Underground coal mine submerged type water feeding pump sealing structure

Abstract

A sealing structure of an underground coal mine submerged type water feeding pump comprises a motor, a motor base, a base and an outlet pipe which are sequentially and fixedly installed from top to bottom, a main shaft is connected to an output shaft of the motor, a bearing assembly is installed on the top face of the base, the main shaft penetrates through the center of the bearing assembly, and an auxiliary impeller is installed on the main shaft and located in the base. The sealing body is fixedly installed on the inner bottom face of the base, the auxiliary impeller is located in the sealing body, the auxiliary impeller comprises a wheel disc, a hub arranged in the center of the wheel disc and blades circumferentially arranged on the wheel disc, the hub and the main shaft are installed through threads, the hub penetrates out of the upper end of the sealing body, and a lock nut is installed on the main shaft and located at the upper end of the auxiliary impeller. A non-contact dynamic sealing structure is adopted, the sealing structure is free of maintenance, maintenance work is saved, and normal use of the water feeding pump is guaranteed.

Description

Technical Field

[0001] The utility model relates to a submersible feed water pump for use in coal mines, in particular to a sealing structure of a submersible feed water pump for use in coal mines. Background Art

[0002] The submersible feed water pump is installed in front of the main drainage pump in the coal mine and is used in series with the main drainage pump to form a positive pressure water supply at the inlet of the main drainage pump, so as to ensure that the main drainage pump can be started without vacuum extraction and eliminate the cavitation phenomenon of the main drainage pump. It is widely used in coal mines.

[0003] The feed water pump mainly includes a motor, a motor base, a base, an outlet pipe, a pump pipe, a guide vane, a bell mouth, a main shaft connected to the output shaft of the motor, a pump shaft connected to the main shaft, an impeller connected to the pump shaft, and a bearing assembly installed on the top surface of the base. The main shaft passes through the center of the bearing assembly. To prevent the water flowing through the outlet pipe from entering the bearing assembly and the motor, packing seal is usually carried out between the base and the main shaft. The packing seal is a contact seal structure, which is easy to wear during long-term operation and needs regular maintenance. Since the feed water pump is installed in the coal mine underground where the space is narrow and it is inconvenient to operate, the maintenance work is time-consuming and laborious. To overcome the problems of the above packing seal, the existing feed water pump adopts a secondary impeller for non-contact dynamic seal structure. The existing secondary impeller is fixedly installed on the main shaft. Due to the high requirement for the axial seal clearance of the non-contact dynamic seal of the secondary impeller, the axial displacement of the submersible feed water pump needs to be adjusted, and there is a phenomenon of scraping between the secondary impeller and the main shaft, resulting in the feed water pump being unable to be used normally. Summary of the Invention

[0004] The utility model is to solve the above technical problems and provides a sealing structure of a submersible feed water pump for use in coal mines. The sealing structure adopts a non-contact dynamic seal structure, which is maintenance-free, saves maintenance work and ensures the normal use of the feed water pump.

[0005] The technical solution of the utility model is as follows:

[0006] A sealing structure of a submersible feed water pump for use in coal mines, including a motor, a motor base, a base and an outlet pipe which are fixedly installed in sequence from top to bottom. A main shaft is connected to the output shaft of the motor. A bearing assembly is installed on the top surface of the base. The main shaft passes through the center of the bearing assembly. A secondary impeller is installed on the main shaft inside the base. A sealing body is fixedly installed on the inner bottom surface of the base. The secondary impeller is located inside the sealing body. The special feature is that: the secondary impeller includes a wheel disc, a hub arranged at the center of the wheel disc, and blades circumferentially arranged on the wheel disc. The hub is installed on the main shaft through a thread. The hub passes out from the upper end of the sealing body. A lock nut is installed on the main shaft above the secondary impeller.

[0007] Furthermore, the blades are located on the upper surface of the wheel disc, and the sealing effect is good.

[0008] Further, the clearance between the blade and the inner top surface of the seal body is 1 mm - 2 mm.

[0009] Further, the outer circular surface at the upper end of the hub is a regular polygon, which is convenient for adjusting the auxiliary impeller with a wrench.

[0010] Further, the seal body includes a seal main body fixedly installed on the inner bottom surface of the base, and a seal upper cover fixedly installed on the top surface of the seal main body.

[0011] The beneficial effects of the present utility model are as follows:

[0012] 1. During the rotation of the auxiliary impeller following the main shaft, a centrifugal force is generated on the water entering the seal body. This centrifugal force is greater than the pressure of the pump, thereby controlling the water entering the seal body below the auxiliary impeller, preventing water from entering the bearing assembly and the interior of the motor. The auxiliary impeller and the seal body form a non-contact dynamic seal structure, and the seal structure is maintenance-free, saving maintenance work.

[0013] 2. Since the auxiliary impeller is installed on the main shaft through threads, a lock nut is installed on the main shaft above the auxiliary impeller through threads. The clearance between the auxiliary impeller and the inner top surface of the seal body is adjusted through threads, and the lock nut is tightened to prevent loosening, improving the sealing effect and ensuring the normal use of the feed water pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic structural diagram of the present utility model;

[0015] Figure 2 is Figure 1 the enlarged view of part A in

[0016] Figure 3 is Figure 2 the top view of the auxiliary impeller in

[0017] In the figure: 1 - motor, 2 - motor base, 3 - base, 4 - outlet pipe, 5 - main shaft, 6 - bearing assembly, 7 - auxiliary impeller, 8 - lock nut, 9 - seal body, 701 - wheel disc, 702 - hub, 703 - blade, 901 - seal main body, 902 - seal upper cover. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] As Figures 1 - 3As shown in the figure, a submersible feed water pump sealing structure for use in coal mines includes a motor 1, a motor base 2, a base 3, and an outlet pipe 4 that are fixedly installed in sequence from top to bottom. A main shaft 5 is connected to the output shaft of the motor 1. A bearing assembly 6 is installed on the top surface of the base 3. The main shaft 5 passes through the center of the bearing assembly 6. A secondary impeller 7 is installed inside the base 3 on the main shaft 5. The secondary impeller 7 includes a wheel disc 701, a hub 702 provided at the center of the wheel disc 701, and blades 703 circumferentially arranged on the wheel disc 701. The hub 702 of the secondary impeller 7 is installed on the main shaft 5 by means of a thread. The outer circumferential surface of the upper end of the hub 702 is a regular polygon, and a lock nut 8 is installed on the main shaft 5 above the hub 702 by means of a thread. A seal body 9 is fixedly installed on the inner bottom surface of the base 3. The seal body 9 includes a seal main body 901 fixedly installed on the inner bottom surface of the base 3 and a seal upper cover 902 fixedly installed on the top surface of the seal main body 901. The secondary impeller 7 is located inside the seal body 9. The upper end of the hub 702 passes through the seal upper cover 902. The gap between the blades 703 and the seal upper cover 902 is 1.5 mm.

[0019] The working principle of the present utility model is as follows:

[0020] During installation, first adjust the axial movement of the feed water pump, and then adjust the secondary impeller 7 upward by means of a thread so that the blades 703 abut against the inner top surface of the seal end cover. Then adjust the secondary impeller 7 downward by 1.5 mm by means of a thread, and lock the secondary impeller 7 with the lock nut 8.

[0021] During operation, the motor 1 drives the impeller connected to the pump shaft to rotate, so that the water in the mine enters from the water inlet of the submersible feed water pump and is discharged from the water outlet on one side of the outlet pipe 4. At this time, the pressurized water enters the seal body 9. During the rotation of the secondary impeller 7 following the main shaft 5, a centrifugal force is generated on the water entering the seal body 9. This centrifugal force is greater than the pressure of the pump, and thus the water entering the seal body 9 is controlled below the secondary impeller 7, preventing the water from entering the bearing assembly 6 and the interior of the motor 1.

[0022] The above are only specific embodiments of the present utility model and are not used to limit the present utility model. For those skilled in the art, various modifications and changes can be made to the present utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A sealing structure for a submersible water pump used in coal mines, comprising a motor, a motor seat, a base and an outlet pipe fixedly installed in sequence from top to bottom, a main shaft connected to the output shaft of the motor, a bearing assembly installed on the top surface of the base, the main shaft passes through the center of the bearing assembly, an auxiliary impeller is installed on the main shaft in the base, a sealing body is fixedly installed on the inner bottom surface of the base, the auxiliary impeller is located in the sealing body, and is characterized in that: The auxiliary impeller includes a wheel disc, a hub arranged at the center of the wheel disc, and blades arranged circumferentially on the wheel disc. The hub is installed with the main shaft through threads. The hub passes through the upper end of the sealing body, and a lock nut is installed on the main shaft at the upper end of the auxiliary impeller.

2. The sealing structure of the submersible water pump for underground coal mine according to claim 1 is characterized in that: The blades are located on the upper surface of the wheel disc.

3. The sealing structure of the submersible water pump for underground coal mine according to claim 2 is characterized in that: The gap between the blade and the top surface of the sealing body is 1mm-2mm.

4. The sealing structure of the submersible water pump for underground coal mine according to claim 1 is characterized in that: The outer circumferential surface of the upper end of the hub is a regular polygon.

5. The sealing structure of the submersible water pump for underground coal mine according to claim 1 is characterized in that: The sealing body comprises a sealing main body fixedly mounted on the inner bottom surface of the base, and a sealing upper cover fixedly mounted on the top surface of the sealing main body.

Images