Sealing design structure of chemical centrifugal pump

Abstract

The utility model discloses a sealing design structure of a chemical centrifugal pump. The sealing design structure comprises a motor; the pump body is arranged at one end of the motor, a driving shaft of the motor extends into the pump body, an impeller is arranged on the driving shaft, and the impeller is located in the pump body; the pump cover is arranged between the pump body and the motor, a plurality of back blades are arranged on the side, close to the pump body, of the pump cover, a machine seal is arranged on one side of the pump cover, the machine seal is an external machine seal, and a sealing ring is arranged between the machine seal and the pump cover. Compared with the prior art, the centrifugal pump can solve the problem of material leakage caused by the fact that a mechanical seal is easy to damage in the process of pumping frozen saline water materials by the centrifugal pump.

Description

Technical Field

[0001] The utility model belongs to the field of centrifugal pumps, and in particular relates to a sealing design structure of a chemical centrifugal pump. Background Art

[0002] A centrifugal pump is a pump that transports liquids by the centrifugal force generated by the rotation of the impeller. It is mainly composed of an impeller, a pump body, a pump shaft, bearings, etc. Its main features include: compact structure, wide flow and head range, uniform flow, stable operation, low vibration, and low equipment installation, maintenance and repair costs.

[0003] At present, the temperature of materials pumped by centrifugal pumps is in the range of -20℃-80℃. The main component is frozen brine, which also contains some abrasive particles. The pumped frozen brine is mainly a salt-containing medium. Due to the change in temperature, the solute precipitates and settles on the sealing end face, causing severe wear or blockage. The medium temperature is low, and the moisture in the atmosphere will freeze on the sealing end face to accelerate the wear of the friction pair. If it is pumped by an on-site chemical centrifugal pump, leakage will occur on-site after two months of use, affecting the normal production of the factory. Utility Model Content

[0004] The utility model aims to provide a chemical centrifugal pump seal design structure in order to solve the problem that the mechanical seal is easily damaged during the process of pumping frozen brine materials by the centrifugal pump, resulting in material leakage.

[0005] In order to achieve the above purpose, the utility model adopts the following technical scheme: a chemical centrifugal pump seal design structure, which includes:

[0006] Motor;

[0007] A pump body, wherein the pump body is arranged at one end of the motor, a driving shaft of the motor extends into the pump body, an impeller is arranged on the driving shaft, and the impeller is located in the pump body;

[0008] A pump cover is arranged between the pump body and the motor, a plurality of back blades are arranged on the side of the pump cover close to the pump body, an organic seal is arranged on one side of the pump cover, the organic seal is an external organic seal, and a sealing ring is arranged between the organic seal and the pump cover.

[0009] As a further description of the above technical solution:

[0010] The mechanical seal includes a dynamic ring seat, a dynamic ring and a static ring. The dynamic ring seat, the dynamic ring and the static ring are located on the drive shaft. The sealing ring is arranged between the static ring and the pump cover. The dynamic ring is arranged at one end of the static ring close to the motor, and the dynamic ring seat is arranged at one end of the dynamic ring.

[0011] As a further description of the above technical solution:

[0012] The sealing ring is a perfluoroether sealing ring.

[0013] As a further description of the above technical solution:

[0014] The material of the mechanical seal is tungsten carbide.

[0015] As a further description of the above technical solution:

[0016] The back blade is an arc-shaped back blade.

[0017] As a further description of the above technical solution:

[0018] A plurality of balancing holes are arranged on the rear cover plate of the impeller.

[0019] As a further description of the above technical solution:

[0020] The balancing hole is a U-shaped balancing hole.

[0021] As a further description of the above technical solution:

[0022] A water retaining ring is arranged on one side of the mechanical seal close to the motor.

[0023] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0024] 1. In the utility model, an external mechanical seal is adopted, which greatly reduces the accumulation of materials at the mechanical seal. The design of the back blades at the pump cover blocks the material with particles outside the mechanical seal during operation, thereby extending the service life of the mechanical seal. The output shaft of the motor is used as the pump shaft to reduce the problem of eccentricity between the motor and the pump head when connected.

[0025] 2. In the utility model, the pump cover is designed with a back blade. The material of the pump cover is 316L, and the entire structure is welded. At the same time, a curved back blade structure is added. This design allows the fluid in the pump cover and the impeller cavity to be thrown away in all directions during the operation of the pump under the action of the curved back blade, and the material will not accumulate at the machine seal, so that the machine seal is always in a relatively clean state.

[0026] 3. In the utility model, a U-shaped balancing hole is added to the impeller rear cover. The balancing hole is added here to balance the axial force generated by the centrifugal pump during operation to ensure the smooth operation, and the particle-carrying sediment at the pump cover and the impeller rear cover can be brought into the impeller inlet through the pressure difference, so that the particle-carrying sediment cannot accumulate at the impeller rear cover. This is also the working position of the mechanical seal. Without the accumulation of particles, the mechanical seal runs very cleanly, ensuring the full lubrication of the mechanical seal. At the same time, the wear of the dynamic and static ring surfaces of the mechanical seal is reduced, which greatly extends the service life of the mechanical seal. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 The schematic diagram of the seal design structure of a chemical centrifugal pump is shown in FIG.

[0029] Figure 2 The figure is a schematic diagram of the structure of a middle pump cover of a chemical centrifugal pump sealing design structure.

[0030] Figure 3 The figure is a cross-sectional view of a middle pump cover of a chemical centrifugal pump sealing design structure.

[0031] Figure 4 This is a schematic diagram of the structure of the impeller in a chemical centrifugal pump seal design structure.

[0032] Legend:

[0033] 1. Motor; 2. Pump body; 3. Drive shaft; 4. Impeller; 5. Pump cover; 6. Back blade; 7. Mechanical seal; 8. Balance hole; 9. Water retaining ring. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0035] See also Figure 1-4 The utility model provides a technical solution: a chemical centrifugal pump sealing design structure, which includes:

[0036] Motor 1;

[0037] A pump body 2, wherein the pump body 2 is arranged at one end of the motor 1, a driving shaft 3 of the motor 1 extends into the pump body 2, an impeller 4 is arranged on the driving shaft 3, and the impeller 4 is located in the pump body 2;

[0038] A pump cover 5 is provided between the pump body 2 and the motor 1 . A plurality of back blades 6 are provided on a side of the pump cover 5 close to the pump body 2 . An organic seal 7 is provided on one side of the pump cover 5 . The organic seal 7 is an external organic seal 7 . A sealing ring is provided between the organic seal 7 and the pump cover 5 .

[0039] The mechanical seal 7 includes a dynamic ring seat, a dynamic ring and a static ring. The dynamic ring seat, the dynamic ring and the static ring are located on the drive shaft 3. The sealing ring is arranged between the static ring and the pump cover 5. The dynamic ring is arranged at one end of the static ring close to the motor 1, and the dynamic ring seat is arranged at one end of the dynamic ring.

[0040] The machine seal adopts an external mechanical seal, the machine seal material is tungsten carbide, and the sealing ring is made of perfluoroether material. The static ring part of the machine seal extends into the pump cover cavity, and the dynamic ring and the dynamic ring seat are on the atmosphere side and do not contact the material. Only the static ring in the machine seal is in contact with the material, and the material is tungsten carbide. At the same time, the contact part between the static ring and the pump cover is a perfluoroether sealing ring to ensure the fit between the machine seal and the pump cover, and at the same time play an anti-corrosion and sealing effect, which greatly improves the service life of the seal.

[0041] The sealing ring is a perfluoroether sealing ring, which has an anti-corrosion effect and increases the service life.

[0042] The material of the mechanical seal 7 is tungsten carbide.

[0043] The back blade 6 is an arc-shaped back blade. The back blade is added to the pump cover side, and it is an arc-shaped design, so that during operation, all particles will be moved away from the center of the shaft under the action of centrifugal force, and there will be no accumulation of foreign particles on the mechanical seal side, thereby maintaining a clean operating environment for the mechanical seal.

[0044] The rear cover plate of the impeller 4 is provided with a plurality of balancing holes 8. The balancing holes 8 are U-shaped balancing holes. Specifically, six balancing holes are provided. The impeller adopts the balancing hole opening process, which can balance the axial force and return the material with particles to the impeller inlet. The impeller balancing hole is designed in a U-shaped design, which can more conveniently press the material with particles into the inlet from the high-pressure area of ​​the impeller outlet through the pressure difference during operation to prevent the accumulation of particles on the shaft.

[0045] A water retaining ring 9 is provided on one side of the mechanical seal 7 close to the motor 1 .

[0046] Working principle: In the utility model, all flow-through parts are made of 316L material, which is more resistant to the corrosion of salt water. The machine seal adopts an external mechanical seal, the machine seal material is tungsten carbide, and the sealing ring is made of perfluoroether material. The static ring part of the machine seal extends into the pump cover cavity, and the dynamic ring and the dynamic ring seat are on the atmosphere side and do not contact the material. Only the static ring in the machine seal is in contact with the material, and the material is tungsten carbide. At the same time, the contact part between the static ring and the pump cover is a perfluoroether sealing ring to ensure the fit between the machine seal and the pump cover, and at the same time play an anti-corrosion and sealing effect, which greatly improves the service life of the seal. Sealing blades are installed on the inside of the pump cover. Since the material contains solid particles and crystal precipitates, the particles will be attached to the vicinity of the static ring surface of the mechanical seal due to the centrifugal force during the operation of the pump, which will wear the static ring of the mechanical seal over time. In order to prevent this from happening, a back blade is added to the pump cover side, and it is an arc-shaped design. In this way, during operation, all particles will be moved away from the center of the shaft under the action of centrifugal force, and there will be no accumulation of impurity particles on the mechanical seal side, thereby maintaining a clean operating environment for the mechanical seal. The impeller adopts an open balancing hole process, which can balance the axial force while also returning the material with particles to the impeller inlet. The impeller balancing hole is designed in a U-shaped design, which can more conveniently press the material with particles into the inlet from the high-pressure area of ​​the impeller outlet through the pressure difference during operation to prevent the accumulation of particles on the shaft. At the same time, the direct connection structure design is adopted, without the motor coupling, and the design concept of a single shaft ensures the concentricity of the shaft, greatly ensuring the stability of the mechanical seal during operation. Through the implementation of these design concepts, the service life of the mechanical seal is extended. Through the above improvements, the use effect after the transformation has been achieved at the user's site, and there has been no leakage at the site. The use effect is excellent, and it has not been shut down until the whole plant is overhauled.

[0047] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A chemical centrifugal pump seal design structure, characterized in that: include: Motor; A pump body, wherein the pump body is arranged at one end of the motor, a driving shaft of the motor extends into the pump body, an impeller is arranged on the driving shaft, and the impeller is located in the pump body; A pump cover is arranged between the pump body and the motor, a plurality of back blades are arranged on the side of the pump cover close to the pump body, an organic seal is arranged on one side of the pump cover, the organic seal is an external organic seal, and a sealing ring is arranged between the organic seal and the pump cover.

2. A chemical centrifugal pump seal design structure according to claim 1, characterized in that: The mechanical seal includes a dynamic ring seat, a dynamic ring and a static ring. The dynamic ring seat, the dynamic ring and the static ring are located on the drive shaft. The sealing ring is arranged between the static ring and the pump cover. The dynamic ring is arranged at one end of the static ring close to the motor, and the dynamic ring seat is arranged at one end of the dynamic ring.

3. A chemical centrifugal pump seal design structure according to claim 1, characterized in that: The sealing ring is a perfluoroether sealing ring.

4. A chemical centrifugal pump seal design structure according to claim 1, characterized in that: The material of the mechanical seal is tungsten carbide.

5. A chemical centrifugal pump seal design structure according to claim 1, characterized in that: The back blade is an arc-shaped back blade.

6. A chemical centrifugal pump seal design structure according to claim 1, characterized in that: A plurality of balancing holes are arranged on the rear cover plate of the impeller.

7. A chemical centrifugal pump seal design structure according to claim 6, characterized in that: The balancing hole is a U-shaped balancing hole.

8. A chemical centrifugal pump seal design structure according to claim 1, characterized in that: A water retaining ring is arranged on one side of the mechanical seal close to the motor.

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