Energy-saving electric centrifugal pump sealing device and centrifugal pump

Abstract

The invention relates to the technical field of electric centrifugal pumps, and particularly discloses an energy-saving electric centrifugal pump sealing device and a centrifugal pump, the energy-saving electric centrifugal pump sealing device comprises a sealing cover, a motor and a rotating shaft, a static ring, a moving ring and an impeller are sequentially arranged on the rotating shaft, a liquid storage cover is arranged between the impeller and the sealing cover, and slots are formed in the liquid storage cover in a circumferential array mode; the sealing cover is fixedly communicated with a flushing pipe, and the flushing pipe conveys liquid to the liquid storage cover. According to the centrifugal pump, the static ring and the movable ring are covered through the liquid storage cover, when the centrifugal pump operates, the liquid storage cover is filled with liquid through the flushing pipe, the static ring and the movable ring are continuously lubricated, the liquid in the liquid storage cover can also enter the centrifugal pump along with rotation of the impeller, and the condition of medium cutoff in the operation process is prevented; and the impeller stops rotating, and the liquid in the liquid storage cover is retained, so that lubrication is provided for a short period of time during next starting, and dry burning is prevented.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric centrifugal pumps, in particular to an energy-saving electric centrifugal pump sealing device and centrifugal pump. BACKGROUND

[0002] It is known that an electric centrifugal pump is used to suck water by rotating an impeller in a volute through a motor to form a negative pressure area. When conveying general clean medium (water, oil), the sealing device of centrifugal force often adopts a single-end-face sealing method to seal by a set of dynamic and static rings, which is simple in structure.

[0003] For example, an invention patent with the application publication number CN119308883A and the application publication date of January 14, 2025, and the name of “a mouth ring sealing device of a centrifugal pump and a centrifugal pump” includes a dynamic ring and a static ring arranged between the mouth ring and the front cover of the impeller. The distance between the adjacent two groups of static ring teeth is Bc, and the distance between the inner circumferential surface of the static ring and the outer circumferential surface of the dynamic ring is Ht. The cross section of the dynamic ring tooth is in the shape of “dry”, including a radial ring tooth extending in the radial direction, a first axial ring tooth perpendicular to the radial ring tooth and parallel to each other, and a second axial ring tooth. The distance Hb between the first axial ring tooth and the second axial ring tooth is 0.05Ht-0.35Ht. The distance Ha between the first axial ring tooth and the outer circumferential surface of the dynamic ring is 0.05Ht-0.35Ht. The tooth thickness Ba of the radial ring tooth in the axial direction is 0.1Bc-0.4Bc. The tooth width Hv of the first axial ring tooth and the second axial ring tooth in the radial direction is 0.1Ht-0.2Ht. The distance Cs between the first axial ring tooth, the second axial ring tooth and the adjacent two sides of the static ring tooth is 0.1Bc-0.25Bc. The present application adjusts the structure of the dynamic ring tooth to increase the eddy current loss inside the sealing cavity, thereby greatly reducing the leakage of the fluid at the mouth ring under high pressure working condition.

[0004] The deficiency of the prior art is that when the centrifugal pump is running, a very thin liquid film is formed between the dynamic ring and the static ring to achieve sealing, and when the medium flow is interrupted during the operation of the centrifugal pump (the pump is started without filling liquid, and the liquid is pumped without supplying liquid), the liquid is lacking between the dynamic ring and the static ring, which is easy to cause dry burning of the end face and affect. SUMMARY

[0005] The purpose of the present application is to provide an energy-saving electric centrifugal pump sealing device and centrifugal pump to solve the above-mentioned deficiencies in the prior art.

[0006] In order to achieve the above-mentioned objectives, the present invention provides the following technical solutions: an energy-saving electric centrifugal pump sealing device and a centrifugal pump, comprising a sealing cover, a motor and a rotating shaft, wherein a static ring, a dynamic ring and an impeller are sequentially arranged on the rotating shaft, a liquid storage cover is arranged between the impeller and the sealing cover, and slots are opened in a circumferential array on the liquid storage cover, and a flushing pipe is fixedly connected to the sealing cover, and the flushing pipe infuses liquid into the liquid storage cover.

[0007] As a further description of the above technical solution: elastic sheets that fit the liquid storage cover are arranged in a circumferential array on the impeller, and the elastic sheets move away from the liquid storage cover as the impeller rotates to open the slot.

[0008] As a further description of the above technical solution: a retaining cover is fixedly provided on the rotating shaft, and a first spring is provided between the moving ring and the retaining cover.

[0009] As a further description of the above technical solution: it also includes a limiting component, which includes a limiting head slidably connected to the sealing cover in a circular array, and the limiting head is driven to move into the liquid storage cover to fit the dynamic ring.

[0010] As a further description of the above technical solution: it also includes a flushing mechanism, which includes a reflux chamber arranged on the sealing cover and connected to the liquid storage cover, and the flushing pipe is fixedly connected to the reflux chamber.

[0011] As a further description of the above technical solution: a partition is slidably connected in the reflux chamber, and the partition is provided with a hollow limiting head in a circular array. The partition moves with the liquid outflow of the flushing pipe to enable the limiting head to infuse liquid into the liquid storage cover.

[0012] As a further description of the above technical solution: a liquid outlet is provided at the end of the outer side wall of the limiting head, and a guide hole for the limiting head to slide is provided on the sealing cover.

[0013] An energy-saving electric centrifugal pump also includes a pump casing for carrying the impeller, the sealing cover is arranged on the pump casing, the pump casing includes a water inlet and a water outlet, and the flushing pipe inlet is arranged at the water outlet.

[0014] As a further description of the above technical solution: the impeller is provided with a pressure relief valve facing the liquid storage cover, and the pressure relief valve faces the water inlet.

[0015] As a further description of the above technical solution: an end face bracket is fixedly connected to one side of the pump housing, and a bearing for supporting the rotating shaft is provided in the end face bracket.

[0016] In the above technical solution, the present invention provides an energy-saving electric centrifugal pump sealing device and a centrifugal pump, which cover the static ring and the dynamic ring through a liquid storage cover, and when the centrifugal pump is running, the liquid storage cover is filled with liquid through a flushing pipe to continuously lubricate the static ring and the dynamic ring. The liquid in the liquid storage cover will also enter the centrifugal pump as the impeller rotates, preventing the medium from being interrupted during operation. When the centrifugal pump is turned off, the impeller stops rotating, and the liquid in the liquid storage cover is retained to provide lubrication for a short period of time when it is started next time to prevent dry burning. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments described in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0018] Figure 1 A schematic diagram of the overall structure provided by an embodiment of the present invention;

[0019] Figure 2 A schematic diagram of the overall structure from another angle provided by an embodiment of the present invention;

[0020] Figure 3 A schematic diagram of the exploded structure of the impeller and the rotating shaft provided in an embodiment of the present invention;

[0021] Figure 4 A schematic diagram of an exploded structure of a pump casing provided by an embodiment of the present invention;

[0022] Figure 5 A schematic structural diagram of an impeller provided in an embodiment of the present invention;

[0023] Figure 6 A schematic cross-sectional view of the overall structure provided by an embodiment of the present invention;

[0024] Figure 7 for Figure 6 Enlarged schematic diagram at point C in the middle;

[0025] Figure 8 An exploded schematic diagram of the structure of the flushing mechanism provided by an embodiment of the present invention;

[0026] Figure 9 for Figure 8 A in the middle is an enlarged schematic diagram;

[0027] Figure 10 for Figure 8 Enlarged schematic diagram of point B in the middle.

[0028] Description of reference numerals:

[0029] 1, dynamic ring; 11, sliding frame; 111, first spring; 12, retaining cover; 121, fixed screw hole; 2, static ring; 3, liquid storage cover; 31, slot; 4, flushing mechanism; 40, backflow chamber; 41, flushing pipe; 42, limiting head; 43, partition; 431, second spring; 432, perforation; 5, pump shell; 50, end face support; 501, bearing; 51, sealing cover; 511, anastomosis surface; 512, guide hole; 52, impeller; 521, pressure relief valve; 523, elastic sheet; 6, motor; 61, rotating shaft; 611, fixed head; 62, shaft coupling. DETAILED DESCRIPTION

[0030] In order to make the technical personnel in the art better understand the technical solutions of the present application, the present application will be further described in detail below in conjunction with the drawings.

[0031] Example one

[0032] Please refer to Figures 1-10 The present application provides a technical solution: an energy-saving electric centrifugal pump sealing device, comprising a sealing cover 51, a motor 6 and a rotating shaft 61, the rotating shaft 61 is sequentially provided with a static ring 2, a dynamic ring 1 and an impeller 52, the impeller 52 and the sealing cover 51 are provided with a liquid storage cover 3, the liquid storage cover 3 is provided with a slot 31 in a circumferential array, the sealing cover 51 is fixedly connected with a flushing pipe 41, and the flushing pipe 41 outputs liquid to the liquid storage cover 3.

[0033] Specifically, the static ring 2 is arranged in the hole provided in the center of the sealing cover 51, and at least one rubber sealing ring is arranged between the static ring 2 and the sealing cover 51, the static ring 2 and the rotating shaft 61 are gap-fitted, the rotating shaft 61 can rotate, the liquid storage cover 3 is fixedly connected to the sealing cover 51 by screws, there is a gap between the liquid storage cover 3 and the impeller 52, when the impeller 52 rotates, liquid can be brought out through the gap, the dynamic ring 1 is always attached to the static ring 2 and is rubbed when the impeller 52 rotates, forming a thin liquid surface to seal, the liquid medium output by the flushing pipe 41 is the same as the medium pumped by the centrifugal pump, the flushing pipe 41 is directed to the attachment of the static ring 2 and the dynamic ring 1 to flush the static ring 2 and the dynamic ring 1 through the flushing pipe 41, and when the dynamic ring 1 wears, the accumulated debris is timely removed to ensure the sealing capacity of the device, and the flushing pipe 41 pours liquid into the liquid storage cover 3, when the rotating shaft 61 rotates, the dynamic ring 1 in the liquid storage cover 3 rotates with it, agitating the liquid storage cover 3 to rotate along the central axis of the rotating shaft 61, generating centrifugal force to throw the liquid storage cover 3 out of the slot 31, accelerating the replacement speed of the liquid in the liquid storage cover 3, reducing heat accumulation, and timely cleaning the impurities generated when the dynamic ring 1 and the static ring 2 rub.

[0034] Preferably, the motor 6 is a two-level energy-efficient general motor in line with the GB18613-2012 standard, and has certain energy-saving effect. The rotating shaft 61 is threadedly connected with a fixing head 611, and the fixing head 611 is used for fixedly connecting the impeller 52 to the rotating shaft 61.

[0035] In still another embodiment of the present application, the impeller 52 is provided with a plurality of elastic sheets 523 arranged in a circumferential array and abutting against the liquid storage cover 3, and the elastic sheets 523 rotate away from the liquid storage cover 3 along with the impeller 52 to open the gap 31.

[0036] Specifically, the elastic sheets 523 are arranged on the side of the impeller 52 facing the sealing cover 51, and the elastic sheets 523 are provided at the ends with counterweights made of stainless steel. When the impeller 52 rotates, the counterweights are pulled away from the liquid storage cover 3 by centrifugal force, and thus the gap 31 is opened during the operation of the centrifugal pump. When the centrifugal pump stops operating, the elastic sheets 523 rebound to shield the gap between the gap 31 and the liquid storage cover 3 and the impeller 52, and the liquid in the liquid storage cover 3 is retained by the tension of the liquid, so that the dynamic ring 1 and the static ring 2 are lubricated in time when the centrifugal pump is started next time.

[0037] Preferably, the rotating shaft 61 is fixedly provided with a retaining cover 12, the retaining cover 12 is provided with a fixed screw hole 121, and the retaining cover 12 is fixed to the rotating shaft 61 by a screw. The retaining cover 12 is slidably connected with a sliding frame 11 for fixing the dynamic ring 1, and the first spring 111 is arranged between the dynamic ring 1 and the sliding frame 11 and pushes against the dynamic ring 1, so that the dynamic ring 1 always abuts against the static ring 2.

[0038] In still another embodiment of the present application, the limiting assembly further comprises a plurality of limiting heads 42 slidably connected to the sealing cover 51 in a circumferential array, and the limiting heads 42 are driven to move into the liquid storage cover 3 to abut against the dynamic ring 1.

[0039] Specifically, when the impeller 52 shakes due to excessive power during operation, the dynamic ring 1 and the static ring 2 are easily misaligned, and after a period of use, the unilateral wear of the dynamic ring 1 is too large, which causes the sealing ability to decrease. The limiting heads 42 are slidably connected to the sealing cover 51, and when the centrifugal pump operates, the limiting heads 42 extend into the liquid storage cover 3 and abut against the outside of the dynamic ring 1, so as to limit the dynamic ring 1 and the static ring 2 to be coaxial and reduce the misalignment range, thereby maintaining the sealing ability of the dynamic ring 1 and the static ring 2.

[0040] In still another embodiment of the present application, the flushing mechanism 4 further comprises a backflow cabin 40 arranged on the sealing cover 51 and communicating with the liquid storage cover 3, and a flushing pipe 41 fixedly connected to the backflow cabin 40.

[0041] Specifically, a fitting surface 511 is provided on the sealing cover 51, and the reflux chamber 40 is fixedly connected to the fitting surface 511 by fasteners, and the flushing pipe 41 is fixedly connected to the reflux chamber 40. When the flushing pipe 41 transports liquid as the centrifugal pump runs, the reflux chamber 40 will be filled first, and the liquid in the reflux chamber 40 will be poured into the liquid storage cover 3. When the centrifugal pump is turned off, the connection between the reflux chamber 40 and the liquid storage cover 3 is cut off, and liquid is accumulated in the reflux chamber 40. When the centrifugal pump is restarted, the reflux chamber 40 and the liquid storage cover 3 are connected again, and liquid continues to enter the liquid storage cover 3, thereby extending the time for preventing dry burning, so that the user can detect whether the pump filling operation is not performed when the centrifugal pump is restarted.

[0042] Preferably, a partition 43 is slidably connected to the reflux chamber 40, and the partition 43 is provided with a hollow limiting head 42 in a circumferential array. A second spring 431 is provided between the partition 43 and the reflux chamber 40. A perforation 432 is provided on the partition 43 for the flow of liquid in the two areas separated by the partition 43. The auxiliary partition 43 moves the flushing pipe 41 provided at one end of the reflux chamber 40, such as Figure 7 As shown, when water enters the flushing pipe 41, the pressure in the area of ​​the partition 43 toward the flushing pipe 41 increases, and the partition 43 overcomes the pulling force of the second spring 431 to move, thereby driving the limiting head 42 to move toward the liquid storage cover 3 while infusing liquid.

[0043] Preferably, a liquid outlet is provided at the end of the outer wall of the limiting head 42, and a guide hole 512 is provided on the sealing cover 51 for the limiting head 42 to slide. When the partition 43 moves, the limiting head 42 slides out along the guide hole 512, thereby restricting the dynamic ring 1 while guiding the liquid to flow out along the liquid outlet to flush the joint between the dynamic ring 1 and the static ring 2.

[0044] Example 2

[0045] See also Figures 1-10 An embodiment of the present invention provides a technical solution: an energy-saving electric centrifugal pump, which also includes a pump casing 5 for carrying an impeller 52, a sealing cover 51 is arranged on the pump casing 5, the pump casing 5 includes a water inlet and a water outlet, and the inlet of the flushing pipe 41 is arranged at the water outlet.

[0046] Specifically, the inlet of the flushing pipe 41 is located at the water outlet of the pump casing 5 and is inclined toward the impeller 52 at an angle of 10° to 45°. The flushing mechanism 4 relies on the water circulation of the pump casing 5 for flushing, which reduces external connected equipment, facilitates installation, and reduces costs.

[0047] In another embodiment provided by the present invention, a pressure relief valve 521 facing the liquid storage cover 3 is provided on the impeller 52, and the pressure relief valve 521 faces the water inlet.

[0048] Specifically, the pressure relief valve 521 is located in the cover range of the liquid accumulator cover 3. When the power of the centrifugal pump increases, the pressure increases, and the liquid entering the flushing pipe 41 increases, the pressure increases, and then the pressure in the liquid accumulator cover 3 increases. At this time, the pressure relief valve 521 is opened, and the liquid that cannot be discharged from the liquid accumulator cover 3 is discharged from the pressure relief valve 521 to the center of the impeller 52, so as to reduce the negative pressure at the center of the impeller 52, thereby reducing the cavitation of the impeller 52.

[0049] Preferably, the pump shell 5 is fixedly connected with an end face support 50 on one side, the end face support 50 is provided with a bearing 501 for supporting the rotating shaft 61, the support capacity of the rotating shaft 61 is increased, and the motor 6 is connected to the end face support 50 through fasteners.

[0050] When the centrifugal pump is started, the motor 6 drives the rotating shaft 61 to rotate and drives the impeller 52 to rotate, water is pumped from the water inlet of the pump shell 5 and sprayed from the water outlet. At this time, the flushing pipe 41 guides the liquid into the backflow chamber 40, pushes against the partition plate 43, makes the partition plate 43 slide, moves the limiting head 42 to the liquid accumulator cover 3, and then extends into the liquid accumulator cover 3 and is attached to the outer side of the movable ring 1, so as to limit the coaxiality of the movable ring 1 and the static ring 2. The counterweight is pulled away from the liquid accumulator cover 3 by the centrifugal force, and the elastic sheet 523 is far away from the liquid accumulator cover 3, so as to open the gap 31 when the centrifugal pump is running, and the liquid in the liquid accumulator cover 3 flows and circulates. When the centrifugal pump stops running, the elastic sheet 523 rebounds to block the gap between the gap 31 and the liquid accumulator cover 3 and the impeller 52, and the liquid in the liquid accumulator cover 3 is retained by the tension of the liquid. The next time the centrifugal pump is started, the movable ring 1 and the static ring 2 are lubricated in time, the communication between the backflow chamber 40 and the liquid accumulator cover 3 is disconnected, and then the liquid is accumulated in the backflow chamber 40. When the centrifugal pump is restarted, the backflow chamber 40 and the liquid accumulator cover 3 are connected again, and then the liquid in the liquid accumulator cover 3 is continuously introduced, and the dry burning prevention time is prolonged.

[0051] The above describes certain exemplary embodiments of the application by way of illustration only, and it is obvious to those skilled in the art that the described embodiments can be modified in various ways without departing from the spirit and scope of the application. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the application.

Claims

1. An energy-saving electric centrifugal pump sealing device, comprising a sealing cover (51), a motor (6) and a rotating shaft (61), wherein a stationary ring (2), a dynamic ring (1) and an impeller (52) are sequentially arranged on the rotating shaft (61), characterized in that: A liquid storage cover (3) is provided between the impeller (52) and the sealing cover (51), and slots (31) are provided on the liquid storage cover (3) in a circumferential array. A flushing pipe (41) is fixedly connected to the sealing cover (51), and the flushing pipe (41) infuses liquid into the liquid storage cover (3).

2. The energy-saving electric centrifugal pump sealing device according to claim 1, characterized in that: Elastic sheets (523) that fit the liquid storage cover (3) are arranged in a circumferential array on the impeller (52). The elastic sheets (523) rotate away from the liquid storage cover (3) as the impeller (52) rotates, thereby opening the slot (31).

3. The energy-saving electric centrifugal pump sealing device according to claim 1, characterized in that: A retaining cover (12) is fixedly provided on the rotating shaft (61), and a first spring (111) is provided between the moving ring (1) and the retaining cover (12).

4. The energy-saving electric centrifugal pump sealing device according to claim 1, characterized in that: It also includes a limiting assembly, which includes a limiting head (42) slidably connected to the sealing cover (51) in a circumferential array, and the limiting head (42) is driven to move into the liquid storage cover (3) to fit the dynamic ring (1).

5. The energy-saving electric centrifugal pump sealing device according to claim 1, characterized in that: It also includes a flushing mechanism (4), which includes a reflux chamber (40) provided on the sealing cover (51) and connected to the liquid storage cover (3), and the flushing pipe (41) is fixedly connected to the reflux chamber (40).

6. The energy-saving electric centrifugal pump sealing device according to claim 5, characterized in that: A partition (43) is slidably connected in the reflux chamber (40), and the partition (43) is provided with a hollow limiting head (42) in a circumferential array. The partition (43) moves with the liquid discharge from the flushing pipe (41), so that the limiting head (42) can infuse liquid into the liquid storage cover (3).

7. The energy-saving electric centrifugal pump sealing device according to claim 6, characterized in that: A liquid outlet is provided at the end of the outer side wall of the limiting head (42), and a guide hole (512) for the limiting head (42) to slide is provided on the sealing cover (51).

8. An energy-saving electric centrifugal pump, characterized in that: An energy-saving electric centrifugal pump sealing device comprising any one of claims 1 to 7, comprising a liquid storage cover (3), a sealing cover (51), a flushing pipe (41) and an impeller (52), and further comprising a pump casing (5) for carrying the impeller (52), the sealing cover (51) being arranged on the pump casing (5), the pump casing (5) comprising a water inlet and a water outlet, and the inlet of the flushing pipe (41) being arranged at the water outlet.

9. The energy-saving electric centrifugal pump according to claim 8, characterized in that: The impeller (52) is provided with a pressure relief valve (521) facing the inside of the liquid storage cover (3).

10. The energy-saving electric centrifugal pump according to claim 8, characterized in that: An end face bracket (50) is fixedly connected to one side of the pump housing (5), and a bearing (501) for supporting a rotating shaft (61) is provided in the end face bracket (50).

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