Mechanical seal for rotor pump

Abstract

The utility model provides a mechanical seal for a rotor pump, which comprises a sealing seat, a main static ring and an auxiliary static ring are respectively assembled at two ends of the inner side of the sealing seat along the axial direction in a sliding way, an auxiliary moving ring is assembled on the outer wall of one end of a rotating shaft close to the auxiliary static ring, and the end surfaces of the auxiliary moving ring and the auxiliary static ring are butted in a relatively rotating way along the circumferential direction to form an auxiliary seal; a driving ring is assembled on the rotor at the other end of the rotating shaft and at one end close to the sealing seat, and the driving ring and the end face of the main static ring can relatively and rotatably abut against each other in the circumferential direction to form main sealing; a liquid inlet channel and a liquid outlet channel are formed in the side wall of the sealing seat, the inner end of the liquid inlet channel is close to the main seal, and the inner end of the liquid outlet channel is close to the auxiliary seal; the driving ring and the main static ring are both made of hard alloy materials, and the auxiliary moving ring and the auxiliary static ring are both made of silicon carbide materials. The mechanical seal for the rotor pump is simple in structure, convenient to install, stable in sealing performance and long in service life.

Description

Technical Field

[0001] The utility model relates to the technical field of mechanical seals, in particular to a mechanical seal for a rotor pump. Background Art

[0002] The rotary pump is a widely used positive displacement pump with strong self-priming and high head. Its reliable and robust structure allows it to transport a variety of viscous or particulate media. Rotary pumps are also highly efficient, energy-efficient, and time-saving, requiring no drainage or priming, making them suitable for a variety of complex fluids. They also offer smooth operation, self-priming, wear resistance, and resistance to clogging, resulting in low maintenance costs.

[0003] Common shaft seal types for rotary pumps include packing seals and mechanical seals. While packing seals are easy to assemble, replace, and cost-effective, they suffer from insufficient sealing performance, a short service life, and limited applicability. With the continuous advancement of mechanical seal technology, however, they have become the primary seal option for rotary pumps.

[0004] With the rapid development of the new energy vehicle industry, lithium batteries are increasingly being used, placing increasingly stringent demands on their production processes. NMP is an essential adhesive in lithium battery production. However, due to its maximum viscosity of 2000 cps and carbon black particle size of 30 nm, the high viscosity of NMP is accompanied by a high particle content and strong tinting strength, making it difficult to disperse.

[0005] The existing traditional rotor pump mechanical seal structure is usually difficult to apply to the media in the above-mentioned special working conditions. For example, the medium viscosity is too high, which makes the sealing surface easy to attract. When the machine is turned on and off, the high viscosity medium will increase the operating torque of the mechanical seal. At the same time, particulate matter in the medium can easily cause wear of the sealing surface, resulting in insufficient sealing performance and reducing the service life of the mechanical seal. Utility Model Content

[0006] In order to overcome at least one of the above defects in the prior art, the utility model provides a mechanical seal for a rotor pump, which has a simple structure, is easy to install, has stable sealing performance, and has a long service life.

[0007] The utility model provides a mechanical seal for a rotor pump: it comprises a sealing seat mounted on the outside of a rotating shaft, and the two ends of the inner side of the sealing seat are respectively slidably equipped with a main static ring and a secondary static ring in the axial direction, and the outer wall of the rotating shaft near one end of the secondary static ring is equipped with a secondary dynamic ring, and the secondary dynamic ring and the end face of the secondary static ring are rotatably abutted relative to each other in the circumferential direction to form a secondary seal; an active ring is equipped on the rotor at the other end of the rotating shaft and near one end of the sealing seat, and the active ring and the end face of the main static ring are rotatably abutted relative to each other in the circumferential direction to form a primary seal; a liquid inlet channel and a liquid outlet channel are provided on the side wall of the sealing seat, and the inner end of the liquid inlet channel is close to the main seal, and the inner end of the liquid outlet channel is close to the secondary seal; the active ring and the main static ring are both made of cemented carbide, and the secondary dynamic ring and the secondary static ring are both made of silicon carbide.

[0008] Compared with the prior art, the mechanical seal for a rotor pump of the utility model has the following advantages:

[0009] The mechanical seal structure for the rotor pump of the present invention adopts a double-end face structure, that is, the entire sealing system includes a main seal and a secondary seal, and the active ring of the main seal is directly mounted on the rotor, and the secondary dynamic ring of the secondary seal is directly mounted on the rotating shaft, which effectively simplifies the structural form of the overall seal, reduces the difficulty of installation and production cost; in addition, a liquid inlet channel and a liquid outlet channel are opened on the side wall of the sealing seat to realize the circulation of the isolation liquid in the sealing cavity, wherein the pressure of the isolation liquid is greater than the pressure at the medium end, to avoid the medium from leaking from the main sealing surface to the sealing cavity, and the isolation liquid also has another function of forming a liquid film at the grinding surface of the main seal and the secondary seal to realize dynamic sealing; more What is important is that the isolation fluid can carry away the friction heat of the sealing surface during the circulation process, thereby avoiding thermal deformation of the sealing surface and increasing the service life of the seal. On the other hand, the active ring and the main static ring in the utility model are both made of cemented carbide. The pairing of cemented carbide to cemented carbide is corrosion-resistant and resistant to high-viscosity shear forces, and will not cause the active static ring to tear. At the same time, even if particulate matter enters the sealing surface, it will be ground and will not damage the sealing surface of the main seal. It can effectively cope with complex working conditions with high viscosity and particulate matter. The secondary seal adopts silicon carbide to carbon ring silicon pairing, plus isolation fluid, to ensure the closing force of the mechanical seal, and at the same time, the sealing surface of the secondary seal will not be damaged by leaked particulate matter.

[0010] As an improvement, a first mounting groove and a second mounting groove are respectively provided at both ends of the inner cavity of the sealing seat, and the main static ring and the auxiliary static ring are respectively axially slidably mounted in the first mounting groove and the second mounting groove, and a first sealing ring is mounted between the outer wall of the main static ring and the inner wall of the first mounting groove, and between the outer wall of the auxiliary static ring and the inner wall of the second mounting groove; the inner end of the liquid inlet channel is connected to the bottom of the first mounting groove, and the inner end of the liquid outlet channel is connected to the bottom of the second mounting groove.

[0011] As a further improvement, a first elastic compensating member and a second elastic compensating member are respectively provided between the bottom of the first mounting groove and the tail end of the primary static ring and between the bottom of the second mounting groove and the tail end of the secondary static ring.

[0012] Preferably, the first elastic compensating part and the second elastic compensating part have the same structure and both include multiple cylindrical springs. The bottom of the first mounting groove and the bottom of the second mounting groove are both provided with multiple spring holes. One end of each of the cylindrical springs is respectively fitted and positioned in the corresponding spring hole, and the other end is abutted against the tail end of the main static ring or the tail end of the secondary static ring.

[0013] Further improved, a connecting hole is provided at the bottom of the first mounting groove and passes through to the bottom of the second mounting groove, and anti-rotation pins are installed at both ends of the connecting hole. The tail end of the main static ring and the tail end of the secondary static ring are respectively provided with anti-rotation pin grooves for corresponding anti-rotation pins.

[0014] As a further improvement, a third mounting groove is provided inwardly at one end of the rotor close to the sealing seat, one end of the active ring is fitted in the third mounting groove, a first transmission pin is provided at the bottom of the third mounting groove, and a first transmission pin groove is provided at the tail end of the active ring to be fitted with the first transmission pin.

[0015] Further improved, a first annular groove is provided on the radial outer wall of the active ring, and a second sealing ring is installed in the first annular groove; a second annular groove is provided on the outer wall of the rotating shaft at a position corresponding to the radial inner wall of the active ring, and a third sealing ring is installed in the second annular groove.

[0016] Further improvement is that an annular mounting boss is formed on the outer peripheral wall of one end of the rotating shaft, and a fourth mounting groove is provided at the end of the mounting boss near the sealing seat, the auxiliary dynamic ring is mounted in the fourth mounting groove, and a fourth sealing ring is mounted between the auxiliary dynamic ring and the fourth mounting groove; two second transmission pins symmetrically distributed along its axis are provided on the outer peripheral wall of the mounting boss, and two second transmission pin grooves are provided at the tail end of the auxiliary dynamic ring, which are respectively equipped with two second transmission pins.

[0017] Preferably, the main static ring and the auxiliary static ring have the same structure.

[0018] The various improvements and advantages of the present invention will be described in the following detailed description, and in part will become apparent from the description, or understood by practicing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1This is a cross-sectional view of the mechanical seal for the rotor pump of the present utility model;

[0020] Figure 2 This is a cross-sectional view from another angle of the mechanical seal for the rotor pump of the present invention;

[0021] Figure 3 This is a structural diagram of the sealing seat in the present utility model;

[0022] Figure 4 This is a structural diagram of the sealing seat in the utility model from another angle.

[0023] Description of reference numerals:

[0024] 1. Sealing seat; 2. Main static ring; 3. Auxiliary static ring; 4. Auxiliary dynamic ring; 5. Rotor; 6. Active ring; 7. Liquid inlet channel; 8. Liquid outlet channel; 9. First mounting groove; 10. Second mounting groove; 11. First sealing ring; 12. Cylindrical spring; 13. Spring hole; 14. Connecting hole; 15. Anti-rotation pin; 16. Anti-rotation pin groove; 17. Third mounting groove; 18. First transmission pin; 19. First transmission pin groove; 20. Second sealing ring; 21. Third sealing ring; 22. Mounting boss; 23. Fourth mounting groove; 24. Fourth sealing ring; 25. Second transmission pin; 26. Second transmission pin groove. DETAILED DESCRIPTION

[0025] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of the present application and are not intended to limit the scope of protection of the embodiments of the present application. Those skilled in the art may adjust them as needed to suit specific application scenarios.

[0026] In the description of the embodiments of this application, it should be noted that, unless otherwise specified or limited, the terms "fixed" and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on the specific circumstances.

[0027] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] See also Figures 1 to 4As shown, the embodiment of the present application discloses a mechanical seal for a rotor pump, which includes a sealing seat 1 that is sleeved on the outside of the rotor pump, and the outer peripheral flange surface of the sealing seat 1 is connected to the base of the rotor pump, and a main static ring 2 and a secondary static ring 3 are respectively axially slidably mounted on both ends of the radial inner side of the sealing seat 1; in addition, a secondary dynamic ring 4 is mounted on the outer wall of one end of the rotating shaft near the secondary static ring 3, and the secondary dynamic ring 4 and the end face of the secondary static ring 3 are circumferentially rotatable relative to each other to form a secondary seal; a rotor 5 is mounted on the outside of the other end of the rotating shaft, and an active ring 6 is mounted on the rotor 5 and on one end close to the sealing seat 1, and the active ring 6 is axially slidable against the end face of the main static ring 2 The surfaces can be relatively rotatable in the circumferential direction to form a main seal; a complete sealing cavity is formed between the radial inner wall of the sealing seat 1 and the outer wall of the rotating shaft as well as the main seal and the auxiliary seal, wherein the outer side of the main seal is the medium end, and the outer side of the secondary seal is the atmosphere end. The sealing cavity is used to pass the isolation liquid, wherein the pressure of the isolation liquid is greater than the pressure at the medium end to prevent the medium from leaking from the main sealing surface to the sealing cavity. The isolation liquid also has another function of forming a liquid film at the grinding surface of the main seal and the auxiliary seal to achieve dynamic sealing; more importantly, the isolation liquid can carry the friction heat of the sealing surface during the circulation process to avoid thermal deformation of the sealing surface and increase the service life of the seal.

[0029] In this structure, in order to ensure good circulation of the isolation liquid in the sealing cavity, a liquid inlet channel 7 and a liquid outlet channel 8 are provided on the side wall of the sealing seat 1. Here, the liquid inlet channel 7 and the liquid outlet channel 8 both include a radial channel extending radially along the sealing seat 1, and an axial channel extending axially, and the inner end of the liquid inlet channel 7 is close to the main seal, and the inner end of the liquid outlet channel 8 is close to the secondary seal. The vertical angle of the liquid inlet channel 7 allows the low-temperature isolation liquid entering from the outside to be flushed to the sealing grinding surface of the main seal first, and then pass through the sealing cavity to flush the sealing grinding surface of the secondary seal, and finally flow out from the liquid outlet channel 8. Since the outer side of the main seal is in direct contact with the medium end, there is a possibility that the medium may enter the inner side wall from the outer side wall of the main sealing surface during the operation of the main sealing surface. The isolation liquid first flushes the main sealing surface, which can quickly and timely flush away the medium, and can also cool the main seal in the first place, so that the medium accumulates on the main sealing surface over the years, affecting the sealing performance and service life.

[0030] On the other hand, in this embodiment, the active ring 6 and the main static ring 2 are both made of cemented carbide. The pairing of cemented carbide to cemented carbide is corrosion-resistant and resistant to high-viscosity shear forces, and will not cause the active static ring to tear. At the same time, even if particulate matter enters the sealing surface, it will be ground and will not damage the sealing surface of the main seal, which can effectively cope with high viscosity and complex working conditions containing particulate matter. More specifically, in this structure, the sealing surface widths of the active ring 6 and the main static ring 2 are the same, but the polishing process is different, which can ensure that the main sealing surface of the mechanical seal will not increase the startup torque due to the adsorption of the sealing ring surface.

[0031] Similarly, the auxiliary dynamic ring 4 and the auxiliary static ring 3 are both made of silicon carbide. The secondary seal uses silicon carbide to carbon ring silicon pairing, plus isolation fluid to ensure the closing force of the mechanical seal, while also preventing the leaked particles from damaging the sealing surface of the secondary seal.

[0032] In the above structure, it is further preferred that the main static ring 2 and the auxiliary static ring 3 have completely the same structural form, which saves processing costs. In an emergency, the two can be interchangeable.

[0033] See attached Figure 2 In this embodiment, a first mounting groove 9 and a second mounting groove 10 are respectively provided at both ends of the inner cavity of the sealing seat 1. The main static ring 2 and the auxiliary static ring 3 are respectively slidably mounted in the first mounting groove 9 and the second mounting groove 10 along the axial direction, and a first sealing ring 11 is mounted between the outer wall of the main static ring 2 and the inner wall of the first mounting groove 9 and between the outer wall of the auxiliary static ring 3 and the inner wall of the second mounting groove 10; the inner end of the liquid inlet channel 7 is connected to the bottom of the first mounting groove 9, and the inner end of the liquid outlet channel 8 is connected to the bottom of the second mounting groove 10. This design facilitates the processing of the axial channel and reduces the processing difficulty and production cost.

[0034] For more details, see the attached Figure 2 、 3 4. In this embodiment, a first elastic compensating member and a second elastic compensating member are respectively provided between the bottom of the first mounting groove 9 and the tail end of the primary static ring 2, and between the bottom of the second mounting groove 10 and the tail end of the secondary static ring 3. Preferably, the first elastic compensating member and the second elastic compensating member have the same structure, both comprising a plurality of cylindrical springs 12. The bottom of the first mounting groove 9 and the bottom of the second mounting groove 10 are both provided with a plurality of spring holes 13. One end of each cylindrical spring 12 is respectively fitted into a corresponding spring hole 13, and the end of each cylindrical spring 12 abuts against the bottom of the spring hole 13. The other end of each cylindrical spring 12 abuts against the tail end of the primary static ring 2 or the tail end of the secondary static ring 3, thereby achieving elastic compensation for the primary static ring 2 or the secondary static ring 3. In this structure, both the primary and secondary sealing parts adopt the static ring compensation form, that is, after the sealing surface is worn, the wear amount is compensated by the axial displacement of the static ring end, ensuring that the sealing surface is always in contact. Specifically, a corresponding cylindrical spring 12 is arranged between the tail end of the sub-main static ring 2, the auxiliary static ring 3 and the sealing seat 1. Because the static ring and the sealing seat 1 are stationary, the elastic compensation part is also stationary, thereby ensuring better tracking between the main static ring 2 or the auxiliary static ring 3 and the cylindrical spring, further ensuring the stability of the compensation performance and the sealing performance.

[0035] Furthermore, in this embodiment, a connecting hole 14 is formed at the bottom of the first mounting groove 9 and extends through to the bottom of the second mounting groove 10. Anti-rotation pins 15 are fitted at both ends of the connecting hole 14. Anti-rotation pin slots 16 for receiving corresponding anti-rotation pins 15 are also provided at the rear ends of the primary and secondary static rings 2 and 3. In this structure, the anti-rotation pins 15 primarily prevent circumferential rotation of the primary and secondary static rings 2 and 3, thereby affecting sealing performance. Furthermore, the anti-rotation pins 15 within the first and second mounting grooves 9 and 10 are coaxially arranged. This simplifies the process by simply machining a connecting hole at the corresponding location on the sealing seat 1, with both ends connecting to the first and second mounting grooves 9 and 10, respectively. The corresponding anti-rotation pins 15 are then installed at both ends. This greatly facilitates processing and reduces manufacturing costs.

[0036] In this embodiment, a third mounting groove 17 is provided in a concave shape at one end of the rotor 5 near the sealing seat 1. One end of the active ring 6 is fitted into the third mounting groove 17. A first transmission pin 18 is provided at the bottom of the third mounting groove 17. A first transmission pin groove 19, which is fitted with the first transmission pin 18, is provided at the tail end of the active ring 6. A first annular groove is provided on the radial outer wall of the active ring 6, and a second sealing ring 20 is fitted in the first annular groove. A second annular groove is provided on the outer wall of the rotating shaft at a position corresponding to the radial inner wall of the active ring 6, and a third sealing ring 21 is fitted in the second annular groove. The provision of the third sealing ring 21 ensures the stability of the dynamic ring on the one hand, prevents flushing liquid from entering the cam and causing impact on the cam on the other hand, and prevents leakage of the medium.

[0037] See the attached Figure 2 On the other hand, an annular mounting boss 22 is formed on the outer peripheral wall of the rotating shaft at the end away from the rotor 5. A fourth mounting groove 23 is provided on the end of the mounting boss 22 near the sealing seat 1. The auxiliary dynamic ring 4 is mounted in the fourth mounting groove 23, and a fourth sealing ring 24 is installed between the auxiliary dynamic ring 4 and the fourth mounting groove 23. Two second drive pins 25 are symmetrically distributed along the axis of the mounting boss 22. The rear end of the auxiliary dynamic ring 4 is provided with two second drive pin grooves 26, which respectively match the two second drive pins 25. In this structure, the auxiliary dynamic ring 4 is directly mounted on the outer wall of the rotating shaft, without the need for other structures, simplifying the overall structure of the mechanical seal, facilitating installation, and reducing costs.

[0038] In the description of this application, the description with reference to the terms "this embodiment", "some embodiments", etc. means that the specific features, mechanisms, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, mechanisms, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are mutually inconsistent.

[0039] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A mechanical seal for a rotor pump, characterized in that: The invention comprises a sealing seat (1) which is fitted on the outside of a rotating shaft, wherein the two ends of the inner side of the sealing seat (1) are respectively equipped with a main static ring (2) and a secondary static ring (3) which can slide in the axial direction, and an auxiliary dynamic ring (4) is equipped on the outer wall of the rotating shaft near one end of the secondary static ring (3), and the secondary dynamic ring (4) and the end face of the secondary static ring (3) are relatively rotatable along the circumferential direction to form a secondary seal; an active ring (6) is equipped on the rotor (5) at the other end of the rotating shaft and near one end of the sealing seat (1). The active ring (6) and the end face of the main static ring (2) are rotatably contacted with each other in the circumferential direction to form a main seal; a liquid inlet channel (7) and a liquid outlet channel (8) are provided on the side wall of the sealing seat (1), and the inner end of the liquid inlet channel (7) is close to the main seal, and the inner end of the liquid outlet channel (8) is close to the secondary seal; the active ring (6) and the main static ring (2) are both made of cemented carbide, and the secondary active ring (4) and the secondary static ring (3) are both made of silicon carbide.

2. The mechanical seal for a rotor pump according to claim 1, characterized in that: A first mounting groove (9) and a second mounting groove (10) are respectively provided at both ends of the inner cavity of the sealing seat (1); the main static ring (2) and the auxiliary static ring (3) are respectively axially slidably mounted in the first mounting groove (9) and the second mounting groove (10); and a first sealing ring (11) is mounted between the outer wall of the main static ring (2) and the inner wall of the first mounting groove (9) and between the outer wall of the auxiliary static ring (3) and the inner wall of the second mounting groove (10); the inner end of the liquid inlet channel (7) is connected to the bottom of the first mounting groove (9), and the inner end of the liquid outlet channel (8) is connected to the bottom of the second mounting groove (10).

3. The mechanical seal for a rotor pump according to claim 2, characterized in that: A first elastic compensating member and a second elastic compensating member are respectively provided between the bottom of the first mounting groove (9) and the tail end of the primary static ring (2), and between the bottom of the second mounting groove (10) and the tail end of the secondary static ring (3).

4. The mechanical seal for a rotor pump according to claim 3, characterized in that: The first elastic compensating member and the second elastic compensating member have the same structure and both include a plurality of cylindrical springs (12). The bottom of the first mounting groove (9) and the bottom of the second mounting groove (10) are both provided with a plurality of spring holes (13). One end of each cylindrical spring (12) is respectively fitted and positioned in the corresponding spring hole (13), and the other end is in contact with the tail end of the main static ring (2) or the tail end of the auxiliary static ring (3).

5. The mechanical seal for a rotor pump according to claim 2, characterized in that: A connecting hole (14) is provided at the bottom of the first mounting groove (9) and extends to the bottom of the second mounting groove (10). Anti-rotation pins (15) are installed at both ends of the connecting hole (14). Anti-rotation pin grooves (16) for installing corresponding anti-rotation pins (15) are provided at the tail end of the main static ring (2) and the tail end of the auxiliary static ring (3).

6. The mechanical seal for a rotor pump according to claim 1, characterized in that: A third mounting groove (17) is provided in a concave shape at one end of the rotor (5) close to the sealing seat (1), one end of the active ring (6) is fitted into the third mounting groove (17), a first transmission pin (18) is provided at the bottom of the third mounting groove (17), and a first transmission pin groove (19) for fitting with the first transmission pin (18) is provided at the tail end of the active ring (6).

7. The mechanical seal for a rotor pump according to claim 6, characterized in that: A first annular groove is provided on the radial outer wall of the active ring (6), and a second sealing ring (20) is fitted in the first annular groove; a second annular groove is provided on the outer wall of the rotating shaft at a position corresponding to the radial inner wall of the active ring (6), and a third sealing ring (21) is fitted in the second annular groove.

8. The mechanical seal for a rotor pump according to claim 1, characterized in that: An annular mounting boss (22) is formed on the outer peripheral wall of one end of the rotating shaft, and a fourth mounting groove (23) is provided at one end of the mounting boss (22) near the sealing seat (1). The auxiliary dynamic ring (4) is mounted in the fourth mounting groove (23), and a fourth sealing ring (24) is mounted between the auxiliary dynamic ring (4) and the fourth mounting groove (23); two second transmission pins (25) symmetrically distributed along the axis are provided on the outer peripheral wall of the mounting boss (22), and two second transmission pin grooves (26) are provided at the tail end of the auxiliary dynamic ring (4) to be respectively equipped with the two second transmission pins (25).

9. The mechanical seal for a rotor pump according to any one of claims 1 to 8, characterized in that: The main static ring (2) and the auxiliary static ring (3) have the same structure.

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