A method for quantitatively evaluating sealing performance of a pipe joint under lateral displacement

Abstract

This application belongs to the field of pipeline systems, and specifically relates to a method for quantitatively evaluating the sealing performance of pipe joints under lateral displacement. The method includes: constructing a rough surface micro-contact model at the micro level and calculating the critical contact pressure of the pipe joint; constructing a finite element model of the pipe joint at the macro level, applying a lateral displacement load perpendicular to the pipeline axial direction, and obtaining a nominal contact pressure distribution curve; calculating the region integral formed by the nominal contact pressure distribution curve and the critical contact pressure to obtain a quantitative evaluation index for evaluating the sealing performance of the pipe joint. This application considers the influence of pipe joint vibration conditions on sealing performance at both the micro and macro scales, achieving a quantitative evaluation of the sealing performance of pipe joints under lateral displacement.

Description

Technical Field

[0001] This application belongs to the field of pipeline systems, and specifically relates to a method for quantitatively evaluating the sealing performance of pipe joints under lateral displacement. Background Technology

[0002] In various engineering fields such as aerospace, special vehicles, marine vessels, and oil and gas, pipeline systems are ubiquitous in their power, braking, cooling, and lubrication systems. They are indispensable and crucial components in these engineering fields, ensuring the normal operation of these mechanical systems. Pipeline leaks can lead to significant economic losses, environmental pollution, and even endanger lives. Therefore, the sealing of pipeline systems is a critical engineering issue. To reduce sealing failures, it is necessary to analyze and evaluate the sealing performance of pipe joints, identify potential causes of sealing failure, and optimize the joint design. Analyzing and evaluating sealing performance first requires establishing quantitative evaluation indicators for sealing performance.

[0003] Currently, most methods for evaluating the sealing performance of sealing structures only establish and solve finite element static models of the sealing structure at a macroscopic scale. They quantitatively compare the relative advantages and disadvantages of sealing performance under different structures or conditions by analyzing and comparing the contact pressure and contact area at the sealing interface. However, they cannot make a quantitative judgment on the sealing performance of a specific structure or condition.

[0004] Therefore, there is an urgent need for a technical solution to overcome or mitigate at least one of the aforementioned defects in the existing technology. Summary of the Invention

[0005] The purpose of this application is to provide a quantitative evaluation method for the sealing performance of pipe joints under lateral displacement, so as to solve at least one problem existing in the prior art.

[0006] The technical solution of this application is:

[0007] The first aspect of this application provides a method for quantitatively evaluating the sealing performance of a pipe joint under lateral displacement, including:

[0008] A microscopic contact model of a rough surface is constructed at the microscopic level to calculate the critical contact pressure of the pipe joint;

[0009] A finite element model of the pipe joint is constructed at the macroscopic level, and a lateral displacement load is applied in the direction perpendicular to the pipe axis to obtain the nominal contact pressure distribution curve.

[0010] Calculate the integral of the region formed by the nominal contact pressure distribution curve and the critical contact pressure to obtain a quantitative evaluation index for evaluating the sealing performance of the pipe joint.

[0011] In at least one embodiment of this application, a micro-contact model of a rough surface is constructed based on surface roughness information, and the variation of the contact area between rough surfaces with normal pressure is analyzed.

[0012] In at least one embodiment of this application, the critical contact pressure is:

[0013] ;

[0014] Among them, P c Where F is the critical contact pressure, F is the normal pressure, and A is the contact area.

[0015] In at least one embodiment of this application, a finite element model of the pipe joint is constructed based on the pipe joint size information, and the curve of nominal contact pressure versus sealing contact bandwidth under a preset preload is analyzed.

[0016] In at least one embodiment of this application, the quantitative evaluation index is:

[0017] ;

[0018] Where S is a quantitative evaluation index, The nominal contact pressure distribution curve is shown, where x1 is the lower limit of the sealing contact bandwidth of the integral region, and x2 is the upper limit of the sealing contact bandwidth of the integral region.

[0019] The second aspect of this application provides a quantitative evaluation system for the sealing performance of pipe joints under lateral displacement, comprising:

[0020] The microscopic calculation module is used to construct a microscopic contact model of a rough surface at the microscopic level and calculate the critical contact pressure of the pipe joint.

[0021] The macroscopic calculation module is used to construct a finite element model of the pipe joint at the macroscopic level, apply a lateral displacement load in the direction perpendicular to the pipe axis, and obtain the nominal contact pressure distribution curve.

[0022] The evaluation index calculation module is used to calculate the regional integral formed by the nominal contact pressure distribution curve and the critical contact pressure to obtain a quantitative evaluation index for evaluating the sealing performance of the pipe joint.

[0023] In at least one embodiment of this application, the micro-computation module constructs a micro-contact model of a rough surface based on surface roughness information and analyzes the variation of the contact area between rough surfaces with normal pressure.

[0024] In at least one embodiment of this application, in the microcomputing module, the critical contact pressure is:

[0025] ;

[0026] Among them, P c Where F is the critical contact pressure, F is the normal pressure, and A is the contact area.

[0027] In at least one embodiment of this application, the macroscopic calculation module constructs a finite element model of the pipe joint based on the pipe joint size information and analyzes the curve of nominal contact pressure versus sealing contact bandwidth under a preset preload.

[0028] In at least one embodiment of this application, the quantitative evaluation index in the evaluation index calculation module is:

[0029] ;

[0030] Where S is a quantitative evaluation index, The nominal contact pressure distribution curve is shown, where x1 is the lower limit of the sealing contact bandwidth of the integral region, and x2 is the upper limit of the sealing contact bandwidth of the integral region.

[0031] The invention has at least the following beneficial technical effects:

[0032] The quantitative evaluation method for the sealing performance of pipe joints under lateral displacement proposed in this application considers the influence of the vibration conditions of the pipe joints on the sealing performance from both micro and macro scales, thus realizing the quantitative evaluation of the sealing performance of pipe joints under lateral displacement. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of quantitative evaluation indicators for one embodiment of this application. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0035] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this application.

[0036] The following is in conjunction with the appendix Figure 1 This application will be described in further detail.

[0037] The first aspect of this application provides a method for quantitatively evaluating the sealing performance of a pipe joint under lateral displacement, comprising the following steps:

[0038] A microscopic contact model of a rough surface is constructed at the microscopic level to calculate the critical contact pressure of the pipe joint;

[0039] A finite element model of the pipe joint is constructed at the macroscopic level, and a lateral displacement load is applied in the direction perpendicular to the pipe axis to obtain the nominal contact pressure distribution curve.

[0040] The integral of the region formed by the nominal contact pressure distribution curve and the critical contact pressure is calculated to obtain a quantitative evaluation index for evaluating the sealing performance of the pipe joint.

[0041] The present application discloses a quantitative evaluation method for the sealing performance of pipe joints under lateral displacement. First, the critical contact pressure for sealing the pipe joint is determined based on its microscopic dimensions. Then, a microscopic contact model of the rough surface is constructed based on given surface roughness information. The variation of the contact area between the rough surfaces with normal pressure is analyzed, and the critical contact pressure ensuring the sealing of the pipe joint is obtained.

[0042] The formula for calculating the critical contact pressure is:

[0043] ;

[0044] Among them, P c Where F is the critical contact pressure, F is the normal pressure, and A is the contact area.

[0045] This application presents a quantitative evaluation method for the sealing performance of pipe joints under lateral displacement. Secondly, it determines the sealing contact bandwidth and contact pressure of the sealing area based on macroscopic dimensions. A finite element model of the pipe joint is constructed based on the given basic design dimensions, and the distribution of nominal contact pressure with sealing contact bandwidth under a preset preload is analyzed.

[0046] This application presents a method for quantitatively evaluating the sealing performance of pipe joints under lateral displacement. Finally, a quantitative evaluation index is obtained through integral calculation. An effective seal can only be formed when the nominal contact pressure on the sealing surface is greater than the critical contact pressure. The integral of the region formed by the nominal contact pressure distribution curve and the critical contact pressure is used as the quantitative evaluation index for evaluating the sealing performance of the pipe joint.

[0047] The formula for calculating the quantitative evaluation index is:

[0048] ;

[0049] Where S is a quantitative evaluation index, The nominal contact pressure distribution curve is shown, where x1 is the lower limit of the sealing contact bandwidth of the integral region, and x2 is the upper limit of the sealing contact bandwidth of the integral region.

[0050] The larger the quantitative evaluation index S of sealing performance, the better the sealing performance.

[0051] The quantitative evaluation method for the sealing performance of pipe joints under lateral displacement in this application considers the influence of vibration conditions on the seal. A lateral displacement load is applied in the direction perpendicular to the pipeline axial direction to simulate the bending moment effect borne by the pipe joint under vibration conditions. The local contact pressure in the sealing area decreases as the bending moment increases, and the seal fails when it drops below the critical contact pressure.

[0052] The quantitative evaluation method for the sealing performance of pipe joints under lateral displacement in this application determines the critical contact pressure that ensures the sealing of the pipe joint by observing the variation of the contact area between micro-rough surfaces with normal pressure; it determines the contact pressure and contact area on the sealing interface through static analysis of the pipe joint; it uses the integral of the region formed by the nominal contact pressure distribution curve and the critical contact pressure as the quantitative evaluation index of the sealing performance of the pipe joint; and it simulates the bending moment effect of the pipe joint under vibration by applying a lateral displacement load in the direction perpendicular to the pipeline axial direction, and analyzes the influence of vibration on the sealing performance of the pipe joint by observing the non-uniformity of the circumferential stress distribution caused by the lateral displacement.

[0053] The quantitative evaluation method for pipe joint sealing performance under lateral displacement proposed in this application can comprehensively consider the macroscopic and microscopic scales of pipe joint sealing, and simultaneously take into account the influence of pipe joint vibration conditions on pipe joint sealing performance, thus meeting the requirements for quantitative evaluation of pipeline sealing performance.

[0054] The second aspect of this application provides a quantitative evaluation system for the sealing performance of pipe joints under lateral displacement, comprising:

[0055] The microscopic calculation module is used to construct a microscopic contact model of a rough surface at the microscopic level and calculate the critical contact pressure of the pipe joint.

[0056] The macroscopic calculation module is used to construct a finite element model of the pipe joint at the macroscopic level, apply a lateral displacement load in the direction perpendicular to the pipe axis, and obtain the nominal contact pressure distribution curve.

[0057] The evaluation index calculation module is used to calculate the regional integral formed by the nominal contact pressure distribution curve and the critical contact pressure to obtain a quantitative evaluation index for evaluating the sealing performance of the pipe joint.

[0058] The design details of each functional module of the quantitative evaluation system for pipe joint sealing performance under lateral displacement described in this application are the same as those of the quantitative evaluation method for pipe joint sealing performance under lateral displacement described above, and will not be repeated here.

[0059] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for quantitatively evaluating the sealing performance of pipe joints under lateral displacement, characterized in that, include: A microscopic contact model of a rough surface is constructed at the microscopic level to calculate the critical contact pressure of the pipe joint; A finite element model of the pipe joint is constructed at the macroscopic level, and a lateral displacement load is applied in the direction perpendicular to the pipe axis to obtain the nominal contact pressure distribution curve. Calculate the integral of the region formed by the nominal contact pressure distribution curve and the critical contact pressure to obtain a quantitative evaluation index for evaluating the sealing performance of the pipe joint.

2. The method for quantitatively evaluating the sealing performance of pipe joints under lateral displacement according to claim 1, characterized in that, A microscopic contact model of a rough surface is constructed based on surface roughness information, and the variation of the contact area between rough surfaces with normal pressure is analyzed.

3. The method for quantitatively evaluating the sealing performance of pipe joints under lateral displacement according to claim 2, characterized in that, The critical contact pressure is: ； Among them, P c Where F is the critical contact pressure, F is the normal pressure, and A is the contact area.

4. The method for quantitatively evaluating the sealing performance of pipe joints under lateral displacement according to claim 3, characterized in that, A finite element model of the pipe joint is constructed based on the pipe joint size information, and the curve of nominal contact pressure versus sealing contact bandwidth under preset preload is analyzed.

5. The method for quantitatively evaluating the sealing performance of pipe joints under lateral displacement according to claim 4, characterized in that, The quantitative evaluation indicators are: ； Where S is a quantitative evaluation index, The nominal contact pressure distribution curve is shown, where x1 is the lower limit of the sealing contact bandwidth of the integral region, and x2 is the upper limit of the sealing contact bandwidth of the integral region.

6. A quantitative evaluation system for the sealing performance of pipe joints under lateral displacement, characterized in that, include: The microscopic calculation module is used to construct a microscopic contact model of a rough surface at the microscopic level and calculate the critical contact pressure of the pipe joint. The macroscopic calculation module is used to construct a finite element model of the pipe joint at the macroscopic level, apply a lateral displacement load in the direction perpendicular to the pipe axis, and obtain the nominal contact pressure distribution curve. The evaluation index calculation module is used to calculate the regional integral formed by the nominal contact pressure distribution curve and the critical contact pressure to obtain a quantitative evaluation index for evaluating the sealing performance of the pipe joint.

7. The quantitative evaluation system for the sealing performance of pipe joints under lateral displacement according to claim 6, characterized in that, In the microscopic calculation module, a microscopic contact model of a rough surface is constructed based on surface roughness information, and the variation law of the contact area between rough surfaces with normal pressure is analyzed.

8. The quantitative evaluation system for the sealing performance of pipe joints under lateral displacement according to claim 7, characterized in that, In the microscopic computing module, the critical contact pressure is: ； Among them, P c Where F is the critical contact pressure, F is the normal pressure, and A is the contact area.

9. The quantitative evaluation system for the sealing performance of pipe joints under lateral displacement according to claim 8, characterized in that, In the macroscopic calculation module, a finite element model of the pipe joint is constructed based on the pipe joint size information, and the curve of nominal contact pressure changing with sealing contact bandwidth under preset preload is analyzed.

10. The quantitative evaluation system for the sealing performance of pipe joints under lateral displacement according to claim 9, characterized in that, In the evaluation index calculation module, the quantitative evaluation index is: ； Where S is a quantitative evaluation index, The nominal contact pressure distribution curve is shown, where x1 is the lower limit of the sealing contact bandwidth of the integral region, and x2 is the upper limit of the sealing contact bandwidth of the integral region.

Images