A shielded condensate pump

Abstract

The present invention provides a shielded condensate pump, comprising a pump body and a shielded motor, wherein the shielded motor is mounted at one end of the pump body, a main shaft, an axial flow impeller, a first-stage impeller and a second-stage impeller are arranged in the pump body, the main shaft is rotatably mounted inside the pump body, the axial flow impeller, the first-stage impeller and the second-stage impeller are fixed on the main shaft in sequence from left to right, the shielded motor can drive the main shaft to rotate, the shielded motor comprises a motor housing, a stator and a rotor, the stator and the rotor are arranged in the motor housing, the rotor is mounted on the main shaft, the stator corresponds to the rotor, the left end of the motor housing is sealed and fixed to the end of the pump body, the right end of the motor housing is sealed through a rear bearing seat and a sealing ring, the right end of the main shaft is fixed to the rear bearing seat through a bearing sleeve, the right end of the rear bearing seat is also connected to a circulating cooling pipe, and the other end of the circulating cooling pipe is butted with the rear bearing seat. The advantages of the present invention are: low vibration and noise, small size and light weight, and completely no leakage.

Description

Technical Field

[0001] The invention relates to the field of condensate pumps, and in particular to a shielded condensate pump. Background Art

[0002] At present, the condensate pump adopts the ordinary centrifugal pump type, with one or two centrifugal impellers working to transport the condensate to the next level of equipment. The output shaft is connected to the outside world with a mechanical seal to prevent the medium in the pump from leaking into the outside environment. Due to the installation position restrictions of the condensate pump, it requires a very low cavitation margin to work, and is driven by a low-speed six-pole or even eight-pole motor. Such condensate pumps have many shortcomings that need to be improved: heavy weight, high vibration and noise during operation, and wear of the mechanical seal that easily causes medium leakage. Summary of the invention

[0003] The object of the present invention is to provide a shielded condensate pump which has low vibration and noise, small size, light weight and no leakage.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] A shielded condensate pump comprises a pump body and a shielded motor, wherein the shielded motor is mounted at one end of the pump body, wherein a main shaft, an axial-flow impeller, a first-stage impeller and a second-stage impeller are arranged in the pump body, wherein the main shaft is rotatably mounted in the pump body through a first sliding bearing, a second sliding bearing and a third sliding bearing respectively, wherein the axial-flow impeller, the first-stage impeller and the second-stage impeller are fixed on the main shaft in sequence from left to right, wherein the axial-flow impeller corresponds to a medium inlet of the pump body and can convey the medium from the medium inlet to the first-stage impeller, wherein the first-stage impeller can convey the medium to the second-stage impeller, and wherein the second-stage impeller can output the medium from the outlet of the pump body, wherein the shielded motor can drive the main shaft to rotate, wherein the shielded The motor includes a motor housing, a stator and a rotor, wherein the stator and the rotor are arranged in the motor housing, and the rotor is mounted on the main shaft, the stator corresponds to the rotor, the left end of the motor housing is sealed and fixed to the end of the pump body, and the right end of the motor housing is sealed by a rear bearing seat and a sealing ring, the right end of the main shaft extends to the right to the rear bearing seat, and is fixed to the rear bearing seat by a bearing sleeve, and the right end of the rear bearing seat is also connected to a circulating cooling pipe, one end of the circulating cooling pipe is connected to the pump body outlet, and the other end of the circulating cooling pipe is connected to the rear bearing seat, the medium can enter the circulating cooling pipe from the pump body outlet, and enter between the stator and the rotor from the rear bearing seat, and finally can flow out from the pump body outlet.

[0006] Further, the first sliding bearing is installed on the main shaft through a first sleeve, the second sliding bearing is installed on the main shaft through a second sleeve, and the third sliding bearing is installed on the main shaft through a third sleeve.

[0007] Furthermore, the left end cover of the pump body is provided with an end cover, the end cover is fixed to the pump body by screws, and the left end of the main shaft is provided with a locking nut.

[0008] Furthermore, the inner surface of the stator and the outer surface of the rotor are both wrapped with a metal sleeve.

[0009] Furthermore, the axial flow impeller includes a hub, a plurality of long blades and a plurality of short blades, the plurality of long blades are spirally and evenly arranged around the outer circumference of the hub along the axial direction of the hub, the plurality of short blades are arranged between every two long blades, and the short blades are arranged close to the right end of the main shaft.

[0010] Furthermore, the first sliding bearing includes a bearing body, the surface of the bearing body in contact with the main shaft is a bearing surface, four first lubrication grooves arranged in a circular array are arranged along the axial direction of the bearing surface, a second lubrication groove is arranged on one end surface of the bearing body corresponding to the first lubrication groove, the first lubrication groove is connected to the second lubrication groove, and a spiral groove is arranged on the bearing surface.

[0011] The beneficial effects of the present invention are:

[0012] The pump body of the present invention is made into an axially open type, and an axial flow impeller is added to the medium inlet end in front of the first-stage impeller to increase the pressure at the first-stage impeller inlet, thereby reducing the cavitation margin at the first-stage impeller inlet. In addition, the main shaft of the present application is supported by a sliding bearing, and the sliding bearing is lubricated by the medium, thereby greatly reducing the mechanical noise and vibration generated between the sliding bearing and the main shaft; and the motor of the present invention adopts a shielded motor, without the fan and rolling bearing of an ordinary motor, further controlling the noise and vibration generated by the motor. Moreover, the stator of the shielded motor is sealed with the pump body by a sealing gasket, and the rotor of the motor is installed on the main shaft, so the rotor of the motor and the axial flow impeller, the first-stage impeller and the second-stage impeller share the same main shaft, and the main shaft has no dynamic seal with the outside world, and there is no friction damage, which can achieve the purpose of safety, reliability and no leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a cross-sectional view of the present invention;

[0014] Figure 2 is a side view of the sliding bearing of the present invention;

[0015] Figure 3 yes Figure 2 A cross-sectional view at AA;

[0016] Figure 4 It is a structural schematic diagram of the axial flow impeller of the present invention. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings:

[0018] like Figures 1 to 4 As shown, a shielded condensate pump includes a pump body 1 and a shielded motor, wherein the shielded motor is installed at one end of the pump body 1, and the pump body 1 and the shielded motor are integrated, wherein the motor housing 11 is fixedly connected to the pump body 1, and a closed cavity is formed together through a sealing gasket 15 and a rear bearing seat 14. The rotor 13 and the rotating parts such as the axial flow impeller 3, the first-stage impeller 4 and the second-stage impeller 5 share a main shaft 2, and all are operated in the medium in the sealed cavity of the pump body 1. The inner wall of the stator 12 and the outer surface of the rotor 13 are both covered with a metal sleeve to isolate the medium from the iron core of the stator 12 and the iron core of the rotor 13. After the shielded motor is powered on, the stator 12 generates magnetic force to drive the rotor 13 to rotate, and the rotor 13 drives the axial flow impeller 3, the first-stage impeller 4 and the second-stage impeller 5 on the same main shaft 2 to operate, thereby doing work on the medium. The medium enters from the medium inlet, enters the first-stage impeller 4 after being pressurized by the axial flow impeller 3, enters the second-stage impeller 5 through the channel in the pump body 1 after being pressurized by the first-stage impeller 4, and is then discharged from the pump body outlet.

[0019] The pump body 1 includes an upper pump body and a lower pump body. A main shaft 2, an axial flow impeller 3, a first-stage impeller 4 and a second-stage impeller 5 are arranged in the pump body 1. The main shaft 2 is rotatably installed in the pump body 1 through a first sliding bearing 6, a second sliding bearing 7 and a third sliding bearing 8 respectively. The axial flow impeller 3, the first-stage impeller 4 and the second-stage impeller 5 are fixed on the main shaft 2 from left to right. The axial flow impeller 3 corresponds to the medium inlet 9 of the pump body 1, and can transport the medium from the medium inlet 9 to the first-stage impeller 4. The first-stage impeller 4 can transport the medium to the second-stage impeller 5. The second-stage impeller 5 can output the medium from the outlet 21 of the pump body. The shielded motor can drive the main shaft 2 to rotate. The shielded motor includes a motor housing 11, a stator 12 and a rotor 13. The stator 12 and The rotor 13 is arranged in the motor housing 11, and the rotor 13 is installed on the main shaft 2. The stator 12 corresponds to the rotor 13. The left end of the motor housing 11 is sealed and fixed to the end of the pump body 1, and the right end of the motor housing 11 is sealed by the rear bearing seat 14 and the sealing ring 15. The right end of the main shaft 2 extends to the right to the rear bearing seat 14 and is fixed to the bearing of the rear bearing seat 14 through the bearing sleeve 16. The right end of the rear bearing seat 14 is also connected to a circulating cooling pipe 17, one end of the circulating cooling pipe 17 is connected to the pump body outlet 21, and the other end of the circulating cooling pipe 17 is connected to the rear bearing seat 14. The medium can enter the circulating cooling pipe 17 from the pump body outlet, and enter between the stator 12 and the rotor 13 from the rear bearing seat 14, and finally can flow out from the pump body outlet 21.

[0020] In this embodiment, the first sliding bearing 6 is installed on the main shaft 2 through the first sleeve 21 , the second sliding bearing 7 is installed on the main shaft 2 through the second sleeve 22 , and the third sliding bearing 8 is installed on the main shaft 3 through the third sleeve 23 .

[0021] In this embodiment, the left end cover of the pump body 1 is provided with an end cover 18 , and the end cover 18 is fixed to the pump body 1 by screws 19 , and a locking nut 20 is provided at the left end of the main shaft 2 .

[0022] In this embodiment, the inner surface of the stator 12 and the outer surface of the rotor 13 are both wrapped with a metal sleeve.

[0023] In this embodiment, the axial flow impeller 3 includes a hub 31, a plurality of long blades 32 and a plurality of short blades 33. The plurality of long blades 32 are spirally and evenly arranged around the outer circumference of the hub 31 along the axial direction of the hub 31, and the plurality of short blades 33 are arranged between every two long blades 32, and the short blades 32 are arranged close to the right end of the main shaft 2.

[0024] The axial flow impeller 3 in this embodiment includes long blades 32 and short blades 33. The drainage effect of the short blades 33 is utilized so that the mainstream can flow around the long blades 32 with minimal impact after passing through the short blades 33. At the same time, the fluid passes through the gaps so that it can withstand the adverse pressure gradient of the fluid, thereby delaying or even preventing the separation of the boundary layer.

[0025] The first sliding bearing 6, the second sliding bearing 7 and the third sliding bearing 8 have the same structure. The structure of the first sliding bearing 6 is now described. The first sliding bearing 6 includes a bearing body 61. The surface of the bearing body 61 in contact with the main shaft 2 is a bearing surface 62. Four first lubrication grooves 63 arranged in a circular array are arranged along the axial direction of the bearing surface 62. A second lubrication groove 64 is arranged on one end surface of the bearing body 61 corresponding to the first lubrication groove 63. The first lubrication groove 63 is connected to the second lubrication groove 64. A spiral groove 65 is also arranged on the bearing surface 62.

[0026] In a preferred embodiment, a reticulated oil groove 66 is further provided on the bearing surface 62 to avoid a lubrication blind spot and effectively prolong the lubrication time of the medium on the bearing surface 62, so that the sliding bearing 6 has higher pressure resistance, wear resistance and excellent lubrication performance.

[0027] The pump body 1 of the present invention is made into an axially open type, and an axial flow impeller 3 is added at the medium inlet 9 end in front of the first-stage impeller 4 to increase the pressure at the inlet of the first-stage impeller 4, thereby reducing the cavitation margin at the inlet of the first-stage impeller 4. In addition, the main shaft 2 of the present application is supported by a sliding bearing, and the sliding bearing is lubricated by the medium, thereby greatly reducing the mechanical noise and vibration generated between the sliding bearing and the main shaft 2; and the motor of the present invention adopts a shielded motor, without the fan and rolling bearing of an ordinary motor, further controlling the noise and vibration generated by the motor. Moreover, the stator 12 of the shielded motor is sealed with the pump body 1 by a sealing ring, and the rotor 13 of the motor is installed on the main shaft 2, so the rotor 13 of the motor and the axial flow impeller 3, the first-stage impeller 4 and the second-stage impeller 5 share the same main shaft 2, and the main shaft 2 has no dynamic seal with the outside world, and there is no friction damage, which can achieve the purpose of safety, reliability and no leakage.

[0028] The above description does not limit the technical scope of the present invention in any way. Any modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A shielded condensate pump, characterized in that: The pump comprises a pump body and a shielded motor. The shielded motor is installed at one end of the pump body. A main shaft, an axial-flow impeller, a first-stage impeller and a second-stage impeller are arranged in the pump body. The main shaft is rotatably installed in the pump body through a first sliding bearing, a second sliding bearing and a third sliding bearing respectively. The axial-flow impeller, the first-stage impeller and the second-stage impeller are fixed on the main shaft from left to right in sequence. The axial-flow impeller corresponds to the medium inlet of the pump body and can transport the medium from the medium inlet to the first-stage impeller. The first-stage impeller can transport the medium to the second-stage impeller. The second-stage impeller can transport the medium from the medium inlet to the second-stage impeller. The outlet of the pump body outputs, and the shielded motor can drive the main shaft to rotate. The shielded motor includes a motor housing, a stator and a rotor. The stator and the rotor are arranged in the motor housing, and the rotor is installed on the main shaft. The stator corresponds to the rotor. The left end of the motor housing is sealed and fixed to the end of the pump body. The right end of the motor housing is sealed through the rear bearing seat and the sealing ring. The right end of the main shaft extends to the right to the rear bearing seat and is fixed to the rear bearing seat through the bearing sleeve. The right end of the rear bearing seat is also connected to a circulating cooling pipe, and one end of the circulating cooling pipe is connected to the pump body outlet. The other end is butt-jointed with the rear bearing seat, and the medium can enter the circulating cooling pipe from the pump body outlet, and enter between the stator and the rotor from the rear bearing seat, and finally flow out from the pump body outlet; the first sliding bearing is installed on the main shaft through the first sleeve, the second sliding bearing is installed on the main shaft through the second sleeve, and the third sliding bearing is installed on the main shaft through the third sleeve; the left end cover of the pump body is provided with an end cover, which is fixed to the pump body by screws, and a locking nut is provided at the left end of the main shaft; the inner surface of the stator and the outer surface of the rotor are both wrapped with a metal sleeve; the axial flow impeller is wrapped The first sliding bearing comprises a bearing body, a plurality of long blades and a plurality of short blades, wherein the plurality of long blades are spirally and evenly arranged around the outer circumference of the hub along the axial direction of the hub, and the plurality of short blades are arranged between every two long blades, and the short blades are arranged close to the right end of the main shaft; the first sliding bearing comprises a bearing body, and the surface of the bearing body in contact with the main shaft is a bearing surface, and four first lubrication grooves arranged in a circular array are arranged along the axial direction of the bearing surface, and a second lubrication groove is arranged on one end surface of the bearing body corresponding to the first lubrication groove, and the first lubrication groove is connected with the second lubrication groove, and a spiral groove is arranged on the bearing surface.

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