A floating mechanical seal device for high-temperature equipment

Abstract

This invention discloses a floating mechanical seal device for high-temperature equipment, comprising a sealing seat assembly and a bushing that is rotatably fitted with the sealing seat assembly. A sealing cavity is formed between the sealing seat assembly and the bushing, and an air nozzle is connected to the sealing cavity. A spring seat, which is fixedly fitted with the bushing, is installed inside the sealing cavity. Floating sealing components are fitted between the two sides of the spring seat and the corresponding sidewalls of the sealing cavity. Using the floating mechanical seal device for high-temperature equipment of this application ensures the reliability and durability of the seal.

Description

Technical Field

[0001] This invention relates to the field of sealing technology, and more specifically to a floating mechanical seal device for high-temperature equipment. Background Technology

[0002] Currently, the most widely used anode materials are still the two main categories: natural graphite and artificial graphite. There are also composite graphite materials, whose properties fall between natural and artificial graphite, formed by doping natural graphite with other anode materials. The most crucial step in manufacturing artificial graphite anode materials for lithium-ion batteries is the carbonization process (at temperatures of 700℃ and above, repeatedly stirring and mixing graphene powder and pitch powder, causing the pitch powder to melt and coat the outer surface of the graphene particles). The key equipment for this process is a high-temperature reactor; for horizontal reactors, sealing both ends of the shaft is essential.

[0003] Existing mechanical seals or packing seals have the following problems: First, high-temperature resistance is a major issue; key components are prone to heat deformation and lack heat dissipation capabilities. Second, the temperature inside the reactor can reach 600℃ or even higher, which falls within the sensitization temperature range of austenitic stainless steel. Prolonged operation can easily cause the main shaft to bend and deform. Furthermore, the long span of the main shaft itself can lead to warping in the middle, resulting in large bending and running at the shaft end, thus affecting the reliability of the shaft end seal and even causing it to fail. In addition, conventional seals lack sufficient airtightness (current coating granulation processes operate under a slightly positive pressure of 0.3-0.4 MPa inside the reactor, requiring isolation from the outside environment). Conventional packing seals suffer from contamination issues and require frequent replacement, and are currently being phased out. Summary of the Invention

[0004] In view of this, the object of the present invention is to solve at least one of the above problems and provide a floating mechanical seal device for high-temperature equipment in order to ensure the reliability and durability of the seal.

[0005] The present invention solves the above problems through the following technical means:

[0006] This invention provides a floating mechanical seal device for high-temperature equipment, including a sealing seat assembly and a bushing that is rotatably and sealingly fitted with the sealing seat assembly. A sealing cavity is formed between the sealing seat assembly and the bushing. An air nozzle is connected to the sealing cavity. A spring seat that is fixedly fitted with the bushing is installed inside the sealing cavity. Floating sealing components are fitted between the two sides of the spring seat and the corresponding sidewalls of the sealing cavity.

[0007] Furthermore, the floating seal assembly includes a stationary ring, a stationary ring radial limiting ring, a rotating ring, and a push ring sequentially fitted onto the bushing. One side of the stationary ring is connected to the seal seat assembly via multiple circumferentially arranged stationary ring anti-rotation pins to achieve circumferential limiting between the two. The other side of the stationary ring is tightly fitted with the rotating ring, and the stationary ring and the stationary ring radial limiting ring are nested together. The side of the rotating ring away from the stationary ring is tightly fitted with the push ring, and the outer circumferential surface of the rotating ring is provided with multiple slots. The spring seat is integrally provided with a claw that engages with the slots. Multiple springs are circumferentially fitted between the side of the push ring away from the rotating ring and the corresponding side wall of the spring seat, and the spring seat is provided with spring mounting holes.

[0008] Furthermore, a gland sealing assembly is fitted at one end of the sealing seat assembly.

[0009] Furthermore, the gland sealing assembly includes a graphite packing and a gland, the graphite packing is sealed between the sealing seat assembly and the bushing, and the gland presses the graphite packing together and is fixedly assembled with the sealing seat assembly by the gland fixing screws.

[0010] Furthermore, the end of the sealing seat assembly away from the gland sealing assembly is equipped with a vortex-type leak-proof component.

[0011] Furthermore, the vortex-type leak-proof component includes an inner spiral sleeve and an outer spiral sleeve that are coaxially fitted together. The inner spiral sleeve is integrally connected to the sealing seat assembly, or is fixedly connected to the sealing seat assembly by an inner spiral sleeve fixing screw. The inner spiral sleeve and the outer spiral sleeve rotate in opposite directions.

[0012] Furthermore, the stationary ring is composed of two semi-circular stationary ring bodies assembled together. The two semi-circular stationary ring bodies are assembled and positioned by stationary ring assembly positioning pins, and are joined together as a whole by stationary ring clamps.

[0013] Furthermore, the moving ring is composed of two semi-circular moving ring bodies assembled together. The two semi-circular moving ring bodies are assembled and positioned by moving ring assembly positioning pins, and are joined together as a whole by moving ring clamps.

[0014] Furthermore, the sealing seat assembly includes a first sealing seat, a second sealing seat, and a third sealing seat that are assembled by bolted flange platform structure. Graphite sealing gaskets are installed at the mating assembly points of the first sealing seat and the second sealing seat, and at the mating assembly points of the second sealing seat and the third sealing seat.

[0015] Furthermore, both the first and second sealing seats are equipped with water-cooling jackets. The water-cooling jacket of the first sealing seat is connected to a first cooling water inlet and a first cooling water outlet; the water-cooling jacket of the second sealing seat is connected to a second cooling water inlet and a second cooling water outlet.

[0016] The beneficial effects of this invention are:

[0017] 1. This sealing device combines floating and mechanical sealing, with the floating seal adapting to shaft end warping. Furthermore, the sealing cavity has a certain degree of airtightness and pressure-holding capacity after a certain amount of gas is introduced, ensuring the pressure inside the sealing cavity is greater than the pressure inside the vessel, thus preventing material leakage and isolating it from external air. Real-time pressure monitoring of the sealing cavity allows for timely detection and plugging of leaks.

[0018] 2. Furthermore, the stationary ring is made of impregnated graphite material, which has high wear resistance and high temperature resistance. Its dense and airtight texture enables shaft end sealing under certain pressure, high temperature and dust environments. In addition, the outer surface of the bushing fitted with the stationary ring is nickel plated, resulting in extremely low wear and a longer service life.

[0019] 3. Furthermore, the stationary ring can float up and down on the bushing. The stationary ring floats up and down with the deformed bushing and the sealing surface fits (the deformation of the spindle will act on the bushing). The end face sealing surface is always held against by the stationary ring (this force comes from the spring and the air pressure in the sealing cavity). This reduces the coaxiality requirement of the shaft end of the large cavity, which is conducive to assembly and reduces the machining accuracy requirement. It is also suitable for occasions where the spindle warps due to high temperature and its own weight.

[0020] 4. Furthermore, the multiple sealing surfaces form a curved seal, which improves the sealing ability.

[0021] 5. Furthermore, by using inner and outer spiral sleeves with opposite rotation directions, a spiral labyrinth seal is formed. This is the first stage of the seal, which can push most of the material back into the vessel cavity, reducing the pressure of the subsequent dynamic and static ring seals and improving the overall sealing capability.

[0022] 6. Furthermore, the modular design of the dynamic and static rings facilitates daily maintenance and replacement.

[0023] 7. Furthermore, each component is characterized by high temperature resistance and wear resistance, which can prevent damage caused by thermal expansion due to high temperature operation of the equipment. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] Figure 1 This is a schematic diagram of the external structure of a preferred embodiment of the present invention;

[0026] Figure 2 This is a cross-sectional view of a preferred embodiment of the present invention;

[0027] Figure 3 This is a partial structural diagram of the floating seal assembly.

[0028] Figure 4 This is a schematic diagram of the three-dimensional structure of the assembled stationary ring;

[0029] Figure 5 This is a cross-sectional view of the assembled stationary ring;

[0030] Figure 6 This is a schematic diagram of the three-dimensional structure of the assembled dynamic ring;

[0031] Figure 7 This is a cross-sectional view of the assembled dynamic ring;

[0032] Figure 8 A schematic diagram showing the use of cylindrical saw teeth for the outer spiral sleeve;

[0033] Figure 9 This is a schematic diagram showing the inner spiral sleeve and the first sealing seat as an integral unit.

[0034] The attached figures are labeled as follows:

[0035] 1. Pressure cap; 2. Third sealing seat; 3. Second sealing seat; 4. First sealing seat; 5. Air nozzle; 6. Stationary ring anti-rotation pin; 7. Stationary ring; 8. Stationary ring radial limit ring; 9. Graphite gasket; 10. Rotary ring; 11. Spring seat; 12. Second cooling water outlet; 13. Spring seat fixing pin; 14. First cooling water outlet; 15. Inner spiral sleeve fixing screw; 16. Inner spiral sleeve; 17. Outer spiral sleeve; 18. First cooling water inlet; 19. Second cooling water inlet; 20. Spring; 21. Push ring; 22. Graphite packing; 23. Bushing; 24. Bushing fixing pin; 71. Semicircular stationary ring body; 72. Stationary ring clamp; 73. Stationary ring assembly positioning pin; 74. Stationary ring anti-rotation pin mounting hole; 101. Semicircular rotating ring body; 102. Rotary ring assembly positioning pin; 103. Slot; 2-1. Detailed Implementation

[0036] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present invention will become clearer and more apparent. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them.

[0037] like Figures 1 to 9 As shown, this embodiment discloses a floating mechanical seal device for high-temperature equipment, including a sealing seat assembly and a bushing 23 that is rotatably fitted with the sealing seat assembly. In this embodiment, the sealing seat assembly includes a first sealing seat 4, a second sealing seat 3, and a third sealing seat 2, which are assembled and sealed together by a bolted flange structure. Graphite sealing gaskets 9 are installed at the mating joints of the first and second sealing seats and the second and third sealing seats. The bushing is fixed to the rotating shaft by a bushing fixing pin 24 and rotates with the rotating shaft.

[0038] A sealing cavity is formed between the second sealing seat and the bushing. A spring seat 11, which is fixedly fitted to the bushing, is installed within the sealing cavity. In this embodiment, the spring seat is fixed to the bushing via a spring seat fixing pin 13. Floating sealing assemblies are fitted between the two sides of the spring seat and the corresponding sidewalls of the sealing cavity. Each floating sealing assembly includes a stationary ring 7, a stationary ring radial limiting ring 8, a moving ring 10, and a push ring 21, which are sequentially fitted onto the bushing. One side of the stationary ring is connected to the sealing seat assembly via multiple circumferentially arranged stationary ring anti-rotation pins 6 to achieve circumferential limiting between them. The stationary ring and the stationary ring radial limiting ring are nested together. Figure 4 As shown, the side of the stationary ring is provided with a stationary ring anti-rotation pin mounting hole 74. The stationary ring anti-rotation pin mounting hole is slightly larger than the stationary ring anti-rotation pin 6, so that the stationary ring 7 can play a certain up and down floating role with the rotating shaft. The stationary ring 7 is embedded in the retaining ring 8, so that the stationary ring 7 floats in the retaining ring 8 in the vertical direction. The embedding of the stationary ring 7 in the retaining ring 8 is beneficial to improving the structural strength of the stationary ring 7.

[0039] The other side of the stationary ring is tightly fitted with the moving ring, and the side of the moving ring away from the stationary ring is tightly fitted with the push ring. Multiple slots 104 are circumferentially formed on the outer circumferential surface of the moving ring. The spring seat is integrally provided with a claw 2-1 that engages with the slots, thus enabling the moving ring, spring seat, and bushing to rotate synchronously with the shaft. Multiple springs 20 are circumferentially fitted between the side of the push ring away from the moving ring and the corresponding sidewall of the spring seat. Spring mounting holes are formed on the spring seat. Under the action of the spring force, the push ring presses against the moving ring, and the end face of the stationary ring 7 abuts against the end face of the moving ring 10, thus enabling the moving ring 10 and spring seat 11 to rotate with the bushing 23. The stationary ring 7 is relatively fixed by the stationary ring anti-rotation pin 6. While the stationary ring 7 is floating, its end face is always pressed against the moving ring 10. The inner ring surface of the stationary ring 7 is in direct contact with the bushing 23. The gap between the moving ring 10 and the bushing 23 is slightly larger than the gap between the stationary ring and the bushing. Under the action of the elastic thrust, the following is achieved: Figure 3 The two sealing surfaces shown, namely the end face seal and the axial seal, effectively improve the sealing capability.

[0040] One end of the sealing seat assembly is equipped with a gland sealing assembly, which includes a graphite packing 22 and a gland 1. The graphite packing is sealed between the sealing seat assembly and the bushing. The gland presses the graphite packing and is fixedly assembled with the sealing seat assembly by the gland fixing screws. The sealing cavity is connected to a gas nozzle 5, through which pressurized gas is introduced. The gas pressure inside the sealing cavity is slightly higher than the gas pressure inside the vessel. On the one hand, the pressurized gas filling the sealing cavity helps to press the moving ring 10 against the stationary ring 7, and at the same time, a certain pressure tightly holds the stationary ring 7 against the bushing 23. On the other hand, the pressure inside the sealing cavity is greater than the pressure inside the vessel, which achieves the purpose of preventing material leakage inside the equipment and isolating outside air. The gas pressure inside the sealing cavity can be detected in real time. Once the pressure drops, on-site investigation can be carried out to determine whether the graphite packing 22 may need to be replaced or the gland fixing screws need to be tightened. This plays a role in timely detection and immediate plugging of leaks. The graphite packing 22 here not only cooperates with the sealing cavity to seal, but also prevents external dust from entering the sealing device.

[0041] Both the first and second sealing seats are equipped with water-cooling jackets. The water-cooling jacket of the first sealing seat is connected to a first cooling water inlet 18 and a first cooling water outlet 14. The water-cooling jacket of the second sealing seat is connected to a second cooling water inlet 19 and a second cooling water outlet 12. The cooling water enters from the bottom and exits from the top, cooling the entire sealing seat.

[0042] As a further improvement to the above technical solution, a vortex-type anti-leakage component is fitted at the end of the sealing seat assembly away from the gland sealing assembly. The vortex-type anti-leakage component includes an inner spiral sleeve 16 and an outer spiral sleeve 17 coaxially fitted together. The inner spiral sleeve is integrally connected to the sealing seat assembly, or fixedly connected to the sealing seat assembly via an inner spiral sleeve fixing screw 15. The inner and outer spiral sleeves have opposite rotation directions, and the outer spiral sleeve is fixed to the rotating shaft and rotates with the shaft. The inner spiral sleeve 16 and outer spiral sleeve 17 are made of low-expansion alloy steel, with a certain gap between them, ranging from 1-2 mm. The helical teeth of the inner and outer threads are arranged alternately with the gap. When the rotating shaft rotates, the fluid undergoes vortex friction between the spirals with opposite rotation directions, generating pressure to overcome leakage. The cooperation of the inner and outer spiral sleeves can isolate most of the material and push it back into the vessel.

[0043] In this embodiment, as Figure 4 and Figure 5 As shown, the stationary ring is composed of two semi-circular stationary ring bodies 71. The two semi-circular stationary ring bodies are assembled and positioned by stationary ring assembly positioning pins 73, and are joined together as a whole by stationary ring clamps 72. The stationary ring is made of graphite impregnation material, which is dense and airtight, has high hardness and wear resistance, and the end face and inner ring face are ground to improve the smoothness.

[0044] In this embodiment, the moving ring is composed of two semi-circular moving ring bodies 101 assembled together. The two semi-circular moving ring bodies are assembled and positioned by moving ring assembly positioning pins 103, and are joined together as a whole by moving ring clamps 102. The moving ring is made of metal, and the end sealing surface is sprayed with a wear-resistant coating, such as tungsten carbide or zirconium oxide, and then ground.

[0045] Furthermore, it is necessary to note that the stationary and rotating rings can be of integral structure rather than assembled type, which can improve the overall structural strength. Alternatively, one can be assembled and the other integral. The stationary and rotating rings can be made of the same material, such as impregnated graphite, silicon carbide, Hastelloy, etc., or two materials can be combined. What they all share is that the sealing surfaces need to be ground to improve surface finish. The helical teeth of the inner spiral sleeve 16 and the outer spiral sleeve 17 can be rectangular, trapezoidal, triangular, or arc-shaped, or two can be combined. In addition, the serrations on the outer circumference of the outer spiral sleeve can be non-spiral arranged, directly using spaced cylindrical serrations, specifically as follows... Figure 8 As shown, the inner spiral sleeve can be removed, and the inner spiral sleeve and the first sealing seat can be made as a single unit, as shown in the following figure. Figure 9 As shown.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A floating mechanical seal device for high-temperature equipment capable of adapting to shaft end warping changes, characterized in that: The device includes a sealing seat assembly and a bushing that is rotatably fitted with the sealing seat assembly. A sealing cavity is formed between the sealing seat assembly and the bushing. An air nozzle is connected to the sealing cavity. A spring seat that is fixedly fitted with the bushing is installed inside the sealing cavity. Floating sealing components are fitted between the two sides of the spring seat and the corresponding sidewalls of the sealing cavity. The floating seal assembly includes a stationary ring, a stationary ring radial limiting ring, a rotating ring, and a push ring, which are sequentially fitted onto the bushing. One side of the stationary ring is connected to the seal seat assembly via multiple circumferentially arranged anti-rotation pins to achieve circumferential limiting between them. The side of the stationary ring has a mounting hole for the anti-rotation pin, which is slightly larger than the anti-rotation pin. The other side of the stationary ring is tightly fitted with the rotating ring, and the stationary ring and the stationary ring radial limiting ring are nested together. The side of the rotating ring away from the stationary ring is tightly fitted with the push ring. The outer circumferential surface of the rotating ring has multiple slots, and the spring seat is integrally provided with a claw that engages with the slots. The side of the push ring away from the rotating ring is circumferentially fitted between the push ring and the corresponding sidewall of the spring seat, and the spring seat has spring mounting holes. The sealing cavity is supplied with pressurized gas through the air nozzle. The pressure generated by the pressurized gas tightly holds the stationary ring against the bushing. Under the action of the spring and the air pressure in the sealing cavity, the stationary ring can float up and down with the deformed bushing, keeping the end face sealing surface of the stationary ring always pressed against the moving ring. One end of the sealing seat assembly is equipped with a gland sealing assembly; the gland sealing assembly includes a graphite packing and a gland, the graphite packing is sealed between the sealing seat assembly and the bushing, and the gland presses the graphite packing and is fixedly assembled with the sealing seat assembly by the gland fixing screws; The sealing seat assembly is equipped with a vortex-type anti-leakage component at one end away from the gland sealing assembly; the vortex-type anti-leakage component includes an inner spiral sleeve and an outer spiral sleeve that are coaxially sleeved together, the inner spiral sleeve being integrally connected to the sealing seat assembly, or being fixedly connected to the sealing seat assembly by an inner spiral sleeve fixing screw, and the inner spiral sleeve and the outer spiral sleeve having opposite rotation directions.

2. The floating mechanical seal device according to claim 1, characterized in that: The stationary ring is composed of two semi-circular stationary ring bodies assembled together. The two semi-circular stationary ring bodies are assembled and positioned by stationary ring assembly positioning pins, and are then joined together as a whole by stationary ring clamps.

3. The floating mechanical seal device according to claim 2, characterized in that: The moving ring is composed of two semi-circular moving ring bodies assembled together. The two semi-circular moving ring bodies are assembled and positioned by moving ring assembly positioning pins, and are then joined together as a whole by moving ring clamps.

4. The floating mechanical seal device according to any one of claims 1-3, characterized in that: The sealing seat assembly includes a first sealing seat, a second sealing seat, and a third sealing seat, which are assembled by bolted flange platform structure. Graphite sealing gaskets are installed at the mating assembly points of the first and second sealing seats and the second and third sealing seats.

5. The floating mechanical seal device according to claim 4, characterized in that: Both the first sealing seat and the second sealing seat are equipped with water-cooled jackets. The water-cooled jacket of the first sealing seat is connected to a first cooling water inlet and a first cooling water outlet. The water-cooled jacket of the second sealing seat is connected to a second cooling water inlet and a second cooling water outlet.

Images