A double-shell low-noise high-speed centrifugal pump and its design method

Abstract

The present invention discloses a double-shell low-noise high-speed centrifugal pump and a design method thereof, which includes an outer shell component, a vibration-damping connecting component located inside the outer shell component, a pump body component, and a drive motor component and a pump shaft component located inside the pump body component; wherein the vibration-damping connecting component is the connecting portion between the outer shell component and the pump body component, and includes an inlet vibration-damping device, a normal-pressure static vibration-damping liquid, a superstructure vibration-damping assembly, and an outlet vibration-damping device; the inlet vibration-damping device connects the outer shell inlet and the pump inlet of the pump body component; the outlet vibration-damping device connects the outer shell outlet and the pump outlet of the pump body component; the superstructure vibration-damping assembly supports the pump body component and is connected to the outer shell component; the normal-pressure static vibration-damping liquid fills the gap between the outer shell component and the pump body component, wrapping the pump body component. The present invention suppresses the transmission of vibration from multiple paths through a double-shell structure and a vibration-damping connecting component between the shells.

Description

Technical Field

[0001] The present invention relates to the field of fluid machinery, and in particular to a double-shell low-noise high-speed centrifugal pump and a design method thereof. Background Art

[0002] Conventional centrifugal pumps have flanges connecting their inlet and outlet ports to external piping. Test results show that the vibration levels at the inlet and outlet flanges are high and difficult to isolate. Conventional centrifugal pumps are mounted on a base using vibration isolators. Structural vibrations of the pump casing are transmitted through the isolators and piping. When speeds exceed 20,000 rpm, the amplitude of vibration and noise increases significantly, making it even more difficult to control. For high-speed centrifugal pumps, more effective vibration control measures are required.

[0003] High-speed centrifugal pumps primarily derive their excitation from hydraulic and electromagnetic excitation. Even with optimized design of hydraulic components, drive motors, and pump structures, the characteristic frequencies of these excitation sources remain prominent. Installing vibration isolation structures in the vibration transmission path is a common method for further vibration reduction. These typically employ single-layer isolators, double-layer isolation with an intermediate mass, or floating rafts. However, these structures currently face challenges such as substandard isolation and bulky structures, and the potential for optimization of conventional isolation structures is limited.

[0004] Furthermore, as the speed and vibration level requirements for high-speed centrifugal pumps continue to increase, single excitation source control is no longer sufficient, and the optimized design of vibration reduction structures is imperative. Advances in superstructures and 3D printing technology are also providing new ideas for the design of vibration reduction structures. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention proposes a double-shell low-noise high-speed centrifugal pump and its design method. The double-shell structure provides more design optimization space for vibration reduction and noise reduction. The normal pressure static vibration-damping liquid distributed between the pump body and the outer shell plays a role in vibration reduction and vibration isolation. There is no rigid connection between the pump body and the outer shell. The vibration-damping structure between the outer shell inlet / outlet and the pump inlet / outlet reduces the propagation of pump inlet / outlet vibration to the outside. The super-structure vibration-damping assembly on the inner wall of the outer shell provides support and vibration isolation for the pump body. After the excitation of the excitation source is transmitted to the pump body, it is transmitted to the outer shell through the vibration-damping connection structure. The double-shell structure and vibration-damping design reduce the transmission of structural vibration and the propagation of radiated noise.

[0006] The specific technical solutions of the present invention are as follows:

[0007] A double-shell low-noise high-speed centrifugal pump, comprising an outer shell component, a vibration-damping connecting component located inside the outer shell component, a pump body component, and a drive motor component and a pump shaft component located inside the pump body component;

[0008] The outer shell component is a thick-walled shell-shaped sealing structure, comprising an outer shell upper cover, an outer shell cylinder and an outer shell lower cover which are sealed and connected in sequence; the outer shell lower cover is provided with an outer shell inlet, and the outer shell cylinder is provided with an outer shell outlet;

[0009] The vibration-damping connecting component is the connecting portion between the outer shell component and the pump body component, and includes an inlet vibration-damping device, a static vibration-damping liquid at normal pressure, a superstructure vibration-damping assembly, and an outlet vibration-damping device; the inlet vibration-damping device connects the outer shell inlet and the pump inlet of the pump body component; the outlet vibration-damping device connects the outer shell outlet and the pump outlet of the pump body component; the superstructure vibration-damping assembly supports the pump body component and is connected to the outer shell component; the static vibration-damping liquid at normal pressure fills the gap between the outer shell component and the pump body component, wrapping the pump body component;

[0010] The pump body component includes a pump upper cover, a pump casing, and a pump lower cover that are sealed and connected in sequence. The pump lower cover is provided with a pump inlet and a first-stage volute, the pump casing is provided with a pump outlet and a secondary volute, and the pump lower cover, pump casing, and pump upper cover are provided with a through flow passage;

[0011] The drive motor component is an integrated permanent magnet motor in the pump, including a drive motor stator, a winding and a drive motor rotor; the drive motor stator is assembled into one with the pump housing, and the winding is installed on the drive motor stator;

[0012] The pump shaft component includes a primary impeller, a secondary impeller and a pump shaft. The drive motor rotor is located in the middle of the pump shaft and integrated with the pump shaft. The primary impeller, the secondary impeller and the drive motor rotor are coaxial and share a common bearing.

[0013] Furthermore, the metastructure vibration damping assembly includes a fixed structure and a metamaterial sleeve structure, the fixed structure is embedded in the upper and lower end surfaces of the metamaterial sleeve structure; the fixed structure is respectively connected to the pump body component and the outer shell cylinder through fixing parts.

[0014] Furthermore, the inlet vibration damping device includes a strength support structure 1, an elastic structure 1 and a connection structure 1. The strength support structure 1 is a high-strength coarse metal strip, which is encapsulated in a circumferential array inside the elastic structure 1 to provide the structural strength requirements; the connection structure 1 adopts a semicircular butt joint design and is pressed onto the end flange of the elastic structure 1.

[0015] Furthermore, the outlet vibration damping device has the same structure as the inlet vibration damping device.

[0016] Furthermore, the pump shaft component also includes a shielding sleeve, an upper thrust bearing, an upper sliding bearing, a lower thrust bearing and a lower sliding bearing, and the shielding sleeve separates the drive motor stator and the drive motor rotor; the upper thrust bearing, the upper sliding bearing, the lower thrust bearing and the lower sliding bearing are used to support the entire pump shaft component.

[0017] Furthermore, the outer shell inlet and the pump inlet are located on the same side below the pump body component, and the outer shell outlet and the pump outlet are located on the same side of the side of the pump body component.

[0018] A design method for a double-shell low-noise high-speed centrifugal pump, the method comprising the following steps:

[0019] (1) Based on the given rated flow and head, the hydraulic components, pump housing and shaft structure are preliminarily determined through hydraulic design, and the motor electromagnetic design is synchronously carried out based on the speed and shaft power;

[0020] (2) Integrate the motor and pump body to improve structural rigidity;

[0021] (3) Through theoretical and numerical analysis, the fluid excitation characteristics, electromagnetic excitation characteristics, and rotor unbalance excitation characteristics of the hydraulic components are obtained;

[0022] (4) Analyze the spectrum characteristics of the excitation source, design the starting vibration isolation frequency of the vibration-damping connection component to isolate the excitation characteristic spectrum; and realize manufacturing through additive manufacturing technology;

[0023] (5) Design the structure of the outer shell components according to the pump body components and the vibration-damping connecting components to achieve full coverage of the pump body components, connection with the vibration-damping connecting components, and connection with external pipelines; design a certain cavity between the outer shell and the pump body to facilitate filling with normal pressure static vibration-damping liquid;

[0024] (6) Through modal analysis and vibration response analysis, combined with the frequency characteristics of the excitation source, the vibration-damping connection components and the outer shell components are optimized to reduce the excitation transmission and the vibration response at the machine foot, thereby completing the design.

[0025] The beneficial effects of the present invention are as follows:

[0026] (1) The double shell structure of the present invention provides a larger optimization space for suppressing the transmission of centrifugal pump vibration; there is no rigid connection between the pump body and the outer shell, both of which are vibration-damping connection components, and the motor rotor and the pump impeller share a common rotating shaft, and the motor and the pump share a common shell and upper and lower pump covers, so that the drive motor is integrated into the pump body, and the outer shell realizes the overall wrapping of the hydraulic transmission part and the power drive part, thereby suppressing the transmission of vibration from the pump body inlet and outlet, support position and multiple paths of the pump body, and reducing the propagation of flow-induced vibration in the pump inlet and outlet flow area to the external pipeline. In addition, the double shell structure design is filled with a liquid that can flow at normal pressure between the outer shell and the pump shell. The pump shell is wrapped by the liquid, making full use of viscous damping for vibration reduction, reducing the propagation of the vibration radiation noise of the pump shell; at the same time, the liquid between the outer shell and the pump body provides buoyancy for the pump body, reducing the force on the pump body vibration reduction support structure.

[0027] (2) In the design method of the present invention, the diversity of the outer shell structure design and the diversity of the vibration-damping connection structure design provide more optimization methods for vibration transmission suppression. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a structural diagram of a double-shell low-noise high-speed centrifugal pump.

[0029] Figure 2 This is a schematic diagram of the internal structure of the double-shell low-noise high-speed centrifugal pump of Example 1.

[0030] Figure 3 This is a schematic diagram of the internal structure of the double-shell low-noise high-speed centrifugal pump body.

[0031] Figure 4 This is a schematic diagram of the structure of the double-shell low-noise high-speed centrifugal pump shaft system.

[0032] Figure 5 Schematic diagram of the structure of the vibration-damping connection component.

[0033] In the figure, 1- outer shell component, 2- vibration damping connection component, 3- pump body component, 4- drive motor component, 5- pump shaft component; 101- outer shell inlet, 102- outer shell lower cover, 103- sealing ring 1, 104- outer shell cylinder, 105- outer shell outlet, 106- outer shell upper cover, 107- sealing ring 2, 201- inlet vibration damping device, 2011- strength support structure 1, 2012- connection structure 1, 2013- elastic structure 1, 202- normal pressure static vibration damping liquid, 203- super structure vibration damping assembly, 204- outlet vibration damping device, 2041- strength support structure 2, 2042- connection Structure 2, 2043-Elastic Structure 2, 301-Pump casing, 302-Pump outlet, 303-Secondary volute, 304-Pump upper cover, 305-Pump inlet, 306-First-stage volute, 307-Pump lower cover, 308-Flow channel, 401-Drive motor stator, 402-Winding, 403-Insulation glue, 404-Drive motor rotor, 501-First-stage impeller, 502-Secondary impeller, 503-Pump shaft, 504-First-stage impeller outlet, 505-Shielding sleeve, 506-Secondary impeller outlet, 507-Upper thrust bearing, 508-Upper sliding bearing, 509-Lower sliding bearing, 510-Lower thrust bearing. DETAILED DESCRIPTION

[0034] The present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments, and the purpose and effects of the present invention will become more apparent. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0035] As one of the implementation methods, Figure 1 As shown, the double-shell low-noise high-speed centrifugal pump includes an outer shell component 1, a vibration-damping connecting component 2 located inside the outer shell component 1, a pump body component 3, and a drive motor component 4 and a pump shaft component 5 located inside the pump body component 3.

[0036] like Figure 2 and Figure 3 As shown, the outer shell component 1 is a thick-walled, shell-shaped sealed structure, comprising an outer shell lower cover 102, an outer shell upper cover 106, and an outer shell cylinder 104. The outer shell inlet 101 is located on the outer shell lower cover 102, and the outer shell outlet 105 is located on the outer shell cylinder 104. The outer shell lower cover 102, the outer shell upper cover 106, and the outer shell cylinder 104 are respectively bolted together and sealed by sealing rings 103 and 107. The pump body component 3 is connected to the outer shell component 1 via a vibration-damping connecting component 2. The pump inlet 305 of the pump body component 3 is located at the bottom, and the pump outlet 302 is located to the side, and the pump inlet 305 is located on the same side as the outer shell inlet 101, and the pump outlet 302 is located on the same side as the outer shell outlet 105.

[0037] The vibration-damping connection component 2 includes an inlet vibration damping device 201, a static damping liquid at normal pressure 202, a superstructure vibration damping assembly 203, and an outlet vibration damping device 204. The outer shell inlet 101 is connected to the pump inlet 305 via the inlet vibration damping device 201, while the outer shell outlet 105 is connected to the pump outlet 302 via the outlet vibration damping device 204. The pump body component 3 is supported on the stepped surface of the outer shell cylinder 104 via the superstructure vibration damping assembly 203. The static damping liquid at normal pressure 202 fills the internal gap between the pump body component 3 and the outer shell cylinder 104, enveloping the pump body component 3 in the static damping liquid 202, thereby reducing vibrations by utilizing the viscous damping of the interstitial liquid.

[0038] like Figure 5 As shown, the inlet vibration damper 201 comprises a strength support structure 1 2011, an elastic structure 1 2013, and a connection structure 1 2012. The strength support structure 1 2011 consists of high-strength, coarse metal strips, arrayed circumferentially within the elastic structure 1 2013 to provide structural strength. The connection structure 1 2012 employs a semicircular butt-jointed design and is press-fitted onto the end flange of the elastic structure 1 2013. The connection structure 1 2012 is bolted to the inlet flange, securing and sealing the inlet vibration damper 201 to the pump inlet. The outlet vibration damper 204 has the same structure as the inlet vibration damper 201, comprising a strength support structure 2 2041, an elastic structure 2 2043, and a connection structure 2 2042. The strength support structure 2041 also consists of high-strength, coarse metal strips, arrayed circumferentially within the elastic structure 2043 to provide structural strength. The connection structure 2042 employs a semicircular butt-jointed design and is press-fitted onto the end edge of the elastic structure 2043. Outlet vibration damper 204 is connected to the pump outlet flange, securing and sealing the connection. To match the pump inlet and outlet flange diameters with the inlet and outlet pipe diameters of the casing, the inlet vibration damper 201 has a constant diameter internal cross-section, while the outlet vibration damper 204 has a variable diameter internal cross-section.

[0039] The inlet vibration damping device 201 reduces the propagation of vibration generated in the pump inlet flow area to the outside world, thereby reducing vibration in the water inlet pipe of the outer shell, and further reducing the propagation of vibration along the inlet pipe. The outlet vibration damping device 204 reduces the propagation of vibration generated in the outlet flow area to the outside world, thereby reducing vibration in the water outlet pipe of the outer shell, and further reducing the propagation of vibration along the outlet pipe.

[0040] The metastructure vibration damping assembly 203 is supported on the outer shell cylinder 104 and includes a fixed structure 2031 and a metamaterial sleeve structure 2032. The fixed structure 2031 is embedded in the upper and lower end surfaces of the metamaterial sleeve structure 2032. The design of the metamaterial sleeve structure 2032 achieves high stiffness and damping, thereby supporting and damping the pump unit. The fixed structure 2031 is connected to the pump body component 3 and the outer shell cylinder 104 by bolts. This design eliminates a rigid connection between the pump body component 3 and the outer shell cylinder 104. This allows flow-induced excitation at the inlet and outlet and vibration of the pump structure to be transmitted to the outer shell after passing through the vibration-damping connection structure, thereby reducing vibration transmission. At the same time, the application of metamaterial technology reduces the static deflection of the pump unit installation and provides high damping. The complex structure is fabricated through additive manufacturing technology, thereby providing high stiffness and high damping support for the pump body, alleviating the contradiction between high static stiffness and high vibration response.

[0041] like Figures 2-4 As shown, the drive motor component 4 and the pump shaft component 5 are integrated into the pump body component 3. The pump body component 3 includes a pump housing 301, a pump upper cover 304, and a pump lower cover 307. The pump upper cover 304, the pump housing 301, and the pump lower cover 307 are connected in sequence by bolts to form a sealing body. The pump inlet 305 and the first-stage volute 306 are integrated in the pump lower cover 307, the pump outlet 302 and the secondary volute 303 are integrated on the pump casing 301, and the flow channel 308 is opened and runs through the inside of the pump lower cover 307, the pump casing 301 and the pump upper cover 304. The incoming flow of the pump flows through the pump inlet 305 and the flow channel 308 inside the pump lower cover 307 into the first-stage impeller 501, and after completing the pressure increase and speed increase, flows into the first-stage volute 306 integrated in the pump lower cover 307 through the first-stage impeller outlet 504, passes through the flow channel 308 inside the pump casing 301, flows into the secondary impeller 502 through the flow channel 308 of the pump upper cover 304, and then flows out through the secondary volute 303 integrated on the pump casing 301 to the pump outlet 302 integrated on the pump casing 301.

[0042] like Figure 3 As shown, the drive motor component 4 is an integrated permanent magnet motor in the pump, including a drive motor stator 401, a winding 402, and a drive motor rotor 404. The drive motor stator 401 is assembled with the pump housing 301, the winding 402 is assembled into the groove of the drive motor stator 401, and the winding 402 is filled with insulating glue 403.

[0043] like Figure 4As shown, the pump shaft assembly 5 includes a primary impeller 501, a secondary impeller 502, a pump shaft 503, a shielding sleeve 505, an upper thrust bearing 507, an upper sliding bearing 508, a lower sliding bearing 509, and a lower thrust bearing 510. The drive motor rotor 404 is located in the middle of the pump shaft 503 and is integrated with the pump shaft 503. The shielding sleeve 505 is located between the two. The primary impeller 501 and the secondary impeller 502 are located at the upper and lower ends of the pump shaft 503, respectively. The drive motor rotor 404 and the pump shaft 503 are coaxial and share a common bearing. The primary impeller outlet 504 communicates with the primary volute 306, and the secondary impeller outlet 506 communicates with the secondary volute 303. The upper thrust bearing 507, the upper sliding bearing 508, the lower thrust bearing 510, and the lower sliding bearing 509 provide support for the entire pump shaft assembly 5.

[0044] The drive motor rotor 404 shares the pump shaft 503 with the primary impeller 501 and the secondary impeller 502. The motor and the pump share the casing and upper and lower pump covers, and the upper / lower mechanical seals are used to seal the conveying medium. This design allows the drive motor to be integrated inside the pump body, and the outer casing integrally wraps the hydraulic conveying part and the power drive part.

[0045] By utilizing the integrated design of the motor and the pump end, the pump body component 3 and the outer shell component 1 are both sealed structures. A certain gap space is designed between the two, and they are filled with a normal-pressure static vibration-damping liquid that can flow at normal pressure. This design further reduces the propagation of the pump body vibration radiation noise to the outside.

[0046] The present invention comprehensively analyzes and designs the outer shell, vibration-damping connection structure, and pump excitation, and controls the transmission of the excitation source to the outside. The design process is different from that of traditional centrifugal pumps. The design process of the double-shell low-noise high-speed centrifugal pump of the present invention is described as follows:

[0047] Step 1: Based on the rated flow and head required by the design, the hydraulic components, pump housing, and shafting structure are preliminarily determined through hydraulic design. The motor electromagnetic design is then performed synchronously based on the speed and shaft power.

[0048] Step 2: Use modal analysis to analyze and design the motor and pump body in an integrated manner to improve structural rigidity.

[0049] Step 3: Through theoretical and numerical calculation analysis, the fluid excitation characteristics, electromagnetic excitation characteristics and rotor imbalance excitation characteristics of the hydraulic components are obtained.

[0050] Step 4: Design the vibration-damping connecting component 2: According to the spectrum characteristics of the excitation source, the starting vibration isolation frequency of the vibration-damping connecting component 2 is designed to isolate the excitation characteristic spectrum, and according to the structure of the pump body component 3, the vibration-damping connecting component 2 is designed to support the pump body component 3 and realize the connection and sealing between the pump body component 3 and the outer shell component 1; and the vibration-damping connecting component 2 adopts multiple materials and metamaterial structure design to improve stiffness and increase damping, and is manufactured through additive manufacturing technology.

[0051] Step 5: Design the outer shell component 1 according to the structure of the pump body component 3 and the vibration-damping connecting component 2 to achieve full wrapping of the pump body component 3, connection with the vibration-damping connecting component 2, and connection with external pipelines, and design a certain cavity between the outer shell component 1 and the pump body component 3 to facilitate filling with room temperature static vibration-damping liquid.

[0052] Step 6: Optimize the structure of the vibration-damping connection component 2 and the outer shell component 1 through modal analysis and vibration response analysis to reduce the excitation transmission and the vibration response at the machine foot, thereby completing the design.

[0053] Those skilled in the art will understand that the foregoing descriptions are merely preferred embodiments of the invention and are not intended to limit the invention. Although the invention has been described in detail with reference to the foregoing examples, those skilled in the art will still be able to modify the technical solutions described in the foregoing examples or substitute equivalents for some of the technical features therein. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the invention shall be included within the scope of protection of the invention.

Claims

1. A double-shell low-noise high-speed centrifugal pump, characterized in that: It comprises an outer shell component (1), a vibration-damping connecting component (2) located inside the outer shell component (1), a pump body component (3), and a driving motor component (4) and a pump shaft component (5) located inside the pump body component (3); The outer shell component (1) is a thick-walled shell-shaped sealing structure, comprising an outer shell upper cover (106), an outer shell cylinder (104), and an outer shell lower cover (102) which are sealed and connected in sequence; an outer shell inlet (101) is provided on the outer shell lower cover (102), and an outer shell outlet (105) is provided on the outer shell cylinder (104); The vibration-damping connecting component (2) is a connecting portion between the outer shell component (1) and the pump body component (3), and comprises an inlet vibration-damping device (201), a normal-pressure static vibration-damping liquid (202), a superstructure vibration-damping assembly (203), and an outlet vibration-damping device (204); the inlet vibration-damping device (201) connects the outer shell inlet (101) and the pump inlet (305) of the pump body component (3); the outlet vibration-damping device (204) connects the outer shell outlet (105) and the pump outlet (302) of the pump body component (3); the superstructure vibration-damping assembly (203) supports the pump body component (3) and is connected to the outer shell component (1); the normal-pressure static vibration-damping liquid (202) fills the gap between the outer shell component (1) and the pump body component (3), and wraps the pump body component (3); The pump body component (3) includes a pump upper cover (304), a pump casing (301), and a pump lower cover (307) which are sealed and connected in sequence. The pump lower cover (307) is provided with a pump inlet (305) and a primary volute (306). The pump casing (301) is provided with a pump outlet (302) and a secondary volute (303). The pump lower cover (307), the pump casing (301), and the pump upper cover (304) are provided with a through-flow passage (308). The drive motor component (4) is an integrated permanent magnet motor in the pump, comprising a drive motor stator (401), a winding (402), and a drive motor rotor (404); the drive motor stator (401) is assembled into one piece with the pump housing (301), and the winding (402) is mounted on the drive motor stator (401); The pump shaft component (5) includes a primary impeller (501), a secondary impeller (502), and a pump shaft (503); the drive motor rotor (404) is located in the middle of the pump shaft (503) and is integrated with the pump shaft (503); the primary impeller (501), the secondary impeller (502), and the drive motor rotor (404) are coaxial and share a common bearing; The metastructure vibration damping assembly (203) comprises a fixed structure (2031) and a metamaterial sleeve structure (2032), wherein the fixed structure (2031) is embedded in the upper and lower end surfaces of the metamaterial sleeve structure (2032); the fixed structure (2031) is respectively connected to the pump body component (3) and the outer shell cylinder (104) via fixing members; The inlet vibration damping device (201) comprises a strength support structure (2011), an elastic structure (2013) and a connection structure (2012), wherein the strength support structure (2011) is a high-strength coarse metal strip, which is encapsulated in a circumferential array inside the elastic structure (2013) to provide structural strength requirements; the connection structure (2012) adopts a semicircular butt joint design and is press-fitted onto the end flange of the elastic structure (2013); The outlet vibration damping device (204) has the same structure as the inlet vibration damping device (201).

2. The double-shell low-noise high-speed centrifugal pump according to claim 1, characterized in that: The pump shaft component (5) further comprises a shielding sleeve (505), an upper thrust bearing (507), an upper sliding bearing (508), a lower thrust bearing (510) and a lower sliding bearing (509); the shielding sleeve (505) separates the drive motor stator (401) and the drive motor rotor (404); and the upper thrust bearing (507), the upper sliding bearing (508), the lower thrust bearing (510) and the lower sliding bearing (509) are used to support the entire pump shaft component (5).

3. The double-shell low-noise high-speed centrifugal pump according to claim 1, characterized in that: The outer shell inlet (101) and the pump inlet (305) are located on the same side below the pump body component (3), and the outer shell outlet (105) and the pump outlet (302) are located on the same side of the side of the pump body component (3).

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