Mechanical sealing structure of nuclear main pump

Abstract

The invention discloses a nuclear main pump mechanical sealing structure, and relates to the technical field of nuclear main pump sealing. The device comprises a main shaft and a shell, and further comprises a movable ring which is arranged on the main shaft in a sleeving mode and rotates synchronously with the main shaft, a gap is reserved between the circumferential side of the movable ring and the shell, one end of the movable ring is a contact surface, and a lubricating space is formed in the contact surface; the static ring is installed on the shell in a sealed and sliding mode, the movable ring and the static ring are coaxial, the main shaft penetrates through the static ring, and a gap is reserved between the inner side of the static ring and the main shaft. When the nuclear main pump runs, the main shaft continuously rotates and the main shaft rotates to generate certain amplitude, the lubricating liquid is effectively smeared between the movable ring and the static ring, so that the friction resistance between the movable ring and the static ring is reduced, the use effect of the movable ring and the static ring is improved, the abrasion strength between the movable ring and the static ring is reduced, and the service life of the movable ring and the static ring is prolonged. And frequent replacement of the moving ring and the static ring is avoided, and the maintenance cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of nuclear main pump sealing, and in particular to a nuclear main pump mechanical sealing structure. Background Art

[0002] The main shaft sealing performance of the nuclear main pump is directly related to the safe operation of the nuclear power plant as one of the key equipment. The existing main shaft sealing technology of the nuclear main pump mainly adopts a mechanical seal structure, which realizes the rotary seal through the friction pair of the dynamic ring on the main shaft sleeve and the static ring on the shell. However, this sealing method has some problems during long-term operation.

[0003] First, since the working environment of nuclear main pumps is usually harsh and the medium has the characteristics of high temperature, high pressure and radioactivity, the friction between the dynamic ring and the static ring will lead to increased wear. This wear will not only reduce the sealing effect, but also may cause leakage of radioactive media, causing serious harm to the environment and equipment. Secondly, after a period of use, the dynamic ring and the static ring need to be disassembled and replaced due to severe wear, which increases maintenance costs.

[0004] Therefore, the present invention proposes a nuclear main pump mechanical seal structure. Summary of the invention

[0005] The purpose of this application is to solve the problems in the above-mentioned background technology, and to provide a nuclear main pump mechanical seal structure.

[0006] In order to achieve the above-mentioned purpose, this application specifically adopts the following technical solutions:

[0007] The mechanical seal structure of the nuclear main pump includes the main shaft and the housing, and also includes:

[0008] A moving ring is sleeved on the main shaft and rotates synchronously with the main shaft, a gap is left between the circumference of the moving ring and the housing, one end of the moving ring is a contact surface, and a lubrication space is provided on the contact surface;

[0009] A stationary ring is sealingly and slidably mounted on the housing, the dynamic ring is coaxial with the stationary ring and the main shaft passes through the stationary ring, and a gap is left between the inner side of the stationary ring and the main shaft;

[0010] A sealing end cover is installed on the housing, one end of the main shaft passes through the sealing end cover, and a resistance spring is installed between the sealing end cover and the stationary ring, so that the resistance spring provides an elastic resistance force in the axial direction of the stationary ring and makes one end of the stationary ring resist against the contact surface of the dynamic ring;

[0011] The oil circulation mechanism is installed on the housing and forms a lubricating oil path with the lubricating space to continuously supply lubricating liquid to the lubricating space in a trickle form.

[0012] Furthermore, a convex ring is constructed on the contact surface of the moving ring, and a plurality of arc-shaped convex plates are installed in the convex ring and in a circular array around the axis of the moving ring to form the lubrication space, with a gap left between each arc-shaped convex plate, and the number of circles is not less than two, the arc-shaped convex plates of two adjacent circles are staggered, and the convex ring is flush with the end face of the arc-shaped convex plate.

[0013] Furthermore, the circular array on the end face of the stationary ring is provided with two oil delivery holes, and a plug is constructed at one end of the oil delivery hole away from the dynamic ring. The plug is horizontally slidably inserted on the sealing end cover, and two circulating oil circuits are symmetrically arranged on the sealing end cover. The two plugs are respectively connected to the two circulating oil circuits, and the oil circulation mechanism remains connected to the two circulating oil circuits.

[0014] Furthermore, the oil circulation mechanism includes an oil box arranged on the outer shell, and the upper end and the lower end of one side of the oil box are connected to oil pipes, and the two oil pipes are respectively connected to two circulating oil circuits. A power part is installed on one of the oil pipes, and the lubricating liquid in the oil box is transported to the corresponding oil pipe through the power part.

[0015] Furthermore, the power part includes a mounting tube installed on the outer shell, and a trigger rod is elastically and slidably inserted at one end of the mounting tube, and the free end of the trigger rod is in contact with the outer peripheral side of the dynamic ring. When the dynamic ring has a small amplitude during rotation, the trigger rod moves vertically with a small amplitude. A conversion mechanism connected to the oil pipeline is installed on the mounting tube. When the trigger rod moves, the conversion mechanism is used to convert the moving power of the trigger rod into oil transmission force.

[0016] Furthermore, the conversion mechanism includes an installation box connected to the oil pipeline, a transmission gear is rotatably installed in the installation box, one of the transmission gear rotating shafts is located outside and is installed with a rotating cylinder, a driving plate is rotatably installed in the installation cylinder, a wedge plate is vertically elastically slidably installed on the top of the driving plate, a circular array at the bottom end of the rotating cylinder is provided with a plurality of wedge grooves for inserting the wedge plate, and a plurality of wedge grooves form an annular groove at the bottom of the rotating cylinder, the driving plate is linked with the trigger rod, and when the trigger rod moves back and forth, the driving plate rotates back and forth around its own axis.

[0017] Furthermore, an actuator rod is vertically slidably installed in the installation cylinder, a conversion hole is opened through the axis of the drive plate, a spiral groove is opened in an annular manner on the inner circumference of the conversion hole, and a guide plate located in the spiral groove is constructed on the outer side of the actuator rod. The actuator rod is connected to the trigger rod in a non-contact transmission manner. When the trigger rod moves a small amplitude, the actuator rod moves a larger amplitude than the trigger rod.

[0018] Furthermore, a clamping plate is slidably installed on the mounting tube, a clamping spring is installed between the clamping plate and the mounting tube, one end of the clamping plate is abutted against one end of the trigger rod, a connecting rod is coaxially constructed on the clamping plate, and the connecting rod is connected to the actuator rod in non-contact transmission.

[0019] Furthermore, the mounting tube has a small diameter cavity and a large diameter cavity, the actuator rod is slidably inserted in the small diameter cavity, and the end of the connecting rod away from the trigger rod is constructed with a push plate located in the large diameter cavity, the large diameter cavity and the small diameter cavity are connected to each other, and a sealing area is formed between the push plate and the actuator rod.

[0020] Furthermore, one end of the trigger rod is an outer arc surface, the oil box is annular, and two filter plates are installed in the oil box. The two filter plates divide the interior of the oil box into two upper and lower areas.

[0021] The beneficial effects of this application are as follows:

[0022] The present application effectively applies lubricating fluid between the moving ring and the stationary ring when the core main pump is running, the main shaft rotates continuously and the main shaft rotates with a certain amplitude, thereby reducing the friction resistance between the moving ring and the stationary ring, improving the use effect of the moving ring and the stationary ring, reducing the wear between the moving ring and the stationary ring, avoiding frequent replacement of the moving ring and the stationary ring, and reducing maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the three-dimensional structure of this application;

[0024] Figure 2 This application Figure 1 Stereoscopic view Figure 1 ;

[0025] Figure 3 This application Figure 1 Partial stereoscopic cutaway Figure 2 ;

[0026] Figure 4 This application Figure 1 Partial stereoscopic cutaway Figure 3 ;

[0027] Figure 5 This application Figure 1 Partial stereoscopic cutaway Figure 4 ;

[0028] Figure 6 This is the static ring structure diagram of this application;

[0029] Figure 7 This is the structural diagram of the driver board of this application;

[0030] Figure 8This is an exploded view of the installation tube structure of this application;

[0031] Fig. 9 This application Figure 8 A schematic diagram of another local perspective;

[0032] Fig.10 This application Figure 2 A magnified view of the structure at center;

[0033] Fig.11 This application Figure 2 A magnified view of the structure at B in the middle;

[0034] Fig.12 This application Figure 3 Enlarged view of the structure at point C in the middle.

[0035] 1. Moving ring; 2. Spindle; 3. Casing; 4. Stationary ring; 5. Sealing end cover; 6. Resistance spring; 7. Oil circulation mechanism; 701. Oil box; 702. Oil delivery pipe; 8. Convex ring; 9. Arc convex plate; 10. Oil delivery hole; 11. Insert tube; 12. Circulating oil circuit; 13. Push plate; 14. Power part; 1401. Mounting cylinder; 1402. Trigger rod; 15. Conversion mechanism; 1501. Mounting box; 1502. Transmission gear; 1503. Rotating cylinder; 1504. Driving plate; 1505. Wedge plate; 1506. Wedge groove; 16. Actuator rod; 17. Conversion hole; 18. Spiral groove; 19. Guide plate; 20. Resistance plate; 21. Resistance spring; 22. Connecting rod; 23. Small diameter cavity; 24. Large diameter cavity; 25. Filter plate. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0037] like Figure 1-Figure 12 As shown, a nuclear main pump mechanical seal structure proposed in an embodiment of the present application includes a main shaft 2 and a housing 3. The partial structure of the main shaft 2 and the housing 3 shown in the figure also includes:

[0038] The moving ring 1 is mounted on the main shaft 2 and rotates synchronously with the main shaft 2. A gap is left between the circumference of the moving ring 1 and the housing 3. The existing nuclear main pump will produce certain vibrations and deviations when running at high speed. The gap between the moving ring 1 and the housing 3 can effectively prevent the main shaft 2 or the outer side of the moving ring 1 from being damaged due to hard interference. One end of the moving ring 1 is a contact surface, and a lubrication space is provided on the contact surface;

[0039] The stationary ring 4 is sealingly and slidably mounted on the housing 3. Specifically, a ring groove is provided on the outer circumference of the stationary ring 4, and an O-ring is provided in the ring groove to play a sealing role. The dynamic ring 1 is coaxial with the stationary ring 4 and the main shaft 2 passes through the stationary ring 4. A gap is left between the inner side of the stationary ring 4 and the main shaft 2. Specifically, the diameter of the stationary ring 4 is larger than the diameter of the dynamic ring 1. When the main shaft 2 vibrates and deviates to a certain extent during high-speed rotation, the main shaft 2 will not contact the inner circumference of the stationary ring 4.

[0040] The sealing end cover 5 can be installed on the housing 3 by bolts. Specifically, a hole is coaxially opened on the sealing end cover 5, and a sealing bearing is arranged inside the hole. One end of the main shaft 2 passes through the sealing bearing of the sealing end cover 5. The sealing bearing and the sealing end cover 5 can be installed by a rubber ring, so that when the main shaft 2 vibrates and deviates, the sealing bearing will also deviate synchronously. A resistance spring 6 is installed between the sealing end cover 5 and the static ring 4. The resistance spring 6 is used to provide an elastic resistance force in the axial direction of the static ring 4, and one end of the static ring 4 is made to resist the contact surface of the dynamic ring 1. When the sealing end cover 5 is installed on the housing 3 by bolts, the resistance spring 6 is in a semi-compressed state, and the static ring 4 resists the contact surface of the dynamic ring 1. The resistance spring 6 ensures that the static ring 4 can always resist the dynamic ring 1. In this way, when the main shaft 2 rotates, the dynamic ring 1 will also resist and rotate on the static ring 4, effectively ensuring the sealing effect.

[0041] The oil circulation mechanism 7 is installed on the outer shell 3 and forms a lubricating oil circuit with the lubrication space, and continuously provides lubricating liquid to the lubrication space in the form of trickle flow. That is to say, when the main shaft 2 of the nuclear main pump rotates, the moving ring 1 will also rotate at the same time. At this time, the oil circulation mechanism 7 will continuously transport the lubricating liquid to the lubrication space in the form of a small flow output, and the lubricating liquid in the lubrication space will be located between the moving ring 1 and the static ring 4. When the main shaft 2 rotates with a small amplitude, the lubricating liquid will be distributed more evenly, thereby further improving the lubrication effect. By utilizing the existing nuclear main pump when it is running, the main shaft 2 continues to rotate and the main shaft 2 rotates with a certain amplitude, the lubricating liquid is effectively applied between the moving ring 1 and the static ring 4, thereby reducing the friction resistance between the moving ring 1 and the static ring 4, improving the use effect of the moving ring 1 and the static ring 4, reducing the wear between the moving ring 1 and the static ring 4, avoiding frequent replacement of the moving ring 1 and the static ring 4, and reducing maintenance costs.

[0042] like Figure 2 and Figure 6 As shown, in some embodiments, a convex ring 8 is constructed on the contact surface of the moving ring 1, and a plurality of arc-shaped convex plates 9 are installed in the convex ring 8 and in a circular array around the axis of the moving ring 1 to form a lubrication space, such as Figure 6As shown, there is a gap between each arc-shaped convex plate 9, and the number of circles is not less than two circles. The arc-shaped convex plates 9 of two adjacent circles are staggered, and the convex ring 8 is flush with the end face of the arc-shaped convex plate 9. The design of the convex ring 8 plays a major sealing role to prevent leakage. When the lubricating liquid enters the convex ring 8, when the lubricating liquid is located between the two arc-shaped convex plates 9 of the same circle, the centrifugal force will throw the lubricating liquid out and approach the inner edge of the convex ring 8 to quickly lubricate the convex ring 8. Multiple arc-shaped convex plates 9 also play the role of auxiliary sealing support to ensure that the static ring 4 is evenly stressed. When the main shaft 2 has a small amplitude, because the dynamic ring 1 is still in a high-speed rotation state at this time, the small rotation of the main shaft 2 can make the convex ring 8 and the arc-shaped convex plate 9 further complete the lubrication, thereby improving the lubrication effect.

[0043] like Figure 4 and Fig.11As shown, in some embodiments, two oil delivery holes 10 are provided in a circular array on the end face of the stationary ring 4, and a plug 11 is constructed at one end of the oil delivery hole 10 away from the dynamic ring 1. The plug 11 is horizontally slidably inserted on the sealing end cover 5, and two circulating oil circuits 12 are symmetrically arranged on the sealing end cover 5. The two plugs 11 are respectively connected to the two circulating oil circuits 12. The circulating oil circuit 12 includes an L-shaped oil pipe pre-buried in the sealing end cover 5, and the outer peripheral side of the plug 11 is fitted with a preset hole in the sealing end cover 5 to play a guiding role, while the inner peripheral side of the plug 11 is slidably inserted at one end of the oil pipe in the horizontal direction. When the sealing end cover 5 is installed, the stationary ring 4 is After the ring 4 contacts the moving ring 1, the insert 11 is inserted into the oil pipe. Preferably, a sealing ring can be installed on the inner circumference of the insert 11 to improve the sealing effect. Because the static ring 4 will not produce a large horizontal movement when in use, the sealing ring is not easily damaged, thereby ensuring the sealing effect and preventing the lubricant from leaking when flowing. The oil circulation mechanism 7 is connected with the two circulating oil circuits 12. The oil will first enter the circulating oil circuit 12 located at the upper part through the oil circulation mechanism 7, and then pass through the oil delivery hole 10 located at the top to enter the convex ring 8. The convex ring 8 is filled with lubricating liquid, or because of gravity. When the lubricating fluid flows into the circulating oil circuit 12 below, the lubricating fluid will pass through the oil delivery hole 10 below, and finally enter the oil circulation mechanism 7 through the corresponding circulating oil circuit 12 to complete the circulation of the lubricating fluid. It should be noted that the oil delivery hole 10 below is located in the convex ring 8, that is, when a certain height of lubricating fluid is accumulated in the convex ring 8, the lubricating fluid in the convex ring 8 will flow into the oil delivery hole 10 below, so that when the multiple arc-shaped convex plates 9 rotate, the ends of the arc-shaped convex plates 9 will bring the accumulated lubricating fluid upward, thereby achieving continuous lubrication. Preferably, the two end surfaces of the arc-shaped convex plates 9 can be There is a certain depression, so that more lubricating fluid can be brought in, which effectively prevents the lubricating fluid of the static ring 4 from drying up and realizes continuous lubrication. Specifically, notches are opened at the upper and lower end faces of the shell 3, and the sealing end cover 5 is constructed with two positioning blocks matching the notches, which play a role in auxiliary positioning, and positioning holes are opened on the outer peripheral side of the sealing end cover 5, and threaded holes are opened on the peripheral side of the shell 3. The sealing end cover 5 is positioned by headless bolts, which effectively prevents the static ring 4 and the dynamic ring 1 from excessively large contact force and causing increased wear. A sealing ring can be installed on the contact portion between the sealing end cover 5 and the end face of the shell 3 to further improve the sealing performance.

[0044] like Figure 4As shown, in some embodiments, the oil circulation mechanism 7 includes an oil box 701 arranged on the outer shell 3, and the upper end and the lower end of one side of the oil box 701 are connected to the oil pipe 702, and the two oil pipes 702 are respectively connected to the two circulating oil circuits 12. After the sealing end cover 5 is installed, the oil pipe 702 can be installed between the oil box 701 and the circulating oil circuit 12 by bolts. A power part 14 is installed on one of the oil pipes 702, and the lubricating liquid in the oil box 701 is transported to the corresponding oil pipe 702 through the power part 14. The power part 14 can transport the lubricating liquid in the oil box 701 to the oil pipe 702 located above. The upper part of the oil box 701 is connected to an oil delivery pipe, which is used to inject lubricating liquid into the oil box 701. The opening of the oil delivery pipe can be screwed with a sealing bolt to prevent oil evaporation and the entry of stains.

[0045] like Figure 8 As shown, in some embodiments, the power member 14 includes a mounting cylinder 1401 mounted on the housing 3, and a trigger rod 1402 is elastically slidably inserted at one end of the mounting cylinder 1401, and the free end of the trigger rod 1402 abuts against the outer peripheral side of the dynamic ring 1. When the dynamic ring 1 has a small amplitude during rotation, the trigger rod 1402 moves vertically with a small amplitude. A conversion mechanism 15 connected to the oil delivery pipe 702 is installed on the mounting cylinder 1401. When the trigger rod 1402 moves, the conversion mechanism 15 is used to convert the moving power of the trigger rod 1402 into oil transmission force. That is to say, at the height of the main shaft 2, the trigger rod 1402 is moved. When a small amplitude of vibration occurs during high-speed rotation, the moving ring 1 will also move with the amplitude. Since the trigger rod 1402 abuts against the outer peripheral side of the moving ring 1, the trigger rod 1402 will also move up and down with a small amplitude. As the trigger rod 1402 moves, the small up and down movement of the trigger rod 1402 will be converted into the delivery of lubricating fluid through the conversion mechanism 15, so that no additional driving force is required to achieve the trickle flow of the lubricating fluid. The lubricating fluid flows in the form of a trickle, which not only ensures the lubrication between the static ring 4 and the moving ring 1, but also can effectively prevent the sealing effect from being affected by excessive oil pressure between the static ring 4 and the moving ring 1.

[0046] like Figure 8 and Fig. 9As shown, in some embodiments, the conversion mechanism 15 includes a mounting box 1501 connected to the oil delivery pipe 702, a transmission gear 1502 is rotatably mounted in the mounting box 1501, one of the transmission gears 1502 rotation axis is located outside and is mounted with a rotating cylinder 1503, a driving plate 1504 is rotatably mounted in the mounting cylinder 1401, a wedge plate 1505 is vertically elastically slidably mounted on the top of the driving plate 1504, specifically, a mounting groove is opened on the driving plate 1504, the wedge plate 1505 is slidably mounted in the mounting groove, and a wedge plate 1505 is installed between the wedge plate 1505 and the mounting groove. There is a resisting spring piece, and a circular array is provided at the bottom of the rotating cylinder 1503 with a plurality of wedge-shaped grooves 1506 for inserting the wedge-shaped plate 1505. The plurality of wedge-shaped grooves 1506 form an annular groove at the bottom of the rotating cylinder 1503. The driving plate 1504 is linked with the trigger rod 1402. When the trigger rod 1402 moves back and forth, the driving plate 1504 reciprocates around its own axis. That is to say, when the trigger rod 1402 moves back and forth in a small amplitude, the driving plate 1504 also reciprocates. However, when the driving plate 1504 rotates forward, the plane on one side of the wedge plate 1505 will contact the wedge groove 1 506, thereby driving one side plane of the wedge groove 1506 to move, and when the driving plate 1504 is reversed, the inclined surface of the wedge groove 1506 will contact the inclined surface of the wedge groove 1506, thereby causing the wedge groove 1506 to retract into the mounting groove, thereby causing the rotating cylinder 1503 to rotate in one direction. As the rotating cylinder 1503 rotates in one direction, it should be noted that the rotation of the two transmission gears 1502 and the rotating cylinder 1503 are tightly matched to overcome the elastic resistance of the wedge plate 1505, and the wedge plate will not be caused by the inclined surface of the wedge groove 1506. When in contact, the rotating cylinder 1503 is caused to rotate, and the rotation of the rotating cylinder 1503 will cause the transmission gear 1502 connected thereto to rotate. Because the two transmission gears 1502 are meshed with each other, when one of the transmission gears 1502 rotates, it will drive the other transmission gear 1502 to rotate. When the oil box 701 is filled with oil, the oil pipe 702 located above will also be filled with lubricating liquid. As the two transmission gears 1502 rotate, the gap between the two transmission gears 1502 will transport the lubricating liquid to the circulating oil circuit 12 located above, thereby achieving a trickle effect.

[0047] like Fig.10As shown, in some embodiments, an actuator rod 16 is vertically slidably installed in the installation cylinder 1401, a conversion hole 17 is penetrated at the axis of the driving plate 1504, a spiral groove 18 is annularly opened on the inner circumference of the conversion hole 17, and a guide plate 19 located in the spiral groove 18 is constructed on the outer side of the actuator rod 16. That is to say, when the actuator rod 16 moves back and forth, the movement of the actuator rod 16 will drive the guide plate 19 to move vertically. Because the guide plate 19 is located in the spiral groove 18, the vertical movement of the actuator rod 16 will drive the driving plate 1504 to move vertically. 04 reciprocatingly rotates, thereby realizing the rotation of the driving plate 1504. The actuator rod 16 is connected to the trigger rod 1402 in a non-contact transmission manner. When the trigger rod 1402 moves a small amplitude, the actuator rod 16 moves a large amplitude compared to the trigger rod 1402. In order to improve the rotation effect of the transmission gear 1502, when the trigger rod 1402 moves a small amplitude, the actuator rod 16 will move synchronously and the movement amplitude will increase, and the rotation amplitude of the transmission gear 1502 will also increase, thereby improving the effect of conveying lubricating fluid and improving the oil conveying efficiency.

[0048] like Fig.10 and Fig.11 As shown, in some embodiments, a clamping plate 20 is slidably installed on the mounting cylinder 1401, and a clamping spring 21 is installed between the clamping plate 20 and the mounting cylinder 1401, one end of the clamping plate 20 is in contact with one end of the trigger rod 1402, and a connecting rod 22 is coaxially constructed on the clamping plate 20, and the connecting rod 22 is non-contactly transmitted and connected to the actuator rod 16. In this embodiment, an annular groove is provided on the outer peripheral side of the trigger rod 1402, and a sealing ring is installed in the annular groove to prevent leakage. When the trigger rod 1402 moves vertically, the trigger rod 1402 will resist the vertical movement of the clamping plate 20, and the diameter of the clamping plate 20 is larger than the diameter of the trigger rod 1402. The outer peripheral side of the clamping plate 20 is in contact with the inner peripheral side of the mounting cylinder 1401, and a sealing ring can also be installed on the outer peripheral side of the clamping plate 20 for secondary sealing, which not only improves the sealing effect but also ensures the rotation of the transmission gear 1502.

[0049] like Figure 8 and Fig.10As shown, in some embodiments, the installation cylinder 1401 has a small diameter cavity 23 and a large diameter cavity 24, the actuator rod 16 is slidably inserted in the small diameter cavity 23, and the end of the connecting rod 22 away from the trigger rod 1402 is configured with a push plate 13 located in the large diameter cavity 24, the large diameter cavity 24 and the small diameter cavity 23 are connected to each other, and a sealing area is formed between the push plate 13 and the actuator rod 16. When the trigger rod 1402 moves vertically back and forth, it will drive the connecting rod 22 to move vertically back and forth, because the push plate on the connecting rod 22 13 is located in the large diameter cavity 24, so as the push plate 13 moves upward, the air in the large diameter cavity 24 will be squeezed into the small diameter cavity 23. Because the diameter of the large diameter cavity 24 is larger than the diameter of the small diameter cavity 23, the vertical reciprocating amplitude of the actuator rod 16 located in the small diameter cavity 23 will increase. The design of the clamping spring 21 is to help reset the push plate 13 and ensure that the trigger rod 1402 always contacts the outer peripheral side of the moving ring 1. A hole is opened on the rotating cylinder 1503 to ensure that the actuator rod 16 can move vertically.

[0050] like Figure 4 and Figure 5 As shown, in some embodiments, one end of the trigger rod 1402 is an outer arc surface, the oil box 701 is annular, and two filter plates 25 are installed in the oil box 701. The two filter plates 25 divide the interior of the oil box 701 into two upper and lower areas. When the oil in the oil box 701 circulates, the convex ring 8 and the arc-shaped convex plate 9 will produce fine metal chips due to long-term friction with the static ring 4. With the accumulation of a long time, the metal chips will increase, and the metal chips are prevented from entering the static ring 4 and the dynamic ring 1 along the oil path to increase the friction. The filter plate 25 in the oil box 701 can effectively prevent the oil from entering between the convex ring 8 and the static ring 4, and when the static ring 4 and the dynamic ring 1 rub to form metal chips, the flowing lubricating fluid will drive some of the metal chips, and finally the impurities are prevented from entering between the static ring 4 and the dynamic ring 1 for a second time through the filtration of the filter plate 25, thereby further reducing the friction between the static ring 4 and the dynamic ring 1 and improving the use efficiency of the static ring 4 and the dynamic ring 1.

[0051] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A nuclear main pump mechanical seal structure, comprising a main shaft (2) and a housing (3), characterized in that: Also includes: A moving ring (1) is sleeved on the main shaft (2) and rotates synchronously with the main shaft (2), a gap is left between the circumference of the moving ring (1) and the outer shell (3), one end of the moving ring (1) is a contact surface, and a lubrication space is provided on the contact surface; A stationary ring (4) is sealingly and slidably mounted on the housing (3); the dynamic ring (1) is coaxial with the stationary ring (4) and the main shaft (2) passes through the stationary ring (4); a gap is left between the inner side of the stationary ring (4) and the main shaft (2); A sealing end cover (5) is mounted on the housing (3), one end of the main shaft (2) passes through the sealing end cover (5), and a resistance spring (6) is installed between the sealing end cover (5) and the stationary ring (4). The resistance spring (6) provides an elastic resistance force in the axial direction of the stationary ring (4) and makes one end of the stationary ring (4) resist against the contact surface of the dynamic ring (1); The oil circulation mechanism (7) is installed on the housing (3) and forms a lubricating oil path with the lubricating space, and continuously supplies lubricating liquid to the lubricating space in a trickle form.

2. The nuclear main pump mechanical seal structure according to claim 1 is characterized in that: A convex ring (8) is constructed on the contact surface of the movable ring (1), and a plurality of arc-shaped convex plates (9) are installed in a circular array inside the convex ring (8) and around the axis of the movable ring (1) to form the lubrication space, with a gap between each arc-shaped convex plate (9), and the number of circles is not less than two, and the arc-shaped convex plates (9) of two adjacent circles are staggered, and the end faces of the convex ring (8) and the arc-shaped convex plates (9) are flush.

3. The nuclear main pump mechanical seal structure according to claim 1 is characterized in that: The static ring (4) has two oil delivery holes (10) arranged in a circular array on the end surface. The end of the oil delivery hole (10) away from the dynamic ring (1) is provided with a plug (11). The plug (11) is inserted into the sealing end cover (5) in a horizontally slidable manner. The sealing end cover (5) is symmetrically provided with two circulating oil paths (12). The two plugs (11) are respectively connected to the two circulating oil paths (12). The oil circulation mechanism (7) is connected to the two circulating oil paths (12).

4. The nuclear main pump mechanical seal structure according to claim 3 is characterized in that: The oil circulation mechanism (7) comprises an oil box (701) arranged on the housing (3); the upper end and the lower end of one side of the oil box (701) are both connected to oil delivery pipes (702); the two oil delivery pipes (702) are respectively connected to two circulating oil circuits (12); a power component (14) is installed on one of the oil delivery pipes (702); and the lubricating liquid in the oil box (701) is transported to the corresponding oil delivery pipe (702) through the power component (14).

5. The nuclear main pump mechanical seal structure according to claim 4 is characterized in that: The power member (14) comprises a mounting tube (1401) mounted on the housing (3); a trigger rod (1402) is elastically and slidably inserted at one end of the mounting tube (1401); a free end of the trigger rod (1402) abuts against the outer peripheral side of the moving ring (1); when the moving ring (1) vibrates with a small amplitude during rotation, the trigger rod (1402) moves vertically with a small amplitude; a conversion mechanism (15) connected to the oil pipeline (702) is mounted on the mounting tube (1401); when the trigger rod (1402) moves, the conversion mechanism (15) converts the moving power of the trigger rod (1402) into oil transmission force.

6. The nuclear main pump mechanical seal structure according to claim 5 is characterized in that: The conversion mechanism (15) comprises a mounting box (1501) connected to the oil delivery pipe (702), a transmission gear (1502) being rotatably mounted in the mounting box (1501), a rotation axis of one of the transmission gears (1502) being located outside and being mounted with a rotating cylinder (1503), a driving plate (1504) being rotatably mounted in the mounting cylinder (1401), a wedge plate (1505) being vertically elastically slidably mounted on the top of the driving plate (1504), a plurality of wedge grooves (1506) for inserting the wedge plates (1505) being provided in a circular array at the bottom end of the rotating cylinder (1503), the plurality of wedge grooves (1506) forming an annular groove at the bottom of the rotating cylinder (1503), the driving plate (1504) being linked and matched with the trigger rod (1402), when the trigger rod (1402) moves back and forth, the driving plate (1504) is reciprocatingly rotated around its own axis.

7. The nuclear main pump mechanical seal structure according to claim 6 is characterized in that: An actuator rod (16) is vertically slidably installed in the installation cylinder (1401); a conversion hole (17) is provided through the axis of the drive plate (1504); a spiral groove (18) is provided in an annular manner on the inner circumference of the conversion hole (17); a guide plate (19) located in the spiral groove (18) is configured on the outer side of the actuator rod (16); the actuator rod (16) is connected to the trigger rod (1402) in a non-contact transmission manner; when the trigger rod (1402) moves slightly, the actuator rod (16) moves more significantly than the trigger rod (1402).

8. The nuclear main pump mechanical seal structure according to claim 7 is characterized in that: A clamping plate (20) is slidably mounted on the mounting tube (1401), a clamping spring (21) is installed between the clamping plate (20) and the mounting tube (1401), one end of the clamping plate (20) abuts against one end of the actuating rod (1402), a connecting rod (22) is coaxially constructed on the clamping plate (20), and the connecting rod (22) is connected to the actuator rod (16) in a non-contact transmission manner.

9. The nuclear main pump mechanical seal structure according to claim 8 is characterized in that: The installation cylinder (1401) has a small diameter cavity (23) and a large diameter cavity (24), the actuator rod (16) is slidably inserted in the small diameter cavity (23), and the end of the connecting rod (22) away from the trigger rod (1402) is configured with a push plate (13) located in the large diameter cavity (24), the large diameter cavity (24) and the small diameter cavity (23) are connected to each other, and a sealing area is formed between the push plate (13) and the actuator rod (16).

10. The nuclear main pump mechanical seal structure according to claim 5, characterized in that: One end of the trigger rod (1402) is an outer arc surface, the oil box (701) is annular, and two filter plates (25) are installed in the oil box (701). The two filter plates (25) divide the interior of the oil box (701) into two upper and lower areas.

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