A full elastic high-pressure self-tightening clamp and sealing method thereof

Abstract

The present application relates to self-tightening clamp technology field, specifically disclose a kind of full elasticity high pressure self-tightening clamp and sealing method, wherein clamp includes two oppositely arranged sleeve joints and the sealing ring between two sleeve joints, the two ends of sealing ring are formed with the sealing lip portion matched with the inner diameter of two sleeve joints, support rib portion is further provided in sealing lip portion, and support rib portion and sealing lip portion form "T" shape between, the surface of sealing lip portion forms stepped slope face;Sleeve joint inside is also provided with sealing cone surface corresponding stepped slope face position, initially, sealing cone surface is contacted with stepped slope face, and gradually increases with the internal pressure of sleeve joint, sealing cone surface and stepped slope face gradually overall adhesion to form spherical sealing surface;Stepped slope face includes first sealing slope, second sealing slope and third sealing slope, the inclination angle of first sealing slope, second sealing slope and third sealing slope gradually decreases;Realize that the greater the internal pressure, the more reliable self-tightening sealing effect.

Description

Technical Field

[0001] This invention relates to the field of self-tightening flange technology, and specifically discloses a fully elastic high-pressure self-tightening flange and its sealing method. Background Technology

[0002] In the field of pipeline connection, especially in fluid transportation systems under high pressure conditions, the sealing performance and structural reliability of pipeline connectors are directly related to the safe and stable operation of the system. At present, traditional pipeline connection methods mostly adopt flange connection structures, which mainly use multiple main bolts to fasten the mating flanges and rely on the sealing gaskets (such as rubber gaskets, metal gaskets, etc.) between the flanges to achieve sealing.

[0003] However, traditional flange connections have many inherent drawbacks: On the one hand, to ensure sealing performance under high pressure, traditional flanges often require a large flange body and a large number of high-strength main bolts, resulting in a large overall structure that is heavy and bulky. This not only increases material costs and installation space requirements but also makes installation and disassembly cumbersome and maintenance difficult. On the other hand, the sealing performance of traditional flanges heavily depends on the physical properties of the gasket. The gasket must bear the strength load from the bolt preload while also fulfilling its sealing function. It is prone to aging, deformation, or even cracking due to long-term stress, temperature changes, or media corrosion, leading to sealing failures such as leaks. Furthermore, the poor strength matching between the gasket and the pipe body further shortens the service life of the connection structure and increases maintenance costs.

[0004] In recent years, to address the aforementioned problems of traditional flange connections, new types of pipe connectors, such as high-pressure self-tightening flanges, have gradually emerged both domestically and internationally. These connectors attempt to achieve reliable sealing under high pressure through optimized structural design. However, existing high-pressure self-tightening flanges still have significant shortcomings in practical applications: First, the sealing structure design is unreasonable, with most using a single sealing surface contact. Initially, it is difficult to form a stable line contact or narrow-band seal, resulting in uneven distribution of sealing pressure and making local leakage prone to occur under high-pressure conditions. Second, the fitting accuracy between the sealing element and the sleeve is insufficient. The sealing surface has low machining accuracy and poor fit, and lacks an effective elastic deformation compensation mechanism. During pre-tightening or changes in internal pressure, the sleeve sealing surface is easily damaged due to stress concentration, significantly shortening the service life of the sleeve. Third, there is a lack of a clear pre-tightening-self-tightening coordination mechanism during the sealing process. The transmission path of the initial pre-tightening force and the internal pressure self-tightening force is unclear. When the internal pressure of the medium increases, the sealing pressure cannot increase synchronously with the internal pressure, and may even lead to separation of the sealing surface due to insufficient structural rigidity, thereby reducing the reliability of the seal.

[0005] Therefore, there is an urgent need in this field to propose a fully elastic high-pressure self-tightening flange and its sealing method. Summary of the Invention

[0006] The purpose of this invention is to provide a fully elastic high-pressure self-tightening flange and its sealing method, so as to at least solve one of the above-mentioned technical problems existing in the prior art.

[0007] Specifically, the present invention is achieved through the following technical solution:

[0008] A fully elastic high-pressure self-tightening flange includes two opposing sleeves and a sealing ring located between the two sleeves. The two ends of the sealing ring are respectively formed with sealing lips that match the inner diameter of the two sleeves. A support rib is also provided in the middle of the sealing lip, and the support rib and the sealing lip form a "T" shape. The surface of the sealing lip forms a stepped slope.

[0009] The sleeve is also provided with a sealing cone surface at the position corresponding to the stepped slope inside. Initially, the sealing cone surface is in contact with the stepped slope, and as the internal pressure of the sleeve gradually increases, the sealing cone surface and the stepped slope gradually fully fit together to form a spherical sealing surface.

[0010] The stepped inclined surface includes a first sealing inclined surface, a second sealing inclined surface, and a third sealing inclined surface, and the inclination angles of the first sealing inclined surface, the second sealing inclined surface, and the third sealing inclined surface gradually decrease.

[0011] It should be noted that this technical solution uses a T-shaped sealing ring, composed of a sealing lip and a middle support rib. It cleverly utilizes the stepped inclined surfaces on the sealing lip surface (i.e., the first, second, and third sealing inclined surfaces with gradually decreasing inclination angles) to engage with the sealing cone surface inside the sleeve. In the initial state, the sealing cone surface and the stepped inclined surface make initial contact. The support rib prevents the sealing ring from yielding entirely, and a stable initial line contact seal is formed through the first sealing inclined surface. As the internal pressure of the sleeve increases, the sealing ring undergoes elastic deformation due to the internal pressure. The second and third sealing inclined surfaces of the stepped inclined surface gradually adhere to the sealing cone surface, ultimately forming a... The comprehensive spherical sealing surface utilizes the decreasing slope angle to achieve uniform distribution and gradual increase of sealing pressure, solving the problem of easy overall yielding of existing seals. Furthermore, through the progressive fitting design of multi-step slopes and sealing cone surfaces, a pre-tightening-self-tightening synergistic mechanism of "initial line contact - internal pressure increase surface contact" is constructed. This effectively compensates for the defects of traditional flanges, such as large volume and easy failure of gaskets, as well as the uneven sealing pressure and lack of self-tightening synergy of existing self-tightening flanges with a single sealing surface. Ultimately, it achieves a fully elastic self-tightening sealing effect under high pressure conditions, with sealing performance increasing with internal pressure, significantly improving the reliability, sealing performance and service life of the connection structure.

[0012] Furthermore, the first sealing bevel, the second sealing bevel, and the third sealing bevel have a smooth transition.

[0013] Based on the above technical solution, the smooth transition between the first, second, and third sealing bevels further optimizes the force transmission and deformation continuity during the contact process between the sealing ring and the sealing cone surface of the sleeve. In the initial pre-tightening stage, the smooth transition structure ensures uniform stress distribution when the first sealing bevel contacts the sealing cone surface, avoiding localized stress concentration caused by sharp angles or abrupt changes at the bevel joints, thus protecting the sealing surface from early damage. In the self-tightening stage as the internal pressure of the sleeve increases, with the intensified elastic deformation of the sealing ring, the smooth transition structure allows for continuous connection of the contact areas between the sealing bevels as the second and third sealing bevels sequentially contact the sealing cone surface, forming an uninterrupted sealing band expansion process. This ensures a gradual increase in sealing pressure from the first to the third bevel, while avoiding sealing gaps or stress peaks caused by abrupt changes at the bevel joints, effectively preventing the risk of medium leakage from the joint under high pressure.

[0014] Meanwhile, it further reduces material fatigue damage to the sealing ring during repeated elastic deformation. Combined with the T-shaped support ribs, it further ensures that the sealing ring is always within the full elastic deformation range, ultimately significantly improving the sealing performance, stability and service life of the sealing structure. It also makes up for the defects of uneven sealing pressure and easy leakage caused by a single sealing surface or a non-smooth transition slope in the existing technology.

[0015] Furthermore, it also includes a retainer, which is symmetrically arranged around the central axis of the sleeve and fastened by a ball bolt. The bottom of the retainer is open and recessed inward to form a groove, and the opening size of the groove gradually decreases from bottom to top.

[0016] Based on the above technical solution, the symmetrically arranged ferrule combined with the spherical bolt avoids unilateral stress concentration caused by force offset during pre-tightening, thus ensuring force balance on both sides of the sleeve. The design of the groove opening size decreasing from bottom to top forms a wedge fit with the boss of the sleeve. Under the action of bolt pre-tightening force, the inner wall of the groove generates uniform axial pressure on the boss, efficiently converting the bolt force into contact pressure between the sealing ring and the sealing cone surface of the sleeve. This avoids the problems of dispersed tightening force or local overload in traditional structures and reduces the requirements for bolt installation accuracy. Simultaneously, the adaptive fit between the groove and the boss ensures that the sealing ring is always subjected to a stable pre-tightening force, providing reliable force support for the initial line contact seal. This, combined with the stepped inclined surface design of the sealing ring, further enhances the stability and reliability of the sealing structure under high-pressure conditions.

[0017] Specifically, the outer surfaces of the two sleeves that are close to each other form a boss that matches the slot, and there is a fastening gap between the bottom of the slot and the top of the boss.

[0018] Based on the above technical solution, the matching structure of the boss and the slot ensures that the axial clamping force of the sleeve on the sleeve is evenly distributed in the circumferential direction, avoiding local overload caused by misalignment, ensuring stable contact pressure between the sealing ring and the sealing cone surface of the sleeve, and the existence of the tightening gap provides the necessary stroke for the compression of the sleeve to the sealing ring during the pre-tightening stage, and ensures that the sealing ring maintains the gradual increase of the sealing specific pressure with the increase of the internal pressure through elastic deformation under the action of internal pressure, effectively making up for the defects of uneven tightening force and easy damage to the seal caused by the lack of matching structure and gap design in the prior art.

[0019] Furthermore, there is a contact gap between the end faces of the two bosses and the surface of the support rib of the sealing ring.

[0020] Based on the above technical solution, the contact gap provides necessary space for the elastic deformation of the sealing ring and the self-tightening of the sealing process. In other words, during the pre-tightening stage, it avoids premature rigid contact between the end face of the boss and the supporting rib, ensuring that the sealing lip of the sealing ring can fully generate radial elastic compression under the action of bolt pre-tightening force. This allows the stepped inclined surface to form a stable initial line contact seal with the sealing cone surface of the sleeve, ensuring the effective establishment of the initial sealing specific pressure. During the self-tightening stage when the internal pressure of the sleeve increases, the internal pressure will push the sealing lip of the sealing ring to produce a slight lifting tendency. The contact gap provides buffer space for this displacement, allowing the stepped inclined surface of the sealing lip to gradually fit with the sealing cone surface under the combined action of radial rebound and internal pressure thrust, ultimately achieving a 360° spherical sealing fit.

[0021] A fully elastic high-pressure self-tightening flange sealing method, based on the aforementioned fully elastic high-pressure self-tightening flange, specifically includes the following steps:

[0022] Step 1, Assembly and Positioning: Weld the two sleeves to the pipe respectively, and place the sealing ring between the two oppositely positioned sleeves, so that the stepped inclined surface of the sealing lip of the sealing ring initially corresponds to the sealing cone surface of the sleeve. At the same time, install the ferrule symmetrically with the central axis of the sleeve as the center, so that the groove of the ferrule initially matches the boss of the sleeve, and ensure that the ball bolt assembly is in place.

[0023] Step 2, Install and tighten: Tighten the ball bolts to connect and secure the two ferrules, so that the groove of the ferrule applies axial pressure to the boss of the sleeve, causing the sleeve to gradually move closer to the support rib of the sealing ring for compression.

[0024] Step 3, initial seal formation: continuously tighten the ball bolt until the end face of the boss of the sleeve and the support rib are close to the preset contact gap, and the bottom of the slot and the top of the boss maintain a preset fastening distance. At this time, a stable line contact seal is formed between the sealing lip and the sealing cone surface.

[0025] The sealing method based on the above technical solution solves the problems of assembly misalignment, uneven pre-tightening, and unreliable initial sealing in traditional methods. It also lays the foundation for enhanced sealing during the subsequent internal pressure self-tightening stage, ultimately improving the stability and reliability of the self-tightening seal under high-pressure conditions. Specifically:

[0026] This method ensures precise alignment between the stepped inclined surface of the sealing ring and the sealing cone surface of the sleeve, and between the ferrule groove and the boss of the sleeve, during the assembly and positioning stage. This provides a structural foundation for subsequent sealing. In the subsequent installation and tightening stage, axial pressure is evenly transmitted using ball bolts, causing the sealing ring to compress systematically and preventing force misalignment. During the initial seal formation stage, controlling the preset contact gap and tightening distance, in conjunction with the first sealing inclined surface, forms a narrow-band seal and achieves the initial sealing pressure. This ensures the reliability of the initial seal while also allowing for elastic deformation space for the sealing ring. The entire process achieves precise transmission of preload, orderly contact of the sealing surfaces, and stable establishment of the initial sealing pressure.

[0027] Furthermore, in step 3, when a stable line contact seal is formed between the sealing lip and the sealing cone surface, the first sealing slope of the stepped slope forms a narrow band seal with the sealing cone surface, and ensures that the contact stress between the first sealing slope and the sealing cone surface reaches the initial sealing pressure.

[0028] Based on the above technical solution, the narrow-band contact between the first sealing slope and the sealing cone surface concentrates the sealing stress, ensuring that a high-strength initial seal can be formed during the pre-tightening stage. This avoids the problem of insufficient sealing pressure caused by traditional wide-face contact. At the same time, the precise initial sealing pressure provides a stable pre-tightening foundation for the sealing ring, ensuring reliable sealing under low pressure / pre-tightening conditions. It also reserves elastic deformation space for the gradual fit of the second and third sealing slopes when the internal pressure increases, so that the initial seal and the subsequent fully elastic self-tightening of the sealing ring can work together to improve the overall sealing stability.

[0029] Furthermore, it also includes step 4, the internal pressure self-tightening sealing stage. When the medium is introduced into the sleeve, the internal pressure of the medium acts on the sealing ring, causing the sealing ring to tend to push upward. When the sealing ring pushes upward, the sleeve is subjected to the tightening force of the ferrule and the ball bolt, as well as the upward force of the sealing ring, which causes the end face of the boss of the sleeve to gradually fit with the supporting rib of the sealing ring under the action of radial pressure. At the same time, the sealing lip of the sealing ring undergoes elastic deformation due to the internal pressure of the medium. As the internal pressure gradually increases, the second and third sealing slopes of the stepped slope of the sealing lip gradually come into full sealing fit with the sealing cone to form a spherical seal. As a result, the sealing specific pressure between the stepped slope of the sealing ring and the sealing cone of the sleeve increases with the increase of the internal pressure of the medium, and finally achieves a fully elastic self-tightening seal.

[0030] Based on the above technical solution, in step 4, the internal pressure of the medium drives the sealing ring to generate an upward ejection tendency, causing the end face of the sleeve boss to gradually fit with the supporting rib of the sealing ring to stabilize the force transmission path. Simultaneously, the elastic deformation of the sealing lip allows the second and third sealing bevels of the stepped slope to gradually fit with the sealing cone surface of the sleeve, forming a spherical seal. This achieves a dynamic self-tightening mechanism where the sealing specific pressure increases synchronously with the increase of the internal pressure of the medium. This process increases the sealing contact area through the expanded fit of multiple sealing bevels and achieves self-adaptation of the sealing surface through fully elastic deformation, effectively solving the defect of traditional sealing structures where sealing performance easily decreases with increasing internal pressure. Ultimately, this enhances the sealing reliability with increasing operating pressure, significantly improving sealing stability and system operational safety under high-pressure environments.

[0031] Compared with the prior art, the present invention has at least the following advantages and beneficial effects:

[0032] (1) The present invention uses a T-shaped sealing ring to prevent the sealing ring from yielding as a whole by using the supporting ribs. At the same time, it achieves a fully elastic self-tightening seal by using the elastic deformation of the sealing lip. This solves the problem that traditional seals are prone to yielding as a whole due to excessive pre-tightening force, ensuring that the sealing ring is always within the elastic deformation range and improving the mechanical stability of the sealing structure.

[0033] (2) This invention achieves a full sealing process by designing the angle difference between the stepped inclined surface of the sealing lip (including the first, second and third sealing inclined surfaces) and the sealing cone surface of the sleeve, and by cleverly combining the internal pressure self-tightening mechanism. The sealing specific pressure of the sealing ring increases synchronously with the increase of the internal pressure of the medium, thus constructing a dynamic self-tightening mechanism that increases synchronously with the increase of the internal pressure of the medium. With the help of the elastic deformation of the sealing lip and the expansion of the multi-sloping surface, the self-tightening effect of the greater the internal pressure, the more reliable the seal is achieved, thus making up for the defect that the sealing performance of the traditional sealing structure is easy to decay with the increase of internal pressure.

[0034] (3) The present invention ensures that the preload is evenly transmitted to the sealing surface by symmetrical arrangement of the ferrule, fastening of the ball bolt and matching gap design of the groove and the boss. At the same time, it provides a space for full elastic deformation of the sealing ring, avoiding damage to the sealing surface caused by stress concentration. Compared with the problems of large size, complicated installation and easy damage of existing flange components, the present invention significantly reduces material costs and maintenance difficulty, and extends the service life of the connection structure.

[0035] (4) The sealing method of the present invention ingeniously constructs a fully elastic self-tightening synergistic mechanism of pre-tightening stage line seal + internal pressure stage narrow band seal through each step. During pre-tightening, the initial seal is formed by bolt force. Then, based on the action of internal pressure of the medium, the sealing ring is forced to rebound radially and fully fit with the conical surface of the sleeve, realizing the fully elastic self-tightening seal of the self-tightening flange. This not only ensures the reliability of low-pressure pre-tightening, but also strengthens the high-pressure self-tightening sealing effect through internal pressure self-tightening, significantly improving the safety of the self-tightening flange under extreme working conditions. Attached Figure Description

[0036] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0037] Figure 1 This is a schematic diagram of the overall structure of the self-tightening clamp according to Embodiment 1 of the present invention;

[0038] Figure 2 This is a schematic diagram of the internal structure of the self-tightening clamp in the DD direction according to Embodiment 1 of the present invention;

[0039] Figure 3 This is a partially enlarged structural schematic diagram of the sealing ring in Embodiment 1 of the present invention;

[0040] Figure 4 This is a schematic diagram of the sealing method steps in Embodiment 2 of the present invention;

[0041] Figure 5 This is a partially enlarged structural diagram of the sealing ring in Embodiment 3 of the present invention;

[0042] Figure 6 This is a partial structural schematic diagram of the gradient guide portion of the present invention.

[0043] In the above figures, the reference numerals represent: 1, sleeve; 11, sealing cone surface; 12, boss; 2, sealing ring; 21, sealing lip; 211, first sealing bevel; 212, second sealing bevel; 213, third sealing bevel; 22, sealing rib; 3, ferrule; 31, groove; 4, ball bolt; 5, gradient guide; 51, guide plate. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The illustrative embodiments and descriptions of this invention are only for explaining the invention and are not intended to limit the invention. The embodiments described below are some, but not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0045] In the following description, numerous specific details are set forth to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other embodiments, well-known structures, materials, or methods have not been specifically described to avoid obscuring the invention. Unless otherwise specified, the materials, instruments, and reagents used in the following embodiments are commercially available. Unless otherwise specified, the techniques used in the embodiments are conventional methods well known to those skilled in the art.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0047] Example 1:

[0048] Please see Figures 1 to 3 As shown, this embodiment discloses a fully elastic high-pressure self-tightening flange, including two oppositely arranged sleeves 1 and a sealing ring 2 located between the two sleeves 1. The two ends of the sealing ring 2 are respectively formed with sealing lips 21 that match the inner diameter of the two sleeves 1. A support rib is also provided in the middle of the sealing lip 21, and a "T" shape is formed between the support rib and the sealing lip 21. The surface of the sealing lip 21 forms a stepped slope.

[0049] The sleeve 1 is also provided with a sealing cone surface 11 at the position corresponding to the stepped inclined surface inside. Initially, the sealing cone surface 11 is in contact with the stepped inclined surface. As the internal pressure of the sleeve 1 gradually increases, the sealing cone surface 11 and the stepped inclined surface gradually fully fit together to form a spherical sealing surface.

[0050] The stepped inclined surface includes a first sealing inclined surface 211, a second sealing inclined surface 212, and a third sealing inclined surface 213, with the inclination angles of the first sealing inclined surface 211, the second sealing inclined surface 212, and the third sealing inclined surface 213 gradually decreasing.

[0051] Based on the above embodiments, it should be noted that in specific implementations, the sealing ring 2, composed of a sealing lip 21 and an intermediate support rib, forms a "T" shape. It cleverly utilizes the stepped inclined surface of the sealing lip 21 (i.e., the first, second, and third sealing inclined surfaces 213 with gradually decreasing inclination angles) to cooperate with the sealing cone surface 11 inside the sleeve 1. In the initial state, the sealing cone surface 11 initially contacts the stepped inclined surface. At this time, the end faces of the two sleeve 1 bosses 12 have a contact gap of 0 < L < 1 mm with the surface of the support rib of the sealing ring 2. The supporting rib helps prevent the sealing ring 2 from yielding as a whole. A sealing bevel 211 forms a stable initial line contact seal, with an initial sealing pressure of up to 253.8 MPa. As the internal pressure of the sleeve 1 increases, the sealing ring 2 undergoes radial elastic compression due to the internal pressure (compression amount can reach 0.11 mm). The gap between the sleeve 1 and the supporting rib of the sealing ring 2 shrinks from 0.3 mm to 0. At this time, the second sealing bevel 212 and the third sealing bevel 213 of the stepped bevel gradually fit into the sealing cone 11 in sequence, eventually forming a complete spherical sealing surface. This utilizes the decreasing angle characteristics of each sealing bevel and the angle difference with the sealing cone 11 to achieve a uniform distribution and gradual increase in sealing pressure.

[0052] Thus, the supporting rib of the sealing ring 2 solves the problem of easy overall yielding of existing seals. Furthermore, the progressive fit design of the stepped inclined surface of the sealing lip 21 and the sealing cone surface 11 effectively compensates for the defects of traditional flanges, such as large volume, easy failure of sealing gaskets, uneven sealing pressure of the single sealing surface of existing self-tightening flanges, and lack of self-tightening coordination. Finally, it achieves a fully elastic self-tightening sealing effect under high pressure conditions, with the sealing performance increasing with the increase of internal pressure, which significantly improves the reliability, sealing performance and service life of the connection structure.

[0053] As an example, in the initial sealing state, the seal between sleeve 1 and sealing ring 2 is achieved by the sealing cone surface 11 and the stepped inclined surface fitting together, at which point the angle difference β between them is ≤3°. When the internal pressure reaches 0 < P < 10 MPa, the first sealing inclined surface 211 and the sealing cone surface 11 are completely fitted together, and the angle difference β between them is 2° < β < 3°. When the internal pressure reaches 10 MPa < P < 30 MPa, both the first sealing inclined surface 211 and the second sealing inclined surface 212 are fitted together with the sealing cone surface 11, at which point the angle difference β between the stepped inclined surface and the sealing cone surface 11 is 1° < β < 2°. When the internal pressure reaches P ≥ 30 MPa, the first sealing inclined surface 211, the second sealing inclined surface 212, and the third sealing inclined surface 213 completely form a fully elastic 360° uniform surface contact seal with the sealing cone surface 11, at which point the angle β between the stepped inclined surface and the sealing cone surface 11 is 0° < β < 1°.

[0054] Additionally, it should be noted that in this embodiment, the thickness t of the sealing lip 21 of the sealing ring 2 satisfies 1mm < t < 10mm.

[0055] In some preferred embodiments, in Figure 3 As shown in the figure, there is a smooth transition between the first sealing bevel 211, the second sealing bevel 212 and the third sealing bevel 213.

[0056] In this embodiment, the smooth transition between the first sealing bevel 211, the second sealing bevel 212, and the third sealing bevel 213 further optimizes the force transmission and deformation continuity during the contact process between the stepped bevel of the sealing lip 21 and the sealing cone surface 11 of the sleeve 1. In the initial pre-tightening stage, the smooth transition structure ensures uniform stress distribution when the first sealing bevel 211 contacts the sealing cone surface 11, avoiding local stress concentration caused by sharp edges or abrupt changes at the bevel joint (the circular runout of the sealing surface is controlled within 0.01 mm), thus protecting the sealing surface from early damage. In the self-tightening stage where the internal pressure of the sleeve 1 increases, as the elastic deformation of the sealing ring 2 intensifies, the smooth transition structure allows the contact areas between the sealing bevels to be continuous. The continuous connection (ensuring the sealing surface fit meets the requirement that the contact cone surface fit between the ferrule 3 and the sleeve 1 is greater than 85%) forms a continuous sealing band expansion process. This ensures a gradual increase in sealing pressure from the first to the third inclined plane, while avoiding sealing gaps or stress peaks caused by abrupt changes in the inclined plane connection, effectively preventing the risk of medium leakage from the connection point under high pressure. At the same time, it further reduces material fatigue damage to the sealing ring 2 during repeated elastic deformation. Combined with the support ribs of the sealing ring 2, it further ensures that the sealing ring 2 is always within the full elastic deformation range (elastic deformation does not exceed the material yield limit). Ultimately, it significantly improves the sealing performance, stability, and service life of the sealing structure, making up for the defects of uneven sealing pressure and easy leakage caused by a single sealing surface or a non-smooth transition inclined plane in the prior art.

[0057] In a further embodiment, in Figure 1 and Figure 2 As shown in the figure, it also includes a retainer 3, which is symmetrically arranged around the central axis of the sleeve 1 and fastened by a ball bolt 4. The bottom of the retainer 3 is open and recessed inward to form a groove 31, and the opening size of the groove 31 gradually decreases from bottom to top.

[0058] The above embodiment, through the symmetrical arrangement of the ferrule 3 and the ball bolt 4, avoids unilateral stress concentration caused by force offset during pre-tightening, thereby ensuring the force balance on both sides of the sleeve 1. The design of the groove 31 with the opening size decreasing from bottom to top can form a wedge fit with the boss 12 of the sleeve 1. Under the action of bolt pre-tightening force, the inner wall of the groove 31 generates uniform axial pressure on the boss 12, efficiently converting the bolt force into the contact pressure between the sealing ring 2 and the sealing cone surface 11 of the sleeve 1. This avoids the problem of dispersed fastening force or local overload in traditional structures and reduces the requirements for bolt installation accuracy. At the same time, through the adaptive fit of the groove 31 and the boss 12, it is ensured that the sealing ring 2 is always subjected to a stable pre-tightening force, providing a reliable force source support for the initial line contact seal. This, combined with the stepped inclined surface design of the sealing ring 2, further improves the stability and reliability of the sealing structure under high pressure conditions.

[0059] In some preferred embodiments, in Figure 3 As shown in the figure, the outer surfaces of the two sleeves 1 that are close to each other form a boss portion 12 that is adapted to the slot 31, and there is a fastening gap between the bottom of the slot 31 and the top of the boss portion 12.

[0060] In the above embodiments, the fitting structure of the boss portion 12 and the groove 31 ensures that the axial clamping force of the sleeve 3 on the sleeve 1 is evenly distributed in the circumferential direction, avoiding local overload caused by misalignment. Furthermore, the surface finish of the contact surface between the sleeve 3 and the sleeve 1 is higher than 3.2, which ensures stable contact pressure between the sealing ring 2 and the sealing cone surface 11 of the sleeve 1. The presence of the fastening gap provides the necessary stroke for the compression of the sleeve 1 towards the sealing ring 2 during the pre-tightening stage, and ensures that the sealing ring 2 maintains the gradual increase of the sealing specific pressure as the internal pressure increases through elastic deformation under the action of internal pressure. This effectively makes up for the defects of uneven fastening force and easy damage to the seal caused by the lack of fitting structure and gap design in the prior art.

[0061] In a further embodiment, such as Figure 3 As shown, there is a contact gap between the end faces of the two bosses 12 and the surface of the support rib of the sealing ring 2.

[0062] For example, this contact gap (within the range of 0-1mm) provides necessary space for the elastic deformation of the sealing ring 2 and the self-tightening of the sealing process. That is, in the pre-tightening stage, it avoids premature rigid contact between the end face of the boss 12 and the support rib, ensuring that the sealing lip 21 of the sealing ring 2 can generate sufficient radial elastic compression under the action of the bolt pre-tightening force, so that the stepped slope and the sealing cone surface 11 of the sleeve 1 form a stable initial line contact seal, ensuring the effective establishment of the initial sealing pressure. In the self-tightening stage when the internal pressure of the sleeve 1 increases, the internal pressure will push the sealing lip 21 of the sealing ring 2 to produce a slight lifting tendency, and the contact gap provides a buffer space for this displacement, so that under the combined action of radial rebound and internal pressure thrust, the stepped slope of the sealing lip 21 can gradually fit with the sealing cone surface 11 in sequence, and finally achieve a 360° spherical sealing fit, ensuring that the sealing pressure increases synchronously with the increase of internal pressure.

[0063] Example 2:

[0064] Please see Figure 4 As shown, based on a fully elastic high-pressure self-tightening flange of Embodiment 1, this embodiment provides a sealing method for a fully elastic high-pressure self-tightening flange. Specifically, the method includes the following steps:

[0065] Step 1, Assembly and Positioning: Weld the two sleeve sections 1 to the pipeline respectively, and place the sealing ring 2 between the two oppositely arranged sleeve sections 1, so that the stepped inclined surface of the sealing lip 21 of the sealing ring 2 initially corresponds to the sealing cone surface 11 of the sleeve section 1. At the same time, install the ferrule 3 symmetrically with the central axis of the sleeve section 1 as the center, so that the groove 31 of the ferrule 3 initially matches the boss part 12 of the sleeve section 1, and ensure that the ball bolt 4 assembly is in place.

[0066] Step 2, install and tighten, tighten the ball bolt 4 to connect and tighten the two ferrules 3, so that the groove 31 of the ferrule 3 applies axial pressure to the boss 12 of the sleeve 1, causing the sleeve 1 to gradually move closer to the support rib of the sealing ring 2 for compression.

[0067] Step 3, initial seal formation, continuously tighten the ball bolt 4 until the end face of the boss 12 of the sleeve 1 approaches the support rib to the preset contact gap, and the bottom of the groove 31 and the top of the boss 12 maintain a preset fastening distance. At this time, a stable line contact seal is formed between the sealing lip 21 and the sealing cone surface 11.

[0068] The sealing method based on this embodiment solves the problems of assembly misalignment, uneven pre-tightening, and unreliable initial sealing in traditional methods. It also lays the foundation for enhanced sealing during the subsequent internal pressure self-tightening stage, ultimately improving the stability and reliability of the self-tightening seal under high-pressure conditions. Specifically:

[0069] This method ensures precise alignment between the stepped inclined surface of the sealing ring 2 and the sealing cone surface 11 of the sleeve 1, and between the groove 31 of the ferrule 3 and the boss 12 of the sleeve 1, during the assembly and positioning stage. This provides a structural foundation for subsequent sealing. During the installation and tightening stage, axial pressure is evenly transmitted using ball bolts 4, causing the sealing ring 2 to compress systematically and preventing force deviation. In the initial seal formation stage, by controlling the preset contact gap and tightening distance, a narrow-band seal is formed in conjunction with the first sealing inclined surface 211, achieving the initial sealing pressure. This ensures the reliability of the initial seal while also providing space for elastic deformation of the sealing ring 2. The entire process achieves precise transmission of preload, orderly contact of the sealing surfaces, and stable establishment of the initial sealing pressure.

[0070] In some preferred embodiments, in step 3, when a stable line contact seal is formed between the sealing lip 21 and the sealing cone 11, the first sealing slope 211 of the stepped slope forms a narrow band seal with the sealing cone 11, and ensures that the contact stress between the first sealing slope 211 and the sealing cone 11 reaches the initial sealing pressure.

[0071] Based on the above implementation method, the narrow-band contact between the first sealing slope 211 and the sealing cone 11 concentrates the sealing stress, ensuring that a high-strength initial seal can be formed during the pre-tightening stage. This avoids the problem of insufficient sealing pressure caused by traditional wide-face contact. At the same time, the precise initial sealing pressure provides a stable pre-tightening basis for the sealing ring 2, ensuring reliable sealing under low pressure / pre-tightening conditions. It also reserves elastic deformation space for the gradual fit of the second and third sealing slopes 213 when the internal pressure increases later, so that the initial seal and the subsequent fully elastic self-tightening of the sealing ring 2 can work together to improve the overall sealing stability.

[0072] In a further embodiment, step 4, the internal pressure self-tightening sealing stage, is also included. When the medium is introduced into the sleeve 1, the internal pressure of the medium acts on the sealing ring 2, causing the sealing ring 2 to tend to push upward. When the sealing ring 2 pushes upward, the sleeve 1 is subjected to the tightening force of the ferrule 3 and the ball bolt 4, as well as the upward pushing force of the sealing ring 2. This causes the end face of the boss portion 12 of the sleeve 1 to gradually fit with the supporting rib of the sealing ring 2 under the action of radial pressure. At the same time, the sealing lip 21 of the sealing ring 2 undergoes elastic deformation due to the internal pressure of the medium. As the internal pressure gradually increases, the second sealing slope 212 and the third sealing slope 213 of the stepped slope of the sealing lip 21 gradually come into full sealing fit with the sealing cone surface 11 to form a spherical seal. As a result, the sealing pressure ratio between the stepped slope of the sealing ring 2 and the sealing cone surface 11 of the sleeve 1 increases with the increase of the internal pressure of the medium, and finally achieves a fully elastic self-tightening seal.

[0073] Based on the above implementation method, in step 4, the internal pressure of the medium drives the sealing ring 2 to generate an upward pushing tendency, causing the end face of the boss portion 12 of the sleeve 1 to gradually fit with the supporting rib of the sealing ring 2 to stabilize the force transmission path. At the same time, the elastic deformation of the sealing lip 21 causes the second sealing slope 212 and the third sealing slope 213 of the stepped slope to gradually fit with the sealing cone surface 11 of the sleeve 1 to form a spherical seal, realizing a dynamic self-tightening mechanism in which the sealing specific pressure increases synchronously with the increase of the internal pressure of the medium. This process increases the sealing contact area through the expansion and fitting of multiple sealing slopes, and achieves self-adaptation of the sealing surface through full elastic deformation, effectively solving the defect that the sealing performance of traditional sealing structures is prone to decay with the increase of internal pressure. Ultimately, the sealing reliability increases with the operating pressure, significantly improving the sealing stability and system operation safety under high pressure.

[0074] Example 3:

[0075] This embodiment is based on Embodiment 1 above. Please refer to [link / reference]. Figure 5 and Figure 6 The difference lies in that: multiple guide plates 51 are provided on the inner wall of the sleeve 1 near the sealing cone surface 11. The multiple guide plates 51 are spliced ​​together to form a gradient guide part 5. The inner diameter of the gradient guide part 5 decreases along the direction near the sealing lip 21 to form an annular guide channel.

[0076] As should be understood, the gradient guide section 5 refers to an annular guide channel formed by splicing multiple guide ramps, whose inner diameter continuously decreases along the fluid flow direction. Specifically, this can be achieved using a conical surface or a stepped gradient surface, as shown in the attached diagram. Figure 6As shown, it adopts a conical curved surface; through the setting of the gradual guide part 5, when the high-pressure medium enters the sealing lip 21 of the sealing ring 2 through the sealing cone surface 11, the step height difference between the sealing cone surface 11 and the sealing lip 21 can be further reduced, so that the high-pressure medium can smoothly enter the sealing lip 21, thereby reducing the turbulence disturbance and local pressure loss caused by the step height difference during the medium flow, avoiding high-frequency impact wear on the sealing surface caused by eddies due to abrupt changes in the step, and the convergent flow channel formed by the gradual guide part 5 will generate a "velocity- The "pressure conversion effect" refers to the phenomenon where, as the high-pressure medium flows along the gradual guide 5 towards the sealing lip 21, the flow velocity steadily increases along the path, while a uniformly distributed circumferential static pressure is formed on the inner side of the sealing lip 21. This static pressure actively applies a radially outward thrust to the sealing lip 21, which, in turn, works synergistically with the elastic deformation of the sealing ring 2 under the action of the medium's internal pressure. This results in a faster contact speed and more uniform contact pressure between the sealing lip 21 and the sealing cone surface 11, allowing the sealing specific pressure of the flange to be enhanced in advance by the fluid pressure even when the medium is flowing. Especially during system start-up or pressure fluctuations, it can effectively suppress the micro-gap of the sealing surface caused by sudden pressure changes, significantly reducing the risk of leakage under high-pressure pulse conditions. At the same time, the smoothing effect of the gradual guide 5 on the medium flow can also reduce cavitation or erosion near the sealing surface between the sealing ring 2 and the sleeve 1. Combined with the stepped slope design of the sealing lip 21, this greatly extends the service life of the fully elastic self-tightening flange.

[0077] It should be noted that the structures, proportions, sizes, etc., illustrated in the accompanying drawings of this specification are all schematic diagrams, intended only to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0078] Furthermore, the terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity of description and are not intended to limit the scope of the invention. Any changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

Claims

1. A method of all-elastomeric high pressure self-energizing Kalman seal, characterized by, The method is based on a full-elastic high-pressure self-tightening clamp ring, wherein the clamp ring comprises two oppositely arranged sleeve joints (1) and a sealing ring (2) located between the two sleeve joints (1), both ends of the sealing ring (2) are formed with sealing lips (21) matched with the inner diameters of the two sleeve joints (1), and a supporting rib is further arranged in the middle of the sealing lips (21), and the supporting rib and the sealing lips (21) form a "T" shape, and the surface of the sealing lips (21) forms a stepped slope; The inside of the sleeve joint (1) is further provided with a sealing cone surface (11) corresponding to the position of the stepped slope, initially, the sealing cone surface (11) is in contact with the stepped slope, the first sealing slope (211) of the stepped slope forms a narrow strip seal with the sealing cone surface (11), when the medium internal pressure gradually increases in the sleeve joint (1), the sealing lips (21) of the sealing ring (2) are elastically deformed due to the medium internal pressure, and the second sealing slope (212) and the third sealing slope (213) of the stepped slope of the sealing lips (21) gradually form full sealing fit with the sealing cone surface (11) to form a spherical seal; The stepped slope comprises a first sealing slope (211), a second sealing slope (212) and a third sealing slope (213), the inclination angles of the first sealing slope (211), the second sealing slope (212) and the third sealing slope (213) gradually decrease, and the first sealing slope (211), the second sealing slope (212) and the third sealing slope (213) are smoothly connected; A plurality of guide plates (51) are further arranged on the inner wall of the sleeve joint (1) near the position of the sealing cone surface (11), the plurality of guide plates (51) are connected to form a gradually changing guide part (5), the inner diameter of the gradually changing guide part (5) gradually decreases in the direction close to the sealing lips (21) to form an annular guide channel, when the high-pressure medium enters the sealing lips (21) of the sealing ring (2) through the sealing cone surface (11), the step height difference between the sealing cone surface (11) and the sealing lips (21) can be further reduced; The clamp ring further comprises a clamp sleeve (3), the clamp sleeve (3) is symmetrically arranged around the central axis of the sleeve joint (1) and is fastened by a spherical bolt (4), and the bottom of the clamp sleeve (3) is opened and recessed inward to form a clamp groove (31), the opening size of the clamp groove (31) gradually decreases from bottom to top; The outer part of the end face of the two sleeve joints (1) close to each other forms a boss part (12) matched with the clamp groove (31), and there is a fastening spacing between the groove bottom of the clamp groove (31) and the top end of the boss part (12); The end faces of the two boss parts (12) and the surface of the supporting rib of the sealing ring (2) have a contact gap; Specifically, the method comprises the following steps: Step 1, assembly positioning, two sleeve joints (1) are welded with pipes respectively, and a sealing ring (2) is arranged between the two oppositely arranged sleeve joints (1), so that the stepped inclined surface of the sealing lip (21) of the sealing ring (2) is preliminarily corresponded to the sealing cone surface (11) of the sleeve joint (1), and the clamping sleeve (3) is symmetrically installed with the central axis of the sleeve joint (1) as the center, so that the clamping groove (31) of the clamping sleeve (3) is preliminarily adapted to the boss portion (12) of the sleeve joint (1), and the spherical bolt (4) assembly is arranged in place; Step 2, installation and fastening, the spherical bolt (4) is tightened to connect and fasten the two clamping sleeves (3), so that the clamping groove (31) of the clamping sleeve (3) exerts axial pressure on the boss portion (12) of the sleeve joint (1), and drives the sleeve joint (1) to gradually approach and compress the support rib portion of the sealing ring (2); Step 3, initial sealing formation, the spherical bolt (4) is continuously tightened until the end surface of the boss portion (12) of the sleeve joint (1) approaches the support rib portion to a preset contact gap, and a preset fastening interval is maintained between the groove bottom of the clamping groove (31) and the top end of the boss portion (12), at this time, stable linear contact sealing is formed between the sealing lip (21) and the sealing cone surface (11); In the step 3, when stable linear contact sealing is formed between the sealing lip (21) and the sealing cone surface (11), the first sealing inclined surface (211) of the stepped inclined surface forms a narrow band sealing with the sealing cone surface (11), and ensures that the contact stress with the sealing cone surface (11) reaches the initial sealing specific pressure; The method further comprises step 4, internal pressure self-tightening sealing stage, when the medium is introduced into the sleeve joint (1), the internal pressure of the medium acts on the sealing ring (2), so that the sealing ring (2) tends to be pushed upward, and when the sealing ring (2) is pushed upward, the sleeve joint (1) is subjected to the fastening force of the clamping sleeve (3) and the spherical bolt (4) and the upward pushing force of the sealing ring (2), so that the end surface of the boss portion (12) of the sleeve joint (1) gradually adheres to the support rib portion of the sealing ring (2) under the action of radial pressure, and the sealing lip (21) of the sealing ring (2) is elastically deformed due to the internal pressure of the medium, when the internal pressure gradually increases, the second sealing inclined surface (212) and the third sealing inclined surface (213) of the stepped inclined surface of the sealing lip (21) gradually fully seal and adhere to the sealing cone surface (11) to form a spherical surface sealing, so that the sealing specific pressure of the stepped inclined surface of the sealing ring (2) and the sealing cone surface (11) of the sleeve joint (1) is increased with the increase of the internal pressure of the medium, and finally realizes full elastic self-tightening sealing.

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