Interstage seal structure for a multi-stage slurry pump

Abstract

The utility model discloses a kind of interstage sealing structure of multistage slurry pump, including primary pump body and secondary pump body, the same pump shaft is rotatably installed in the inside of primary pump body and secondary pump body and passes through, the inside of primary pump body and secondary pump body is respectively provided with primary cavity and secondary cavity, the outer surface of the pump shaft is respectively fixedly connected with primary impeller and secondary impeller in the inside of primary cavity, secondary cavity, interstage guard plate is arranged between primary impeller and secondary impeller;Compared with prior art, the ceramic high hardness of anti-abrasion sleeve can better resist the abrasion of slurry particle, improve the service life of guard plate, the labyrinth groove with comb structure on the inner surface of anti-abrasion sleeve can consume the kinetic energy of leakage slurry, improve the pressure relief condition, thereby reduce the time loss and economic loss caused by frequent shutdown and replacement of standby machine, simultaneously extend wear part replacement cycle, reduce the use cost of user.

Description

Technical Field

[0001] This utility model relates to the field of multi-stage slurry pump technology, specifically to an interstage sealing structure for a multi-stage slurry pump. Background Technology

[0002] A filter press feed pump with two-stage impellers connected in series is a mechanical device that increases the energy of a solid-liquid mixture through rotation, converting electrical energy into the kinetic and potential energy of the medium. It is commonly used in mineral processing systems for feeding washed or reacted raw material waste through filter pressing, or for long-distance tailings transportation. This type of operation requires high flow rate and low pressure at the initial feeding stage, and low flow rate and high pressure at the end of the feeding stage (when the slurry is about to fill the filter bag). The two-stage impellers connected in series effectively meet these requirements.

[0003] The two impellers are connected in series, separated by an interstage liner to form a primary cavity and a secondary cavity. The interstage seal between the two cavities is ensured by a small gap formed between the inner diameter of the interstage liner and the outer diameter of the secondary impeller hub.

[0004] Currently, during pump impeller rotation, the relative flow velocity is high at the impeller's outer diameter. Besides most solid particles in the slurry being discharged from the pump outlet, some particles inevitably accumulate in areas with relatively lower flow velocities, namely near the shaft, specifically in the small gap between the two-stage cavities. When particles enter this gap, it causes wear on metal parts, resulting in a short service life for the interstage liner, leading to pressure leakage between the two stages. Consequently, the pump outlet pressure fails to meet requirements, necessitating liner replacement.

[0005] The pressure difference between the two stages of this type of pump is unavoidable, and wear cannot be eliminated; it can only be counteracted. Both the interstage guard plate and the second-stage impeller are wear-resistant metal parts, and relying solely on the wear resistance of the metal materials to combat the erosion of the slurry results in an insufficient service life. Therefore, this invention proposes an interstage sealing structure for a multi-stage slurry pump. Utility Model Content

[0006] The purpose of this invention is to provide an interstage sealing structure for a multistage slurry pump to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, this utility model provides the following technical solution: an interstage sealing structure for a multistage slurry pump, comprising a primary pump body and a secondary pump body, wherein the same pump shaft is rotatably mounted through the primary and secondary pump bodies, and a primary cavity and a secondary cavity are respectively provided inside the primary and secondary pump bodies. A primary impeller and a secondary impeller are fixedly connected to the outer surface of the pump shaft inside the primary cavity and the secondary cavity, respectively. An interstage guard plate is provided between the primary impeller and the secondary impeller, and an anti-wear sleeve is fixedly installed on the inner surface of the interstage guard plate, and the anti-wear sleeve is fitted onto the outer surface of the secondary impeller on the side closest to the pump shaft.

[0008] As a preferred technical solution of this utility model, the anti-wear sleeve is a ceramic anti-wear sleeve.

[0009] As a preferred technical solution of this utility model, the inner surface of the anti-wear sleeve is provided with a labyrinth groove with a comb-shaped cross-section.

[0010] As a preferred technical solution of this utility model, a pressure plate is provided on the outer surface of the anti-wear sleeve near the first-stage impeller, and the pressure plate is fixedly connected to the interstage guard plate by fasteners.

[0011] As a preferred technical solution of this utility model, a gasket is provided between the pressure plate and the anti-wear sleeve.

[0012] As a preferred technical solution of this utility model, the outer surface of the anti-wear sleeve is provided with a positioning inclined part on the side near the interstage guard plate, and the outer surface of the interstage guard plate is provided with a positioning inclined part that matches it on the side near the anti-wear sleeve.

[0013] As a preferred technical solution of this utility model, the top of the primary pump body is provided with a primary inlet, and the bottom of the primary pump body is provided with a primary outlet. A conveying pipe is installed at the bottom of the primary outlet. The top of the secondary pump body is provided with a secondary outlet, and the side of the secondary pump body away from the primary pump body is provided with a secondary inlet. The end of the conveying pipe away from the primary outlet is installed on the secondary inlet.

[0014] As a preferred technical solution of this utility model, the outer surface of the interstage guard plate is fixedly connected to both the primary pump body and the secondary pump body.

[0015] As a preferred technical solution of this utility model, a first-stage protective plate is provided inside the first-stage pump body, and a second-stage protective plate is provided inside the second-stage pump body.

[0016] Compared with the prior art, the beneficial effects of this utility model are: This utility model discloses an interstage sealing structure for a multistage slurry pump. After structural adjustment, the high hardness of the ceramic anti-wear sleeve can effectively resist the abrasion of slurry particles, thus improving the service life of the protective plate. It is fixed to the interstage protective plate by gaskets and pressure plates, avoiding the risk of the ceramic sleeve breaking due to impact from rigid connections. The pressure plate is made of wear-resistant steel, which can improve wear resistance. The inner surface of the anti-wear sleeve has a labyrinth groove with a comb-like structure, which can consume the kinetic energy of leaking slurry and improve the pressure relief situation. This reduces the time and economic losses caused by frequent shutdowns and replacement of backup equipment, while extending the replacement cycle of worn parts and reducing the user's operating costs.

[0017] Other features and advantages of this invention will be described in detail in the following specific embodiments. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 For the present utility model Figure 1 Enlarged structural diagram at point A; Figure 3 A schematic diagram of the internal structure of a multi-stage slurry pump before improvements to existing technology; Figure 4 This is an external side view of a multi-stage slurry pump before its technological improvement. Figure 5 for Figure 3 Enlarged schematic diagram of the structure at point B.

[0019] In the diagram: 10. Primary pump body; 11. Primary inlet; 12. Primary outlet; 13. Primary guard plate; 14. Primary impeller; 15. Primary cavity; 20. Secondary pump body; 21. Secondary inlet; 22. Secondary outlet; 23. Secondary guard plate; 24. Secondary impeller; 25. Secondary cavity; 30. Delivery pipe; 40. Interstage guard plate; 41. Fastener; 42. Pressure plate; 43. Gasket; 44. Anti-wear sleeve; 45. Positioning slope; 46. Interstage clearance; 50. Pump shaft. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] In the description of this utility model, it should be noted that the terms "vertical", "up", "down", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0022] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0023] like Figures 3-5 It is known that in traditional multistage slurry pumps, only an interstage liner 40 is installed between the primary pump body 10 and the secondary pump body 20. The interstage seal between the primary chamber 15 and the secondary chamber 25 is ensured by the interstage gap 46 formed by the inner diameter of the interstage liner 40 and the outer diameter of the hub of the secondary impeller 24. The interstage liner 40 is generally made of cast iron, which is not durable enough. During use, the slurry is pressurized by the primary impeller 14 and enters the secondary impeller 24, and is then pressurized by the secondary impeller 24. The pressure in the entire secondary chamber 25 is much higher than that in the primary chamber 15. This pressure difference pushes the slurry in the secondary chamber 25 to "drill" into the primary chamber 15 through the interstage gap 46. As a result, the relative velocity at this point is very high under the action of the pressure difference, which leads to accelerated wear, severe interstage pressure leakage, and the pump outlet pressure failing to meet the requirements, necessitating the replacement of the interstage liner 40.

[0024] Please see Figures 1-2In this embodiment, an interstage sealing structure for a multi-stage slurry pump is provided, including a primary pump body 10 and a secondary pump body 20. A common pump shaft 50 is rotatably mounted through both the primary pump body 10 and the secondary pump body 20. A primary cavity 15 and a secondary cavity 25 are respectively provided inside the primary pump body 10 and the secondary pump body 20. A pressure difference exists between the fluid in the primary cavity 15 and the fluid in the secondary cavity 25. A primary impeller 14 and a secondary impeller 24 are fixedly connected to the outer surface of the pump shaft 50 inside the primary cavity 15 and the secondary cavity 25, respectively. An interstage guard plate 40 is provided between the pump bodies. The outer surface of the interstage guard plate 40 is fixedly connected to both the primary pump body 10 and the secondary pump body 20. A primary guard plate 13 is provided inside the primary pump body 10, and a secondary guard plate 23 is provided inside the secondary pump body 20. A primary inlet 11 is provided at the top of the primary pump body 10, and a primary outlet 12 is provided at the bottom of the primary pump body 10. A delivery pipe 30 is installed at the bottom of the primary outlet 12. A secondary outlet 22 is provided at the top of the secondary pump body 20, and a secondary inlet 21 is provided on the side of the secondary pump body 20 away from the primary pump body 10. The delivery pipe 30 is located away from the primary outlet 11. One end of the slurry is installed on the secondary inlet 21. During operation, the slurry enters the primary chamber 15 through the primary inlet 11. Under the action of the primary impeller 14, the slurry is transported to the primary outlet 12. Then, the slurry enters the secondary inlet 21 of the secondary pump body 20 through the conveying pipe 30. After that, the slurry enters the secondary chamber 25 and is discharged from the secondary outlet 22 under the action of the secondary impeller 24. An anti-wear sleeve 44 is fixedly installed on the inner surface of the interstage guard plate 40. The anti-wear sleeve 44 is fitted on the outer surface of the secondary impeller 24 near the pump shaft 50. The inner surface of the anti-wear sleeve 44 is provided with a comb-shaped cross-section. The labyrinth groove structure, specifically, the anti-wear sleeve 44 is made of silicon carbide ceramic. The high hardness of the ceramic resists the abrasion of slurry particles, replacing the traditional metal wear parts. This solves the problem of insufficient anti-corrosion performance of the original structure. Furthermore, the labyrinth groove of the comb-like structure of the anti-wear sleeve 44 can form a structure similar to the labyrinth groove in a labyrinth seal at the outer diameter of the secondary impeller hub. The labyrinth groove of the anti-wear sleeve 44 consumes the kinetic energy of the leaking slurry (when the leaking slurry flows through the labyrinth groove, vortices are generated due to poor flow, and the energy of the fluid is consumed), improving the pressure relief situation and thus extending the replacement cycle of the wear parts.

[0025] In this embodiment, a pressure plate 42 is provided on the outer surface of the anti-wear sleeve 44 near the first-stage impeller 14, and the pressure plate 42 is fixedly connected to the interstage guard plate 40 by fasteners 41. Specifically, the pressure plate 42 is made of wear-resistant steel to improve wear resistance. The fasteners 41 can be screws.

[0026] In this embodiment, a gasket 43 is provided between the pressure plate 42 and the anti-wear sleeve 44. Specifically, the gasket 43 is a rubber gasket.

[0027] In this embodiment, a positioning inclined portion 45 is provided on the outer surface of the anti-wear sleeve 44 near the interstage guard plate 40, and a positioning inclined portion adapted to it is provided on the outer surface of the interstage guard plate 40 near the anti-wear sleeve 44. The positioning inclined portion 45 and the positioning inclined portion can make the installation of the anti-wear sleeve 44 more accurate and quick. This inclined self-positioning structure is simple to install without complicated operation, has relatively low fitting accuracy, and requires less fine processing time.

[0028] In summary, after the structural adjustments of this utility model, the high hardness of the ceramic in the anti-wear sleeve 44 can effectively resist the abrasion of slurry particles, thus improving the service life of the protective plate. The sleeve is fixed to the interstage protective plate by gaskets and pressure plates, avoiding the risk of the ceramic sleeve breaking due to impact from rigid connections. The pressure plate, made of wear-resistant steel, improves wear resistance. The inner surface of the anti-wear sleeve has a labyrinth groove with a comb-like structure, which can dissipate the kinetic energy of leaking slurry, improving pressure relief. This reduces time and economic losses caused by frequent downtime and replacement of backup equipment, while extending the replacement cycle of worn parts and reducing user operating costs.

[0029] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. An interstage sealing structure for a multi-stage slurry pump, characterized in that, The pump includes a primary pump body (10) and a secondary pump body (20). The same pump shaft (50) is rotatably installed inside the primary pump body (10) and the secondary pump body (20). The primary pump body (10) and the secondary pump body (20) are respectively provided with a primary cavity (15) and a secondary cavity (25). The outer surface of the pump shaft (50) is located inside the primary cavity (15) and the secondary cavity (25) and is respectively fixedly connected to a primary impeller (14) and a secondary impeller (24). An interstage guard plate (40) is provided between the primary impeller (14) and the secondary impeller (24). An anti-wear sleeve (44) is fixedly installed on the inner surface of the interstage guard plate (40) and is sleeved on the outer surface of the secondary impeller (24) near the pump shaft (50).

2. The interstage sealing structure of a multi-stage slurry pump according to claim 1, characterized in that, The wear-resistant sleeve (44) is a ceramic wear-resistant sleeve.

3. The interstage sealing structure of a multi-stage slurry pump according to claim 1, characterized in that, The inner surface of the anti-wear sleeve (44) is provided with a labyrinth groove with a comb-shaped cross-section.

4. The interstage sealing structure of a multi-stage slurry pump according to claim 2, characterized in that, The wear-resistant sleeve (44) has a pressure plate (42) on its outer surface near the first-stage impeller (14), and the pressure plate (42) is fixedly connected to the interstage guard plate (40) by fasteners (41).

5. The interstage sealing structure of a multi-stage slurry pump according to claim 4, characterized in that, A gasket (43) is provided between the pressure plate (42) and the anti-wear sleeve (44).

6. The interstage sealing structure of a multi-stage slurry pump according to claim 1, characterized in that, The outer surface of the anti-wear sleeve (44) is provided with a positioning inclined part (45) on the side near the interstage guard plate (40), and the outer surface of the interstage guard plate (40) is provided with a positioning inclined part that matches it on the side near the anti-wear sleeve (44).

7. The interstage sealing structure of a multi-stage slurry pump according to claim 1, characterized in that, The first-stage pump body (10) has a first-stage inlet (11) at the top and a first-stage outlet (12) at the bottom. A delivery pipe (30) is installed at the bottom of the first-stage outlet (12). The second-stage pump body (20) has a second-stage outlet (22) at the top. A second-stage inlet (21) is provided on the side of the second-stage pump body (20) away from the first-stage pump body (10). The end of the delivery pipe (30) away from the first-stage outlet (12) is installed on the second-stage inlet (21).

8. The interstage sealing structure of a multi-stage slurry pump according to claim 1, characterized in that, The outer surface of the interstage guard plate (40) is fixedly connected to both the primary pump body (10) and the secondary pump body (20).

9. The interstage sealing structure of a multi-stage slurry pump according to claim 1, characterized in that, The first-stage pump body (10) is provided with a first-stage guard plate (13), and the second-stage pump body (20) is provided with a second-stage guard plate (23).

Images