Floating dam foil end face gas film seal structure with forced cooling function

Abstract

This invention discloses a floating dam foil end-face air film sealing structure with forced cooling function, including a stationary ring seat and a sealing dam located on the stationary ring seat. The sealing dam is housed in a receiving groove opened in the stationary ring seat, and includes a primary dam body and a secondary dam body. The primary dam body is located on the outer side; the outer circumferential surface of the primary dam body is provided with external threads, and the secondary dam body has a connecting groove with internal threads. The primary dam body is threadedly connected to the receiving groove, and a coil spring is connected between the bottom of the primary dam body and the bottom of the connecting groove; a columnar spring is embedded between the bottom of the secondary dam body and the bottom of the receiving groove. Through the floating design of the two-stage sealing dam, the spring of the floating sealing dam will compress when encountering a large impact. The stationary ring area relies on the foil and the floating sealing dam to jointly bear the impact and friction, extending the sealing life and reducing maintenance costs. The threaded connection between the primary and secondary dam bodies reduces wear on the floating dam during start-up and shutdown. In addition, by introducing cooling gas into the air inlet groove opened on the outer circumferential wall of the stationary ring seat, forced cooling of the foil end face can be achieved, reducing the adverse effects of high temperature.

Description

Technical Field

[0001] This invention relates to the field of mechanical seal technology, specifically to a floating dam foil end face air film sealing structure with forced cooling function. Background Technology

[0002] End-face gas film seals, also known as dry gas seals, are a new type of mechanical seal. Currently, dry gas seals are widely used in the shaft end seals of rotating machinery, such as compressors, pumps, reactors, and fans, due to their significant performance advantages, including low leakage, low power consumption, and long service life. With the rapid development of the petrochemical and aerospace industries, there is a growing demand for dry gas seals to operate at higher parameters (such as high speed, high temperature, and high pressure), while also exhibiting greater stability, reliability, and longer service life.

[0003] Existing dry gas sealing technologies often use hard and brittle materials, which are easily broken by impacts under high-speed conditions. Dry gas sealing devices operate at the micrometer level, and when subjected to larger impacts, the sealing end face will wear and change its groove shape, easily leading to seal failure. Summary of the Invention

[0004] The purpose of this invention is to provide a floating dam foil end face air film sealing structure with forced cooling function to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a floating dam foil end face air film sealing structure with forced cooling function, including a stationary ring seat and a sealing dam located on the stationary ring seat; The sealed dam is housed in the receiving groove opened in the static ring seat. The sealed dam includes a primary dam body and a secondary dam body. The primary dam body and the secondary dam body are installed on top of each other, with the primary dam body located on the outer side; The outer circumference of the first-level dam body is provided with external threads, and the second-level dam body is provided with a connecting groove with internal threads. The first-level dam body is threadedly connected to the receiving groove, and a coil spring is connected between the bottom of the first-level dam body and the bottom of the connecting groove. The circumferential rotation of the secondary dam body is limited by the static ring seat, and a columnar spring is embedded between the bottom of the secondary dam body and the bottom of the receiving groove.

[0006] In a further embodiment, a vertical slider that protrudes outward along the radial direction is provided on the peripheral wall of the secondary dam body, and a vertical groove that is concave in the radial direction is provided on the groove wall of the accommodating groove on the stationary ring seat. The slider and the groove are slidably connected, so that the secondary dam body can slide up and down vertically, and the circumferential rotational movement is limited.

[0007] In a further embodiment, guide posts are installed at the bottom of the secondary dam body and the end face of the accommodating groove bottom. The guide posts installed opposite each other are inserted into the two ends of the cylindrical spring for guiding the cylindrical spring when it is compressed and released. The cylindrical spring is arranged in a ring array at the bottom of the secondary dam body.

[0008] In a further embodiment, the coil spring is located at the bottom of the primary dam body. One end of the coil spring is fixed to the bottom surface of the primary dam body, and the other end is fixed to the bottom surface of the receiving groove. When the primary dam body is driven by the impact of the moving ring to rotate, it compresses the coil spring. After being compressed, the coil spring resets and transmits torque to the primary dam body, so that the primary dam body resets.

[0009] In a further embodiment, a wave-shaped foil is provided on the end face of the stationary ring seat, and a top foil is covered on the outside of the wave-shaped foil.

[0010] In a further embodiment, an air cavity is provided at the bottom of the stationary ring seat, and an air passage is connected to the upper part of the air cavity. The air passage passes through the end face of the stationary ring seat, and an air hole is formed on the end face of the stationary ring seat. The air hole is located at the bottom of the corrugated foil. A stationary ring sealing block is installed at the bottom of the air cavity. An air inlet groove is provided on the outer peripheral wall of the stationary ring seat, and the air inlet groove is connected to the air cavity.

[0011] In a further embodiment, the pores are arranged radially in sequence and distributed in a ring array.

[0012] In a further embodiment, sealing rings are embedded in the outer periphery of the primary dam body, the outer periphery of the secondary dam body, and the outer periphery of the static ring seat sealing block.

[0013] Compared with the prior art, the beneficial effects of the present invention are: This invention relates to a floating dam foil end-face air film sealing structure with forced cooling function. Through the floating design of the two-stage sealing dam, the spring of the floating sealing dam will compress when encountering a large impact. The static ring area relies on the foil and the floating sealing dam to jointly bear the impact and friction, extending the seal life and reducing maintenance costs. The primary and secondary dam bodies are connected by threads, which can reduce wear on the floating dam during start-up and shutdown.

[0014] In addition, by introducing cooling gas into the air inlet slot on the outer peripheral wall of the stationary ring seat, the end face of the foil can be forcibly cooled, reducing the adverse effects of high temperature. Attached Figure Description

[0015] Figure 1 This is a structural diagram of the present invention in its assembled state; Figure 2 for Figure 1 A sectional view; Figure 3 This is a schematic diagram of the static ring seat structure of the present invention; Figure 4 This is a schematic diagram of the secondary dam structure of the present invention; Figure 5 This is a schematic diagram of the assembly structure of the primary and secondary dam bodies of the present invention.

[0016] In the diagram: 1. Stationary ring seat; 10. Stationary ring sealing block; 11. Air inlet groove; 12. Air chamber; 13. Air passage; 14. Air hole; 15. Slide groove; 16. Receiving groove; 2. Top foil; 3. Corrugated foil; 4. Primary dam body; 41. Coil spring; 5. Secondary dam body; 51. Connecting groove; 52. Columnar spring; 53. Sliding block. Detailed Implementation

[0017] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] This embodiment provides a floating dam foil end face air film sealing structure with forced cooling function, referring to... Figure 1 as well as Figure 2 As shown, it includes a stationary ring seat 1 and a sealing dam located on the stationary ring seat 1; The sealed dam is housed in the receiving groove 16 opened in the static ring seat 1. The sealed dam includes a primary dam body 4 and a secondary dam body 5. The first-stage dam body 4 and the second-stage dam body 5 are installed on top of each other, with the first-stage dam body 4 located on the outside. During installation, the first-stage dam body 4 is installed opposite to the dynamic ring. The outer circumferential surface of the primary dam body 4 is provided with external threads, and the secondary dam body 5 is provided with a connecting groove 51 with internal threads. The primary dam body 4 is threadedly connected to the connecting groove 51, and a coil spring 41 is connected between the bottom of the primary dam body 4 and the bottom of the connecting groove 51; see reference. Figure 4 as well as Figure 5 As shown, the coil spring 41 is located at the bottom of the primary dam body 4. One end of the coil spring 41 is fixed to the bottom surface of the primary dam body 4, and the other end is fixed to the bottom surface of the connecting groove 51. When the primary dam body 4 is driven to rotate by the impact of the moving ring, it compresses the coil spring 41. After being compressed, the coil spring 41 resets and transmits torque to the primary dam body 4, so that the primary dam body 4 resets.

[0019] The circumferential rotation of the secondary dam body 5 is limited by the static ring seat 1, referring to... Figure 3 as well as Figure 4 As shown, a vertical slider 53 protruding outward along the radial direction is provided on the peripheral wall of the secondary dam body 5, and a vertical groove 15 concave in the radial direction is provided on the groove wall of the receiving groove 16 on the stationary ring seat 1. The slider 53 is slidably connected to the groove 15, so that the secondary dam body 5 can slide up and down vertically, and the circumferential rotational movement is limited.

[0020] A cylindrical spring 52 is embedded between the bottom of the secondary dam body and the bottom of the receiving trough 16, as shown in the reference. Figure 3 as well as Figure 4 As shown, guide columns are installed at the bottom of the secondary dam body 5 and the end face of the bottom of the receiving groove 16. The guide columns installed opposite each other are inserted into the two ends of the column spring 52 to guide the column spring 52 when it is compressed and released. The column spring 52 is arranged in a ring at the bottom of the secondary dam body 5.

[0021] When the rotating ring and stationary ring are subjected to a large impact, or during the start-up and stop phases of the dry gas sealing device, the primary dam body 4 simultaneously bears axial torque and torque. The axial torque is transmitted to the secondary dam body 5, compressing the cylindrical spring 52 to achieve floating buffering. The torque transmitted by the rotating ring causes the primary dam body 4 to rotate relative to the secondary dam body 5, and the secondary dam body 5 retracts under the action of the thread to avoid continuous contact with the rotating ring and thus prevent wear. After stabilization, the coil spring 41 assists the primary dam body 4 in resetting.

[0022] Based on the above, this embodiment also proposes a forced cooling scheme.

[0023] Reference Figure 1 , Figure 2 as well as Figure 3 As shown, a corrugated foil 3 is provided on the end face of the stationary ring seat 1, and a top foil 2 covers the outer side of the corrugated foil 3; an air cavity 12 is formed at the bottom of the stationary ring seat 1, and an air passage 13 is connected to the upper part of the air cavity 12. The air passage 13 penetrates the end face of the stationary ring seat 1, and an air hole 14 is formed on the end face of the stationary ring seat 1. The air hole 14 is located at the bottom of the corrugated foil 3. A stationary ring sealing block 10 is installed at the bottom of the air cavity 12, and an air inlet groove 11 is formed on the outer peripheral wall of the stationary ring seat 1, which communicates with the air cavity 12. (Refer to...) Figure 3 As shown, the pores 14 are arranged radially in sequence and distributed in a ring array.

[0024] Forced cooling gas is introduced through the air inlet slot 11, allowing the foil to adapt to high rotational speeds and preventing severe expansion and deformation that could lead to seal failure. The forced cooling gas also prevents the temperature of the entire stationary ring from becoming excessively high, preventing the floating dam device from failing its structural expansion and contraction function due to thermal expansion. The high-speed forced gas introduction also increases the foil's support performance. The corrugated foil 3 allows the forced cooling gas beneath the foil to rotate with the moving ring, achieving highly efficient cooling.

[0025] It is worth mentioning that, in order to improve the sealing effect, sealing rings are embedded on the outer periphery of the first-stage dam body 4, the outer periphery of the second-stage dam body 5, and the outer periphery of the static ring seat sealing block 10. That is, at points a, b, c, and d in the figure.

[0026] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A floating dam foil end face air film sealing structure with forced cooling function, comprising a stationary ring seat (1) and a sealing dam located on the stationary ring seat (1); The sealed dam is housed in the receiving groove (16) opened in the static ring seat (1). The sealed dam includes a primary dam body (4) and a secondary dam body (5). The first-stage dam body (4) and the second-stage dam body (5) are installed on top of each other, with the first-stage dam body (4) located on the outside; The outer circumference of the first-level dam body (4) is provided with external threads, and the second-level dam body (5) is provided with a connecting groove (51) with internal threads. The first-level dam body (4) is threadedly connected to the connecting groove (51), and a coil spring (41) is connected between the bottom of the first-level dam body (4) and the bottom of the connecting groove (51). The coil spring (41) is located at the bottom of the first-stage dam body (4). One end of the coil spring (41) is fixed to the bottom surface of the first-stage dam body (4), and the other end is fixed to the bottom surface of the connecting groove (51). When the first-stage dam body (4) is driven by the impact of the moving ring to rotate, the coil spring (41) is compressed. After the coil spring (41) is compressed, it resets and transmits torque to the first-stage dam body (4), so that the first-stage dam body (4) is reset. The circumferential rotation of the secondary dam body (5) is limited by the static ring seat (1), and a columnar spring (52) is embedded between the bottom of the secondary dam body and the bottom of the receiving groove (16).

2. The floating dam foil end face air film sealing structure with forced cooling function according to claim 1, characterized in that: The secondary dam body (5) is provided with a vertical slider (53) that protrudes outward along the radial direction on the periphery wall. The groove wall of the receiving groove (16) on the static ring seat (1) is provided with a vertical sliding groove (15) that is concave in the radial direction. The slider (53) and the sliding groove (15) are slidably connected, so that the secondary dam body (5) can slide up and down vertically, and the circumferential rotational movement is limited.

3. The floating dam foil end face air film sealing structure with forced cooling function according to claim 1, characterized in that: Guide columns are installed at the bottom of the secondary dam body (5) and the end face of the bottom of the receiving groove (16). The guide columns installed opposite each other are inserted into the two ends of the column spring (52) for guiding the column spring (52) when it is compressed and released. The column spring (52) is arranged in a ring at the bottom of the secondary dam body (5).

4. The floating dam foil end face air film sealing structure with forced cooling function according to claim 1, characterized in that: The end face of the stationary ring seat (1) is provided with a wave foil (3), and the outer side of the wave foil (3) is covered with a top foil (2).

5. The floating dam foil end face air film sealing structure with forced cooling function according to claim 4, characterized in that: The bottom of the stationary ring seat (1) is provided with an air chamber (12), and the upper part of the air chamber (12) is connected to an air passage (13). The air passage (13) passes through the end face of the stationary ring seat (1), and the end face of the stationary ring seat (1) forms an air hole (14). The air hole (14) is located at the bottom of the corrugated foil (3). The bottom of the air chamber (12) is equipped with a stationary ring sealing block (10). An air inlet groove (11) is provided on the outer peripheral wall of the stationary ring seat (1), and the air inlet groove (11) is connected to the air chamber (12).

6. The floating dam foil end face air film sealing structure with forced cooling function according to claim 5, characterized in that: The pores (14) are arranged radially in sequence and distributed in a ring array.

7. The floating dam foil end face air film sealing structure with forced cooling function according to claim 1, characterized in that: Sealing rings are embedded in the outer periphery of the first-level dam body (4), the outer periphery of the second-level dam body (5), and the outer periphery of the static ring seat sealing block (10).

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