Double-end self-cooling mechanical seal

Abstract

This invention discloses a double-end-face self-cooling mechanical seal, relating to the field of centrifugal pumps. The device includes a cooling sleeve, a transmission fixing component, a lower static seal seat, an upper static seal seat, a lower static seal ring, an upper static seal ring, a lower static seal gland, an upper static seal gland, and two sets of clamping moving rings. The cooling sleeve is inserted into the centrifugal pump impeller shaft and is located at the end of the pump head. The transmission fixing component is located inside the cooling sleeve. The lower static seal seat is installed on the side of the cooling sleeve away from the pump head, and the upper static seal seat is installed on the side of the cooling sleeve closer to the pump head. The two sets of clamping moving rings are slidably connected to both sides of the transmission fixing component. Two sets of elastic elements are provided between the two sets of clamping moving rings and the transmission fixing component. This device uses double independent end-face seals to form a double barrier, preventing direct leakage of the medium to the environment; the integrated cooling sleeve allows the sealing components to be fully immersed and cooled, avoiding dry friction burning of the sealing surfaces; and the double-sided independent elastic pre-tightening achieves independent compensation for wear on the upper and lower sealing surfaces.

Description

Technical Field

[0001] This invention relates to the field of centrifugal pumps, and particularly to a double-end-face self-cooling mechanical seal. Background Technology

[0002] Single-stage, single-suction centrifugal pumps are the most widely used pump type in industrial fluid transportation. Among them, polypropylene (non-metallic) corrosion-resistant centrifugal pumps, with their excellent acid and alkali corrosion resistance, low manufacturing cost, and mature manufacturing process, have become the preferred equipment for conveying corrosive liquids in industries such as chemical, pharmaceutical, electroplating, and environmental water treatment. Currently, the vast majority of single-stage, single-suction polypropylene (non-metallic) centrifugal pumps worldwide use the WB2 type single-end mechanical seal as the standard shaft seal configuration. This seal structure has been verified through years of industrial application and has significant advantages such as good corrosion resistance, compact structure, high degree of component standardization, low initial procurement cost, and simple daily maintenance and operation. Therefore, it is widely used in the industry and occupies more than 90% of the market share.

[0003] Existing single-stage, single-suction polypropylene (non-metallic) centrifugal pumps with single-end-face seals suffer from wear on the single sealing surface due to the limited number of sealing barriers. This wear inevitably leads to seal failure, allowing corrosive media to leak directly into the environment, posing serious environmental and safety hazards. Furthermore, overheating and burnout of the seal can cause deformation or damage to other core components such as the pump body, impeller, and mechanical seal cover, resulting in repair costs approaching the total price of all pump parts except the motor. Secondly, existing single-end-face seals rely solely on the pump's internal cooling system, making it difficult to dissipate heat generated by friction on the sealing surface quickly. Prolonged operation can lead to vaporization of the liquid film on the sealing surface and dry friction burnout, typically reducing the seal's lifespan to less than six months. To address these issues, this invention provides a double-end-face self-cooling mechanical seal. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a double-end-face self-cooling mechanical seal. This solves the problem that in existing single-stage, single-suction polypropylene (non-metallic) centrifugal pumps, the sealing surface inevitably wears during long-term high-speed rotation. Once the seal fails, corrosive media inside the pump will leak directly into the external environment, posing serious environmental and safety hazards. Furthermore, when the seal overheats and burns out, the leaked corrosive media will cause deformation or burnout of peripheral core components such as the pump body, impeller, and mechanical seal cover. The cost of a single repair is close to the total price of all parts of the entire centrifugal pump except for the motor. In addition, existing single-end-face seals rely solely on the medium transported inside the pump for cooling, and the heat generated by friction on the sealing surface is difficult to dissipate quickly. Long-term operation can easily lead to vaporization of the liquid film on the sealing surface and dry friction burnout, and the seal's service life is usually less than six months.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a double-end-face self-cooling mechanical seal, comprising a cooling sleeve, a transmission fixing component, a lower static seal seat, an upper static seal seat, a lower static seal ring, an upper static seal ring, a lower static seal gland, an upper static seal gland, and two sets of clamping moving rings. The cooling sleeve is inserted into the impeller shaft of a centrifugal pump and is located at the end of the pump head. The cooling sleeve has a hollow cylindrical structure. The transmission fixing component is located inside the cooling sleeve and is used to fix and connect to the impeller shaft and rotate synchronously with the impeller shaft. The lower static seal seat is installed on the cooling sleeve away from the pump head. On one side, it is used to separate the coolant inside the cooling sleeve from the outside. The upper static seal is installed on the side of the cooling sleeve near the pump head. It is used to isolate the cooling sleeve and the pump head to prevent the liquid inside the pump head from flowing into the cooling sleeve along the impeller shaft. The two sets of clamping moving rings are slidably connected to both sides of the transmission fixing component. Two sets of elastic elements are provided between the two sets of clamping moving rings and the transmission fixing component. The transmission fixing component is used to fix the two sets of clamping moving rings to the impeller shaft. Under the action of the two sets of elastic elements, the two sets of clamping moving rings respectively press the lower static seal ring and the upper static seal ring onto the lower static seal and the upper static seal.

[0006] Preferably, the transmission fixing component is a single clamp, which is disposed inside the cooling sleeve and is fixedly installed on the impeller shaft.

[0007] Preferably, the transmission fixing component consists of two sets of clamps, both sets of clamps are disposed inside the cooling sleeve, and both sets of clamps are fixedly installed on the impeller shaft.

[0008] Preferably, a telescopic tube section is fixedly connected to the inner side of the pressing ring, and the other end of the telescopic tube section abuts against the transmission fixing component. The two sets of elastic elements include one or more springs evenly distributed along the circumferential direction of the impeller shaft. One end of the spring is fixedly connected to the side end of the transmission fixing component, and the other end of the spring is fixedly connected to the pressing ring.

[0009] Preferably, a lower static sealing ring is fixedly installed inside the lower static sealing seat, and an upper static sealing ring is fixedly installed inside the upper static sealing seat. Both the upper and lower static sealing rings are used to seal the impeller shaft. A lower static sealing cover is installed on the lower static sealing seat, and the lower static sealing cover is used to install the lower static sealing ring on the lower static sealing seat. An upper static sealing cover is installed on the upper static sealing seat, and the upper static sealing cover is used to install the upper static sealing ring on the upper static sealing seat.

[0010] Preferably, the cooling sleeve has an input end for inputting cooling water and an output end for outputting cooling water. Connecting flange seats are fixedly connected to both sides of the cooling sleeve, and the lower static seal seat and the upper static seal seat are both flange-connected to the connecting flange seats.

[0011] The technical effects and advantages of this invention are as follows: This dual-end-face self-cooling mechanical seal uses two independent end-face sealing systems to form a double sealing barrier. When the seal near the medium side wears and leaks, the medium will be sealed inside the cooling water jacket and will not leak directly to the external environment. When the seal away from the medium side wears and leaks, water will leak out instead of corrosive media, which fundamentally eliminates the environmental and safety hazards caused by media leakage. The dual-end self-cooling mechanical seal integrates a sealing housing as a cooling chamber, with all moving sealing components directly immersed in the coolant. The heat generated by friction on the sealing surface can be continuously carried away by the flowing coolant, preventing vaporization of the liquid film on the sealing surface and dry friction burnout, thus eliminating the risk of damage to surrounding components caused by overheating of the seal. This double-end self-cooling mechanical seal adopts a double-sided independent elastic pre-tightening structure, and the pre-tightening forces of the upper and lower sealing surfaces do not interfere with each other; the wear of the two sealing surfaces can be automatically compensated independently by their respective elastic elements, ensuring that the sealing surfaces are always in a stable fit and extending the overall service life of the seal.

[0012] This dual-end self-cooling mechanical seal adopts a modular integrated design, with each component connected by flanges, making replacement simple and reducing equipment maintenance and upgrade costs. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the overall side structure of the present invention; Figure 2 This is a schematic diagram of the internal cross-sectional structure of the present invention; Figure 3 This is a schematic diagram of the internal exploded structure of the present invention; Figure 4 This is a schematic diagram showing the detailed structure of the explosion of the present invention; Figure 5 This is a schematic diagram showing the detailed structure of the clamp of the present invention; Figure 6 This is a detailed structural diagram of the second embodiment of the clamp of the present invention.

[0015] In the diagram: 1. Cooling sleeve; 11. Input end; 12. Output end; 13. Connecting flange seat; 2. Clamp; 21. Elastic element; 3. Lower static seal seat; 31. Lower static seal gland; 4. Upper static seal seat; 41. Upper static seal gland; 5. Pressing ring; 51. Telescopic pipe section; 6. Upper static seal ring; 7. Lower static seal ring. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0018] This invention discloses a double-end-face self-cooling mechanical seal, according to the appendix. Figures 1 to 4 As shown, the system includes a cooling sleeve 1, a transmission fixing component, a lower static seal seat 3, an upper static seal seat 4, a lower static seal ring 7, an upper static seal ring 6, a lower static seal gland 31, an upper static seal gland 41, and two sets of clamping moving rings 5. The cooling sleeve 1 is inserted into the centrifugal pump impeller shaft and is located at the end of the pump head. The cooling sleeve 1 has a hollow cylindrical structure. The transmission fixing component is located inside the cooling sleeve and is used to fix and connect to the impeller shaft and rotate synchronously with the impeller shaft. The lower static seal seat 3 is installed on the side of the cooling sleeve 1 away from the pump head and is used to cool the contents of the cooling sleeve 1. The coolant is separated from the outside environment. The upper static seal 4 is installed on the side of the cooling sleeve 1 near the pump head. It is used to isolate the cooling sleeve 1 and the pump head to prevent the liquid in the pump head from flowing into the cooling sleeve 1 along the impeller shaft. Two sets of clamping moving rings 5 ​​are slidably connected to both sides of the transmission fixing component. Two sets of elastic elements are provided between the two sets of clamping moving rings 5 ​​and the transmission fixing component. The transmission fixing component is used to fix the two sets of clamping moving rings 5 ​​to the impeller shaft. Under the action of the two sets of elastic elements, the two sets of clamping moving rings 5 ​​respectively press the lower static seal 7 and the upper static seal 6 onto the lower static seal 3 and the upper static seal 4.

[0019] According to the appendix Figures 3 to 5 As shown, further, the transmission fixing component is a single clamp 2, which is set inside the cooling sleeve 1 and fixedly installed on the impeller shaft.

[0020] According to the appendix Figures 3 to 5 As shown, further, the transmission fixing components are two sets of clamps 2, both sets of clamps 2 are set inside the cooling sleeve 1, and the two sets of clamps 2 are fixedly installed on the impeller shaft.

[0021] In this embodiment, the two sets of clamps 2 form a complete moving ring with the pressing moving ring 5 on one side. If one set of pressing moving ring 5 is damaged, it can be repaired by replacing the set of moving rings, without having to replace the moving ring on the other side.

[0022] According to the appendix Figures 1 to 4 As shown, a telescopic tube section 51 is fixedly connected to the inner side of the pressing ring 5. The other end of the telescopic tube section 51 abuts against the transmission fixing member. The two sets of elastic members include one or more springs 21 evenly distributed along the circumferential direction of the impeller shaft. One end of the spring 21 is fixedly connected to the side end of the transmission fixing member, and the other end of the spring 21 is fixedly connected to the pressing ring 5.

[0023] In this embodiment, the cooling sleeve 1 is a hollow cylindrical structure with an input end 11 and an output end 12 on its side wall. All sealing moving parts are located inside the cooling sleeve 1, which solves the problem that existing seals rely solely on the conveying medium for cooling, and the heat generated by friction on the sealing surface cannot be dissipated in time, leading to overheating and burnout. In addition, a set of elastic elements is provided on both sides of the transmission fixing component, and the two sets of elastic elements act on the two sets of pressing moving rings 5 ​​respectively, which solves the problem that the pre-tightening forces of the upper and lower sealing surfaces of the existing double-end face seals interfere with each other, and the overall pre-tightening force becomes unbalanced after wear on one side, thus realizing independent automatic compensation for wear on the upper and lower sealing surfaces.

[0024] According to the appendix Figures 1 to 4 As shown, it is particularly important to emphasize that a lower static sealing ring 7 is fixedly installed inside the lower static sealing seat 3, and an upper static sealing ring 6 is fixedly installed inside the upper static sealing seat 4. Both the upper static sealing ring 6 and the lower static sealing ring 7 are used to seal the impeller shaft. A lower static sealing cover 31 is installed on the lower static sealing seat 3, and the lower static sealing cover 31 is used to install the lower static sealing ring 7 on the lower static sealing seat 3. An upper static sealing cover 41 is installed on the upper static sealing seat 4, and the upper static sealing cover 41 is used to install the upper static sealing ring 6 on the upper static sealing seat 4.

[0025] In this embodiment, an upper static sealing seat 4 and a lower static sealing seat 3 are respectively provided at both ends of the cooling sleeve 1. An upper static sealing ring 6 is installed in the upper static sealing seat 4, and a lower static sealing ring 7 is installed in the lower static sealing seat 3. The two sets of pressing moving rings 5 ​​are respectively attached to the end faces of the upper static sealing ring 6 and the lower static sealing ring 7 to form two independent sealing systems, which solves the problem that the existing single-end face seal only sets one sealing barrier, and the medium directly leaks to the external environment after failure.

[0026] According to the appendix Figures 1 to 4 As shown, it is important to emphasize that the cooling sleeve 1 has an input end 11 for inputting cooling water and an output end 12 for outputting cooling water. The cooling sleeve 1 is fixedly connected to both sides of the connecting flange seat 13, and the lower static seal seat 3 and the upper static seal seat 4 are both flanged to the connecting flange seat 13.

[0027] In this embodiment, connecting flange seats 13 are provided on both sides of the cooling sleeve 1. The upper static sealing seat 4 and the lower static sealing seat 3 are both connected to the connecting flange seat 13 flange. The upper static sealing ring 6 is fixed to the upper static sealing seat 4 by the upper static sealing cover 41, and the lower static sealing ring 7 is fixed to the lower static sealing seat 3 by the lower static sealing cover 31. This solves the problem of the existing double-end face sealing structure being complex and the installation and replacement process being cumbersome, and can be directly adapted to the installation interface of existing rotating machinery.

[0028] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A double-end-face self-cooling mechanical seal, characterized in that, include: Cooling sleeve (1), the cooling sleeve (1) is inserted into the centrifugal pump impeller shaft, the cooling sleeve (1) is set at the end of the pump head, and the cooling sleeve (1) is a hollow cylindrical structure; A transmission fixing component is disposed inside the cooling sleeve, and the transmission fixing component is used to be fixedly connected to the impeller shaft and rotate synchronously with the impeller shaft. The lower static seal (3) is installed on the side of the cooling sleeve (1) away from the pump head, and is used to separate the coolant in the cooling sleeve (1) from the outside. Upper static seal (4) is installed on the side of the cooling sleeve (1) near the pump head. It is used to isolate the cooling sleeve (1) and the pump head to prevent liquid in the pump head from flowing into the cooling sleeve (1) along the impeller shaft. Two sets of clamping moving rings (5) are slidably connected to both sides of the transmission fixing component. Two sets of elastic elements are provided between the two sets of clamping moving rings (5) and the transmission fixing component. The transmission fixing component is used to fix the two sets of clamping moving rings (5) to the impeller shaft. Under the action of the two sets of elastic elements, the two sets of clamping moving rings (5) respectively press the lower static sealing ring (7) and the upper static sealing ring (6) onto the lower static sealing seat (3) and the upper static sealing seat (4).

2. The double-end-face self-cooling mechanical seal according to claim 1, characterized in that, The transmission fixing component is a single clamp (2), which is set inside the cooling sleeve (1) and is fixedly installed on the impeller shaft.

3. The double-end-face self-cooling mechanical seal according to claim 1, characterized in that, The transmission fixing component consists of two sets of clamps (2), both sets of clamps (2) are set inside the cooling sleeve (1), and the two sets of clamps (2) are fixedly installed on the impeller shaft.

4. The double-end-face self-cooling mechanical seal according to claim 1, characterized in that, The inner side of the pressing ring (5) is fixedly connected to a telescopic pipe section (51), and the other end of the telescopic pipe section (51) abuts against the transmission fixing component.

5. The double-end-face self-cooling mechanical seal according to claim 4, characterized in that, The two sets of elastic elements include one or more springs (21) evenly distributed along the circumferential direction of the impeller shaft. One end of the spring (21) is fixedly connected to the side end of the transmission fixing member, and the other end of the spring (21) is fixedly connected to the pressing moving ring (5).

6. The double-end-face self-cooling mechanical seal according to claim 1, characterized in that, The lower static sealing seat (3) is fixedly connected to a lower static sealing ring (7), and the upper static sealing seat (4) is fixedly connected to an upper static sealing ring (6). Both the upper static sealing ring (6) and the lower static sealing ring (7) are used to seal the impeller shaft.

7. The double-end-face self-cooling mechanical seal according to claim 6, characterized in that, The lower static sealing seat (3) is equipped with a lower static sealing cover (31), which is used to install the lower static sealing ring (7) on the lower static sealing seat (3). The upper static sealing seat (4) is equipped with an upper static sealing cover (41), which is used to install the upper static sealing ring (6) on the upper static sealing seat (4).

8. The double-end-face self-cooling mechanical seal according to claim 1, characterized in that, The cooling sleeve (1) has an input end (11) for inputting cooling water, and an output end (12) for outputting cooling water.

9. The double-end-face self-cooling mechanical seal according to claim 1, characterized in that, The cooling sleeve (1) is fixedly connected to the connecting flange seat (13) on both sides, and the lower static seal seat (3) and the upper static seal seat (4) are both flange connected to the connecting flange seat (13).

Images