Submerged centrifugal pump structure

Abstract

The utility model discloses a kind of liquid below centrifugal pump structures, comprising: drive section, it includes motor and motor frame, coupling is provided in motor frame, motor is connected drive shaft by coupling;Liquid outlet is provided on liquid outlet section, liquid outlet section is fixedly installed in motor frame lower side, shaft seal structure is provided between liquid outlet section and motor frame, shaft seal structure includes K-shaped sealing ring, vice impeller arranged in order from top to bottom along the direction of drive shaft axis, vice impeller is sleeved on drive shaft;Liquid inlet section, it is connected liquid outlet section by intermediate connecting pipe, liquid inlet section includes front section, middle section, impeller and annular guide vane, liquid inlet is provided on front section, middle section is installed on front section, impeller is arranged in middle section, impeller is sleeved on drive shaft, annular guide vane is provided on the outside of impeller.The utility model compared with prior art, solve the problem that existing liquid below centrifugal pump structure cannot cope with large flow, high pressure working condition and poor axial sealing.

Description

Technical Field

[0001] This utility model relates to the field of submersible centrifugal pump technology, and in particular to a submersible centrifugal pump structure. Background Technology

[0002] Submersible centrifugal pumps are vertically mounted centrifugal pumps widely used in industrial fields. They are characterized by operating with the pump body immersed in the liquid being transported.

[0003] Existing submersible centrifugal pumps typically employ a spiral-rotated volute chamber for the outlet water chamber, allowing them to be used in standard processes and with appropriate head. The submersible depth can reach approximately 5 meters, meeting the requirements of conventional operating conditions.

[0004] When encountering operating conditions with large parameters and high flow rates, due to the inherent structural problem of the water outlet position on the side of the spiral volute chamber, the submersible pump unit will experience vibration, noise, and swaying due to excessive pressure on the side blades under high operating parameters. This can lead to damage to the bearings, prevent the unit from operating continuously, and affect the on-site production capacity.

[0005] In addition, existing submersible centrifugal pumps are prone to shallow installation slots on site, which can cause some of the effluent material to escape axially and enter the bearing area due to pressure issues during operation. Material entering the bearing area can easily damage the bearing, leading to the shutdown of the submersible pump unit. Utility Model Content

[0006] The purpose of this invention is to provide a submersible centrifugal pump structure to solve the problems of existing submersible centrifugal pump structures being unable to cope with high flow and high pressure conditions and having poor axial sealing.

[0007] To achieve the above objectives, this utility model adopts the following technical solution: a submersible centrifugal pump structure, comprising:

[0008] The drive section includes a motor and a motor frame. A coupling is installed inside the motor frame, and the motor is connected to the drive shaft through the coupling.

[0009] The liquid outlet section is provided with a liquid outlet. The liquid outlet section is fixedly installed on the lower side of the motor frame. A shaft seal structure is provided between the liquid outlet section and the motor frame. The shaft seal structure includes a K-shaped sealing ring and a secondary impeller arranged sequentially from top to bottom along the drive shaft axis. The secondary impeller is sleeved on the drive shaft.

[0010] The liquid inlet section is connected to the liquid outlet section through an intermediate pipe. The liquid inlet section includes a front section, a middle section, an impeller, and an annular guide vane. The front section is provided with a liquid inlet, the middle section is installed on the front section, the impeller is located inside the middle section, the impeller is mounted on the drive shaft, and an annular guide vane is provided on the outside of the impeller.

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

[0012] The liquid inlet has a cone-shaped structure that is narrow at the top and wide at the bottom.

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

[0014] A bearing housing is provided inside the liquid inlet. The outer ring of the sliding bearing is fixedly installed inside the bearing housing, and the inner ring of the sliding bearing is fitted onto the drive shaft. A bushing is provided between the inner ring of the sliding bearing and the drive shaft.

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

[0016] Several circumferentially arranged stiffening plates are provided on the outer side of the bearing housing, and the stiffening plates are fixedly installed on the inner wall of the liquid inlet.

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

[0018] The middle section is equipped with an intermediate flow channel that connects to the intermediate pipe, and several circumferentially arranged arc-shaped blades are installed in the intermediate flow channel.

[0019] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0020] 1. In this utility model, the influence of pumping large flow rates and high pressures on the overall structural stability of the submersible centrifugal pump is fully considered. An axial suction and discharge structure is adopted, which makes the force more uniform. At the same time, axial dynamic and static sealing structures are set to ensure that leakage will not damage the bearings during use.

[0021] 2. Compared with traditional structures, the submersible centrifugal pump structure of this utility model has higher operational stability, longer service life, and advantages such as convenient on-site maintenance and small footprint.

[0022] 3. In this utility model, axial optimization design is carried out at the liquid inlet section, and a sliding bearing is added as the fulcrum of the shaft system span, which reduces the amount of flexural deformation during shaft system operation and ensures the smooth operation of the impeller.

[0023] 4. In this utility model, the inner rib plate of the liquid inlet not only supports the bearing seat, but also serves as a flow stabilizer plate for the suction chamber. When the material is in a turbulent state at the inlet, the stable flow velocity through the four rib plates ensures that the material entering the impeller is stable and smooth, without generating turbulence. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of a traditional submersible centrifugal pump.

[0026] Figure 2 This is a schematic diagram of a submersible centrifugal pump structure.

[0027] Figure 3 for Figure 2 A magnified view of a portion of point A in the middle.

[0028] Figure 4 This is a schematic diagram of the liquid inlet section in a submersible centrifugal pump.

[0029] Figure 5 This is a schematic diagram of the front section of a submersible centrifugal pump.

[0030] Figure 6 This is a cross-sectional view of the middle section of a submersible centrifugal pump structure.

[0031] Figure 7 This is a schematic diagram of the middle section of a submersible centrifugal pump.

[0032] Legend:

[0033] 1. Motor; 2. Motor frame; 21. Coupling; 3. Drive shaft; 31. Sliding bearing; 32. Shaft sleeve; 4. Discharge section; 41. Discharge port; 5. K-ring seal; 6. Auxiliary impeller; 7. Inlet section; 71. Front section; 711. Inlet port; 712. Bearing housing; 713. Rib plate; 72. Middle section; 721. Intermediate flow channel; 722. Arc-shaped blade; 73. Impeller; 74. Annular guide vane; 8. Intermediate connecting pipe. Detailed Implementation

[0034] 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 skilled in the art without creative effort are within the protection scope of the present utility model.

[0035] Example 1

[0036] Please see Figure 1-7This utility model provides a technical solution: a submersible centrifugal pump structure, comprising:

[0037] The drive section includes a motor 1 and a motor frame 2. A coupling 21 is installed inside the motor frame 2, and the motor 1 is connected to the drive shaft 3 through the coupling 21.

[0038] The liquid outlet section 4 is provided with a liquid outlet 41. The liquid outlet section 4 is fixedly installed on the lower side of the motor frame 2. A shaft seal structure is provided between the liquid outlet section 4 and the motor frame 2. The shaft seal structure includes a K-shaped sealing ring 5 and an auxiliary impeller 6 arranged sequentially from top to bottom along the axis of the drive shaft 3. The auxiliary impeller 6 is sleeved on the drive shaft 3.

[0039] The inlet section 7 is connected to the outlet section 4 via an intermediate connecting pipe 8. The inlet section 7 includes a front section 71, a middle section 72, an impeller 73, and an annular guide vane 74. The front section 71 has an inlet 711. The middle section 72 is mounted on the front section 71. The impeller 73 is located within the middle section 72 and is mounted on the drive shaft 3. The annular guide vane 74 is located on the outer side of the impeller 73. The middle section 72 is the component structure for mounting the annular guide vane 74, ensuring that the material smoothly exits from the annular guide vane 74 and enters the intermediate connecting pipe 8, before being discharged through the outlet section 4.

[0040] See appendix Figure 1 Traditional submersible centrifugal pumps have the pump body outlet on the side, and because they have a spiral volute, the water outlet direction can only be on the side. Under high flow and high pressure conditions, structural problems can lead to significant vibration and noise. At the same time, high pressure can cause some material to leak axially towards the bearing side.

[0041] See appendix Figure 2-3 This design fully considers the impact of high flow rates and high pressures on the overall structural stability of the submersible centrifugal pump. It adopts an axial suction and discharge structure, resulting in more even stress distribution. Simultaneously, it incorporates axial dynamic and static seals to ensure that leakage will not damage the bearings during operation. During pump operation, the auxiliary impeller provides a dynamic seal, while the K-ring seal 5 provides a static seal after shutdown, effectively eliminating the risk of axial leakage. Compared to traditional structures, the submersible centrifugal pump structure described in this application offers higher operational stability, extended service life, and advantages such as convenient on-site maintenance and smaller footprint.

[0042] Working Principle: The pressure chamber at the inlet of the submersible centrifugal pump is designed with guide vanes, similar to the annular structure of a multistage pump. This ensures relatively uniform force distribution, even under high inlet pressure. Water exiting the annular guide vane 74 enters the annular middle section 72, where the pressure is evenly distributed, allowing it to flow evenly into the intermediate pipe 8 and out axially. The axial seal employs a combination of dynamic and shutdown sealing, ensuring a leak-free seal during both operation and shutdown. During operation, the hydraulic design of the auxiliary impeller 6 generates a pressure head greater than that at the shaft seal. The impeller's rotation generates a pressure head that counteracts the axially transmitted pressure, achieving a dynamic sealing effect. When the submersible centrifugal pump stops, the K-ring seal provides a static seal. The combined effect of these two seals effectively guarantees the sealing performance.

[0043] Example 2

[0044] Based on the above embodiments, this embodiment further improves upon the following technical solution: the liquid inlet 711 is a conical structure that is narrow at the top and wide at the bottom.

[0045] The front section 71 of the liquid inlet section 7 is the suction chamber of the impeller 73, which adopts a conical suction structure design to quickly introduce materials.

[0046] Example 3

[0047] Based on the above embodiments, this embodiment further improves upon the following technical solution: a bearing seat 712 is provided inside the liquid inlet 711, the outer ring of the sliding bearing 31 is fixedly installed inside the bearing seat 712, the inner ring of the sliding bearing 31 is fitted onto the drive shaft 3, and a bushing 32 is provided between the inner ring of the sliding bearing 31 and the drive shaft 3.

[0048] Axial optimization design was carried out at the liquid inlet section 7, and a sliding bearing was added as the fulcrum of the shaft system span, which reduced the amount of flexural deformation during shaft system operation and ensured the smooth operation of impeller 73.

[0049] The sliding bearing 31 can be made of graphite, and the bushing 32 can be made of silicon carbide. The combination of soft and hard materials enhances the overall stability of the rotor components during operation.

[0050] In addition, four circumferentially arranged stiffening plates 713 are provided on the outer side of the bearing housing 712, and the stiffening plates 713 are fixedly installed on the inner wall of the liquid inlet 711.

[0051] The stiffeners 713 not only support the bearing housing 712, but also serve as flow stabilizers in the suction chamber. When the material is in a turbulent state at the inlet, the stable flow rate through the four stiffeners 713 ensures that the material entering the impeller 73 is smooth and stable, without generating turbulence.

[0052] Example 4

[0053] Based on the above embodiments, this embodiment further improves upon the following technical solution: a middle flow channel 721 connected to the middle connecting pipe 8 is provided on the middle section 72, and a number of circumferentially arranged arc-shaped blades 722 are provided in the middle flow channel 721.

[0054] After the material flows out from the annular guide vane 74, it flows into the intermediate pipe 8 through the intermediate flow channel 721 of the middle section 72. Several arc-shaped blades 722 are set in the intermediate flow channel 721, specifically as shown in the figure, with 7 blades. This takes into account both throughput and efficiency, and can increase the smoothness of the material entering the liquid outlet section 4, so as to avoid turbulence.

[0055] In addition, a stop structure is provided at the inner hole of the middle section 72 to increase the mouth ring and reduce leakage loss efficiency.

[0056] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A submersible centrifugal pump construction, characterized in that include: The drive section includes a motor and a motor frame, wherein a coupling is provided inside the motor frame, and the motor is connected to the drive shaft through the coupling. The liquid outlet section is provided with a liquid outlet. The liquid outlet section is fixedly installed on the lower side of the motor frame. A shaft seal structure is provided between the liquid outlet section and the motor frame. The shaft seal structure includes a K-shaped sealing ring and a secondary impeller arranged sequentially from top to bottom along the axis of the drive shaft. The secondary impeller is sleeved on the drive shaft. The liquid inlet section is connected to the liquid outlet section via an intermediate pipe. The liquid inlet section includes a front section, a middle section, an impeller, and an annular guide vane. The front section is provided with a liquid inlet. The middle section is installed on the front section. The impeller is disposed inside the middle section and is mounted on the drive shaft. An annular guide vane is provided on the outer side of the impeller.

2. A submersible centrifugal pump structure according to claim 1, characterized in that The liquid inlet has a conical structure that is narrow at the top and wide at the bottom.

3. The submersible centrifugal pump structure according to claim 1, characterized in that, A bearing housing is provided inside the liquid inlet. The outer ring of the sliding bearing is fixedly installed inside the bearing housing. The inner ring of the sliding bearing is fitted onto the drive shaft. A bushing is provided between the inner ring of the sliding bearing and the drive shaft.

4. The submersible centrifugal pump structure according to claim 3, characterized in that, The bearing housing is provided with several circumferentially arranged stiffening plates on its outer side, and the stiffening plates are fixedly installed on the inner wall of the liquid inlet.

5. The submersible centrifugal pump structure according to claim 4, characterized in that, The number of stiffening plates is 4.

6. The submersible centrifugal pump structure according to claim 1, characterized in that, The middle section is provided with an intermediate flow channel that communicates with the intermediate connecting pipe, and the intermediate flow channel is provided with a number of circumferentially arranged arc-shaped blades.

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