Shaft end force balancing structure

Abstract

The utility model discloses a shaft end force balancing structure which comprises a pump body, a first pump cover, a second pump cover, an impeller, a driving part, a first mechanical seal, a second mechanical seal, a first flushing pipeline and a second flushing pipeline. A first mechanical seal is connected between the driving piece and the impeller; the second output end of the driving part is connected with the second mechanical seal; a first vent hole is formed in the first pump cover and communicates with the first mechanical seal; a second vent hole is formed in the second pump cover and is communicated with the second mechanical seal; one end of the first flushing pipeline is communicated with the first vent hole, and the other end is communicated with the second vent hole; one end of the second flushing pipeline communicates with the second vent hole, and the other end of the second flushing pipeline communicates with the liquid inlet. The technical effects of balancing shaft end stress and reducing shaft end force generated by the main shaft are achieved, vibration and noise can be reduced, the stability of mechanical equipment is improved, and the service life of the mechanical equipment is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of centrifugal pumps, and in particular to a structure for balancing shaft end forces. Background Art

[0002] As a widely used fluid conveying equipment, centrifugal pumps transfer mechanical energy to fluids through rotating impellers, so that fluids gain pressure energy and kinetic energy, thereby achieving liquid transportation. Centrifugal pumps are usually composed of key components such as pump body, impeller, shaft, motor, etc. They have the advantages of simple structure, easy operation, uniform flow, etc., and are widely used in chemical, petroleum, electric power, metallurgy, environmental protection and other fields.

[0003] During the operation of centrifugal pumps, especially under high pressure conditions, the problem of shaft end force becomes increasingly prominent. The shaft end force is mainly generated by the inlet high pressure, which will generate a large axial force on the shaft system of the pump, leading to a series of problems such as increased bearing load, mechanical seal failure, shaft bending and deformation, which seriously affect the stability and service life of the centrifugal pump.

[0004] At present, in order to reduce the influence of shaft end force, methods such as adding thrust bearings and adjusting impeller structures are usually adopted. However, these methods often have problems such as complex structure, high manufacturing cost, and difficult maintenance, and the effect is not ideal under certain high-pressure conditions. In addition, some centrifugal pumps also use a single mechanical seal structure. Although it can prevent liquid leakage to a certain extent, the reliability and service life of the mechanical seal are often greatly affected under high-pressure environments. Utility Model Content

[0005] The embodiment of the present application solves the problem in the prior art that a large axial force acts on the main shaft of a centrifugal pump when the inlet pressure is different from the atmospheric pressure by providing a structure for balancing the shaft end force. This achieves the technical effect of balancing the shaft end force and reducing the shaft end force generated by the main shaft, and can reduce vibration and noise, thereby improving the stability and service life of mechanical equipment.

[0006] The utility model embodiment provides a balanced shaft end force structure, including a pump body, a first pump cover, a second pump cover, an impeller, a driving member, a first mechanical seal, a second mechanical seal, a first flushing pipeline and a second flushing pipeline; the first output end of the driving member is connected to the impeller, and the first mechanical seal is connected between the driving member and the impeller; the second output end of the driving member is connected to the second mechanical seal; the first fixed end of the driving member is connected to the first pump cover, and the second fixed end of the driving member is connected to the second pump cover; the pump body is connected to the first pump cover; a liquid inlet and a liquid outlet are provided on the pump body; a first air vent is provided on the first pump cover, and the first air vent is connected to the first mechanical seal; a second air vent is provided on the second pump cover, and the second air vent is connected to the second mechanical seal; one end of the first flushing pipeline is connected to the first air vent, and the other end thereof is connected to the second air vent; one end of the second flushing pipeline is connected to the second air vent, and the other end thereof is connected to the liquid inlet.

[0007] In a possible implementation, it also includes a first water-slinging ring and a second water-slinging ring; the first water-slinging ring is arranged between the first mechanical seal and the driving member, and is connected to the first output end of the driving member; the second water-slinging ring is arranged between the second mechanical seal and the driving member, and is connected to the second output end of the driving member.

[0008] In a possible implementation, the first mechanical seal includes a first dynamic ring seat, a first sealing ring, a second sealing ring, a first stationary ring seat and a first sealing cover; the first dynamic ring seat is sleeved on the first output end of the driving member, one end of the first dynamic ring seat abuts against the first water-slinging ring, and the other end of the first dynamic ring seat abuts against the impeller; a first mounting groove is provided on the first dynamic ring seat, the first sealing ring is arranged in the first mounting groove and is connected to the first dynamic ring seat; the second sealing ring is sleeved on the outer side of the first dynamic ring seat, and one end of the second sealing ring abuts against an end of the first sealing ring away from the impeller; the first stationary ring seat is sleeved on the outer side of the second sealing ring and is connected to the second sealing ring; the first sealing cover is sleeved on the outer side of the first stationary ring seat and is connected to the first stationary ring seat; the first sealing cover is connected to the first pump cover.

[0009] In a possible implementation, the second mechanical seal includes a second dynamic ring seat, a third sealing ring, a fourth sealing ring, a second stationary ring seat and a second sealing cover; the second dynamic ring seat is sleeved on the second output end of the driving member, one end of the second dynamic ring seat abuts the second water-slinging ring, and the other end abuts the fastener; a second mounting groove is provided on the second dynamic ring seat, the third sealing ring is arranged in the second mounting groove and is connected to the second dynamic ring seat; the fourth sealing ring is sleeved on the outer side of the second dynamic ring seat, and one end of the fourth sealing ring abuts against one end of the third sealing ring away from the fastener; the second stationary ring seat is sleeved on the outer side of the fourth sealing ring and is connected to the fourth sealing ring; the second sealing cover is sleeved on the outer side of the second stationary ring seat and is connected to the second stationary ring seat; the second sealing cover is connected to the second pump cover.

[0010] In a possible implementation, it also includes an upper end cover and an exhaust valve; the upper end cover is connected to an end of the second pump cover away from the driving member; the upper end cover is provided with an exhaust hole; the exhaust valve is connected to the upper end cover and communicated with the exhaust hole.

[0011] In a possible implementation, it also includes a main shaft; the main shaft passes through the driving member; the end of the main shaft close to the pump body is connected to the impeller, the first mechanical seal and the first water-slinging ring in sequence; the other end of the main shaft is connected to the second mechanical seal and the second water-slinging ring in sequence.

[0012] One or more technical solutions provided by this application have at least the following technical effects:

[0013] The embodiment of the utility model adopts a structure for balancing shaft end forces, including a pump body, a first pump cover, a second pump cover, an impeller, a driving member, a first mechanical seal, a second mechanical seal, a first flushing pipeline and a second flushing pipeline; the first output end of the driving member is connected to the first mechanical seal, and the second output end of the driving member is connected to the second mechanical seal, and upper and lower machine seal chambers can be formed by the first mechanical seal and the second mechanical seal, and then the upper and lower machine seal chambers are connected by the first flushing pipeline and the second flushing pipeline, so that the pressures of the upper and lower machine seal chambers are equal, achieving the technical effect of balancing the shaft end forces and reducing the shaft end forces generated by the main shaft. The present application solves the problem in the prior art that the axial force acting on the main shaft of the centrifugal pump is large due to the difference between the inlet pressure and the atmospheric pressure, and achieves the technical effect of balancing the shaft end forces and reducing the shaft end forces generated by the main shaft, and can reduce vibration and noise, and improve the stability and service life of mechanical equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments of the utility model will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 A schematic diagram of a balanced shaft end force structure provided in an embodiment of the present application;

[0016] Figure 2 for Figure 1 A magnified image of point A;

[0017] Figure 3 for Figure 1 Enlarged view of point B.

[0018] Icons: 1- pump body; 2- first pump cover; 3- second pump cover; 4- impeller; 5- driving member; 6- first mechanical seal; 61- first dynamic ring seat; 62- first sealing ring; 63- second sealing ring; 64- first stationary ring seat; 65- first sealing gland; 7- second mechanical seal; 71- second dynamic ring seat; 72- third sealing ring; 73- fourth sealing ring; 74- second stationary ring seat; 75- second sealing gland; 8- first flushing pipeline; 9- second flushing pipeline; 10- first water-throwing ring; 11- second water-throwing ring; 12- upper end cover; 13- exhaust valve; 14- main shaft. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0020] In the description of the embodiments of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. The terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0021] During the operation of the centrifugal pump, its main shaft 14 will generate axial end force. The axial end force of the main shaft 14 is the axial force caused by the difference between the suction pressure of the cantilever impeller shaft head and the atmospheric pressure. When the pump inlet pressure is high, the axial force acting on the shaft head of the main shaft 14 is large, causing the rotor to bear a large axial force. The rotor will produce axial displacement under the action of the axial force, causing mutual grinding and collision between the moving and static parts, and causing the centrifugal pump to be unable to run smoothly for a long time, reducing the service life and overall performance of the equipment. Therefore, in order to make the centrifugal pump work normally, it is necessary to find a way to eliminate or balance the axial force of the main shaft 14.

[0022] The utility model embodiment provides a structure for balancing shaft end forces, such as Figure 1-3 As shown, it includes a pump body 1, a first pump cover 2, a second pump cover 3, an impeller 4, a driving member 5, a first mechanical seal 6, a second mechanical seal 7, a first flushing pipeline 8 and a second flushing pipeline 9; the first output end of the driving member 5 is connected to the impeller 4, and the first mechanical seal 6 is connected between the driving member 5 and the impeller 4; the second output end of the driving member 5 is connected to the second mechanical seal 7; the first fixed end of the driving member 5 is connected to the first pump cover 2, and the second fixed end of the driving member 5 is connected to the second pump cover 3; the pump body 1 is connected to the first pump cover 2; a liquid inlet and a liquid outlet are provided on the pump body 1; a first air vent is provided on the first pump cover 2, and the first air vent is connected to the first mechanical seal 6; a second air vent is provided on the second pump cover 3, and the second air vent is connected to the second mechanical seal 7; one end of the first flushing pipeline 8 is connected to the first air vent, and the other end thereof is connected to the second air vent; one end of the second flushing pipeline 9 is connected to the second air vent, and the other end thereof is connected to the liquid inlet.

[0023] Exemplarily, the first flushing pipeline 8 includes a first pipe and a threaded joint; threaded joints are respectively provided at both ends of the first pipe, which are respectively connected to the first air vent and the second air vent through the threaded joints; the second flushing pipeline 9 includes a second pipe and a threaded joint, and threaded joints are respectively provided at both ends of the second pipe, which are respectively connected to the second air vent and the liquid inlet through the threaded joints.

[0024] Exemplarily, the first output end of the driving member 5 is connected to the first mechanical seal 6, and the second output end of the driving member 5 is connected to the second mechanical seal 7. The first mechanical seal 6 and the second mechanical seal 7 can form upper and lower mechanical seal chambers, and then the upper and lower mechanical seal chambers are connected through the first flushing pipeline 8 and the second flushing pipeline 9, so that the pressures of the upper and lower mechanical seal chambers are equal, balancing the force on the axial end of the main shaft 14, thereby achieving the technical effect of reducing the axial force generated by the main shaft 14.

[0025] Exemplarily, a rear ring is provided on the impeller 4, which has the function of throttling and reducing pressure on the high-pressure fluid at the outlet of the impeller 4, thereby reducing the pressure of the liquid entering the lower machine seal chamber, and introducing the liquid between the dynamic and static surfaces of the first mechanical seal 6 for flushing. The first flushing pipeline 8 can lead the liquid in the lower machine seal chamber to between the dynamic and static surfaces of the second mechanical seal 7, thereby flushing the dynamic and static surfaces of the second mechanical seal 7; the second flushing pipeline 9 can lead the liquid in the upper machine seal chamber back to the liquid inlet, forming a closed cycle, thereby maintaining the dynamic balance of the pressures in the upper and lower machine seal chambers.

[0026] Exemplarily, the driving member 5 is a motor or other components.

[0027] Exemplarily, it also includes a main shaft 14, which passes through the motor rotor. One end of the main shaft 14 is connected to the first water-slinging ring 10, the first mechanical seal 6 and the impeller 4 in sequence; the other end of the main shaft 14 is connected to the second water-slinging ring 11 and the second mechanical seal 7 in sequence.

[0028] Exemplarily, the axial end force received by one end of the main shaft 14 can be transmitted to the other end of the main shaft 14. Under the action of the inlet high pressure, one end of the main shaft 14 generates an upward axial end force, which is connected to the upper and lower machine seal chambers through the first flushing pipeline 8, and the static pressures of the upper and lower machine seal chambers are equalized through fluid circulation, that is, the two ends of the main shaft 14 generate axial end forces of equal magnitude and opposite directions, thereby achieving axial end force balance of the main shaft 14.

[0029] Illustratively, a hole is opened on the pump body 1, through which the first vent hole and the first flushing pipeline 8 can be connected; the first flushing pipeline 8 is connected between the pump body 1 and the second pump cover 3, so as to connect the upper and lower machine seal chambers, so as to achieve the technical effect of equal pressure in the upper and lower machine seal chambers and flushing the dynamic and static surfaces of the machine seal, and the second flushing pipeline 9 is used to connect the liquid inlet of the upper pump cover and the pump body 1, so that the first flushing pipeline 8 and the second flushing pipeline 9 form a closed loop.

[0030] For example, the shaft end force is the axial force caused by the difference between the suction pressure of the cantilever impeller shaft head and the atmospheric pressure. When the pump inlet pressure is too high, the axial force acting on the shaft head is large. The shaft end force is specifically:

[0031]

[0032] Among them, p1 is the pump inlet pressure, p a is atmospheric pressure, d h is the diameter of the shaft seal.

[0033] The first mechanical seal 6 and the second mechanical seal 7 adopt the same sealing method, the two ends of the main shaft 14 have the same size, and the upper and lower mechanical seal chambers are connected through the first flushing pipeline 8, so that the shaft end force on the two ends of the main shaft 14 is d h The axial end forces p1 at both ends of the main shaft 14 are equal, thereby achieving a technical effect of balancing the axial end forces at both ends of the main shaft 14.

[0034] In the present application embodiment, Figure 1-3 As shown, it also includes a first water-slinging ring 10 and a second water-slinging ring 11; the first water-slinging ring 10 is arranged between the first mechanical seal 6 and the driving member 5, and is connected to the first output end of the driving member 5; the second water-slinging ring 11 is arranged between the second mechanical seal 7 and the driving member 5, and is connected to the second output end of the driving member 5.

[0035] For example, if the upper machine seal chamber fails to seal and causes liquid leakage, the leaked liquid can be thrown out to the outer wall through the second water-slinging ring 11, and led out of the pump body 1 through the groove at the bottom of the second pump cover 3, thereby achieving the technical effect of preventing liquid from entering the interior of the driving member 5. This method can also timely discover the working status of the second mechanical seal 7. Similarly, when the lower machine seal chamber fails, the first water-slinging ring 10 can be used to throw the liquid out to the outer wall, thereby preventing the liquid from entering the interior of the driving member 5; a leakage observation hole is opened on one side of the pump body 1, so that the working status of the first mechanical seal 6 can be observed in real time.

[0036] In the present application embodiment, Figure 1-3As shown, the first mechanical seal 6 includes a first dynamic ring seat 61, a first sealing ring 62, a second sealing ring 63, a first stationary ring seat 64 and a first sealing gland 65; the first dynamic ring seat 61 is sleeved on the first output end of the driving member 5, one end of the first dynamic ring seat 61 abuts against the first water-slinging ring 10, and the other end of the first dynamic ring seat 61 abuts against the impeller 4; a first mounting groove is opened on the first dynamic ring seat 61, the first sealing ring 62 is arranged in the first mounting groove and is connected to the first dynamic ring seat 61; the second sealing ring 63 is sleeved on the outer side of the first dynamic ring seat 61, and one end of the second sealing ring 63 abuts against one end of the first sealing ring 62 away from the impeller 4; the first stationary ring seat 64 is sleeved on the outer side of the second sealing ring 63 and is connected to the second sealing ring 63; the first sealing gland 65 is sleeved on the outer side of the first stationary ring seat 64 and is connected to the first stationary ring seat 64; the first sealing gland 65 is connected to the first pump cover 2.

[0037] Exemplarily, the first mechanical seal 6 further includes a first cylindrical pin, a second cylindrical pin and a third cylindrical pin; one end of the first cylindrical pin is connected to the first dynamic ring seat 61, and the other end of the first cylindrical pin is connected to the first sealing ring 62; one end of the second cylindrical pin is connected to the second sealing ring 63, and the other end of the second cylindrical pin is connected to the first stationary ring seat 64; one end of the third cylindrical pin is connected to the first stationary ring seat 64, and the other end of the third cylindrical pin is connected to the first sealing gland 65. The first cylindrical pin, the second cylindrical pin and the third cylindrical pin are all used for connection and positioning between components, and their precision is relatively high.

[0038] Exemplarily, the first mechanical seal 6 further includes a first sealing ring, a second sealing ring, a third sealing ring, a fourth sealing ring and a fifth sealing ring; the first sealing ring is arranged between the first stationary ring seat 64 and the first sealing gland 65; the second sealing ring is arranged between the first sealing gland 65 and the first pump cover 2; the third sealing ring is arranged between the first stationary ring seat 64 and the second sealing ring 63; the fourth sealing ring is arranged between the first dynamic ring seat 61 and the first sealing ring 62; the fifth sealing ring is arranged between the first dynamic ring seat 61 and the main shaft 14. The first sealing ring, the second sealing ring, the third sealing ring, the fourth sealing ring and the fifth sealing ring are all used for sealing between components, so that the sealing performance of the first mechanical seal 6 is better.

[0039] In the present application embodiment, Figure 1-3As shown, the second mechanical seal 7 includes a second dynamic ring seat 71, a third sealing ring 72, a fourth sealing ring 73, a second stationary ring seat 74 and a second sealing gland 75; the second dynamic ring seat 71 is sleeved on the second output end of the driving member 5, one end of the second dynamic ring seat 71 abuts against the second water-slinging ring 11, and the other end abuts against the fastener; a second mounting groove is provided on the second dynamic ring seat 71, the third sealing ring 72 is arranged in the second mounting groove, and is connected to the second dynamic ring seat 71; the fourth sealing ring 73 is sleeved on the outer side of the second dynamic ring seat 71, and one end of the fourth sealing ring 73 abuts against one end of the third sealing ring 72 away from the fastener; the second stationary ring seat 74 is sleeved on the outer side of the fourth sealing ring 73, and is connected to the fourth sealing ring 73; the second sealing gland 75 is sleeved on the outer side of the second stationary ring seat 74, and is connected to the second stationary ring seat 74; the second sealing gland 75 is connected to the second pump cover 3.

[0040] Exemplarily, the second mechanical seal 7 further includes a fourth cylindrical pin, a fifth cylindrical pin and a sixth cylindrical pin; one end of the fourth cylindrical pin is connected to the second dynamic ring seat 71, and the other end of the fourth cylindrical pin is connected to the third sealing ring 72; one end of the fifth cylindrical pin is connected to the fourth sealing ring 73, and the other end of the fifth cylindrical pin is connected to the second stationary ring seat 74; one end of the sixth cylindrical pin is connected to the second stationary ring seat 74, and the other end of the sixth cylindrical pin is connected to the second sealing gland 75. The fourth cylindrical pin, the fifth cylindrical pin and the sixth cylindrical pin are all used for connection and positioning between components, and their precision is relatively high.

[0041] Exemplarily, the second mechanical seal 7 further includes a sixth sealing ring, a seventh sealing ring, an eighth sealing ring, a ninth sealing ring and a tenth sealing ring; the sixth sealing ring is arranged between the second stationary ring seat 74 and the second sealing gland 75; the seventh sealing ring is arranged between the second sealing gland 75 and the second pump cover 3; the eighth sealing ring is arranged between the second stationary ring seat 74 and the fourth sealing ring 73; the ninth sealing ring is arranged between the second dynamic ring seat 71 and the third sealing ring 72; and the tenth sealing ring is arranged between the second dynamic ring seat 71 and the main shaft 14. The sixth sealing ring, the seventh sealing ring, the eighth sealing ring, the ninth sealing ring and the tenth sealing ring are all used for sealing between components, so that the sealing performance of the second mechanical seal 7 is better.

[0042] In the present application embodiment, Figure 1-3 As shown, it also includes an upper end cover 12 and an exhaust valve 13; the upper end cover 12 is connected to the end of the second pump cover 3 away from the driving member 5; the upper end cover 12 is provided with an exhaust hole; the exhaust valve 13 is connected to the upper end cover 12 and communicated with the exhaust hole.

[0043] Exemplarily, an exhaust valve 13 is welded on the top of the upper end cover 12 to exhaust the pump group.

[0044] In the present application embodiment, Figure 1-3As shown, it also includes a main shaft 14; the main shaft 14 passes through the driving member 5; the end of the main shaft 14 close to the pump body 1 is connected to the impeller 4, the first mechanical seal 6 and the first water-slinging ring 10 in sequence; the other end of the main shaft 14 is connected to the second mechanical seal 7 and the second water-slinging ring 11 in sequence.

[0045] The first mechanical seal 6 and the second mechanical seal 7 of the present application are respectively installed at the two ends of the main shaft 14, and the upper and lower mechanical seal chambers are connected through the first flushing pipeline 8 and the second flushing pipeline 9, so that the pressures of the upper and lower mechanical seal chambers are equal, thereby generating equal and opposite axial end forces at the two ends of the main shaft 14, achieving the effect of balancing the forces at the two ends of the main shaft 14, thereby reducing the axial force caused by the difference between the suction pressure of the impeller 4 shaft head and the atmospheric pressure. The present application has a simple structure, can effectively reduce the imbalance of the axial end force, and reduce the vibration and noise of the centrifugal pump, improve the stability of the mechanical equipment, and extend the service life of the mechanical equipment.

[0046] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other. Each embodiment focuses on the differences from other embodiments.

[0047] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.

Claims

1. A structure for balancing shaft end forces, characterized in that: It comprises a pump body (1), a first pump cover (2), a second pump cover (3), an impeller (4), a driving member (5), a first mechanical seal (6), a second mechanical seal (7), a first flushing pipeline (8) and a second flushing pipeline (9); The first output end of the driving member (5) is connected to the impeller (4), and the first mechanical seal (6) is connected between the driving member (5) and the impeller (4); The second output end of the driving member (5) is connected to a second mechanical seal (7); The first fixed end of the driving member (5) is connected to the first pump cover (2), and the second fixed end of the driving member (5) is connected to the second pump cover (3); The pump body (1) is connected to the first pump cover (2); the pump body (1) is provided with a liquid inlet and a liquid outlet; The first pump cover (2) is provided with a first vent hole, the first vent hole being in communication with the first mechanical seal (6); The second pump cover (3) is provided with a second vent hole, and the second vent hole is in communication with the second mechanical seal (7); One end of the first flushing pipeline (8) is in communication with the first vent hole, and the other end of the first flushing pipeline (8) is in communication with the second vent hole; One end of the second flushing pipeline (9) is in communication with the second vent hole, and the other end thereof is in communication with the liquid inlet.

2. The balancing shaft end force structure according to claim 1 is characterized in that: It also includes a first water-spinning ring (10) and a second water-spinning ring (11); The first water-slinging ring (10) is arranged between the first mechanical seal (6) and the driving member (5), and is connected to a first output end of the driving member (5); The second water-slinging ring (11) is arranged between the second mechanical seal (7) and the driving member (5), and is connected to a second output end of the driving member (5).

3. The balancing shaft end force structure according to claim 2 is characterized in that: The first mechanical seal (6) comprises a first dynamic ring seat (61), a first sealing ring (62), a second sealing ring (63), a first stationary ring seat (64) and a first sealing gland (65); The first moving ring seat (61) is sleeved on the first output end of the driving member (5), one end of the first moving ring seat (61) abuts against the first water-slinging ring (10), and the other end of the first moving ring seat (61) abuts against the impeller (4); A first mounting groove is formed on the first moving ring seat (61), and the first sealing ring (62) is arranged in the first mounting groove and connected to the first moving ring seat (61); The second sealing ring (63) is sleeved on the outer side of the first moving ring seat (61), and one end of the second sealing ring (63) is in contact with one end of the first sealing ring (62) away from the impeller (4); The first stationary ring seat (64) is sleeved on the outer side of the second sealing ring (63) and is connected to the second sealing ring (63); The first sealing gland (65) is sleeved on the outer side of the first stationary ring seat (64) and is connected to the first stationary ring seat (64); The first sealing gland (65) is connected to the first pump cover (2).

4. The balancing shaft end force structure according to claim 2 is characterized in that: The second mechanical seal (7) comprises a second dynamic ring seat (71), a third sealing ring (72), a fourth sealing ring (73), a second stationary ring seat (74) and a second sealing gland (75); The second moving ring seat (71) is sleeved on the second output end of the driving member (5), one end of the second moving ring seat (71) abuts against the second water-slinging ring (11), and the other end of the second moving ring seat (71) abuts against the fastener; A second mounting groove is formed on the second dynamic ring seat (71), and the third sealing ring (72) is arranged in the second mounting groove and connected to the second dynamic ring seat (71); The fourth sealing ring (73) is sleeved on the outer side of the second dynamic ring seat (71), and one end of the fourth sealing ring (73) abuts against an end of the third sealing ring (72) away from the fastener; The second stationary ring seat (74) is sleeved on the outer side of the fourth sealing ring (73) and is connected to the fourth sealing ring (73); The second sealing gland (75) is sleeved on the outer side of the second stationary ring seat (74) and is connected to the second stationary ring seat (74); The second sealing gland (75) is connected to the second pump cover (3).

5. The balancing shaft end force structure according to claim 1 is characterized in that: It also includes an upper end cover (12) and an exhaust valve (13); The upper end cover (12) is connected to an end of the second pump cover (3) away from the driving member (5); The upper end cover (12) is provided with an exhaust hole; The exhaust valve (13) is connected to the upper end cover (12) and communicates with the exhaust hole.

6. The balancing shaft end force structure according to claim 2 is characterized in that: Also included is the spindle (14); The main shaft (14) passes through the driving member (5); One end of the main shaft (14) close to the pump body (1) is connected in sequence to the impeller (4), the first mechanical seal (6) and the first water slinger (10); The other end of the main shaft (14) is connected in sequence to the second mechanical seal (7) and the second water-slinging ring (11).

Images