Low-deflection mechanical seal for horizontal kettle

Abstract

The low-deflection mechanical seal for the horizontal kettle comprises a connecting flange, a corrugated pipe, a sealing box and a bearing seat which are sequentially arranged from a medium end to an atmosphere end, the corrugated pipe is connected between the sealing box and the connecting flange in a pressing mode, isolation gas is filled in the corrugated pipe, flammable and explosive gas can be prevented from flowing into the sealing box, and the sealing box is prevented from being damaged. The cleanness of the whole sealing device is ensured. A labyrinth structure is designed on the side, close to a medium, of the buffering cavity, and solid impurities generated by equipment are prevented from flowing into the buffering cavity and the mechanical seal. The static mechanical seal design is adopted for the medium end, the medium end spring is connected into the sealing box, and it can be guaranteed that the mechanical seal can still be used under the high deflection condition to the maximum extent. According to the mechanical seal for the horizontal kettle, the bearing is connected with the shaft sleeve, and axial force and radial force generated in the working process are concentrated on the bearing and then buffered by the corrugated pipe. The mechanical sealing device is high in sealing capacity, long in service life and suitable for occasions with deviation of mechanical sealing.

Description

Technical Field

[0001] The utility model relates to a mechanical seal, in particular to a mechanical seal for a horizontal kettle with low deflection. Background Art

[0002] Mechanical seals are used in industrial production to effectively seal grease, fuel, and gas in equipment fluids, ensuring the safety of the equipment during operation. For large horizontal machines, such as dryers, kneaders, screw conveyors, etc., double-end mechanical seals are usually used to seal both the medium side and the atmosphere side. However, due to the operating temperature and its own weight, the main shaft of the mechanical seal will extend by approximately 8mm after operating at high temperatures, causing the main shaft to deviate axially. The components that make up the mechanical seal device will also deviate radially, resulting in a shortened lifespan of the mechanical seal. Radial-axial runout has become a bottleneck problem in the development of many large horizontal machines, so there is a need to improve the structure of existing mechanical seals. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a mechanical seal for a horizontal kettle with low deflection, comprising a main shaft, a sleeve arranged on the outside of the main shaft, and a connecting flange, a bellows, a sealing box and a bearing seat provided on the outside of the sleeve from the medium end to the atmosphere end in sequence; a double-end sealing assembly is installed in the sealing box, and the bearing seat is connected to the sleeve through a bearing arranged inside; the bellows is crimped between the sealing box and the connecting flange, and the sealing box and the connecting flange are located at both ends of the bellows, and enclose a closed buffer chamber inside the bellows with the sleeve, and the buffer chamber is filled with an inert gas that isolates the sealing box.

[0004] Furthermore, the bellows is a metal bellows.

[0005] Furthermore, a first sealing member is provided at one end of the bellows close to the connecting flange, and the first sealing member is clamped between the shaft sleeve and the connecting flange.

[0006] Furthermore, a labyrinth structure is provided between the connecting flange and the sleeve, including a labyrinth inner ring provided on the outside of the sleeve and a labyrinth outer ring provided on the connecting flange, the ends of the labyrinth inner ring and the labyrinth outer ring are respectively formed with grooves, and the two grooves are interlaced.

[0007] Furthermore, a pin hole is provided on one side of the labyrinth inner ring close to the shaft sleeve, and a pin shaft is provided on the outer surface of the shaft sleeve to be inserted into the pin hole.

[0008] Furthermore, the double-end sealing assembly includes an atmospheric side sealing assembly and a medium side sealing assembly, the atmospheric side sealing assembly includes an atmospheric side spring seat fixedly connected to the shaft sleeve, and the atmospheric side dynamic ring is connected to the atmospheric side spring seat through the atmospheric side spring; the sealing box is connected to an atmospheric side static ring on the side close to the bearing seat, and the atmospheric side static ring is in contact with the end face of the atmospheric side dynamic ring to form a set of sealing end faces on the atmospheric side.

[0009] Furthermore, the medium side sealing assembly includes a medium side spring seat fixed on the inner side of the sealing box, and the medium side static ring is connected to the medium side spring seat through the medium side spring; a medium side dynamic ring is installed on the medium side of the sleeve, and the medium side dynamic ring contacts the end face of the medium side static ring to form a set of sealing end faces on the medium side.

[0010] Furthermore, the contact end surfaces of the medium-side dynamic ring and the medium-side static ring are matched with each other and have the same size.

[0011] Furthermore, a transmission ring is provided on the atmospheric side of the main shaft, a transmission groove is provided on the atmospheric side end of the sleeve, one end of the transmission ring is pressed against the outside of the main shaft, and the other end is pressed against the outside of the transmission groove.

[0012] Furthermore, the transmission ring is a half-split structure, formed by two half rings embracing each other.

[0013] The utility model provides a mechanical seal for a horizontal kettle, including a connecting flange, a bellows, a sealing box and a bearing seat arranged in sequence from the medium end to the atmosphere end. The bellows is crimped between the sealing box and the connecting flange, and the bellows is filled with an isolation gas, which can prevent flammable and explosive gases from flowing into the sealing box and ensure the cleanliness of the entire sealing device. The buffer chamber is designed with a labyrinth structure on the side close to the medium to prevent solid impurities generated by the equipment from flowing into the buffer chamber and the mechanical seal. The medium end of the utility model adopts a static mechanical seal design, and the medium end spring is connected in the sealing box, which can maximize the guarantee that the mechanical seal can still be used in high deflection conditions.

[0014] The horizontal kettle mechanical seal provided by this utility model relies on a bearing connected to a sleeve. The radial forces generated during operation are concentrated on the bearing and then buffered by the bellows, thereby reducing the axial and radial deflection of the mechanical seal. The utility model has a strong sealing ability and a long service life, and is suitable for applications where the mechanical seal is subject to deflection. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic structural diagram of a mechanical seal for a horizontal kettle with low deflection in the utility model;

[0016] Figure 2 It is an enlarged schematic diagram of the maze structure;

[0017] Figure 3It is an enlarged schematic diagram of the double-end sealing component of the utility model.

[0018] Figure numerals: main shaft 1, sleeve 2, connecting flange 3, bellows 4, sealing box 5, bearing seat 6, bearing 7, buffer chamber 8, first seal 9, labyrinth outer ring 10, labyrinth inner ring 11, pin 12, fixing ring 13, atmospheric side spring seat 14, atmospheric side static ring 15, atmospheric side spring 16, atmospheric side dynamic ring 17, atmospheric side thrust ring 18, medium side spring seat 19, medium side static ring 20, medium side spring 21, medium side dynamic ring 22, medium side thrust ring 23, transition surface 24, groove 25, retaining spring 26, second seal 27, transmission ring 28. DETAILED DESCRIPTION

[0019] like Figure 1 The mechanical seal for a low-deflection horizontal kettle shown in the figure comprises a main shaft 1, a sleeve 2 sleeved on the outside of the main shaft 1, and a connecting flange 3, a bellows 4, a sealing box 5, and a bearing seat 6 arranged on the outside of the sleeve 2 from the medium end to the atmospheric end. A double-end seal assembly is installed within the sealing box 5, comprising two pairs of sealing end faces consisting of a dynamic ring and a static ring. The connecting flange 3 is connected to the equipment on the medium side, and the bearing seat 6 is connected to the sleeve 2 via an internal bearing 7. The bellows 4 is crimped between the sealing box 5 and the connecting flange 3. The connecting flange 3, bellows 4, sealing box 5, and bearing seat 6 form a complete housing structure wrapped around the main shaft 1, maintaining the compactness of the entire sealing device.

[0020] The sealing device provided by the present invention is intended to address the axial deviation of the main shaft 1 caused by thermal expansion and contraction in the prior art. A bellows 4 is provided between the sealing box 5 and the connecting flange 3. When the sealing device produces axial deviation, the bellows 4 can provide a certain elastic support, reducing the deviation of the sealing device. The bellows 4 is sleeved on the shaft sleeve 2. The sealing box 5 and the connecting flange 3 are located at both ends of the bellows 4. Together with the shaft sleeve 2, they form a sealed buffer chamber 8 inside the bellows 4. Inert gas is filled into the buffer chamber 8 to isolate the gas generated by the equipment, prevent flammable and explosive gases from flowing into the sealing box 5, and ensure the cleanliness of the entire sealing device. The bellows 4 is preferably made of metal, which can withstand large axial loads with minimal deformation, reducing the axial deviation of the mechanical seal. Furthermore, a first sealing member 9 is provided at one end of the bellows 4 near the connecting flange 3. The first sealing member 9 is a special sealing ring made of rubber and plastic material, which is clamped between the shaft sleeve 2 and the connecting flange 3 to seal the end of the bellows 4 and prevent gas leakage in the buffer chamber 8.

[0021] Furthermore, if Figure 2As shown, a labyrinth structure is provided between the connecting flange 3 and the sleeve 2. The labyrinth structure includes an inner labyrinth ring 11 disposed on the outside of the sleeve 2 and an outer labyrinth ring 10 disposed on the connecting flange 3. The ends of the inner labyrinth ring 11 and the outer labyrinth ring 10 are each formed with grooves, which are interlaced to form a labyrinth structure. The labyrinth structure can prevent solid debris generated on the medium side from flowing into the buffer chamber 8 within the device.

[0022] Specifically, a pin hole is provided on the side of the labyrinth inner ring 11 close to the sleeve 2, and a pin shaft 12 is provided on the outer surface of the sleeve 2 to be inserted into the pin hole. The pin shaft 12 cooperates with the pin hole to fix the position of the labyrinth inner ring 11. Furthermore, a fixing ring 13 is provided on the end of the labyrinth inner ring 11 close to the medium side. One end of the fixing ring 13 is crimped onto the surface of the labyrinth inner ring 11, and the other end is fixedly connected to the sleeve 2 via screws, thereby limiting the position of the labyrinth inner ring 11.

[0023] The double-end sealing assembly of this embodiment includes Figure 3 The atmospheric-side sealing assembly and the medium-side sealing assembly shown in the figure include an atmospheric-side spring seat 14 fixedly connected to the shaft sleeve 2, and an atmospheric-side dynamic ring 17 connected to the atmospheric-side spring seat 14 via an atmospheric-side spring 16. An atmospheric-side static ring 15 is connected to the side of the sealing box 5 near the bearing seat 6. The atmospheric-side static ring 15 contacts the end face of the atmospheric-side dynamic ring 17, forming a set of sealing end faces on the atmospheric side. The atmospheric-side spring 16 can dynamically adjust the position of the atmospheric-side dynamic ring 17 during operation, so that the atmospheric-side static ring 15 and the end face of the atmospheric-side dynamic ring 17 maintain contact. Furthermore, an atmospheric-side push ring 18 is installed between the atmospheric-side dynamic ring 17 and the atmospheric-side spring 16, and the atmospheric-side push ring 18 pushes the atmospheric-side dynamic ring 17.

[0024] The media-side seal assembly includes a media-side spring seat 19 fixed to the inside of the sealing box 5. A media-side stationary ring 20 is connected to the media-side spring seat 19 via a media-side spring 21. A media-side dynamic ring 22 is mounted on the media side of the sleeve 2. This dynamic ring 22 contacts the end face of the media-side stationary ring 20, forming a set of sealing end faces on the media side. The media-side seal assembly employs a stationary design, with the media-side stationary ring 20 connected to the media-side spring 21. When the seal deflects, the bellows 4 provides some cushioning, maintaining a relatively stable position between the dynamic ring 22 and the bellows 4, thereby minimizing deflection. Similarly, a media-side thrust ring 23 is mounted between the media-side stationary ring 20 and the media-side spring 21. The media-side spring 21 applies thrust to the media-side stationary ring 20 via the thrust ring 23.

[0025] Furthermore, the sleeve 2 is a cup-shaped structure that is narrow at the top and wide at the bottom. An inclined transition surface 24 is provided between the upper and lower portions of the sleeve 2. The inner side of the end of the bellows 4 that connects to the sealing box 5 is crimped onto the transition surface 24 and the outer side of the medium-side dynamic ring 22. The inclined transition surface 24 stabilizes the installation position of the bellows 4. Furthermore, an axially extending slot 25 is provided on the transition surface 24. One end of the medium-end dynamic ring extends into the slot 25, stabilizing the installation position of the medium-end dynamic ring.

[0026] Furthermore, the contact end faces of the medium-side dynamic ring 22 and the medium-side static ring 20 match each other and are set to the same size. There is no sealing dead angle when in contact, and the material will not penetrate from the medium sealing component to cause corrosion and wear of the sealing end face. At the same time, harmful bacteria are prevented from entering the sealing end face, meeting the high requirements of the pharmaceutical, food and other industries.

[0027] The sealing device provided in this embodiment is connected to the main shaft 1 via a bearing 7. The bearing 7 is connected to the inner wall of the bearing seat 6 via a retaining ring 26. The radial and axial forces generated by the mechanical seal are borne by the bearing 7, while any axial and radial deflections are absorbed by the bellows 4, thereby ensuring the sealing capability of the sealing device. Furthermore, a second seal 27 is installed between the bearing 7 frame and the shaft sleeve 2 to prevent leakage of media from the sealing box 5 into the bearing 7 frame. In this embodiment, the second seal 27 is a skeleton seal.

[0028] Furthermore, a transmission ring 28 is provided on the atmospheric side of the main shaft 1. A transmission groove is provided on the atmospheric-side end of the sleeve 2. One end of the transmission ring 28 is crimped onto the outside of the main shaft 1, while the other end is crimped onto the outside of the transmission groove. The transmission ring 28 maintains the synchronous rotation of the sleeve 2 and the main shaft 1. The transmission ring 28 is further configured as a semi-split structure, consisting of two half-rings embracing each other. This arrangement facilitates installation of the transmission ring 28 and increases the securing torque of the transmission ring 28 on the sleeve 2 without damaging the main shaft 1.

[0029] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations on the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A mechanical seal for a horizontal kettle with low deflection, characterized by: The invention comprises a main shaft (1), a shaft sleeve (2) sleeved on the outside of the main shaft (1), a connecting flange (3), a bellows (4), a sealing box (5) and a bearing seat (6) arranged on the outside of the shaft sleeve (2) from the medium end to the atmosphere end; a double-end sealing assembly is installed in the sealing box (5), and the bearing seat (6) is connected to the shaft sleeve (2) through a bearing (7) arranged inside; the bellows (4) is crimped between the sealing box (5) and the connecting flange (3), and the sealing box (5) and the connecting flange (3) are located at both ends of the bellows (4) and enclose a closed buffer chamber (8) inside the bellows (4) together with the shaft sleeve (2); the buffer chamber (8) is filled with an inert gas that isolates the sealing box (5).

2. A low deflection horizontal kettle mechanical seal according to claim 1, characterized in that: The bellows (4) is a metal bellows.

3. The low-deflection horizontal kettle mechanical seal according to claim 1, characterized in that: A first sealing member (9) is provided at one end of the bellows (4) close to the connecting flange (3), and the first sealing member (9) is clamped between the shaft sleeve (2) and the connecting flange (3).

4. The low-deflection horizontal kettle mechanical seal according to claim 1, characterized in that: A labyrinth structure is provided between the connecting flange (3) and the shaft sleeve (2), comprising a labyrinth inner ring (11) provided on the outside of the shaft sleeve (2) and a labyrinth outer ring (10) provided on the connecting flange (3), wherein the ends of the labyrinth inner ring (11) and the labyrinth outer ring (10) are respectively formed with grooves, and the two grooves are interlaced.

5. A low-deflection horizontal kettle mechanical seal according to claim 4, characterized in that: A pin hole is provided on one side of the labyrinth inner ring (11) close to the shaft sleeve (2), and a pin shaft (12) is provided on the outer surface of the shaft sleeve (2) and inserted into the pin hole.

6. The low-deflection horizontal kettle mechanical seal according to claim 1, characterized in that: The double-end sealing assembly includes an atmospheric side sealing assembly and a medium side sealing assembly, wherein the atmospheric side sealing assembly includes an atmospheric side spring seat (14) fixedly connected to the shaft sleeve (2), and the atmospheric side dynamic ring (17) is connected to the atmospheric side spring seat (14) through the atmospheric side spring (16); the sealing box (5) is connected to an atmospheric side static ring (15) on the side close to the bearing seat (6), and the atmospheric side static ring (15) contacts the end face of the atmospheric side dynamic ring (17), forming a set of sealing end faces on the atmospheric side.

7. A low-deflection horizontal kettle mechanical seal according to claim 6, characterized in that: The medium side sealing assembly comprises a medium side spring seat (19) fixed on the inner side of the sealing box (5), and a medium side static ring (20) is connected to the medium side spring seat (19) via a medium side spring (21); a medium side dynamic ring (22) is installed on the medium side of the shaft sleeve (2), and the medium side dynamic ring (22) contacts the end face of the medium side static ring (20), forming a set of sealing end faces on the medium side.

8. A low-deflection horizontal kettle mechanical seal according to claim 7, characterized in that: The contact end surfaces of the medium-side dynamic ring (22) and the medium-side static ring (20) are mutually matched and have the same size.

9. The low-deflection horizontal kettle mechanical seal according to claim 7, characterized in that: The atmospheric side of the main shaft (1) is also provided with a transmission ring (28), the atmospheric side end of the shaft sleeve (2) is provided with a transmission groove, one end of the transmission ring (28) is pressed against the outside of the main shaft (1), and the other end is pressed against the outside of the transmission groove.

10. The low-deflection mechanical seal for a horizontal kettle according to claim 9, characterized in that: The transmission ring (28) is a half-split structure, formed by embracing two half rings.

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