-static sealing structure in combination with the geometric parameters L and total load F ; Step S22: force analysis is performed on the spherical stopper, and the total length of the contact area is combined with the total load L and the normal load F of the contact area is solved and the unit length load perpendicular to the contact area of the spherical stopper is solved ; Step S23: Combine the unit length load Based on the material parameters of the sealing structure, the Hertzian contact half-width of the contact area is calculated. b ; Step S3: Combine the Hertzian contact half-width of the contact area b Solve and verify the sealing specific pressure of the spherical stop-conical semi-static seal structure; Step S1 includes: The valve core cone inclination angle is designed to be... The diameter of the base of the cone is D The height of the valve core cone surface is H ; The nominal diameter of the valve seat sealing pair is designed to be... d The radius of the circle containing the spherical stop is SR The center of the ball is O The center of the circle containing the spherical stop O Located on the vertical axis of symmetry of the valve seat sealing pair; in addition, a point is set. The radius of the radius is the center of the fillet at the top of the spherical stop, which is tangent to both the circle containing the spherical stop and the wall of the flow channel. , i =1, 2, 3..., the tangent angle is... ; To ensure that the contact area between the valve core sealing pair and the valve seat sealing pair remains unchanged during repeated reciprocating motions, while also satisfying the requirement of the passage diameter, the valve core sealing pair must meet the requirement of the diameter of the bottom surface of the conical surface. D > d The valve core cone surface inclination angle >0 ； Furthermore, it is necessary to ensure that the spherical stop is tangent to the conical surface of the valve core. Therefore, the spherical stop-conical semi-static sealing structure should meet the following constraints: That is, the geometric parameters of the spherical stop-conical semi-static seal structure should meet the following requirements: in, The inclination angle of the valve core cone surface. For chamfering, d The nominal diameter of the valve seat sealing pair. D The diameter of the base of the cone. H The height of the valve core cone surface. SR Let be the radius of the circle containing the spherical stop. r The radius of the fillet; Step S21 includes: Based on the set geometric parameters, and assuming the spherical stop is tangent to the valve core cone surface, the total length of the contact area is... L for: The total load of the spherical stop-conical semi-static sealing structure F It can be obtained from the following formula: In the formula, The spring force on the valve core sealing pair This refers to the spring force exerted by the spherical surface of the spherical stop on the bottom surface of the conical surface when they mate. k This is the spring stiffness coefficient. This represents the relative displacement of the spring. The resultant force of the fluid acting on the valve core sealing surface. To seal the pressure difference, Let be the area of ​​the fluid acting on the valve core sealing surface. The inclination angle of the valve core cone surface. SR Let be the radius of the circle containing the spherical stop. D The diameter of the base of the cone; Step S22 includes: A force analysis of the spherical stop reveals the following: In the formula, The normal load is perpendicular to the contact area of ​​the spherical stop. The frictional force acting on the spherical stop. The coefficient of friction, The inclination angle of the valve core cone surface; The normal load on the contact area for: Normal load on the contact area and the total length of the contact area L The unit length load perpendicular to the contact area of ​​the spherical stop is obtained by solving. for: In the formula, L The total length of the contact area. This refers to the spring force exerted by the spherical surface of the spherical stop on the bottom surface of the conical surface when they mate. k This is the spring stiffness coefficient. SR Let be the radius of the circle containing the spherical stop. To seal the pressure difference, D The diameter of the base of the cone; Step S23 includes: The equivalent Young's modulus of the sealing structure material is known. It can be obtained from the following formula: in, , These are the Young's moduli of the two sealing structure materials. , These are the Poisson's ratios of the two materials, respectively. The Hertzian contact half-width of the contact area of ​​the spherical stop-conical semi-static sealing structure is then obtained using Hertzian contact theory. b for: In the formula, The load per unit length of the spherical stop contact area. SR Let be the radius of the circle containing the spherical stop. Equivalent Young's modulus of the sealing structure material; Step S3 includes: For a spherical stop-conical semi-static seal structure, the minimum sealing pressure required to maintain the seal is... It can be obtained from the following formula: In the formula, C, K All of these are dimensionless constants related to material properties. To seal the pressure difference, b For Hertzian contact half-width; The equivalent sealing pressure of the spherical stop-conical semi-static sealing structure is then... for: In the formula, The normal load is perpendicular to the contact area of ​​the spherical stop. L The total length of the contact area. b For Hertzian contact half-width; The sealing design is checked using the sealing pressure method, and the design equivalent sealing pressure must meet the following requirements: In the formula, The allowable sealing pressure.

2. A spherical stop-conical semi-static sealing structure for implementing the sealing specific pressure calculation method of the spherical stop-conical semi-static sealing structure as described in claim 1, characterized in that, include: Body, valve core sealing pair, valve seat sealing pair; The valve core sealing pair is located inside the housing and reciprocates under the constraint of the housing. The valve core sealing pair has a conical groove at the contact part with the valve seat sealing pair. There is an angle between the conical surface of the conical groove and the bottom surface of the valve core sealing pair. The contact area between the valve seat sealing pair and the valve core sealing pair is provided with a spherical stop, and the arc surface of the spherical stop achieves sealing by tangentially engaging with the conical surface of the valve core.

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