A stirring shaft sealing device

Abstract

The application discloses a stirring shaft sealing device, which belongs to the technical field of sealing and comprises a sealing cavity formed by combination of an upper sealing cylinder and a lower sealing cylinder, wherein a stirring shaft of a stirring tank penetrates through the sealing cavity; a central positioning cylinder is arranged at the lower part of the lower sealing cylinder, the bottom of the central positioning cylinder is provided with a mounting hole for the stirring shaft to penetrate through, and a damping sealing assembly composed of a shaft chuck, a damping connecting piece, a dynamic sealing disc and a static sealing disc is further arranged in the sealing cavity; a closed cavity is formed between the damping sealing assembly and the central positioning cylinder, the closed cavity and the sealing cavity are in communication with each other and filled with lubricating oil. The application has a triple sealing mechanism of mechanical dynamic sealing of the dynamic and static sealing disc structure, sealing of sealing liquid and packing sealing cavity structure, and has better sealing effect compared with the traditional liquid sealing device, low production and maintenance cost, and eliminates potential environmental safety and health risks such as field pollution and poisoning.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sealing, in particular to a stirring shaft sealing device. BACKGROUND

[0002] The existing stirring shaft of a stirring tank usually needs to be provided with a sealing device to ensure the air tightness of the tank body, avoid external gas from entering the tank body to affect the reaction in the tank, prevent harmful and polluting gas in the tank from overflowing from the stirring shaft to pollute the surrounding environment and harm the health of workers. At present, the sealing form of the stirring shaft of the stirring tank is usually a traditional liquid sealing device, and common liquid media include water, lubricating oil, mercury, etc. In actual production and application, the above-mentioned liquid media are consumables and need to be added according to the consumption amount frequently, which has high maintenance cost, and the volatilized liquid media pollute the on-site environment and have great safety risks in the production site. Especially in some application scenarios with high sealing requirements, only high-density mercury sealing can be used, but the volatilized mercury vapor of the mercury sealing is highly toxic, which has great safety risks in the production site. According to relevant national laws and regulations, the production, transportation and use of mercury have been listed as national controlled substances. Therefore, the mercury sealing is not suitable for the shaft sealing in the industry. SUMMARY

[0003] The present application aims at solving the above-mentioned problems and provides a stirring shaft sealing device with good sealing effect, low maintenance cost and no pollution.

[0004] In order to solve the above-mentioned technical problems, the present application adopts the following technical scheme:

[0005] The application relates to a stirring shaft sealing device, which comprises a sealing flange, upper and lower fixed sealing cylinders arranged above and below the sealing flange respectively, the lower sealing cylinder is arranged on a stirring tank top cover, and the upper and lower sealing cylinders are combined to form a sealing chamber through which a stirring shaft can penetrate; a center positioning cylinder is arranged in the sealing chamber and sleeved on the stirring shaft, the center positioning cylinder is located at the lower part of the sealing chamber and extends upwards, a fixed flange is connected to the bottom of the center positioning cylinder, the fixed flange is located between the stirring tank top cover and the lower sealing cylinder base, and the fixed flange is fixedly connected with the stirring tank top cover and the lower sealing cylinder base; an installation hole through which the stirring shaft penetrates is arranged at the bottom of the center positioning cylinder; the structural feature is that a damping sealing assembly is further arranged in the sealing chamber, the damping sealing assembly comprises a shaft chuck arranged above the center positioning cylinder, the shaft chuck is connected with the stirring shaft and rotationally abuts against the stirring shaft; a static sealing disc is arranged in the sealing chamber and located between the lower sealing cylinder and the center positioning cylinder, the inner and outer sides of the static sealing disc respectively abut against the center positioning cylinder and the lower sealing cylinder, and the bottom surface of the static sealing disc abuts against the lower sealing cylinder base; a dynamic sealing disc is arranged above the static sealing disc, the dynamic sealing disc is sleeved outside the center positioning cylinder and rotationally connected with the static sealing disc, and the shaft chuck and the dynamic sealing disc are elastically connected through a damping connecting piece; when the stirring shaft rotates, the shaft chuck, the damping connecting piece and the dynamic sealing disc synchronously rotate with the stirring shaft; a closed cavity is formed between the shaft chuck, the damping connecting piece, the dynamic sealing disc and the center positioning cylinder, and the closed cavity is filled with lubricating oil to prevent the gas in the stirring tank from communicating with the outside.

[0006] Further, the inner diameter of the center positioning cylinder is 15-20mm larger than the diameter of the stirring shaft, so that the stirring shaft can easily penetrate through the center positioning cylinder, the assembly difficulty is reduced, and the cylinder wall of the center positioning cylinder is far away from the lateral swing range of the stirring shaft, so that knocking and scratching are avoided.

[0007] Further, the damping connecting piece is made of fluorine rubber or polytetrafluoroethylene material.

[0008] Further, a plurality of annular sealing grooves are arranged on the inner side wall of the shaft chuck and spaced along the circumference of the stirring shaft, and the annular sealing grooves are filled with fillers, such as O-shaped rubber rings, raw material belts and 1596 silicone sealants, so as to further enhance the sealing effect between the shaft chuck and the stirring shaft.

[0009] Further, a plurality of grooves are arranged on the bottom surface of the static sealing disc and spaced, and a convex nut is arranged on the lower sealing cylinder base and can be embedded in the groove on the bottom surface of the static sealing disc, so as to be locked, preferably, the static sealing disc is made of fluorine rubber or polytetrafluoroethylene material, so as to improve the high temperature resistance, self-lubricating wear resistance and corrosion resistance.

[0010] Further, the upper sealing cylinder and the lower sealing cylinder are assembled cylinder bodies, facilitating disassembly and installation during later maintenance, and preferably, the upper sealing cylinder and the lower sealing cylinder are longitudinally symmetrically divided into a first cylinder body and a second cylinder body, and the first cylinder body and the second cylinder body are sealingly connected through flanges to form a sealing chamber.

[0011] Further, a packing gland is arranged between the top cover of the upper sealing cylinder and the stirring shaft, the bottom of the packing gland is provided with an annular convex edge extending transversely to the stirring shaft, an upper sealing cavity is formed between the packing gland, the annular convex edge and the stirring shaft, and the upper sealing cavity is filled with a packing ring, and a gland cover is arranged at the upper opening of the packing gland to compress the packing ring.

[0012] Further, the upper surface of the static sealing disc is a bowl-shaped groove, and the lower surface of the dynamic sealing disc is a bowl-shaped convex that cooperates with the static sealing disc, so that the dynamic sealing disc can be automatically adjusted to be centered during assembly, thereby ensuring the concentricity of the dynamic sealing disc and the static sealing disc after assembly; the shape of the contact surface of the dynamic sealing disc and the static sealing disc can be other shapes, such as triangular, rectangular, inverted conical, etc., as long as the concentricity during assembly can be ensured.

[0013] Further, a gap is left between the dynamic sealing disc and the center positioning cylinder, a sealing liquid passage is formed between the center positioning cylinder, the damping connecting piece, the dynamic sealing disc and the static sealing disc, the sealed cavity, the sealing liquid passage and the sealing chamber are connected to form a liquid sealing cavity, and the liquid sealing cavity is filled with lubricating oil, which is conducive to improving the lubrication of each component during relative rotation, reducing friction, reducing friction heat, and improving the sealing effect.

[0014] Further, the upper surface of the static sealing disc is further provided with an annular groove, the lower surface of the dynamic sealing disc is provided with an annular convex corresponding to the annular groove of the static sealing disc, the annular convex of the dynamic sealing disc is embedded in the annular groove of the static sealing disc to be mutually blocked, and the annular groove is filled with lubricating oil, which can further improve the sealing effect; more preferably, the annular groove of the static sealing disc is provided with a plurality of annular grooves, and the plurality of annular grooves are uniformly arranged on the upper surface of the static sealing disc.

[0015] Further, a stop ring is arranged around the dynamic sealing disc in the sealing chamber, and the stop ring provides axial positioning for the dynamic sealing disc.

[0016] Further, the damping sealing assembly further comprises a damping buffer, the damping buffer comprises a first pawl and a second pawl, the first pawl is fixedly connected with the shaft chuck, the second pawl is fixedly connected with the dynamic sealing disc, and the first pawl and the second pawl are elastically connected through an elastic element; the elastic element can be a spring or a rubber block or an air spring; as preferred, a plurality of damping buffers are provided, and the plurality of damping buffers are uniformly and symmetrically arranged around the stirring shaft, so that torque symmetry balance and uniform stress are achieved.

[0017] Further, roughness of contact surfaces of the center positioning cylinder, the lower sealing cylinder base, the sealing chamber side wall and the static sealing disc is 1.8-1.6 μm, so as to further improve the sealing effect.

[0018] Further, an observation window is arranged on the side wall of the sealing chamber, so that the running state of the sealing device can be observed, hidden troubles and sealing leakage can be found in time, and the equipment can be maintained.

[0019] After the above structure is adopted, the dynamic sealing disc and the static sealing disc form a mechanical dynamic sealing structure, the liquid sealing cavity formed by the closed cavity, the sealing liquid channel and the sealing chamber is filled with lubricating oil for sealing, the upper sealing cylinder and the stirring shaft are sealed through the packing sealing function, and good sealing effect is achieved through the triple sealing.

[0020] Compared with the prior art, the present application has the following beneficial effects.

[0021] The stirring shaft sealing device has the mechanical dynamic sealing of the dynamic and static sealing disc structure, the triple sealing mechanism of the sealing liquid sealing and the packing sealing function, and compared with the conventional liquid sealing device, the sealing effect is better, the production and maintenance cost is greatly reduced, and the potential environmental protection safety and health risks such as production site pollution and poisoning are completely eliminated. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The figure is a structural schematic view of the present application.

[0023] Figure 1 M: 1, sealing flange; 2, upper sealing cylinder; 3, lower sealing cylinder; 4, stirring tank top cover; 5, sealing chamber; 6, stirring shaft; 7, center positioning cylinder; 8, fixed flange; 9, elastic element; 10, shaft chuck; 11, static sealing disc; 12, dynamic sealing disc; 13, damping connecting piece; 14, packing function; 15, annular convex edge; 16, closed cavity; 17, lubricating oil; 18, annular sealing groove; 19, packing; 20, gland; 21, annular groove; 22, stop ring; 23, first pawl; 24, second pawl. DETAILED DESCRIPTION

[0024] To make the objectives, advantages, and features of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to facilitate and clearly illustrate the objectives of the embodiments of the present invention.

[0025] Reference Figure 1 A stirring shaft sealing device includes a sealing flange 1, with an upper sealing cylinder 2 and a lower sealing cylinder 3 fixed above and below the sealing flange 1, respectively. The lower sealing cylinder 3 is installed on the top cover 4 of the mixing tank. The upper sealing cylinder 2 and the lower sealing cylinder 3 are connected and combined to form a sealing chamber 5, through which the stirring shaft 6 can pass. A central positioning cylinder 7 is provided inside the sealing chamber 5, and the central positioning cylinder 7 is sleeved on the outside of the stirring shaft 6, that is, the stirring shaft 6 passes through the central positioning cylinder 7. The central positioning cylinder 7 is located at the lower part of the sealing chamber 5 and extends upward. Figure 1 As shown, the central positioning cylinder 7 extends upward to the sealing chamber 5 surrounded by the upper sealing cylinder 2, and a fixed flange 8 is connected to the bottom of the central positioning cylinder 7. Figure 1 As shown, the fixing flange 8 is located between the top cover 4 of the mixing tank and the base of the lower sealing cylinder 3, and the fixing flange 8 is fixedly connected to the top cover 4 of the mixing tank and the base of the lower sealing cylinder 3. Specifically, bolts can be used for the fixed connection. The lower sealing cylinder 3 refers to... Figure 1A horizontal plate is fixedly connected to the bottom of the vertical side wall of the lower sealing cylinder 3; the bottom of the central positioning cylinder 7 is provided with an installation hole through which the stirring shaft 6 can pass; the inner diameter of the central positioning cylinder 7 is 15mm-20mm larger than the diameter of the stirring shaft 6, so that the stirring shaft 6 can easily pass through the middle of the central positioning cylinder 7, reducing the assembly difficulty, and keeping the cylinder wall of the central positioning cylinder 7 away from the lateral swing range of the stirring shaft 6 to avoid bumping and scratching; a vibration damping sealing assembly is provided in the sealing chamber 5, which has the function of sealing and reducing the vibration of the sealing device during stirring. The vibration damping sealing assembly includes a shaft chuck 10, which is located above the central positioning cylinder 7 and is connected to the stirring shaft 6 and rotates in contact with the stirring shaft 6. The shaft chuck 10 consists of a pair of open disc clamps that engage with the stirring shaft 6. A static sealing disc 11 is located within the sealing chamber 5. This static sealing disc 11 is stationary and positioned between the lower sealing cylinder 3 and the central positioning cylinder 7. The inner and outer sides of the static sealing disc 11 abut against the central positioning cylinder 7 and the lower sealing cylinder 3, respectively, while the bottom surface of the static sealing disc 11 abuts against the base of the lower sealing cylinder 3. A dynamic sealing disc 12 is located above the static sealing disc 11. The dynamic sealing disc 12 is fitted around the outside of the central positioning cylinder 7 and rotatably connected to the static sealing disc 11. The shaft chuck 10 and the dynamic sealing disc 12 are elastically connected via a vibration-damping connector 13. When the stirring shaft 6 rotates, the shaft chuck 10, vibration-damping connector 13, and other components are connected. The dynamic sealing disc 12 rotates synchronously with the stirring shaft 6. The vibration damping connector 13 is made of fluororubber or polytetrafluoroethylene and serves to transmit torque to the dynamic sealing disc 12. Its flexibility also helps to offset and compensate for the lateral and longitudinal vibrations of the stirring shaft 6 during startup, operation, and shutdown, ensuring that the trajectory of the dynamic sealing disc 12 remains unchanged as it rotates around the central positioning cylinder 7. A sealed cavity 16 is formed between the shaft chuck 10, the vibration damping connector 13, the dynamic sealing disc 12, and the central positioning cylinder 7. The sealed cavity 16 is filled with lubricating oil 17 to prevent the gas inside the mixing tank from communicating with the outside. Several annular sealing grooves 18 are spaced apart on the inner wall of the shaft chuck 10. 8 is arranged around the circumference of the stirring shaft 6. The annular sealing groove 18 is filled with filler such as O-rings, PTFE tape, 1596 silicone sealant, etc., to further enhance the sealing effect between the shaft chuck 10 and the stirring shaft 6. The bottom surface of the static sealing disc 11 is provided with several grooves spaced apart. The base of the lower sealing cylinder 3 is provided with a protruding nut that can be embedded in the groove on the bottom surface of the static sealing disc 11 for locking. When the nut is inserted into the groove on the bottom surface of the static sealing disc 11, the position of the static sealing disc 11 is locked, thereby restricting the static sealing disc 11 from rotating with the stirring shaft 6. The static sealing disc 11 is made of fluororubber or polytetrafluoroethylene to improve its high temperature resistance, self-lubricating wear resistance and corrosion resistance.

[0026] Reference Figure 1A stuffing box 14 is provided between the top cover of the upper sealing cylinder 2 and the stirring shaft 6. The bottom of the stuffing box 14 has an annular flange 15, which extends laterally toward the stirring shaft 6. The stuffing box 14, the annular flange 15, and the stirring shaft 6 form an upper sealing cavity, which is filled with packing packing 19. A pressure cap 20 is provided at the upper opening of the stuffing box 14 to press the packing packing 19. Even if the packing packing 19 is worn, the air pressure in the mixing tank will push the lubricating oil 17 into the worn position, which plays a sealing role and meets the needs of long-term operation of the equipment. The upper sealing cylinder 2 and the lower sealing cylinder 3 can be assembled cylinders, which are convenient for disassembly and installation during later maintenance. For example, the upper sealing cylinder 2 and the lower sealing cylinder 3 can be longitudinally symmetrically divided into a first cylinder and a second cylinder. The first cylinder and the second cylinder are connected by a flange seal to form a sealing chamber 5. The upper surface of the static sealing plate 11 is a bowl-shaped groove, and the lower surface of the dynamic sealing plate 12 is a bowl-shaped protrusion that matches the static sealing plate 11. This allows the dynamic sealing plate 12 to automatically adjust and center itself during assembly, ensuring the concentricity of the dynamic sealing plate 12 and the static sealing plate 11 after assembly. In addition to the bowl shape, the contact surfaces of the dynamic sealing plate 12 and the static sealing plate 11 can also be other shapes, such as triangles, rectangles, inverted cones, etc., as long as concentricity during assembly can be ensured.

[0027] Reference Figure 1 A gap is left between the dynamic sealing disc 12 and the central positioning cylinder 7. A sealing fluid channel is formed between the central positioning cylinder 7, the vibration damping connector 13, the dynamic sealing disc 12, and the static sealing disc 11. The sealed cavity 16, the sealing fluid channel, and the sealing chamber 5 are connected to form a liquid sealing cavity, which is filled with lubricating oil 17. This helps to improve the lubrication of the various components during relative rotation, reduce friction, reduce frictional heat, and improve the sealing effect. An annular groove 21 is also provided on the upper surface of the static sealing disc 11. An annular protrusion corresponding to the annular groove 21 on the static sealing disc 11 is provided on the lower surface of the dynamic sealing disc 12. The annular protrusion on the dynamic sealing disc 12 is embedded in the annular groove 21 of the static sealing disc 11 to block each other and limit the rotation trajectory of the dynamic sealing disc 12. The annular groove 21 is filled with lubricating oil 17, which can further improve the sealing effect. Multiple annular grooves 21 are provided on the static sealing disc 11 and are evenly distributed on the upper surface of the static sealing disc 11. Figure 1 Two annular grooves 21 are provided in the middle, or three or other numbers can be designed; a stop ring 22 is provided in the sealing chamber 5. The stop ring 22 is arranged around the dynamic sealing disc 12. The stop ring 22 provides axial positioning for the dynamic sealing disc 12 to prevent upward axial movement when the dynamic sealing disc 12 suddenly rotates at the moment the stirring shaft 6 starts, which would cause the contact gap between the dynamic and static seals to increase and affect the sealing effect of the dynamic and static discs.

[0028] Reference Figure 1The vibration damping and sealing assembly also includes a vibration damping buffer, which includes a first pawl 23 and a second pawl 24. The first pawl 23 is fixedly connected to the shaft chuck 10, and the second pawl 24 is fixedly connected to the dynamic seal plate 12. The first pawl 23 and the second pawl 24 are elastically connected by an elastic element 9, which can be a spring, a rubber block, or an air spring. The pawl is a rigid part used to transmit torque, and its function is to transmit the torsional torque generated when the shaft chuck 10 rotates to the dynamic seal plate 12 through the vibration damping buffer. To prevent excessive torsional torque from causing torsional deformation of the vibration damping connector 13, and to protect the vibration damping connector 13 from being torn by excessive external force; multiple vibration damping buffers are provided, and are evenly and symmetrically arranged with the stirring shaft 6 as the axis, striving for torque symmetry and balance, and uniform force distribution; the first claw 23 and the second claw 24 are elastically connected by the elastic element 9. During assembly, the sealing contact stress between the dynamic sealing disc 12 and the static sealing disc 11 can be adjusted by pre-tightening or loosening the elastic element 9, ensuring the sealing reliability of the dynamic and static sealing mechanism. The roughness of the contact surfaces of the control center positioning cylinder 7, the lower sealing cylinder 3 base, the side wall of the sealing chamber 5 and the static sealing disc 11 is 1.8 to 1.6 μm, to further improve the sealing effect. An observation window (not shown in the figure) is provided on the side wall of the sealing chamber 5. Specifically, the observation window can be set on the side wall of the upper sealing cylinder 2, which facilitates the observation of the operating status of the sealing device, timely detection of potential faults and sealing leaks, and facilitates equipment inspection and maintenance.

[0029] The sealing performance of the stirring shaft sealing device provided by this invention is tested using the pre-ash tank, a commonly used component in the ammonia-soda process, as an example. The pre-ash tank is a closed reaction vessel with a stirring shaft. Its basic structure and principle are similar to a reaction kettle. During operation, the reactants inside the tank—namely, the preheated mother liquor (mainly ammonium chloride) and lime slurry (mainly calcium hydroxide)—are continuously stirred and mixed by the stirrer, resulting in a chemical reaction that converts bound ammonia into free ammonia. Part of the free ammonia vaporizes and precipitates inside the tank. This gaseous ammonia gas is extremely prone to leaking into the atmosphere through the gap between the tank lid and the stirring shaft, causing excessive ammonia nitrogen emissions, polluting the atmosphere, and resulting in material loss and waste. The sealing mechanism of the pre-ash tank's stirring mechanism often uses a traditional mercury seal. Mercury, as the sealing medium, is volatile and is a consumable in actual production applications, requiring frequent replenishment based on consumption, leading to high maintenance costs. Furthermore, the volatilized mercury vapor is highly toxic, posing a significant safety risk at the production site. According to relevant national laws and regulations, the production, transportation, and use of mercury have been listed as nationally controlled substances. Therefore, mercury sealing is no longer suitable for continued promotion in the alkali production industry.

[0030] The stirring shaft sealing device provided by the present invention is arranged according to Figure 1Pre-assembly is performed, but the outer shell and stuffing box are not installed. The fixing flange at the bottom of the central positioning cylinder is sealed with a blind flange. A seamless steel pipe, approximately 0.3m long and φ200mm in diameter, is used to create a stirring shaft, which is clamped onto the shaft chuck. The upper end of the steel pipe is blind-plugged with a steel plate, with one pre-installed interface for a pressure gauge, one for compressed air, and one for a safety valve. The pressure gauge is a vacuum pressure gauge with a range of -100KPa to +100KPa. An air compressor and a vacuum machine are used to provide the air source pressure and vacuum, respectively. Tables 1 and 2 below show the measured data from the simulation experiment:

[0031]

[0032]

[0033] The simulation data above clearly demonstrates that the sealing pressure of the stirring shaft sealing device of this invention is between -50KPa and 60KPa, while the normal operating pressure range of the pre-ash tank is between -30KPa and 15KPa. The sealing performance of this device exceeds the equipment requirements by nearly twice, fully meeting the equipment application needs. Replacing the traditional mercury sealing device with this device is entirely feasible, completely eliminating the use of mercury, greatly reducing production consumption and maintenance costs, and providing significant environmental, safety, health, and socio-economic benefits.

[0034] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0035] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

[0036] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A stirring shaft sealing device, comprising a sealing flange (1), wherein an upper sealing cylinder (2) and a lower sealing cylinder (3) are respectively fixed above and below the sealing flange (1), the lower sealing cylinder (3) is installed on the top cover (4) of a stirring tank, and the upper sealing cylinder (2) and the lower sealing cylinder (3) are combined to form a sealing chamber (5) through which the stirring shaft (6) can pass; a central positioning cylinder (7) is provided inside the sealing chamber (5) and sleeved outside the stirring shaft (6), the central positioning cylinder (7) is located at the lower part of the sealing chamber (5) and extends upward, a fixed flange (8) is connected to the bottom of the central positioning cylinder (7), the fixed flange (8) is located between the top cover (4) of the stirring tank and the base of the lower sealing cylinder (3), and the fixed flange (8) is fixedly connected to the top cover (4) of the stirring tank and the base of the lower sealing cylinder (3); the bottom of the central positioning cylinder (7) is provided with an installation hole for the stirring shaft (6) to pass through; characterized in that, The sealed chamber (5) is also equipped with a vibration damping sealing assembly, which includes a shaft chuck (10) disposed above the central positioning cylinder (7). The shaft chuck (10) is connected to the stirring shaft (6) and fits against the stirring shaft (6). The sealed chamber (5) is equipped with a static sealing plate (11) disposed between the lower sealing cylinder (3) and the central positioning cylinder (7). The inner and outer sides of the static sealing plate (11) abut against the central positioning cylinder (7) and the lower sealing cylinder (3) respectively. The bottom surface of the static sealing plate (11) abuts against the base of the lower sealing cylinder (3). Above the static sealing plate (11) is a... There is a dynamic sealing disc (12), which is sleeved outside the central positioning cylinder (7) and rotatably connected to the static sealing disc (11). The shaft chuck (10) and the dynamic sealing disc (12) are elastically connected by a vibration damping connector (13). When the stirring shaft (6) rotates, the shaft chuck (10), the vibration damping connector (13) and the dynamic sealing disc (12) rotate synchronously with the stirring shaft (6). A sealed cavity (16) is formed between the shaft chuck (10), the vibration damping connector (13), the dynamic sealing disc (12) and the central positioning cylinder (7), and the sealed cavity (16) is filled with lubricating oil (17).

2. The stirring shaft sealing device according to claim 1, characterized in that, The inner diameter of the central positioning cylinder (7) is 15mm-20mm larger than the diameter of the stirring shaft (6).

3. The stirring shaft sealing device according to claim 1, characterized in that, The inner wall of the shaft chuck (10) is provided with several annular sealing grooves (18) spaced apart along the circumference of the stirring shaft (6), and the annular sealing grooves (18) are filled with filler.

4. The stirring shaft sealing device according to claim 1, characterized in that, The bottom surface of the static sealing disc (11) is provided with several grooves spaced apart, and the base of the lower sealing cylinder (3) is provided with a protruding nut that can be embedded in the groove on the bottom surface of the static sealing disc (11) for locking.

5. The stirring shaft sealing device according to claim 1, characterized in that, A stuffing box (14) is provided between the top cover of the upper sealing cylinder (2) and the stirring shaft (6). The bottom of the stuffing box (14) is provided with an annular protrusion (15) extending laterally towards the stirring shaft (6). An upper sealing cavity is formed between the stuffing box (14), the annular protrusion (15) and the stirring shaft (6). The upper sealing cavity is filled with packing packing (19). A pressure cap (20) for pressing the packing packing (19) is provided at the upper opening of the stuffing box (14).

6. The stirring shaft sealing device according to claim 1, characterized in that, There is a gap between the dynamic sealing disc (12) and the central positioning cylinder (7). A sealing liquid channel is formed between the central positioning cylinder (7), the vibration damping connector (13), the dynamic sealing disc (12), and the static sealing disc (11). The sealed cavity (16), the sealing liquid channel, and the sealing chamber (5) are connected to form a liquid sealing cavity. The liquid sealing cavity is filled with lubricating oil (17).

7. The stirring shaft sealing device according to claim 6, characterized in that, The upper surface of the static sealing disc (11) is provided with an annular groove (21), and the lower surface of the dynamic sealing disc (12) is provided with an annular protrusion corresponding to the annular groove (21) on the static sealing disc (11). The annular protrusion on the dynamic sealing disc (12) is embedded in the annular groove (21) of the static sealing disc (11) to block each other. The annular groove (21) is filled with lubricating oil (17).

8. The stirring shaft sealing device according to claim 1, characterized in that, The sealed chamber (5) is provided with a stop ring (22) surrounding the dynamic sealing disc (12), and the stop ring (22) provides axial positioning for the dynamic sealing disc (12).

9. The stirring shaft sealing device according to claim 1, characterized in that, The vibration damping sealing assembly further includes a vibration damping buffer, which includes a first pawl (23) and a second pawl (24). The first pawl (23) is fixedly connected to the shaft chuck (10), and the second pawl (24) is fixedly connected to the dynamic sealing disc (12). The first pawl (23) and the second pawl (24) are elastically connected by an elastic element (9).

10. The stirring shaft sealing device according to claim 1, characterized in that, The sealed chamber (5) has an observation window on its side wall.

Images