A new combined seal structure

Abstract

This utility model discloses a novel combined sealing structure, including a sealing ring, a water-absorbing and expandable expansion member, and a sealing ring. The sum of the radial thickness of the sealing ring and the linear diameter of the sealing ring is greater than the distance from the bottom of the sealing groove to the first sealing member. The expansion member is located on the inner side near the sealing position. This combined sealing structure has two states: an initial state and a sealed state. In the initial state, the sealing ring, sealing ring, and expansion member are arranged along the axial direction of the second sealing member, with the sealing ring located between the sealing ring and the expansion member. After the expansion member expands upon contact with water, it compresses the sealing ring, causing the sealing ring to be located inside the sealing ring and supporting it, thus transforming the initial state into the sealed state. In the sealed state, the sealing ring and sealing ring are arranged radially. This utility model avoids interference fits and will not damage or twist the sealing ring, fundamentally overcoming the problems of traditional combined sealing installations.

Description

Technical Field

[0001] This utility model relates to the field of sealing, and in particular to a novel combined sealing structure. Background Technology

[0002] Common combination seals typically consist of a main sealing ring and an elastomer (such as Step seals and Glyd rings). The main sealing ring is primarily made of polytetrafluoroethylene (PTFE) or polyurethane, while the elastomer is mainly made of rubber. This type of seal is often referred to as a compression seal. It achieves the sealing effect between the sealing ring and the metal surface through interference fit, utilizing the supporting force of the elastomer (O-ring) after compression. It can also compensate for wear of the sealing ring.

[0003] Currently, the turbine ball valve structure in large hydroelectric generators uses a combination seal consisting of polyurethane sealing rings and rubber O-rings, such as... Figure 1 As shown. In the sealing installation of small equipment, this combination seal has the advantages of simple installation and reliable sealing. However, for large equipment such as ball valves, this interference fit often inevitably leads to significant problems: When installing a large sealing assembly with an interference fit, because it cannot be slowly inserted by human "feel," mechanical hoisting can easily damage the sealing lip or cause the sealing strip to twist. Furthermore, since the sealing strip has already filled the sealing groove, this damage is not easily detected during leak testing, and leaks often only appear after the unit has been running for a period of time.

[0004] For many years, the solutions to this problem have been to improve the contact surface and insertion angle of the sealing ring and the insertion component, or to increase the material strength of the sealing ring, but none of these solutions can fundamentally solve the problem. Utility Model Content

[0005] The purpose of this utility model is to provide a novel combined sealing structure that addresses the aforementioned problems, avoids interference fit, and does not damage or twist the sealing ring, thus fundamentally overcoming the problems of traditional combined sealing installation.

[0006] The technical solution adopted by this utility model is as follows: A combined sealing structure for a water turbine ball valve, installed between a first sealing element and a second sealing element, located in a sealing groove on the second sealing element, includes a sealing ring, an expansion element capable of expanding by absorbing water, and a sealing ring, wherein the sum of the radial thickness of the sealing ring and the linear diameter of the sealing ring is greater than the distance from the bottom of the sealing groove to the first sealing element; the expansion element is located near the inner side of the sealing position; this combined sealing structure has two states: an initial state and a sealed state; wherein: In the initial state, the sealing ring, sealing ring and expansion member are arranged along the axial direction of the second seal, and the sealing ring is located between the sealing ring and the expansion member; When the expansion component expands upon contact with water, it compresses the sealing ring, causing the sealing ring to be positioned inside the sealing ring and supporting it, thus transforming the initial state into a sealed state; in the sealed state, the sealing ring and sealing ring are arranged radially.

[0007] Furthermore, in the initial state, the sum of the axial width of the sealing ring, the wire diameter of the sealing ring, and the axial width of the expansion element before expansion is greater than the axial width of the sealing groove.

[0008] Furthermore, a chamfer is provided on the side of the sealing ring near the sealing ring, and in the initial state, the chamfer is located on the outer arc of the sealing ring.

[0009] Furthermore, the sealing ring has an "L" shaped cross-section; in the initial state, one side of the sealing ring is in contact with the bottom of the sealing groove; the other side of the sealing ring is used to fit tightly against the first sealing element and the sealing ring.

[0010] Furthermore, the radial thickness of the sealing ring and the diameter of the sealing ring are both smaller than the distance from the bottom of the sealing groove to the first sealing element.

[0011] Furthermore, the surface of the sealing ring that contacts the first sealing element is configured to be wavy.

[0012] Furthermore, the sum of the axial dimension of the fully expanded component and the axial dimension of the sealing ring is not less than the axial dimension of the sealing groove.

[0013] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are: 1. This utility model uses an expansion component to compress the sealing ring, so that the sealing ring and the sealing ring work together to complete the combined seal between the first sealing component and the second sealing component. This does not damage or twist the sealing ring at all, and fundamentally overcomes the problems of traditional combined seal installation. 2. This utility model adds an expansion component, which is installed on the inner side near the sealing position. It can continuously contact the water inside the sealing position and maintain an expanded state, thereby making the entire sealing space more compact. The sealing stability of the sealing ring and sealing ring combination is better, and it effectively prevents harmful phenomena such as torsion and slippage during the sliding process. Attached Figure Description

[0014] This utility model will be described by way of example and with reference to the accompanying drawings, wherein: Figure 1 A schematic diagram of an existing combined sealing structure; Figure 2 This is a schematic diagram of the combined seal disclosed in this utility model in its initial state; Figure 3 This is a schematic diagram of the combined seal disclosed in this utility model in the sealed state; The markings in the diagram are: 1-first seal; 2-second seal; 21-sealing groove; 3-sealing ring; 31-chamfer; 4-sealing ring; 5-expansion element. Detailed Implementation

[0015] In the description of this specification, it should be noted that if terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," or "outer" appear to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use, they are only for the convenience of describing this specification and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this specification.

[0016] Furthermore, the use of terms such as "horizontal" or "vertical" in this specification does not imply that the component must be absolutely horizontal or suspended, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0017] In the description of this specification, it should also be noted that, unless otherwise expressly specified and limited, the terms “set up,” “install,” “connect,” and “link” should be interpreted broadly. For example, a link can be a fixed link, a detachable link, or an integral link; it can be a mechanical link or an electrical link; it can be a direct link or an indirect link through an intermediate medium; it can be a connection within two components.

[0018] Example 1 like Figures 2-3 As shown, a novel combined sealing structure is installed between a first sealing element 1 and a second sealing element 2, located within a sealing groove 21 on the second sealing element 2, for sealing the gap between the first sealing element 1 and the second sealing element 2. Taking a water turbine ball valve as an example, the cylinder body serves as the first sealing element 1, and the metal sealing ring serves as the second sealing element 2. This combined sealing structure includes a sealing ring 3, an expansion element 5 that can expand upon absorbing water, and a sealing ring 4. The sum of the radial thickness of the sealing ring 3 and the linear diameter of the sealing ring 4 is greater than the distance from the bottom of the sealing groove 21 to the first sealing element 1. The expansion element 5 is located on the inner side near the sealing position, such as the inner side of a water turbine ball valve. This combined sealing structure has two states: an initial state and a sealed state. In the initial state, the sealing ring 3, the sealing ring 4, and the expansion member 5 are arranged along the axial direction of the second sealing member 2, and the sealing ring 4 is located between the sealing ring 3 and the expansion member 5; When the expansion component 5 expands upon contact with water, it compresses the sealing ring 4, causing the sealing ring 4 to be located inside the sealing ring 3 and support the sealing ring 3, thus changing the initial state into a sealed state; in the sealed state, the sealing ring 3 and the sealing ring 4 are arranged radially.

[0019] In this embodiment, the main principle is to utilize the expansion member 5 to expand upon contact with water, pushing the sealing ring 4 so that the sealing ring 4 and the sealing ring 3 are located radially on the same cross section. This creates a clamping force between the sealing ring 4 and the bottom of the sealing groove 21, between the sealing ring 4 and the sealing ring 3, and between the sealing ring 3 and the first sealing member 1, achieving a combined seal between the first sealing member 1 and the second sealing member 2. This is different from existing sealing methods described in the background art, such as... Figure 1 As shown, the sealing ring 3 and sealing ring 4 are only interlocked between the first sealing element 1 and the second sealing element 2 and installed in the sealing groove 21 of the second sealing element 2. The combined sealing structure disclosed in this specification uses the expansion member 5 to squeeze the sealing ring 4, so that the sealing ring 4 cooperates with the sealing ring 3 to complete the combined seal between the first sealing element 1 and the second sealing element 2. It will not damage or twist the sealing ring 3 at all, and fundamentally overcomes the problems of traditional combined seal installation.

[0020] It should be noted that limiting "the sum of the radial thickness of the sealing ring 3 and the diameter of the sealing ring 4 to be greater than the distance from the bottom of the sealing groove 21 to the first sealing element 1" is to ensure that when the sealing ring 3 and the sealing ring 4 are in a sealed state (arranged radially), there is a clamping force between the sealing ring 4 and the bottom of the sealing groove 21, between the sealing ring 4 and the sealing ring 3, and between the sealing ring 3 and the first sealing element 1. This is the basis for achieving the combined seal. Furthermore, based on this dimensional constraint, it can be ensured that when the sealing ring 3 contacts the first sealing element 1 and there is a clamping force, the sealing ring 4 will undergo elastic deformation. The resulting elastic force serves two purposes: firstly, it acts as a squeezing force to push the sealing ring 3, keeping the sealing ring 3 pressed against the first sealing element 1, and also sealing the contact surface between the sealing ring 3 and the sealing ring 4; secondly, it acts as a force to press the bottom of the sealing groove 21, thus sealing the sealing ring 4 with the sealing groove 21.

[0021] In this embodiment, the expansion member 5 is installed on the inner side near the sealing position, which can continuously contact the water inside the sealing position and maintain the expansion state, thereby making the entire sealing space more compact. The sealing stability of the sealing ring 3 and sealing ring 4 combined is better, effectively preventing harmful phenomena such as torsion and slippage during the sliding process.

[0022] It should be noted that the expansion member 5 can be made of polyurethane.

[0023] In this embodiment, the shape of the expansion member 5 is also annular, but the cross-section can be rectangular or L-shaped.

[0024] Example 2 Based on Example 1, further feasible implementation methods are proposed.

[0025] In one feasible implementation, in the initial state, the sum of the axial width of the sealing ring 3, the wire diameter of the sealing ring 4, and the axial width of the expansion member 5 before expansion is greater than the axial width of the sealing groove 21. Due to this dimensional constraint, in the initial state, at least two components will have overlapping parts. In this implementation, since the sealing ring 4 needs to enter the interior of the sealing ring 3, the sealing ring 3, the sealing ring 4, and the expansion member 5 can be installed into the sealing groove 21 by having a partial radial overlap between the sealing ring 3 and the sealing ring 4. This dimensional constraint ensures that the sealing ring 4 can enter the interior of the sealing ring 3, effectively avoiding interference.

[0026] In one feasible implementation, a chamfer 31 is provided on the side of the sealing ring 3 near the sealing ring 4. In the initial state, the chamfer 31 is located on the outer arc of the sealing ring 4, and the sealing ring 4 is guided into the sealing ring 3 by the chamfer 31.

[0027] In one feasible implementation, the sealing ring 3 has an "L" shaped cross-section. For ease of explanation, the "L" shaped sealing ring 3 has a vertical arm and a horizontal arm. In the initial state, the vertical arm of the sealing ring 3 contacts the bottom of the sealing groove 21. The other side of the sealing ring 3 is used to fit tightly against the first sealing element 1 and the sealing ring 4. By having the vertical arm abut against the inner wall of the sealing groove 21 and supporting the entire sealing ring 3 in the initial state, and with the sealing ring 4 and the sealing ring 3 having a radial overlap, the position of the sealing ring 3 is stabilized, ensuring that when the sealing ring 4 enters the interior of the sealing ring 3, it can counteract the axial pushing force on the sealing ring 3, so that the sealing ring 3 will not tilt when subjected to axial pushing force. The horizontal arm mainly plays a sealing role after the sealing ring 4 enters the interior of the sealing ring 3.

[0028] In one feasible implementation, the radial thickness of the sealing ring 3 and the wire diameter of the sealing ring 4 are both smaller than the distance from the bottom of the sealing groove 21 to the first sealing element 1, so that the sealing ring 3 and the sealing ring 4 do not need to be interference-fitted when installed in the sealing groove 21, thereby simplifying the installation operation.

[0029] In one feasible implementation, the surface of the sealing ring 3 that contacts the first sealing element 1 is set in a wave shape, and each protruding wave crest can form a seal with the first sealing element 1, thereby achieving multiple seals and increasing the sealing effect.

[0030] In one feasible implementation, the sum of the axial dimension of the fully expanded expansion member 5 and the axial dimension of the sealing ring 3 is not less than the axial dimension of the sealing groove 21, ensuring that the expansion member 5 can completely push the sealing ring 4 into the sealing ring 3.

[0031] In summary, when this combined sealing structure seals the gap between the first sealing element 1 and the second sealing element 2, its sealing process includes the following steps: S1: Insert the sealing ring 3, sealing ring 4 and expansion member 5 into the sealing groove 21. At this time, there is a gap between the sealing ring 3, sealing ring 4 and expansion member 5 and the first sealing member 1. S2: Water inside the sealing position enters the sealing groove 21 from the gap between the second sealing element 2 and the first sealing element 1, and the expansion element 5 absorbs water and expands. S3: During the expansion process of the expansion member 5, the sealing ring 4 is gradually pushed. After being pushed, the sealing ring 4 gradually enters the sealing ring 3, supporting the sealing ring 3, causing the sealing ring 3 to expand outward, gradually approaching and squeezing the first sealing member 1, until the sealing ring 4 is completely inside the sealing ring 3. At this time, there is a pressing force between the sealing ring 4 and the bottom of the sealing groove 21, between the sealing ring 4 and the sealing ring 3, and between the sealing ring 3 and the first sealing member 1, achieving a sealing state and completing the sealing of the turbine ball valve.

[0032] This invention is not limited to the specific embodiments described above. This invention extends to any new feature or combination disclosed in this specification, as well as any new method or process step or combination disclosed herein.

Claims

1. A novel combined sealing structure, characterized in that: Installed between the first seal (1) and the second seal (2), located in the sealing groove (21) on the second seal (2), including a sealing ring (3), an expansion member (5) that can expand by absorbing water, and a sealing ring (4), wherein the sum of the radial thickness of the sealing ring (3) and the linear diameter of the sealing ring (4) is greater than the distance from the bottom of the sealing groove (21) to the first seal (1); the expansion member (5) is located near the inner side of the sealing position; the combined sealing structure has two states: an initial state and a sealed state; wherein: In the initial state, the sealing ring (3), the sealing ring (4) and the expansion member (5) are arranged along the axial direction of the second sealing member (2), and the sealing ring (4) is located between the sealing ring (3) and the expansion member (5); When the expansion component (5) expands upon contact with water, it squeezes the sealing ring (4), causing the sealing ring (4) to be located inside the sealing ring (3) and support the sealing ring (3), thus changing the initial state to a sealed state; in the sealed state, the sealing ring (3) and the sealing ring (4) are arranged radially.

2. The novel combined sealing structure according to claim 1, characterized in that: In the initial state, the sum of the axial width of the sealing ring (3), the wire diameter of the sealing ring (4), and the axial width of the expansion member (5) before expansion is greater than the axial width of the sealing groove (21).

3. The novel combined sealing structure according to claim 1, characterized in that: A chamfer (31) is provided on the side of the sealing ring (3) near the sealing ring (4). In the initial state, the chamfer (31) is located on the outer arc of the sealing ring (4).

4. The novel combined sealing structure according to claim 1, characterized in that: The sealing ring (3) has an "L" shaped cross section; in the initial state, one side of the sealing ring (3) is in contact with the bottom of the sealing groove (21); the other side of the sealing ring (3) is used to fit tightly with the first sealing element (1) and the sealing ring (4).

5. The novel combined sealing structure according to claim 4, characterized in that: The radial thickness of the sealing ring (3) and the wire diameter of the sealing ring (4) are both smaller than the distance from the bottom of the sealing groove (21) to the first sealing element (1).

6. The novel combined sealing structure according to claim 1, characterized in that: The surface of the sealing ring (3) that contacts the first sealing element (1) is configured to be wavy.

7. The novel combined sealing structure according to claim 1, characterized in that: The sum of the axial dimension of the fully expanded expansion member (5) and the axial dimension of the sealing ring (3) is not less than the axial dimension of the sealing groove (21).

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