Sealing water system for labyrinth seal at shaft end of steam pump

Abstract

The utility model discloses a steam pump shaft end labyrinth seal water sealing system which comprises a booster pump station, an integrated water station, a water return tank and a U-shaped water sealing cylinder, the water inlet end of the booster pump station is connected with a condensate pump outlet mother pipe end, the integrated water station comprises a filtering structure, the water inlet end of the filtering structure is connected with the water outlet end of the booster pump station, and the filtering structure is connected with the water inlet end of a labyrinth seal. The water inlet end of the water return tank is connected with the water outlet end of the labyrinth seal, the water inlet end of the U-shaped water seal cylinder is connected with the water outlet end of the water return tank, the water outlet end of the U-shaped water seal cylinder is connected with the condenser, and the water outlet end of the labyrinth seal is provided with a connecting pipeline connected to the steam pump booster pump. The sealing performance of the labyrinth seal is improved by arranging the sealing water system, the filtering structure is arranged to filter water entering the labyrinth seal, and the possibility that the labyrinth seal is damaged is reduced. Sealing water is led out from the condensate pump outlet main pipe end and then enters the condenser, original equipment serves as a water source, and the trouble of independently arranging a circulating water source is reduced.

Description

Technical Field

[0001] This utility model belongs to the technical field of sealing water systems, and relates to a labyrinth seal sealing water system for the shaft end of a steam pump. Background Technology

[0002] Steam-driven feedwater pumps are key equipment in thermal power generating units, and the reliability of their shaft end seals directly affects the safe operation of the unit. Currently, mechanical seals are mainly used. To improve the sealing performance of steam-driven feedwater pumps and reduce the inconvenience of frequent clogging of the sealing water filter screen of mechanical seals requiring manual cleaning, labyrinth seals are used for steam-driven feedwater pumps. However, there is currently a lack of a sealing water system that can cooperate with the labyrinth seal at the location of the steam-driven feedwater pump. Utility Model Content

[0003] To address the aforementioned problems, this invention proposes a labyrinth seal water sealing system for the shaft end of a steam pump, which effectively solves the problems in the prior art.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0005] A labyrinth seal water sealing system for a steam pump shaft end, comprising:

[0006] A booster pump station, comprising a direct water path, a booster water path connected in parallel to the direct water path, a booster pump installed in the booster water path, a shut-off valve installed at the inlet end of the booster pump, and the inlet end of the booster pump station connected to the outlet header of the condensate pump.

[0007] An integrated water station, comprising a filtration structure, wherein the inlet end of the filtration structure is connected to the outlet end of the booster pump station, and the outlet end of the filtration structure is connected to a regulating valve, wherein the outlet end of the regulating valve is connected to the labyrinth seal inlet end of the steam pump shaft.

[0008] The return water tank has an inlet end connected to the labyrinth seal outlet end of the steam pump shaft, a first vent is provided at the upper end of the return water tank, a shut-off valve is provided in the inlet pipe of the return water tank, and a water level gauge is provided in the return water tank.

[0009] The U-shaped water seal cylinder has an inlet end connected to the outlet end of the return water tank and an outlet end connected to the condenser. The U-shaped water seal cylinder is equipped with a second exhaust port. The inlet pipe of the U-shaped water seal cylinder is equipped with a shut-off valve and a regulating valve, and the outlet pipe of the U-shaped water seal cylinder is equipped with a shut-off valve.

[0010] The pump shaft end labyrinth seal outlet is equipped with a connecting pipe, which is connected to the pump pre-pump, and the connecting pipe is equipped with a shut-off valve.

[0011] Optionally, the booster water circuit and the filter structure are both provided in parallel with two circuits. The outlet of the booster water circuit is provided with a check valve and a solenoid valve, the inlet of the filter structure is provided with a solenoid valve, and the outlet of the filter structure is provided with a check valve.

[0012] Optionally, a water pressure gauge is connected in parallel with the filter structure, and the water pressure gauge is installed between the filter structure and the regulating valve.

[0013] Optionally, a water pressure gauge is provided at the water outlet end of the labyrinth seal on the pump shaft.

[0014] Optionally, a check valve is provided at the water inlet end of the labyrinth seal on the pump shaft.

[0015] Optionally, both the return water tank and the return water tank inlet pipe are equipped with overflow pipes, and the overflow pipe at the return water tank inlet pipe is equipped with a shut-off valve.

[0016] Optionally, the U-shaped water seal cylinder is provided with a water supply pipe at its inlet end, and the water supply pipe is provided with a shut-off valve.

[0017] Optionally, the second exhaust port is provided with a shut-off valve.

[0018] Compared with existing technologies, this invention has the following advantages: by setting up a sealing water system, the sealing performance of the labyrinth seal is improved, and by setting up a filtration structure to filter the water entering the labyrinth seal, the possibility of damage to the labyrinth seal is reduced. The sealing water is led out from the condensate pump outlet header and then enters the condenser, using the existing equipment as a water source, reducing the hassle of setting up a separate circulating water source. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present utility model.

[0020] Attached reference numerals: 1. Booster pump station; 11. Direct water connection; 12. Booster water circuit; 13. Booster pump; 2. Integrated water station; 21. Filter structure; 3. Return water tank; 31. First vent; 32. Overflow pipe; 4. U-shaped water seal cylinder; 41. Second vent; 42. Makeup water pipe; 5. Connecting pipeline; 6. Condensate pump outlet header; 7. Steam pump; 8. Condenser; 9. Pre-pump. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Please see Figure 1 This utility model discloses a pump shaft end labyrinth seal sealing water system, including a booster pump station 1, an integrated water station 2, a return water tank 3, and a U-shaped water seal cylinder 4. The booster pump station 1 includes a direct water passage 11, a booster water passage 12 connected in parallel to the direct water passage 11, a booster pump 13 installed in the booster water passage 12, a shut-off valve installed at the inlet end of the booster pump 13, and the inlet end of the booster pump station 1 connected to the outlet header 6 of the condensate pump. The integrated water station 2 includes a filter structure 21, the inlet end of the filter structure 21 connected to the outlet end of the booster pump station 1, and a regulating valve connected to the outlet end of the filter structure 21. The outlet end of the regulating valve is connected to the pump shaft end labyrinth seal. The water inlet and return water tank 3 are connected to the labyrinth seal outlet of the steam pump 7 shaft. The upper end of the return water tank 3 is equipped with a first vent 31. The water inlet pipe of the return water tank 3 is equipped with a shut-off valve. The return water tank 3 is equipped with a water level gauge. The water inlet of the U-shaped water seal cylinder 4 is connected to the water outlet of the return water tank 3. The water outlet is connected to the condenser 8. The U-shaped water seal cylinder 4 is equipped with a second vent 41. The water inlet pipe of the U-shaped water seal cylinder 4 is equipped with a shut-off valve and a regulating valve. The water outlet pipe of the U-shaped water seal cylinder 4 is equipped with a shut-off valve. The water outlet of the labyrinth seal of the steam pump 7 shaft is equipped with a connecting pipe 5. The connecting pipe 5 is connected to the pre-pump 9 of the steam pump 7. The connecting pipe 5 is equipped with a shut-off valve.

[0023] Specifically, sealing water is drawn from the outlet header 6 of the condensate pump, pressurized by the booster pump station 1, and then filtered through the filter structure 21. The filtered liquid enters the labyrinth seal at the shaft end of the steam pump 7, flows back to the return water tank 3 after passing through the labyrinth seal, and then flows back to the condenser 8 after passing through the U-shaped water seal cylinder 4. The unloading water from the labyrinth seal enters the pre-pump 9 through a pipeline.

[0024] In this way, by setting up a sealing water system, the sealing performance of the labyrinth seal is improved, and the filter structure 21 filters the water entering the labyrinth seal, reducing the possibility of damage to the labyrinth seal. The sealing water is led out from the condensate pump outlet header 6 and then enters the condenser 8, using the existing equipment as a water source, reducing the trouble of setting up a separate circulating water source.

[0025] In some feasible embodiments, the booster pump 13 can be configured as a variable frequency pump to facilitate pressure regulation. In this embodiment, the booster pump 13 maintains a pressure difference ≥0.5MPa between the sealing water supply pressure and the outlet pressure of the pre-pump 9. The filter structure 21 can be selected from existing market products that meet the requirements for filtration accuracy, water pressure, and flow rate. The return water tank 3 is a rectangular tank, and the U-shaped water seal cylinder 4 is a U-shaped tube. By setting the U-shaped water seal cylinder 4, the gas flow between the condenser 8 and the sealing water system is reduced, ensuring that the negative pressure of the condenser is not disrupted. The return water tank 3 and the U-shaped water seal cylinder 4 are provided with a first exhaust port 31 and a second exhaust port 41 to facilitate the balancing of gas pressure changes caused by water level changes in the return water tank 3 and the U-shaped water seal cylinder 4.

[0026] Among them, the regulating valve is a flow regulating valve, which adjusts the water flow by cooperating with corresponding sensors. For example, the regulating valve at the shaft end of the steam pump 7 adjusts the sealing water flow based on the temperature sensor at the shaft end, the speed, etc., according to the speed of the steam pump and the amount of heat at the shaft end. The opening of the regulating valve follows the change of the sealing water temperature.

[0027] In some feasible methods, the water level gauge installed in the return water tank 3 is a flap water level gauge and a guided wave radar water level gauge, which are used to detect the water level in the return water tank 3. Together with the regulating valve at the position of the inlet pipe of the U-shaped water seal cylinder 4, the water flow rate entering the U-shaped water seal cylinder 4 is adjusted according to the water level height set in the return water tank 3.

[0028] A differential pressure gauge is connected in parallel to the filter structure 21. By detecting the pressure difference between the two ends of the filter structure, the blockage of the filter structure 21 can be sensed. A water pressure gauge is installed between the filter structure 21 and the regulating valve to detect the water supply pressure. A water pressure gauge is installed at the water outlet end of the labyrinth seal on the shaft end of the steam pump 7 to detect the return water pressure.

[0029] In some feasible methods, a check valve is installed at the water inlet end of the labyrinth seal on the pump shaft. By installing the check valve, the possibility of water backflow is reduced when the booster pump 13 fails to supply pressure.

[0030] As a specific embodiment of the pump shaft end labyrinth seal sealing water system provided in the application, the booster water path 12 and the filter structure 21 are both arranged in parallel with two paths. The outlet end of the booster water path 12 is equipped with a check valve and a solenoid valve, and the inlet end of the filter structure 21 is equipped with a solenoid valve and the outlet end is equipped with a check valve.

[0031] Overall, by setting up two pressurized water paths 12 and a filter structure 21, and providing a backup line, the possibility of the sealed water system failing after damage to the pressurized water path 12 or the filter structure 21 is reduced. At the same time, the filter structure 21 requires regular cleaning of the dirt within it; by setting up two filter structures 21, it is convenient to switch water paths during cleaning.

[0032] As a specific embodiment of the pump shaft end labyrinth seal sealing water system provided in the application, both the return water tank 3 and the return water tank 3 inlet pipe are provided with overflow pipes 32, and the overflow pipes 32 at the return water tank 3 inlet pipe position are provided with shut-off valves.

[0033] It should be understood that by setting the overflow pipe 32, the impact on the return water system is reduced when the return water tank 3 is full.

[0034] As a specific embodiment of the labyrinth seal water system for a steam pump shaft end provided in the application, a water supply pipe 42 is provided at the water inlet end of the U-shaped water seal cylinder 4, and a shut-off valve is provided on the water supply pipe 42.

[0035] It should be understood that by setting up the water supply pipe 42 to replenish water in the sealing water system, the impact of gas discharge on the water level of the U-shaped water seal cylinder 4 is reduced.

[0036] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A labyrinth seal water sealing system for a steam pump shaft end, characterized in that, include: A booster pump station (1) includes a direct water path (11), a booster water path (12) connected in parallel to the direct water path (11), a booster pump (13) installed in the booster water path (12), a shut-off valve installed at the inlet end of the booster pump (13), and the water inlet end of the booster pump station (1) connected to the outlet header of the condensate pump. An integrated water station (2) includes a filter structure (21), the inlet end of which is connected to the outlet end of the booster pump station (1), and the outlet end of which is connected to a regulating valve, the outlet end of which is connected to the labyrinth seal inlet end of the steam pump shaft. The return water tank (3) has its inlet end connected to the labyrinth seal outlet end of the steam pump shaft. The upper end of the return water tank (3) is provided with a first exhaust port (31). The inlet pipe of the return water tank (3) is provided with a shut-off valve. The return water tank (3) is provided with a water level gauge. U-shaped water seal cylinder (4), the water inlet end of the U-shaped water seal cylinder (4) is connected to the water outlet end of the return water tank (3), the water outlet end is connected to the condenser, the U-shaped water seal cylinder (4) is provided with a second exhaust port (41), the water inlet pipe of the U-shaped water seal cylinder (4) is provided with a shut-off valve and the regulating valve, and the water outlet pipe of the U-shaped water seal cylinder (4) is provided with a shut-off valve; The pump shaft end labyrinth seal outlet end is provided with a connecting pipe (5), which is connected to the pump pre-pump, and the connecting pipe (5) is provided with a shut-off valve.

2. The water sealing system for a steam pump shaft end labyrinth seal according to claim 1, characterized in that: The booster water path (12) and the filter structure (21) are both connected in parallel with two paths. The booster water path (12) is equipped with a check valve and a solenoid valve at the outlet end. The filter structure (21) is equipped with a solenoid valve at the inlet end and a check valve at the outlet end.

3. The water sealing system for a steam pump shaft end labyrinth seal according to claim 1, characterized in that: The filter structure (21) is connected in parallel with a water pressure gauge, and the water pressure gauge is installed between the filter structure (21) and the regulating valve.

4. The water sealing system for a steam pump shaft end labyrinth seal according to claim 1, characterized in that: A water pressure gauge is installed at the water outlet end of the labyrinth seal on the shaft end of the steam pump.

5. The water sealing system for a steam pump shaft end labyrinth seal according to claim 1, characterized in that: A check valve is installed at the water inlet end of the labyrinth seal on the pump shaft.

6. The water sealing system for a steam pump shaft end labyrinth seal according to claim 1, characterized in that: Both the return water tank (3) and the inlet pipe of the return water tank (3) are equipped with overflow pipes (32), and the overflow pipe (32) at the position of the inlet pipe of the return water tank (3) is equipped with a shut-off valve.

7. The water sealing system for a steam pump shaft end labyrinth seal according to claim 1, characterized in that: The U-shaped water seal cylinder (4) is equipped with a water supply pipe (42) at its water inlet end, and the water supply pipe (42) is equipped with a shut-off valve.

8. The water sealing system for a steam pump shaft end labyrinth seal according to claim 1, characterized in that: The second exhaust port (41) is equipped with a shut-off valve.

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