A flange connection structure with a seal

Abstract

The utility model discloses a flange connecting structure with seal, including connecting flange and sealing mechanism, the inside of connecting flan is provided with annular sealing recess, and adopts the butt joint of threaded connection mode with external pipeline, sealing mechanism is placed in sealing recess, including sealing ring, first sealing assembly and second sealing assembly, wherein, sealing ring is located in the middle part of sealing recess, first sealing assembly includes the outside sealing gasket of outside sealing ring, and the outside sealing gasket adopts elastic soft material, and the side of contact sealing ring is corrugated structure, second sealing assembly includes the inside sealing gasket of inside sealing ring, and the inside sealing gasket adopts elastic soft material, and the side of contact sealing ring is corrugated structure, the utility model solves the problem that the existing flange connecting structure only relies on single sealing pad and inserts between flange sealing surface and seals, and it is easy to cause the uneven compression of gasket or the insufficient adhesion of sealing surface and lead to the sealing failure, and the medium leakage appears.

Description

Technical Field

[0001] This utility model belongs to the technical field of flange sealing structure, specifically relating to a flange connection structure with a seal. Background Technology

[0002] Flange connections are a common connection method in piping systems. They typically consist of a pair of flanges, fasteners, and sealing elements. They are used to connect pipes, valves, or equipment to ensure that the medium does not leak during transportation and to withstand certain pressures and loads. Their function is to achieve detachable connections in the piping system while maintaining the system's sealing and structural integrity. They are widely used in industries such as petroleum, chemical, energy, and shipbuilding.

[0003] Existing flange connection structures still have some problems during use. For example, traditional flange sealing structures usually rely on a single gasket embedded between the flange sealing surfaces for sealing. This simple sealing method is prone to sealing failure and media leakage under long-term use or fluctuations in operating conditions due to uneven gasket compression or insufficient sealing surface fit. Utility Model Content

[0004] In order to overcome the shortcomings of the prior art, the purpose of this utility model is to provide a flange connection structure with a seal. By setting the sealing mechanism, the problem of medium leakage caused by the flange connection structure in the prior art, which relies solely on a single sealing gasket embedded between the flange sealing surfaces for sealing, is solved. This is because the gasket is easily compressed unevenly or the sealing surfaces are not properly fitted.

[0005] To solve the above problems, the technical solution adopted by this utility model is as follows: A flange connection structure with a seal includes a connecting flange and a sealing mechanism; The connecting flange has an annular sealing groove inside and is connected to an external pipe by a threaded connection. The sealing mechanism is placed within the sealing groove and includes a sealing ring, a first sealing assembly, and a second sealing assembly; The sealing ring is located in the middle of the sealing groove; The first sealing assembly includes an outer sealing gasket located outside the sealing ring. The outer sealing gasket is made of an elastic soft material, and the side in contact with the sealing ring has a corrugated structure. The second sealing assembly includes an inner sealing gasket located inside the sealing ring. The inner sealing gasket is made of an elastic soft material, and the side in contact with the sealing ring has a corrugated structure.

[0006] Preferably, the corrugated structure parameters of the outer sealing gasket and the inner sealing gasket include: a corrugation height of 0.8~1.5mm, a spacing of 1.2~2.5mm, a trapezoidal cross-sectional shape, and a side inclination angle of 45°.

[0007] Preferably, a first conical gasket is fixedly connected to the top of the side of the outer sealing gasket that contacts the sealing ring; When the outer sealing gasket is compressed and deformed, the first conical gasket overlaps with the outer edge of the sealing ring.

[0008] Preferably, the first conical gasket is made of a flexible, soft material.

[0009] Preferably, a second conical gasket is fixedly connected to the top of the side of the inner sealing gasket that contacts the sealing ring; When the inner sealing gasket is compressed and deformed, the second conical gasket overlaps with the inner edge of the sealing ring.

[0010] Preferably, the second conical gasket is made of a flexible, soft material.

[0011] Preferably, the bottom wall of the sealing groove is provided with a positioning groove adapted to the sealing ring, and the sealing ring is embedded in the positioning groove.

[0012] Preferably, a stainless steel spring ring is provided in the positioning groove.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: (1) Upgraded sealing mechanism The design employs a corrugated soft gasket (trapezoidal cross-section + 45° side inclination angle) and a tapered gasket overlapping design: the axial preload is directionally converted into radial thrust through the corrugated structure, guiding the material to accurately fill the radial gap between the flange and the sealing ring; the tapered gasket actively overlaps with the edge of the sealing ring, forming a double sealing barrier of "corrugated filling + tapered overlap", realizing an innovation in the sealing mechanism from passive compression to active compensation, effectively solving the leakage problem caused by uneven compression of traditional single gaskets.

[0014] (2) Preload is maintained stably The sealing ring is embedded in the positioning groove to ensure uniform force transmission; the stainless steel spring ring in the positioning groove can absorb the axial displacement caused by the thermal expansion and contraction of the pipeline, continuously maintain the stability of the preload of the sealing gasket, and prevent the loss of preload caused by changes in operating conditions.

[0015] (3) Strong adaptability to working conditions The corrugated structure parameters (height 0.8~1.5mm, spacing 1.2~2.5mm) are adapted to different pressure / temperature conditions; the elastic soft material (oil-resistant rubber, PTFE) and the elastic deformation characteristics of the spring ring can adapt to dynamic displacements such as vibration and thermal expansion and contraction, maintaining the effectiveness of the seal.

[0016] (4) High reliability and long lifespan Multiple sealing redundancy reduces the risk of leakage; uniform pressure distribution avoids local sealing deficiencies; stainless steel components are corrosion resistant, and combined with the resilience of elastic materials, significantly extends service life; compared with traditional designs, the probability of leakage is greatly reduced, improving long-term sealing reliability.

[0017] This structure, through multi-dimensional optimization, comprehensively improves the sealing performance and adaptability of flange connections to various operating conditions.

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments are briefly introduced below.

[0020] Figure 1 This is a perspective view of a flange connection structure with a seal.

[0021] Figure 2 This is a diagram showing the assembled sealing mechanism in a flange connection structure with a seal.

[0022] Figure 3 This is a partial enlarged view of the first sealing component in a flange connection structure with a seal.

[0023] Figure 4 This is a partial enlarged view of the second sealing assembly in a flange connection structure with a seal.

[0024] The reference numerals in the attached figures are as follows: 1. Connecting flange; 2. Sealing groove; 3. Sealing mechanism; 31. Sealing ring; 32. First sealing assembly; 321. Outer sealing gasket; 322. First conical gasket; 33. Second sealing assembly; 331. Inner sealing gasket; 332. Second conical gasket. Detailed Implementation

[0025] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0026] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0027] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0028] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0029] Example 1 See Figures 1 to 2 This embodiment discloses a flange connection structure with a seal. The core components include a connecting flange 1 and a sealing mechanism 3, and the specific structure is as follows: Connection flange 1: It has an annular sealing groove 2 inside and is connected to the external pipe by a threaded connection. Sealing mechanism 3: Located within the sealing groove 2, it includes the following components: Sealing ring 31: A circular central support member located in the middle of the sealing groove 2; First sealing assembly 32: includes an outer sealing gasket 321 located outside the sealing ring 31. The outer sealing gasket 321 is made of an elastic soft material (such as oil-resistant rubber or PTFE composite material), and the side in contact with the sealing ring 31 has a corrugated structure. The second sealing assembly 33 includes an inner sealing gasket 331 located inside the sealing ring 31. The inner sealing gasket 331 is made of an elastic soft material (such as oil-resistant rubber or PTFE composite material), and the side in contact with the sealing ring 31 has a corrugated structure.

[0030] Working principle of each component in Example 1: The connecting flange 1 serves as the main body of the pipe connection, with an annular sealing groove 2 inside, and is connected to the external pipe using a threaded connection. The threaded fastening generates axial preload, which is transmitted to the entire sealing mechanism 3 within the sealing groove 2, driving the first sealing component 32 and the second sealing component 33 to deform and fill. Simultaneously, its end face mates with the pipe end face, forming the boundary of the sealing gap and providing target space for the directional filling of the sealing material.

[0031] The sealing groove 2 is an annular groove inside the connecting flange, and its size is adapted to the overall contour of the sealing mechanism 3. It provides a precise installation and positioning space for the sealing mechanism 3, ensuring that the first sealing component 32 and the second sealing component 33 are always in the mating area between the flange and the pipe during the tightening process; at the same time, the sidewall of the groove restricts the lateral displacement of the sealing mechanism 3, so that the pre-tightening force is concentrated on the axial deformation of the sealing component.

[0032] The sealing ring 31 is a circular central support component, placed in the middle of the sealing groove 2. The first sealing component 32 and the second sealing component 33 are respectively installed on its outer and inner sides. As the core skeleton of the sealing mechanism 3, it supports and positions the first sealing component 32 and the second sealing component 33, ensuring that the sealing components maintain a stable relative position when tightened. Its rigid structure evenly transmits the axial preload to the outer sealing gasket 321 and the inner sealing gasket 331, avoiding uneven local stress.

[0033] The first sealing assembly 32 includes an outer sealing gasket 321 (a soft material with a corrugated structure). The axial preload causes the outer sealing gasket 321 to compress and deform. Due to the rigid constraint of the pipe end face and the bottom wall of the sealing groove 2 in the axial direction, the outer sealing gasket 321 will further fill the gap between itself and the outer wall of the sealing groove 2, as well as the gap between itself and the outer wall of the sealing ring 31, thereby ensuring the sealing performance on the outside and blocking the path of medium leakage from the outside.

[0034] The second sealing assembly 33 includes an inner sealing gasket 331 (a soft material with a corrugated structure). The axial preload causes the inner sealing gasket 331 to compress and deform. Due to the rigid constraint of the pipe end face and the bottom wall of the sealing groove 2 in the axial direction, the inner sealing gasket 331 will further fill the gap between itself and the inner wall of the sealing groove 2, as well as the gap between itself and the inner wall of the sealing ring 31, thereby ensuring the sealing performance of the inner side and blocking the path of medium leakage from the inner side.

[0035] In this embodiment, it needs to be further explained that during thread tightening, the rotational torque applied by the operator is converted into axial thrust through the thread helix angle (the angle between the thread teeth and the axis): During the threaded engagement process, the flange and the end face of the pipe gradually approach each other, pushing the sealing mechanism 3 to compress axially; this axial thrust is eventually converted into the pre-tightening force inside the sealing mechanism 3, which directly acts on the corrugated structure of the soft sealing gasket, causing it to deform and generate active filling, thereby forming an inner and outer seal.

[0036] In one possible embodiment, the corrugated structure parameters of the outer sealing gasket 321 and the inner sealing gasket 331 include: a corrugation height of 0.8~1.5mm, a spacing of 1.2~2.5mm, a trapezoidal cross-sectional shape, and a side inclination angle of 45°.

[0037] In this embodiment, it should be further explained that the corrugated structural parameters of the outer sealing gasket 321 and the inner sealing gasket 331 (corrugation height 0.8~1.5mm, spacing 1.2~2.5mm, trapezoidal cross section, 45° side inclination angle) are one of the designs to achieve active sealing compensation. Their working principle and impact on the sealing effect are as follows: (1) Corrugation height (0.8~1.5mm) This height range provides a moderate compressible volume for soft gaskets: When the flange is tightened, an axial preload is generated, and the corrugated structure undergoes elastic deformation, with the high degree of compression being converted into a radial flow of material. If the height is too small, the deformation will be insufficient and the radial gap between the flange groove and the sealing ring will not be fully filled; if it is too high, excessive compression will easily cause the gasket to break or lose its elastic recovery ability, affecting the long-term sealing stability.

[0038] (2) Corrugation spacing (1.2~2.5mm) The spacing design ensures that each corrugated unit deforms independently and uniformly. When the spacing is too small, adjacent corrugations squeeze each other, resulting in uneven deformation and insufficient sealing pressure in some areas; when the spacing is too large, the area between corrugations lacks support and is prone to gaps. The appropriate spacing allows for a more even distribution of pressure on the sealing surface, forming a continuous sealing band and preventing leaks.

[0039] (3) Trapezoidal cross section and 45° side inclination angle Trapezoidal cross section: Compared with triangle / semicircle, trapezoid has a more stable structure and a larger contact area, and the top plane can fit tightly with the surface of the sealing ring after compression; 45° Side Inclination Angle: Utilizing the principle of force decomposition, the axial preload is converted into radial thrust (the axial force is decomposed into radial components along the 45° inclined side), guiding the soft material to flow into the radial gap on the outside / inside (such as the outer gasket flowing into the gap between the outer wall of the flange groove and the outer wall of the sealing ring), achieving precise filling.

[0040] These parameters work synergistically to improve sealing reliability in three ways: (1) Directional filling: The material is guided to the weak sealing area (radial gap) at a 45° angle, avoiding the voids caused by the random flow of traditional gasket materials; (2) Uniform pressure distribution: The optimization of corrugation height and spacing makes the contact pressure of the sealing surface more uniform, reducing the risk of local leakage; (3) Adaptability to working conditions: The parameter range is adapted to different working conditions (pressure fluctuations, temperature changes). For example, when the stainless steel spring ring is used to absorb thermal expansion displacement, the corrugated structure can still maintain effective deformation and preload, and maintain long-term sealing stability.

[0041] Example 2 See Figure 3 In one possible embodiment, a first conical gasket 322 is fixedly connected to the top of the side of the outer sealing gasket 321 that contacts the sealing ring 31. When the outer sealing gasket 321 is compressed and deformed, the first conical gasket 322 overlaps with the outer edge of the sealing ring 31 to form an outer radial sealing wall, which further blocks the path of medium leakage from the outside and further improves the sealing performance.

[0042] In one possible embodiment, the first tapered gasket 322 is made of a flexible soft material (such as oil-resistant rubber or PTFE composite material).

[0043] See Figure 4 In one possible embodiment, a second conical gasket 332 is fixedly connected to the top of the side of the inner sealing gasket 331 that contacts the sealing ring 31. When the inner sealing gasket 331 is compressed and deformed, the second conical gasket 332 overlaps with the inner edge of the sealing ring 31 to form an inner radial sealing wall, which further blocks the path of medium leakage from the inside and further improves the sealing performance.

[0044] In one possible embodiment, the second conical gasket 332 is made of a flexible soft material (such as oil-resistant rubber or PTFE composite material).

[0045] In this embodiment, it is necessary to further explain that the tapered gasket is a key reinforcing structure of the sealing assembly, and its working mechanism is closely related to the force transmission and material deformation during the flange tightening process: (1) Structural foundation: Location: Fixed to the top of the side of the inner and outer sealing gaskets that contact the sealing ring 31 (near the inner and outer edges of the sealing ring 31); Materials: Made of elastic soft materials (such as oil-resistant rubber and PTFE composite materials), possessing good deformation capacity and resilience.

[0046] (2) Deformation triggering and directional motion: When the flange generates axial preload through threaded fastening, the force is transmitted to the inner and outer sealing gaskets: The corrugated structure (trapezoidal cross section, 45° side inclination angle) of the inner and outer sealing gaskets decomposes the axial preload into a radial component (a horizontal component along the 45° inclined side). The radial force guides the soft material (including the conical gasket fixed at the top) to flow towards the inner and outer edges of the sealing ring 31; As the gasket continues to compress, the conical gasket gradually comes into contact with the inner and outer edges of the sealing ring 31 due to elastic deformation, eventually achieving a tight overlap.

[0047] (3) Precision of the overlap: The parameters of the corrugated structure (such as height of 0.8~1.5mm and spacing of 1.2~2.5mm) ensure uniform deformation and avoid excessive local compression or excessive gaps in the conical gaskets, so that the overlapping area forms a continuous and stable contact zone.

[0048] The conical gasket provides double protection for the seal on both the inner and outer sides through an "overlap seal" mechanism: (1) Additional radial sealing wall: After overlapping, the conical gasket 322 and the inner and outer edges of the sealing ring 31 form a radial sealing barrier, directly blocking the path of leakage of the medium from the "edge gap between the sealing gasket and the sealing ring 31" (a weak point is easily found in traditional seals).

[0049] (2) Enhanced sealing through synergistic corrugated structure: Combined with the corrugated filling of the sealing gasket (filling the radial gap between the outer wall of the flange groove and the outer wall of the sealing ring 31), a composite sealing system of "radial gap filling + edge overlap sealing" is formed, which greatly improves the redundancy of the seal.

[0050] (3) Adaptability to operating conditions: The properties of elastic and soft materials enable them to adapt to working conditions such as pressure fluctuations and temperature changes: for example, when a pipe expands thermally, the stainless steel spring ring absorbs axial displacement, and the tapered gasket can still maintain the overlapping state through elastic deformation, keeping the preload stable.

[0051] The core difference from traditional sealing methods:

[0052] In summary, the conical gasket design upgrades the traditional "passive bonding" to "active targeted sealing," precisely filling the weak points at the sealing edge. It is one of the key structures in this utility model that realizes the transformation "from passive compression to active compensation."

[0053] In one possible embodiment, the sealing ring 31 is made of stainless steel 304 / 316.

[0054] In one possible embodiment, a positioning groove adapted to the sealing ring 31 is provided on the bottom wall of the sealing groove 2, and the sealing ring 31 is embedded in the positioning groove.

[0055] In this embodiment, it should be further explained that the positioning groove on the bottom wall of the sealing groove 2 is an adaptive structure specifically designed for the sealing ring 31. It achieves precise fixation and functional enhancement of the sealing ring 31 through physical fitting. The core principle is as follows: (1) Precise positioning and structural stability The shape and size of the positioning groove perfectly match the sealing ring 31, and the sealing ring 31, once installed, can restrict radial and circumferential displacement. To prevent the sealing ring 31 from shifting due to pre-tightening force during flange tightening, ensure that it is always centered in the sealing groove 2; Provides a stable support reference for the outer sealing gasket 321 and the inner sealing gasket 331 to prevent gap leakage caused by misalignment of the sealing assembly.

[0056] (2) Uniform preload transmission As the core skeleton of the sealing mechanism, the fixed position of the sealing ring 31 directly affects the distribution of preload force. The fitting structure of the positioning groove ensures that the sealing ring 31 is subjected to uniform force, and the axial preload generated by the flange fastening is evenly transmitted to the inner and outer sealing gaskets 321, avoiding sealing failure caused by uneven local force. The corrugated structure (trapezoidal cross section, 45° inclination) of the sealing gasket ensures that the preload is effectively converted into radial filling force, guiding the soft material to the weak gaps in the seal (such as the radial gap between the flange groove and the sealing ring).

[0057] (3) Enhanced adaptability to working conditions Under complex operating conditions such as pressure fluctuations and temperature changes, this design enhances the structure's resistance to interference. To prevent the sealing ring 31 from shifting due to pipeline vibration or thermal expansion and contraction, and to maintain the relative position stability of the sealing assembly; If a stainless steel spring ring is fitted inside the positioning groove, the stainless steel spring ring can provide reliable support for the sealing ring 31, enabling it to effectively absorb axial displacement, maintain the stability of the sealing gasket preload, and further enhance the long-term sealing reliability.

[0058] This design solves the problems of seal displacement and uneven preload in traditional seals through a triple mechanism of "physical fixation + force transmission optimization + working condition adaptation," and is a key structural support for achieving "active compensation sealing."

[0059] In one possible embodiment, a stainless steel spring ring is provided in the positioning groove. When the pipe expands due to heat, the stainless steel spring ring is compressed to absorb axial displacement, so as to maintain the stability of the preload of the sealing gasket.

[0060] In this embodiment, it is necessary to further explain that the stainless steel spring ring is installed in the positioning groove of the bottom wall of the sealing groove, and its elastic deformation characteristics are used to achieve axial displacement compensation: when the pipeline elongates axially due to temperature changes (such as thermal expansion), the spring ring will compress and deform to absorb the relative axial displacement between the pipeline and the flange; conversely, when the pipeline shrinks due to cold, the spring ring releases the stored energy through elastic recovery to maintain the continuous pre-tightening force on the sealing mechanism 3.

[0061] The positioning groove serves as the mounting base for the spring ring and also houses the sealing ring 31. The spring ring, located at the bottom of the positioning groove, directly supports the sealing ring 31, ensuring that the sealing ring 31 remains centered during displacement compensation and preventing misalignment. The preload of the spring ring is transmitted to the sealing ring 31 and then evenly distributed to the outer sealing gasket 321 and the inner sealing gasket 331. When the pipeline is displaced, the elastic deformation of the spring ring counteracts the effect of the displacement on the preload, so that the sealing gaskets (including corrugated structures and tapered gaskets) always remain in a moderately compressed state, maintaining the effect of directional filling and overlapping sealing.

[0062] Technical effects achieved by stainless steel spring rings: Stable preload: Effectively prevents loss of preload due to thermal expansion and contraction of pipelines, ensuring that the gasket continuously adheres to the sealing surface and avoids leakage; Enhanced adaptability to operating conditions: It can adapt to complex operating conditions such as pressure fluctuations and temperature changes. For example, when the pipeline vibrates or the medium temperature changes, the spring ring can absorb dynamic displacement and maintain the stability of the sealing structure. Long-term reliability improvement: The stainless steel material has strong corrosion resistance and long-lasting elastic recovery performance. Combined with the elastic deformation of the corrugated gasket and the overlapping seal of the tapered gasket, multiple redundancy protections are formed to extend the service life of the sealing structure.

[0063] The above embodiments are merely preferred embodiments of this utility model and should not be construed as limiting the scope of protection of this utility model. Any non-substantial changes and substitutions made by those skilled in the art based on this utility model shall fall within the scope of protection claimed by this utility model.

Claims

1. A flange connection structure with a seal, characterized in that, Includes connecting flange (1) and sealing mechanism (3); The connecting flange (1) has an annular sealing groove (2) inside and is connected to the external pipe by a threaded connection. The sealing mechanism (3) is placed in the sealing groove (2) and includes a sealing ring (31), a first sealing component (32) and a second sealing component (33). The sealing ring (31) is located in the middle of the sealing groove (2); The first sealing assembly (32) includes an outer sealing gasket (321) located outside the sealing ring (31), the outer sealing gasket (321) is made of elastic soft material, and the side in contact with the sealing ring (31) has a corrugated structure; The second sealing assembly (33) includes an inner sealing gasket (331) located inside the sealing ring (31), the inner sealing gasket (331) being made of an elastic soft material and having a corrugated structure on the side in contact with the sealing ring (31).

2. The flange connection structure with sealing according to claim 1, characterized in that, The corrugated structure parameters of the outer sealing gasket (321) and the inner sealing gasket (331) include: corrugation height of 0.8~1.5mm, spacing of 1.2~2.5mm, cross-sectional shape of trapezoid, and side inclination angle of 45°.

3. The flange connection structure with sealing according to claim 1 or 2, characterized in that, The outer sealing gasket (321) is fixedly connected to the top of the side of the sealing ring (31) with a first conical gasket (322). When the outer sealing gasket (321) is compressed and deformed, the first conical gasket (322) overlaps with the outer edge of the sealing ring (31).

4. The flange connection structure with sealing according to claim 3, characterized in that, The first conical gasket (322) is made of an elastic soft material.

5. The flange connection structure with sealing according to claim 1 or 2, characterized in that, The inner sealing gasket (331) is fixedly connected to the top of the side of the sealing ring (31) with a second conical gasket (332). When the inner sealing gasket (331) is compressed and deformed, the second conical gasket (332) overlaps with the inner edge of the sealing ring (31).

6. The flange connection structure with sealing according to claim 5, characterized in that, The second conical gasket (332) is made of a flexible soft material.

7. The flange connection structure with sealing according to claim 1 or 2, characterized in that, The bottom wall of the sealing groove (2) is provided with a positioning groove that is adapted to the sealing ring (31), and the sealing ring (31) is embedded in the positioning groove.

8. The flange connection structure with sealing according to claim 7, characterized in that, The positioning groove is equipped with a stainless steel spring ring.

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