Double-end-face mechanical seal

Abstract

The double-end-face mechanical seal comprises a shaft body, a pump cover and a gland connected to the pump cover, the shaft body is arranged on the pump cover and the gland in a penetrating mode, the pump cover is provided with a static ring and a cavity A, the gland is provided with a movable ring and a cavity B, the static ring abuts against the movable ring, and the cavity A and the cavity B are separated through the static ring and the movable ring. The transmission seat is located on the side, away from the static ring, of the movable ring, a push ring is arranged between the movable ring and the transmission seat, the push ring is connected with the transmission seat through an elastic piece, the push ring can abut against the movable ring, the movable ring is provided with a sealing ring, the shaft body is provided with a blocking piece, the blocking piece is located between the sealing ring and the push ring, and the sealing ring can abut against the blocking piece. The blocking piece is arranged between the sealing ring and the push ring, the sealing ring can be effectively prevented from being driven by the shaft body to move rightwards to press the push ring when the pressure of the cavity A is higher than that of the cavity B, and the problem that the sealing ring is clamped between the movable ring and the push ring to cause sealing failure is solved.

Description

Technical Field

[0001] This application relates to the technical field of mechanical seals, and in particular to a double-end mechanical seal. Background Technology

[0002] Combination Figure 1 and Figure 2 As shown, the existing double-end face seal includes a shaft 1, a pump cover 2, and a pressure cover 3. The shaft 1 passes through the pump cover 2 and the pressure cover 3. The pump cover 2 is provided with a stationary ring 21 and a cavity A 22. The pressure cover 3 is provided with a rotating ring 31 and a cavity B 32. The stationary ring 21 abuts against the rotating ring 31, and the stationary ring 21 and the rotating ring 31 separate the cavity A 22 and the cavity B 32. The pressure cover 3 is provided with a transmission seat 33, which is located on the side of the rotating ring 31 away from the stationary ring 21. A push ring 34 and a spring are provided between the rotating ring 31 and the transmission seat 33. The two ends of the spring are fixedly connected to the rotating ring 31 and the transmission seat 33, respectively. The cooperation of the push ring 34 and the spring makes the rotating ring 31 and the stationary ring 21 abut tightly. The rotating ring 31 is provided with a mounting groove 311, and a sealing ring 4 is provided in the mounting groove 311. The sealing ring 4 is sleeved on the shaft 1. Both the rotating ring 31 and the sealing ring 4 abut against the push ring 34. The sealing ring 4 is used to seal the gap between the rotating ring 31 and the shaft 1.

[0003] In standard applications, the pressure in chamber B must be greater than that in chamber A, i.e., the positive pressure. However, if the pressure in chamber A exceeds that in chamber B due to special circumstances (such as improper operation), the shaft, through friction, causes the sealing ring to shift to the right and press against the push ring. This pushes the push ring away from the contact with the moving ring, causing the sealing ring to become stuck between the end of the moving ring closest to the push ring and the push ring. There is a risk of the sealing ring being extruded, leading to seal failure between the moving ring and the shaft, which needs improvement. Utility Model Content

[0004] The purpose of this application is to provide a double-end mechanical seal to improve the sealing between the rotating ring and the shaft.

[0005] This application provides a double-end mechanical seal with the following technical solution: It includes a shaft, a pump cover, and a gland connected to the pump cover. The shaft passes through the pump cover and the gland. The pump cover has a stationary ring and a cavity A. The gland has a rotating ring and a cavity B. The stationary ring abuts against the rotating ring, and the stationary ring and the rotating ring separate the cavity A and the cavity B. The gland has a transmission seat located on the side of the rotating ring away from the stationary ring. A push ring is provided between the rotating ring and the transmission seat. The push ring is connected to the transmission seat by an elastic element, and the push ring can abut against the rotating ring. The rotating ring has a sealing ring. The shaft has a blocking element located between the sealing ring and the push ring, and the sealing ring can abut against the blocking element.

[0006] By adopting the above technical solution, the blocking component is placed between the sealing ring and the push ring, which effectively prevents the sealing ring from shifting to the right and pressing against the push ring due to the shaft drive when the pressure in cavity A is higher than that in cavity B. This avoids the problem of the sealing ring getting stuck between the moving ring and the push ring, leading to seal failure. This design significantly improves the reliability of the double-end mechanical seal under abnormal operating conditions and ensures stable sealing performance between the moving ring and the shaft.

[0007] Optionally, the blocking member includes a blocking ring plate and a limiting ring plate disposed on the side of the blocking ring plate away from the sealing ring. The limiting ring plate is located between the push ring and the shaft. Both the blocking ring plate and the limiting ring plate are connected to the shaft. The closest distance between the blocking ring plate and the push ring is greater than or equal to the closest distance between the limiting ring plate and the transmission seat.

[0008] By adopting the above technical solution, the blocking ring plate and the limiting ring plate effectively prevent the sealing ring from being squeezed out under abnormal operating conditions. Specifically, the blocking ring plate is located between the sealing ring and the push ring, which can directly prevent the sealing ring from moving excessively towards the push ring, thus preventing the sealing ring from detaching from the sealing position between the rotating ring and the shaft. The limiting ring plate further restricts the movement range of the push ring, ensuring that the push ring does not get too close to the push ring, preventing the push ring from driving the push ring to move, that is, preventing the sealing ring from getting stuck between the rotating ring and the push ring.

[0009] Optionally, a plurality of the blocking elements are connected to the shaft body, and the plurality of the blocking elements are spaced apart around the axis of the shaft body. Each blocking element includes a blocking block and a limiting block disposed on the side of the blocking block away from the sealing ring. The limiting block is located between the push ring and the shaft body, and both the blocking block and the limiting block are connected to the shaft body.

[0010] By adopting the above technical solution, several blocking components are connected to the shaft and spaced apart around the shaft's centerline, effectively increasing the support area of ​​the blocking components for the sealing ring, thereby improving the stability of the sealing ring under abnormal operating conditions. Specifically, the blocking block is located between the sealing ring and the push ring, preventing the sealing ring from being squeezed out when the pressure in cavity A is higher than that in cavity B, thus avoiding seal failure. The limiting block is located between the push ring and the shaft, further limiting the movement range of the push ring and ensuring that the push ring and the moving ring maintain a stable contact state, thereby improving the overall sealing performance.

[0011] Optionally, several of the blocking elements are evenly distributed around the axis of the shaft.

[0012] By adopting the above technical solution, the uniformity of the blocking component around the axis of the shaft ensures that the sealing ring is subjected to consistent constraint force in all directions, further reducing the risk of the sealing ring getting stuck between the moving ring and the push ring, leading to sealing failure.

[0013] Optionally, the limiting block and the shaft are detachably connected via a locking element.

[0014] By adopting the above technical solution, the limit block and the shaft are detachably connected through the locking component, making the installation and removal of the limit block more convenient and facilitating the replacement or maintenance of the limit block.

[0015] Optionally, the locking element is a bolt, the limiting block is provided with a through hole for the threaded end of the bolt to pass through, and the shaft is provided with a threaded groove for threaded engagement with the bolt.

[0016] By adopting the above technical solution, the locking component uses a bolt structure, and through holes are provided on the limiting block and threaded grooves are provided on the shaft, making the connection between the limiting block and the shaft more stable and reliable. The bolt connection method is simple to operate, easy to disassemble and maintain, and can effectively prevent the limiting block from loosening or falling off during operation, thereby ensuring that the blocking component's protection of the sealing ring is always in optimal condition.

[0017] Optionally, the limiting block is provided with a positioning part, and the shaft is provided with a positioning groove for the positioning part to engage. When the positioning part is engaged in the positioning groove, the through hole is aligned with the threaded groove.

[0018] By adopting the above technical solution, the positioning part on the limit block cooperates with the positioning groove on the shaft, ensuring that the limit block is installed in the shaft position accurately and avoiding sealing failure caused by installation deviation. At the same time, when the positioning part is engaged in the positioning groove, the through hole and the threaded groove are aligned, facilitating the quick and accurate connection of bolts, improving assembly efficiency and ensuring the reliability of the connection.

[0019] Optionally, at least two of the sealing rings are disposed on the moving ring.

[0020] By adopting the above technical solution, when the pressure in chamber A is higher than the pressure in chamber B, even if one of the sealing rings fails due to extrusion or other reasons, the other sealing ring can still maintain the sealing effect between the moving ring and the shaft, thereby avoiding the risk of leakage and improving the reliability of the overall structure.

[0021] In summary, this application includes at least one of the following beneficial technical effects:

[0022] 1. The blocking element is set between the sealing ring and the push ring, which can effectively prevent the sealing ring from moving to the right and pressing the push ring when the pressure in cavity A is higher than that in cavity B due to the shaft, thus avoiding the problem of the sealing ring getting stuck between the moving ring and the push ring, which would lead to sealing failure.

[0023] 2. The retaining ring plate is located between the sealing ring and the push ring, and can directly prevent the sealing ring from moving excessively towards the push ring, thus preventing the sealing ring from detaching from the sealing position between the moving ring and the shaft. The limiting ring plate further restricts the movement range of the push ring, ensuring that the push ring does not get too close to the push ring, preventing the push ring from driving the push ring to move, that is, preventing the sealing ring from getting stuck between the moving ring and the push ring. Attached Figure Description

[0024] Figure 1 This is a cross-sectional view of the prior art.

[0025] Figure 2 yes Figure 1 An enlarged view of region A.

[0026] Figure 3 This is a cross-sectional view of Embodiment 1 of this application.

[0027] Figure 4 yes Figure 3 A magnified view of region B.

[0028] Figure 5 This is a cross-sectional view of Embodiment 2 of this application.

[0029] Figure 6 yes Figure 5 A magnified view of region C.

[0030] Figure 7 This is a partial structural schematic diagram of Embodiment 2 of this application.

[0031] Explanation of reference numerals in the attached drawings: 1. Shaft body; 11. Threaded groove; 12. Positioning groove; 2. Pump cover; 21. Stationary ring; 22. Chamber A; 3. Pressure gland; 31. Rotary ring; 311. Mounting groove; 32. Chamber B; 33. Transmission seat; 34. Push ring; 35. Elastic element; 4. Sealing ring; 5. Blocking element; 51. Blocking ring plate; 52. Limiting ring plate; 53. Blocking block; 54. Limiting block; 541. Through hole; 542. Positioning part; 6. Locking element. Detailed Implementation

[0032] The following is in conjunction with the appendix Figure 1 - Appendix Figure 7 This application will be described in further detail.

[0033] This application discloses a double-end mechanical seal.

[0034] Example 1

[0035] Combination Figure 3 and Figure 4As shown, the system includes a shaft 1, a pump cover 2, and a pressure cap 3 detachably connected to the pump cover 2. The shaft 1 passes through the pump cover 2 and the pressure cap 3. The pump cover 2 is provided with a stationary ring 21 and has an A cavity 22. The pressure cap 3 is provided with a moving ring 31 and has a B cavity 32. The stationary ring 21 abuts against the moving ring 31, and the stationary ring 21 and the moving ring 31 separate the A cavity 22 and the B cavity 32. The pressure cap 3 is provided with a transmission seat 33, which is located on the side of the moving ring 31 away from the stationary ring 21. A push ring 34 is provided between the moving ring 31 and the transmission seat 33. The push ring 34 and the transmission seat 33 are connected by several elastic elements 35, which are springs. The two ends of the elastic elements 35 are fixedly connected to the push ring 34 and the transmission seat 33, respectively. The push ring 34 can abut against the moving ring 31. The rotating ring 31 is provided with a sealing ring 4. In other embodiments, there may be multiple sealing rings 4. The inner ring of the rotating ring 31 has a mounting groove 311 for the sealing ring 4 to be engaged. The outer surface of the shaft 1 is provided with a blocking member 5. The blocking member 5 includes a blocking ring plate 51 and a limiting ring plate 52 disposed on the side of the blocking ring plate 51 away from the sealing ring 4. The blocking ring plate 51 and the limiting ring plate 52 are integrally formed and are both fixedly connected to the shaft 1. The blocking ring plate 51 is located in the mounting groove 311, and the sealing ring 4 can abut against the blocking ring plate 51. The limiting ring plate 52 is located between the push ring 34 and the shaft 1. The closest distance between the blocking ring plate 51 and the push ring 34 is greater than or equal to the closest distance between the limiting ring plate 52 and the transmission seat 33. In this embodiment, the closest distance between the blocking ring plate 51 and the push ring 34 is greater than the closest distance between the limiting ring plate 52 and the transmission seat 33.

[0036] The implementation principle of a double-end mechanical seal in this application embodiment is as follows:

[0037] The blocking ring plate 51 is located between the sealing ring 4 and the push ring 34, directly preventing the sealing ring 4 from moving excessively towards the push ring 34, thus avoiding the sealing ring 4 from disengaging from the sealing position between the rotating ring 31 and the shaft 1. The limiting ring plate 52 further restricts the movement range of the push ring 34, ensuring that the push ring 34 does not move excessively towards the push ring 34, preventing the push ring 34 from moving the driving ring 31 plate, that is, preventing the sealing ring 4 from getting stuck between the rotating ring 31 and the push ring 34. This design significantly improves the reliability of the double-end mechanical seal under abnormal operating conditions, ensuring stable sealing performance between the rotating ring 31 and the shaft 1.

[0038] Example 2

[0039] The difference between this embodiment and Embodiment 1 is that, in combination with Figure 5 , Figure 6 and Figure 7As shown, several blocking elements 5 are connected to the shaft body 1, and the blocking elements 5 are evenly spaced around the axis of the shaft body 1. Each blocking element 5 includes a blocking block 53 and a limiting block 54 located on the side of the blocking block 53 away from the sealing ring 4. The limiting block 54 is integrally formed with the blocking block 53 and is located between the push ring 34 and the shaft body 1. Each limiting block 54 is connected to the shaft body 1 by a locking element 6, which is a bolt. The limiting block 54 has a through hole 541 for the threaded end of the bolt to pass through, and the shaft body 1 has a threaded groove 11 for threaded engagement with the bolt. The limiting block 54 is provided with a positioning part 542, which is integrally formed with the limiting block 54. The shaft body 1 has a positioning groove 12 for the positioning part 542 to engage. When the positioning part 542 engages in the positioning groove 12, the through hole 541 aligns with the threaded groove 11.

[0040] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A double-end mechanical seal, comprising a shaft (1), a pump cover (2), and a gland (3) connected to the pump cover (2), wherein the shaft (1) passes through the pump cover (2) and the gland (3), the pump cover (2) is provided with a stationary ring (21) and a cavity A (22), and the gland (3) is provided with a rotating ring (31) and a cavity B (32), wherein the stationary ring (21) abuts against the rotating ring (31), and the stationary ring (21) and the rotating ring (31) seal the cavity A (22) and the cavity B (32). The B cavity (32) is separated, and the pressure cap (3) is provided with a transmission seat (33). The transmission seat (33) is located on the side of the moving ring (31) away from the stationary ring (21). A push ring (34) is provided between the moving ring (31) and the transmission seat (33). The push ring (34) is connected to the transmission seat (33) by an elastic element (35). The push ring (34) can abut against the moving ring (31). The moving ring (31) is provided with a sealing ring (4). The feature is that: The shaft (1) is provided with a blocking member (5), which is located between the sealing ring (4) and the push ring (34), and the sealing ring (4) can abut against the blocking member (5).

2. The double-end mechanical seal according to claim 1, characterized in that: The blocking member (5) includes a blocking ring plate (51) and a limiting ring plate (52) disposed on the side of the blocking ring plate (51) away from the sealing ring (4). The limiting ring plate (52) is located between the push ring (34) and the shaft (1). Both the blocking ring plate (51) and the limiting ring plate (52) are connected to the shaft (1). The closest distance between the blocking ring plate (51) and the push ring (34) is greater than or equal to the closest distance between the limiting ring plate (52) and the transmission seat (33).

3. The double-end mechanical seal according to claim 1, characterized in that: A plurality of the aforementioned blocking members (5) are connected to the shaft (1). The plurality of the aforementioned blocking members (5) are spaced apart around the axis of the shaft (1). The blocking member (5) includes a blocking block (53) and a limiting block (54) disposed on the side of the blocking block (53) away from the sealing ring (4). The limiting block (54) is located between the push ring (34) and the shaft (1). Both the blocking block (53) and the limiting block (54) are connected to the shaft (1).

4. The double-end mechanical seal according to claim 3, characterized in that: Several of the blocking elements (5) are evenly distributed around the axis of the shaft (1).

5. The double-end mechanical seal according to claim 3, characterized in that: The limiting block (54) and the shaft (1) are detachably connected by a locking member (6).

6. The double-end mechanical seal according to claim 5, characterized in that: The locking element (6) is a bolt, the limiting block (54) is provided with a through hole (541) for the threaded end of the bolt to pass through, and the shaft (1) is provided with a threaded groove (11) for threaded engagement with the bolt.

7. The double-end mechanical seal according to claim 6, characterized in that: The limiting block (54) is provided with a positioning part (542), and the shaft (1) is provided with a positioning groove (12) for the positioning part (542) to be engaged. When the positioning part (542) is engaged in the positioning groove (12), the through hole (541) is aligned with the threaded groove (11).

8. The double-end mechanical seal according to claim 1, characterized in that: At least two of the sealing rings (4) are disposed on the moving ring (31).

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