No-flush long shaft submersible pump

Abstract

The present invention relates to the technical field of submersible pumps, and specifically to a flush-free long-shaft submersible pump. An auxiliary impeller is fixed above the impeller, and the pump shaft drives the impeller and the auxiliary impeller to rotate. A shaft sleeve is mounted on the outside of the pump shaft above the auxiliary impeller, and a sealing step is provided on the shaft sleeve. A sealing seat is installed on the inner side of the pump cover, and a first cavity is formed between the sealing seat and the pump cover, and a second cavity is formed between the upper part of the sealing seat and the sealing step. A flexible sealing plate is provided inside the second cavity, and the upper space of the auxiliary impeller is connected to the first cavity, and the first cavity is connected to the second cavity. The bearing protection device of the present invention provides multiple protections for the bearing assembly of the pump, and the operation is more reliable, the service life of the pump is extended, and the safe use range of the pump under harsh external conditions is expanded.

Description

Technical Field

[0001] The invention relates to the technical field of submersible pumps, and in particular to a flushing-free long-shaft submersible pump. Background Art

[0002] The submersible part of a traditional long-axis submersible pump is supported by a sliding bearing and bears radial force. The sliding bearing needs to be flushed with clean liquid to cool it down and lubricate the friction surface. The flushing liquid can be the pumping medium or an external flushing source. When the process does not allow external flushing liquid to enter the pumping medium or the pumping process medium itself contains particles and cannot be used as a flushing liquid, the use of the submersible pump will be restricted. Summary of the invention

[0003] In view of the defects of the prior art, the present invention provides a flushing-free long-axis submersible pump, which eliminates the need for external flushing liquid, provides multiple protections for the bearing components of the pump, is more reliable, and extends the service life of the pump. The present invention provides a solution for use in arid and water-scarce areas or special applications where flushing is not allowed.

[0004] To achieve the above-mentioned purpose, the present invention proposes a flush-free long-axis submersible pump, comprising a pump body, a pump cover, an impeller, and a pump shaft. An auxiliary impeller is fixed above the impeller, and the pump shaft drives the impeller and the auxiliary impeller to rotate. A shaft sleeve is mounted on the outside of the pump shaft above the auxiliary impeller, and a sealing step is provided on the shaft sleeve. A sealing seat is installed on the inner side of the pump cover, and a first cavity is formed between the sealing seat and the pump cover, and a second cavity is formed between the upper part of the sealing seat and the sealing step. A flexible sealing plate is arranged inside the second cavity, and the upper space of the auxiliary impeller is connected to the first cavity, and the first cavity is connected to the second cavity.

[0005] Based on the above technical solution, when the pump is operating normally, the pump shaft drives the impeller and the auxiliary impeller to rotate, the impeller works to transport the medium, and the auxiliary impeller is a reverse impeller installed behind the impeller. The head generated is greater than or equal to the impeller back pressure, which plays a dynamic sealing role. When the pump is operating normally, it is sealed by the auxiliary impeller to protect the bearing components from being soaked by the pumped medium. At the same time, the suction action of the auxiliary impeller generates negative pressure, causing the flexible sealing plate to deform toward the auxiliary impeller side inside the second cavity, and a small gap is generated between the sealing plate and the sealing step set on the sleeve, ensuring that the sealing plate will not wear during operation and reducing heat generation.

[0006] Furthermore, the first cavity is connected to a first compressed air inlet pipe.

[0007] Based on the above technical solution, before stopping the pump, the compressed air valve on the first compressed air inlet pipe connected to the first cavity is opened, pressure is generated between the flexible sealing plate and the auxiliary impeller, the flexible sealing plate moves to the side away from the auxiliary impeller and contacts the shaft sleeve sealing step to form a sealing surface, and the pressurized gas leaks into the pump cavity through the small gap of the labyrinth seal, thereby preventing the medium from entering the sealing cavity.

[0008] Furthermore, a groove is provided on the outer surface of the sealing seat along the circumferential direction, and the groove and the inner surface of the pump cover form a second cavity. A through hole is provided on the pump cover and a first compressed air inlet pipe is installed.

[0009] Furthermore, one or more through holes are formed on the upper portion of the sealing seat, and the through holes connect the first cavity with the second cavity.

[0010] Preferably, a throttling bushing is arranged between the inner side of the sealing seat and the shaft sleeve.

[0011] Furthermore, a first oil seal is arranged between the pump shaft and the pump cover above the sealing step.

[0012] Furthermore, a bracket is installed on the upper part of the pump cover, the upper part of the bracket is detachably connected to the bearing frame, a rolling bearing is installed between the bearing frame and the pump shaft, the lower part of the bearing frame is detachably connected to the rolling bearing pressure cover, and a second oil seal is arranged between the lower end of the rolling bearing pressure cover and the shaft sleeve.

[0013] Based on the above technical solution, a rolling bearing is installed in the submersible pump, which eliminates the need for flushing fluid used in sliding bearings. The bearing protection device involved in this design provides multiple protections for the rolling bearing assembly of the pump, making the operation more reliable, extending the service life of the pump, and expanding the safe use range of the pump under harsh external conditions.

[0014] Furthermore, the space between the first oil seal and the second oil seal is connected to an inlet pipe and an outlet pipe.

[0015] Based on the above technical solution, there are two oil seals between the second cavity and the bearing body, the first oil seal is on the pump cover, and the second oil seal is at the lower end of the rolling bearing pressure cover. Two pipeline inlets and outlets are set in the space between the two oil seals. In extreme cases, when the first oil seal and the flexible sealing plate have failed, pressurized gas is introduced from the inlet pipe (compressed air inlet), and the gas is discharged from the outlet pipe at the bottom pump cover. If there is a medium leakage, the leaked liquid is also discharged at the same time to protect the rolling bearing.

[0016] Furthermore, a second oil seal gland is sleeved on the outside of the rolling bearing gland where the second oil seal is located.

[0017] Furthermore, the flush-free long-axis submersible pump also includes a liquid level probe, and the height of the monitoring end of the liquid level probe is lower than the highest point of the second oil seal gland.

[0018] Based on the above technical solution, the liquid level probe can monitor the medium position in real time. When the medium exceeds the height of the liquid level probe, pressurized gas is introduced from the inlet pipe (compressed air inlet), and the leaked liquid is discharged from the outlet pipe to protect the rolling bearing.

[0019] Beneficial effects of the present invention: The bearing protection device of the present invention provides multiple protections for the bearing assembly of the pump, makes the operation more reliable, prolongs the service life of the pump, and expands the safe use range of the pump under harsh external conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the present invention;

[0021] Figure 2 for Figure 1 A partial enlarged view of position A in the middle;

[0022] Figure 3 It is a schematic diagram of the structure of the present invention with a liquid level probe installed;

[0023] Figure 4 is a structural schematic diagram of the position of the flexible sealing plate;

[0024] In the figure: 1, pump body, 2, pump cover, 3, impeller, 4, pump shaft, 5, sub-impeller, 6, sleeve, 6.1, sealing step, 7, sealing seat, 7.1, groove, 7.2, through hole, 8, first cavity, 9, second cavity, 10, flexible sealing plate, 11, first compressed air inlet pipe, 12, first oil seal, 13, bracket, 14, bearing frame, 15, rolling bearing, 16, rolling bearing gland, 17, second oil seal, 18, inlet pipe, 19, outlet pipe, 20, second oil seal gland, 21, liquid level probe, 22, throttling bushing. DETAILED DESCRIPTION

[0025] The present invention will be further described below in conjunction with the accompanying drawings.

[0026] A flush-free long-axis submersible pump comprises a pump body 1, a pump cover 2, an impeller 3 and a pump shaft 4. An auxiliary impeller 5 is fixed above the impeller 3. The pump shaft 4 drives the impeller 3 and the auxiliary impeller 5 to rotate. A shaft sleeve 6 is mounted on the outside of the pump shaft 4 above the auxiliary impeller 5. A sealing step 6.1 is provided on the shaft sleeve 6. A sealing seat 7 is installed on the inner side of the pump cover 2. A first cavity 8 is formed between the sealing seat 7 and the pump cover 2. A second cavity 9 is formed between the upper part of the sealing seat 7 and the sealing step 6.1. A flexible sealing plate 10 is provided inside the second cavity 9. The upper space of the auxiliary impeller 5 is connected to the first cavity 8, and the first cavity 8 is connected to the second cavity 9.

[0027] Furthermore, the first cavity 8 is connected to a first compressed air inlet pipe 11 .

[0028] Furthermore, a groove 7.1 is formed on the outer surface of the sealing seat 7 along the circumferential direction, and the groove 7.1 and the inner surface of the pump cover 2 form a second cavity 9. A through hole is formed on the pump cover 2 and a first compressed air inlet pipe 11 is installed.

[0029] Furthermore, one or more through holes 7.2 are formed on the upper portion of the sealing seat 7, and the through holes 7.2 connect the first cavity 8 with the second cavity 9.

[0030] Preferably, a throttling bushing 22 is provided between the inner side of the sealing seat 7 and the shaft sleeve 6 .

[0031] Furthermore, a first oil seal 12 is provided between the pump shaft 4 and the pump cover 2 above the sealing step 6.1.

[0032] Furthermore, a bracket 13 is installed on the upper part of the pump cover 2, and the upper part of the bracket 13 is detachably connected to the bearing frame 14, a rolling bearing 15 is installed between the bearing frame 14 and the pump shaft 4, and the lower part of the bearing frame 14 is detachably connected to the rolling bearing pressure cover 16, and a second oil seal 17 is arranged between the lower end of the rolling bearing pressure cover 16 and the shaft sleeve 6.

[0033] Furthermore, the space between the first oil seal 12 and the second oil seal 17 is connected to an inlet pipe 18 and an outlet pipe 19 .

[0034] Furthermore, a second oil seal cover 20 is sleeved on the outside of the rolling bearing cover 16 where the second oil seal 17 is located.

[0035] Furthermore, the flush-free long-axis submersible pump further comprises a liquid level probe 21 , and the height of the monitoring end of the liquid level probe 21 is lower than the highest point of the second oil seal gland 20 .

[0036] Working process of this embodiment: When the pump is operating normally, the pump shaft 4 drives the impeller 3 and the auxiliary impeller 5 to rotate, the impeller 3 works to convey the medium, and the auxiliary impeller 5 is a reverse impeller installed behind the impeller 3. The head generated is greater than or equal to the impeller back pressure, which plays a dynamic sealing role. When the pump is operating normally, it is sealed by the auxiliary impeller 5 to protect the rolling bearing components from being soaked by the pumping medium. At the same time, the suction action of the auxiliary impeller 5 generates negative pressure, causing the flexible sealing plate 10 to deform toward the auxiliary impeller 5 side inside the second cavity 9, and a small gap is generated between the flexible sealing plate 10 and the sealing step set on the sleeve 6, ensuring that the flexible sealing plate 10 will not wear during operation and reduce heat generation.

[0037] Before stopping the pump, open the compressed air valve on the first compressed air inlet pipe 11 connected to the first cavity 8, and pressure is generated between the flexible sealing plate 10 and the auxiliary impeller 5. The flexible sealing plate 10 moves to the side away from the auxiliary impeller 5 and contacts the shaft sleeve sealing step to form a sealing surface. The pressurized gas leaks into the pump cavity through the tiny gap of the labyrinth seal, preventing the medium from entering the sealing cavity.

[0038] There are two oil seals between the second cavity 9 and the bearing body, the first oil seal is on the pump cover 2, and the second oil seal is at the lower end of the rolling bearing pressure cover 16. Two pipeline inlets and outlets (inlet pipeline 18 and outlet pipeline 19) are arranged in the space between the two oil seals. In extreme cases, when the first oil seal and the flexible sealing plate 10 have both failed, pressurized gas is introduced from the inlet pipeline 18 (compressed air inlet), and the gas is discharged from the outlet pipeline 19 at the bottom pump cover. If there is medium leakage, the liquid level probe 21 can monitor the medium level in real time. When the medium exceeds the height of the liquid level probe, pressurized gas is introduced from the inlet pipeline 18 (compressed air inlet), and the leaked liquid is discharged from the outlet pipeline 19 to protect the rolling bearing 15.

[0039] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of this patent.

Claims

1. A flush-free long-axis submersible pump, comprising a pump body, a pump cover, an impeller, and a pump shaft, characterized in that: An auxiliary impeller is fixed above the impeller, and the pump shaft drives the impeller and the auxiliary impeller to rotate. A shaft sleeve is mounted on the outside of the pump shaft above the auxiliary impeller, and a sealing step is arranged on the shaft sleeve. A sealing seat is installed on the inner side of the pump cover, and a first cavity is formed between the sealing seat and the pump cover, and a second cavity is formed between the upper part of the sealing seat and the sealing step. A flexible sealing plate is arranged inside the second cavity. The upper space of the auxiliary impeller is connected to the first cavity, and the first cavity is connected to the second cavity; the first cavity is connected to the first compressed air inlet pipe; a groove is arranged on the outer surface of the sealing seat in the circumferential direction, and the groove and the inner surface of the pump cover form a second cavity, and a groove is arranged on the pump cover. hole and install the first compressed air inlet pipe; one or more through holes are opened on the upper part of the sealing seat, and the through holes connect the first cavity with the second cavity; a throttling bushing is arranged between the inner side of the sealing seat and the sleeve; a first oil seal is arranged between the pump shaft and the pump cover above the sealing step; a bracket is installed on the upper part of the pump cover, the upper part of the bracket is detachably connected to the bearing frame, a rolling bearing is installed between the bearing frame and the pump shaft, the lower part of the bearing frame is detachably connected to the rolling bearing pressure cover, and a second oil seal is arranged between the lower end of the rolling bearing pressure cover and the sleeve; the space between the first oil seal and the second oil seal is connected to an inlet pipe and an outlet pipe.

2. The flush-free long-axis submersible pump according to claim 1, characterized in that: A second oil seal gland is sleeved on the outside of the rolling bearing gland where the second oil seal is located.

3. The flush-free long-axis submersible pump according to claim 2, characterized in that: The flush-free long-axis submersible pump also includes a liquid level probe, and the height of the monitoring end of the liquid level probe is lower than the highest point of the second oil seal gland.

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