Roots vacuum pump sealing device

Abstract

The utility model discloses a Roots vacuum pump sealing device which comprises a vacuum pump, a static ring sealing structure and a moving ring sealing structure, the static ring sealing structure further comprises a static ring mechanical sealing cover, a shaft hole is also formed in the static ring mechanical sealing cover, and the static ring mechanical sealing cover is detachably connected to the outer side of a pump shell. A boss matched with a center hole of the pump shell is arranged on the rear side of the static ring mechanical seal cover in a protruding mode, a groove is formed in the boss, the static ring is inserted into the groove, and a static ring sealing ring is arranged between the front portion of the static ring and the side wall of the groove. A containing cavity is concavely formed in the front side of the mechanical seal base, and the movable ring is slidably connected into the containing cavity through a mechanical seal spring and always abuts against the rear end of the static ring through the mechanical seal spring. A containing groove communicated with a shaft hole of the movable ring is formed in the rear end of the movable ring, the movable ring sealing ring is installed in the containing groove, the static ring sealing ring and the movable ring sealing ring are both made of perfluoroether materials, and the cross section of each of the static ring sealing ring and the movable ring sealing ring is O-shaped. The split type design is adopted, segmented replacement can be achieved, the maintenance efficiency is improved, corrosion resistance is achieved, the sealing performance is good, and the service life is long.

Description

Technical Field

[0001] The utility model relates to the technical field of sealing structures, in particular to a sealing device for a Roots vacuum pump. Background Art

[0002] A good seal must be ensured between the rotating shaft and the gearbox of the Roots pump. There are gears, bearings, bearing seats, etc. in the gearbox, and the gears and bearings must be lubricated. After the lubricating oil lubricates the bearings, it is necessary to prevent the lubricating oil from deteriorating and leaking under the dynamic and static conditions, high temperature, and high corrosion of the rotating shaft, thereby damaging the vacuum pump. The traditional static ring seal structure and the machine seal cover are designed as an integrated design. When damaged, the integrated machine seal cover must be replaced, which is expensive, time-consuming and laborious. The dynamic ring mechanical seal is also fixed to the transmission shaft with bolts. When any small part is damaged, the entire vacuum pump unit casing must be disassembled for repair, which is too tiring and hard. In addition, most of the sealing rings are made of fluororubber or nitrile, which are not resistant to high temperatures and are easily damaged. On the other hand, in highly corrosive industries such as chemical industry, rubber is easily corroded and dissolved, thereby losing its sealing function, resulting in oil shortage in the equipment, and thus causing bearing damage. Therefore, there is an urgent need for a sealing device that is easy to disassemble and assemble, has a long service life and is corrosion-resistant. Utility Model Content

[0003] The utility model aims to solve the technical problems existing in the prior art, and particularly innovatively proposes a Roots vacuum pump sealing device with a split design, which can be replaced in sections, improves maintenance efficiency, is corrosion-resistant, has good sealing performance and a long service life.

[0004] In order to achieve the above-mentioned purpose, the utility model provides a Roots vacuum pump sealing device, including a vacuum pump, a static ring sealing structure and a dynamic ring sealing structure, the static ring sealing structure includes a static ring sealing ring and a static ring, the dynamic ring sealing structure includes a dynamic ring, a dynamic ring sealing ring, a mechanical seal spring and a mechanical seal base arranged in sequence from front to back, each component of the static ring sealing structure and the dynamic ring sealing structure is provided with an axial hole for a transmission shaft to pass through, the static ring sealing structure and the dynamic ring sealing structure are both sleeved on the transmission shaft, and the center hole on the pump housing of the vacuum pump for the transmission shaft to pass through is The aperture is larger than the outer diameter of the static ring sealing structure and the dynamic ring sealing structure, so that the static ring sealing structure and the dynamic ring sealing structure can be taken out or installed from the center hole. The static ring sealing structure also includes a static ring machine cover, and the static ring machine cover is also provided with an axial hole for the transmission shaft to pass through. The static ring machine cover is detachably connected to the outer side of the pump housing. The rear side of the static ring machine cover is convexly provided with a boss matching the center hole of the pump housing, and the boss is provided with a groove connected with its axial hole. The static ring is inserted into the groove, and a static ring sealing ring is provided between the front part of the static ring and the side wall of the groove;

[0005] The front side of the mechanical seal base is recessed with an accommodating cavity for accommodating a moving ring. The moving ring is slidably connected in the accommodating cavity through a mechanical seal spring, and the front end of the moving ring is always located outside the accommodating cavity. The moving ring is always against the rear end of the static ring through the mechanical seal spring; the rear end of the moving ring is provided with a accommodating groove connected to its axial hole, and the moving ring sealing ring is installed in the accommodating groove, and both the static ring sealing ring and the dynamic ring sealing ring are made of perfluoroether material, and the cross-sections of the static ring sealing ring and the dynamic ring sealing ring are both O-shaped.

[0006] In the above scheme: a circle of bolt mounting holes is arranged on the static ring machine cover around the shaft hole, and the static ring machine cover is detachably mounted with the pump casing through fixing bolts, so the structure is simple and the installation is convenient.

[0007] In the above scheme: the static ring is installed in the groove by press-fitting, which is simple to process and stable to install.

[0008] In the above scheme: the static ring and the dynamic ring are both made of alloy material with high hardness and wear resistance.

[0009] In the above scheme, a spring retaining ring is arranged between the mechanical seal spring and the dynamic ring, and the dynamic ring sealing ring is pressed against the receiving groove through the spring retaining ring, which can reduce the wear between the spring and the dynamic ring, prevent the dynamic ring sealing ring from slipping out, and improve the sealing performance.

[0010] In summary, the beneficial effects of the utility model are: the structure is simple and reasonable, easy to implement, the perfluoroether material has a long service life, strong corrosion resistance, good sealing effect, and can be applied to equipment in the chemical field. The static ring seal and the dynamic ring seal can form a radial sealing surface. The dynamic ring seal is combined with the static ring seal under the pressure of the machine seal spring to form an axial sealing surface. The sealing surface has good heat dissipation and excellent mechanical properties, which effectively prolongs the service life of the whole machine and reduces the maintenance frequency. Since each component of the sealing structure is a split design and can be replaced in sections, compared with the sealing structure that is integrated in the prior art, damaged parts can be replaced separately during maintenance, reducing maintenance costs and reducing workload. The static ring machine cover is detachably connected to the outside of the pump casing for easy disassembly. It is combined with the static ring seal structure and the dynamic ring seal structure as a jacket installation, which is convenient for taking out the static ring seal structure and the dynamic ring seal structure, and improving the efficiency of maintenance and replacement. The boss can block the center hole of the pump casing to improve the sealing effect. The stationary ring sealing ring and the dynamic ring sealing ring are respectively arranged at the front of the stationary ring and the rear end of the dynamic ring, so as to facilitate the removal of the stationary ring sealing ring and the dynamic ring sealing ring which play an important role in the sealing effect and ensure the sealing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is an exploded view of the utility model.

[0012] Figure 2 It is a schematic diagram of the utility model when installed.

[0013] Figure 3 yes Figure 2 A magnified schematic diagram of center A.

[0014] Figure 4 It is a schematic diagram of the static ring machine cover. DETAILED DESCRIPTION

[0015] The present invention will be further described below by way of embodiments and in conjunction with the accompanying drawings:

[0016] like Figure 1 to Figure 4 As shown, a Roots vacuum pump sealing device includes a vacuum pump, a stationary ring sealing structure and a dynamic ring sealing structure. The stationary ring sealing structure and the dynamic ring sealing structure are both mounted on a transmission shaft 10. The diameter of the center hole on the vacuum pump housing 11 through which the transmission shaft 10 passes is larger than the outer diameter of the stationary ring sealing structure and the dynamic ring sealing structure, so that the stationary ring sealing structure and the dynamic ring sealing structure can be taken out or installed from the center hole. Each component of the stationary ring sealing structure and the dynamic ring sealing structure is provided with an axial hole through which the transmission shaft 10 passes.

[0017] The stationary ring sealing structure includes a stationary ring machine cover 1, a stationary ring sealing ring 2 and a stationary ring 3. The stationary ring machine cover 1 is also provided with an axial hole for the transmission shaft 10 to pass through. The stationary ring machine cover 1 is provided with a circle of bolt mounting holes around the axial hole, and is detachably mounted with the pump housing 11 through fixing bolts 9, with a simple structure and convenient installation.

[0018] The rear side of the static ring cover 1 is convexly provided with a boss 1a matching the center hole of the pump housing 11. The boss 1a is provided with a groove 1b connected to its shaft hole, and the static ring 3 is press-fitted and installed in the groove 1b, which is simple to process and stable to install. A static ring seal 2 is provided between the front part of the static ring 3 and the side wall of the groove 1b.

[0019] The dynamic ring sealing structure includes a dynamic ring 4, a dynamic ring sealing ring 5, a spring retaining ring 6, a mechanical seal spring 7 and a mechanical seal base 8 which are arranged in sequence from front to back. A receiving cavity for receiving the dynamic ring 4 is recessed on the front side of the mechanical seal base 8, and the dynamic ring 4 is slidably connected in the receiving cavity through the mechanical seal spring 7. The front end of the dynamic ring 4 is always located outside the receiving cavity, and the dynamic ring 4 is always against the rear end of the static ring 3 through the mechanical seal spring 7. The rear end of the dynamic ring 4 is provided with a receiving groove 4a connected to its axial hole, and the dynamic ring sealing ring 5 is installed in the receiving groove 4a. In order to reduce the wear between the dynamic ring 4 and the mechanical seal spring 7, a spring retaining ring 6 is provided between the dynamic ring 4 and the mechanical seal spring 7. The inner diameter of the spring retaining ring 6 is smaller than the outer diameter of the dynamic ring sealing ring 5, and the dynamic ring sealing ring 5 is pressed against the receiving groove 4a through the spring retaining ring 6.

[0020] The static ring seal ring 2 and the dynamic ring seal ring 5 are both made of perfluoroether material, and the cross-sections of the static ring seal ring 2 and the dynamic ring seal ring 5 are both O-shaped. The static ring 3 and the dynamic ring 4 are both made of alloy material, with high hardness and wear resistance.

[0021] When disassembling for maintenance, first remove the coupling 12, remove the fixing bolts 9 of the static ring machine cover 1, and take out the static ring machine cover 1. Take out the components of the dynamic ring seal structure in turn and replace the damaged parts. There is no need to disassemble the entire Roots pump to replace the seal structure, which saves maintenance time and improves maintenance efficiency.

Claims

1. A Roots vacuum pump sealing device, comprising a vacuum pump, a stationary ring sealing structure and a dynamic ring sealing structure, wherein the stationary ring sealing structure comprises a stationary ring sealing ring (2) and a stationary ring (3), and the dynamic ring sealing structure comprises a dynamic ring (4), a dynamic ring sealing ring (5), a mechanical seal spring (7) and a mechanical seal base (8) arranged in sequence from front to back, and each component of the stationary ring sealing structure and the dynamic ring sealing structure is provided with an axial hole for a transmission shaft (10) to pass through, characterized in that: The static ring sealing structure and the dynamic ring sealing structure are both sleeved on the transmission shaft (10); the diameter of the center hole on the pump housing (11) of the vacuum pump for the transmission shaft (10) to pass through is larger than the outer diameter of the static ring sealing structure and the dynamic ring sealing structure, so that the static ring sealing structure and the dynamic ring sealing structure can be taken out or installed from the center hole; the static ring sealing structure also includes a static ring machine cover (1); the static ring machine cover (1) is also provided with an axial hole for the transmission shaft (10) to pass through; the static ring machine cover (1) is detachably connected to the outer side of the pump housing (11); the rear side of the static ring machine cover (1) is convexly provided with a boss (1a) matching the center hole of the pump housing (11); the boss (1a) is provided with a groove (1b) connected with its axial hole; the static ring (3) is inserted into the groove (1b); a static ring sealing ring (2) is provided between the front part of the static ring (3) and the side wall of the groove (1b); The front side of the mechanical seal base (8) is recessed with an accommodating cavity for accommodating a moving ring (4); the moving ring (4) is slidably connected in the accommodating cavity via a mechanical seal spring (7), and the front end of the moving ring (4) is always located outside the accommodating cavity; the moving ring (4) is always in contact with the rear end of the static ring (3) via the mechanical seal spring (7); the rear end of the moving ring (4) is provided with an accommodating groove (4a) connected to its axial hole, and the moving ring sealing ring (5) is installed in the accommodating groove (4a); the static ring sealing ring (2) and the moving ring sealing ring (5) are both made of perfluoroether material, and the cross-sections of the static ring sealing ring (2) and the moving ring sealing ring (5) are both O-shaped.

2. A Roots vacuum pump sealing device according to claim 1, characterized in that: The static ring machine cover (1) is provided with a circle of bolt mounting holes around the shaft hole, and is detachably mounted with the pump casing (11) via fixing bolts (9).

3. A Roots vacuum pump sealing device according to claim 1, characterized in that: The stationary ring (3) is installed in the groove (1b) by press fitting.

4. A Roots vacuum pump sealing device according to claim 3, characterized in that: The stationary ring (3) and the dynamic ring (4) are both made of alloy material.

5. A Roots vacuum pump sealing device according to claim 1, characterized in that: A spring retaining ring (6) is provided between the mechanical seal spring and the dynamic ring, and the dynamic ring sealing ring (5) is pressed against the accommodating groove (4a) through the spring retaining ring (6).

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