Rapid cooling process system device after shutdown of steam turbine

Abstract

The utility model discloses a rapid cooling process system device after shutdown of a steam turbine, relates to the field of heat energy power engineering, and is used for solving the problems that media in a cylinder body of an existing steam turbine are insufficient in flowability and low in cooling speed. The rotary dehumidifier supplies external air into a steam-water separation reheater through a connecting pipe, the external air is divided into a high-pressure cylinder airflow cooling path and a medium-pressure cylinder airflow cooling path through the steam-water separation reheater, and finally the external air is exhausted through a low-pressure cylinder; the high-pressure cylinder airflow cooling path comprises a high-pressure cylinder connected with the steam-water separation reheater through a high-pressure cylinder steam exhaust pipeline, and the high-pressure cylinder is connected with a main steam pipeline through a high-pressure steam inlet pipeline and then connected with a low-pressure cylinder through a bypass exhaust pipeline via a condenser. The medium-pressure cylinder airflow cooling path comprises a medium-pressure cylinder connected with the steam-water separation reheater through a medium-pressure steam inlet pipeline, and the medium-pressure cylinder is connected with the low-pressure cylinder through a medium-pressure steam exhaust pipeline. And the fluidity in the cylinder body is improved, and meanwhile, rapid cooling of the cylinder body is guaranteed.

Description

Technical Field

[0001] This utility model belongs to the field of thermal power engineering, specifically relating to a rapid cooling process system device after a steam turbine is shut down. Background Technology

[0002] After a nuclear power plant turbine unit is shut down for overhaul, the turbine is continuously turned around for natural cooling. It takes more than 120 hours to cool the metal temperature of the high and intermediate pressure cylinders of the turbine to below 120°C (turning and shut-down conditions). For units with short overhaul periods, this situation seriously restricts the overhaul progress, prolongs the overhaul time, and affects the completion of power generation tasks.

[0003] The slow temperature drop of the high and intermediate pressure cylinders of the steam turbine is due to insufficient fluidity inside and outside the cylinder, and the suppression of the heat exchange environment by objective factors. Specifically, this is manifested in the following two aspects: 1. The temperature difference between the residual high-temperature and high-density steam inside the cylinder and the cylinder metal is small, and the medium inside the cylinder has no fluidity or severely insufficient fluidity. 2. The cylinder is covered by a thick layer of insulation material, which affects the heat exchange between the cylinder and the external environment. Utility Model Content

[0004] The purpose of this invention is to provide a rapid cooling process system for steam turbines after shutdown, which solves the problems of insufficient fluidity of the medium inside the existing steam turbine cylinder and slow cooling speed. While improving the fluidity inside the cylinder, it ensures the requirement for rapid cooling of the cylinder.

[0005] The technical solution adopted by this utility model to solve its technical problem is: a rapid cooling process system device after a steam turbine shutdown, comprising: supplying external air into the rotor dehumidifier of a steam-water separator reheater through a connecting pipe; the external air being split into two paths by the steam-water separator reheater: a high-pressure cylinder airflow cooling path and a medium-pressure cylinder airflow cooling path; and finally discharging the external air through a low-pressure cylinder.

[0006] The high-pressure cylinder airflow cooling path includes the high-pressure cylinder connected to the steam-water separator reheater via the high-pressure cylinder exhaust pipe, the high-pressure cylinder connected to the main steam pipe via the high-pressure steam inlet pipe, and then connected to the low-pressure cylinder via the bypass pipe and condenser.

[0007] The intermediate-pressure cylinder airflow cooling path includes an intermediate-pressure cylinder connected to a steam-water separator reheater via an intermediate-pressure steam inlet pipe, and an intermediate-pressure cylinder connected to a low-pressure cylinder via an intermediate-pressure steam exhaust pipe.

[0008] In the aforementioned rapid cooling process system for a steam turbine after shutdown, the connecting pipe of the turbine dehumidifier is connected to the manhole of the steam-water separator reheater via a flange.

[0009] The aforementioned rapid cooling process system for a steam turbine after shutdown includes a rotary dehumidifier that pressurizes air from the external environment and then delivers the air to a steam-water separator reheater for diversion.

[0010] In the aforementioned rapid cooling process system for a steam turbine after shutdown, a high-pressure regulating valve and a high-pressure main steam valve are sequentially installed on the high-pressure steam inlet pipe between the high-pressure cylinder and the main steam pipe.

[0011] In the aforementioned rapid cooling process system for a steam turbine after shutdown, a condenser bypass valve group is provided between the bypass pipe and the condenser.

[0012] The aforementioned rapid cooling process system for a steam turbine after shutdown includes a medium-pressure main steam valve and a medium-pressure regulating valve sequentially installed on the medium-pressure steam inlet pipeline between the steam-water separator reheater and the medium-pressure cylinder.

[0013] The aforementioned rapid cooling process system for a steam turbine after shutdown involves ensuring rapid cooling of each cylinder by connecting devices and controlling the opening of the high-pressure steam inlet valve group and the intermediate-pressure steam inlet valve group after the steam turbine is tripped and shut down.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: The rapid cooling process system device for turbine shutdown provided by this utility model does not require additional interfaces, is simple to operate, and is fast. Secondly, the rotor dehumidifier filters and removes dust from the ambient air, heats it, and introduces it into the cylinder, which can ensure the cleanliness of the system, reduce the temperature difference between the cooling medium and the cylinder, and lower the cylinder temperature. Thirdly, this device utilizes the existing maintenance equipment of the power plant, without the need to purchase and install new equipment, which can save costs. Attached Figure Description

[0015] Figure 1 The diagram shows an overall schematic of a rapid cooling process system for a steam turbine after shutdown, as described in this utility model.

[0016] Explanation of the numbers in the diagram: 1. High-pressure cylinder II 2. Medium-pressure cylinder II 3. Low-pressure cylinder II 4. Condenser II 5. Steam-water separator reheater II 6. High-pressure regulating valve II 7. High-pressure main steam valve II 8. Medium-pressure regulating valve II 9. Medium-pressure main steam valve II 10. Condenser bypass valve group II 11. Main steam pipeline II 12. High-pressure cylinder exhaust pipeline II 13. Medium-pressure steam inlet pipeline II 14. High-pressure steam inlet pipeline II 15. Bypass pipeline II 16. Medium-pressure exhaust pipeline II 17. Rotary dehumidifier. Detailed Implementation

[0017] To address the problems of insufficient fluidity and slow cooling rate of the medium within the cylinder of existing steam turbines, this utility model provides a rapid cooling process system device after turbine shutdown. For example... Figure 1As shown, the device includes: a rotary dehumidifier 17 that supplies external air into the steam-water separator reheater 5 through a connecting pipe; the external air is split into two paths by the steam-water separator reheater 5: a high-pressure cylinder 1 airflow cooling path and a medium-pressure cylinder 2 airflow cooling path; and finally, the external air is discharged through the low-pressure cylinder 3; the connecting pipe of the rotary dehumidifier 17 is connected to the manhole of the steam-water separator reheater 5 through a flange, which can pressurize the air in the external environment and then deliver the air to the steam-water separator reheater 5 for splitting.

[0018] The airflow cooling path of the high-pressure cylinder 1 includes the high-pressure cylinder 1 connected to the steam-water separator reheater 5 via the high-pressure cylinder exhaust pipe 12. The high-pressure cylinder 1 is connected to the main steam pipe 11 via the high-pressure steam inlet pipe 14. The high-pressure regulating valve 6 and the high-pressure main steam valve 7 are sequentially installed on the high-pressure steam inlet pipe 14 between the high-pressure cylinder 1 and the main steam pipe 11. The high-pressure cylinder 3 is then connected to the low-pressure cylinder 3 via the condenser 4 via the bypass pipe 15. A condenser bypass valve group 10 is installed between the bypass pipe 15 and the condenser 4.

[0019] The airflow cooling path of the intermediate-pressure cylinder 2 includes the intermediate-pressure cylinder 2 connected to the steam-water separator reheater 5 via the intermediate-pressure steam inlet pipe 13, and the intermediate-pressure cylinder 2 connected to the low-pressure cylinder 3 via the intermediate-pressure steam exhaust pipe 16. The intermediate-pressure steam inlet pipe 13 between the steam-water separator reheater 5 and the intermediate-pressure cylinder 2 is sequentially equipped with an intermediate-pressure main steam valve 9 and an intermediate-pressure regulating valve 8.

[0020] This rapid cooling device utilizes the existing flow channels of the turbine process system, connecting to its dedicated turbine dry air maintenance device. Treated air is continuously introduced into the process system piping to improve the flow of the medium inside the high-pressure cylinder 1 and intermediate-pressure cylinder 2. The cooler medium, flowing over the warmer cylinder surface, exchanges heat with the cylinder surface, cooling it and achieving rapid cooling. This device is primarily used after the turbine is shut down. When the manhole of the steam-water separator reheater 5 is opened, the dehumidifier 17 is connected via the manhole flange bolts, and heated air is supplied to the steam-water separator reheater 5. The heated air then enters the high-pressure cylinder 1 and intermediate-pressure cylinder 2 through the high-pressure cylinder exhaust pipe 12 and the intermediate-pressure cylinder inlet pipe 13, respectively, to cool the cylinder body and rotor.

[0021] In this rapid cooling device, the airflow direction within the airflow cooling path of the high-pressure cylinder 1 is as follows:

[0022] Rotary dehumidifier 17, connecting pipe, steam-water separator reheater 5, high-pressure cylinder exhaust pipe 12, high-pressure cylinder 1, high-pressure regulating valve 6, high-pressure main steam valve 7, high-pressure steam inlet pipe 14, main steam pipe 11, bypass pipe 15, condenser bypass valve group 10, condenser 4, low-pressure cylinder 3, atmosphere.

[0023] The airflow direction within the airflow cooling path of the intermediate pressure cylinder 2 is as follows:

[0024] Rotary dehumidifier 17, connecting pipe, steam-water separator reheater 5, medium-pressure steam inlet pipe 13, medium-pressure main steam valve 9, medium-pressure regulating valve 8, medium-pressure cylinder 2, medium-pressure exhaust pipe 16, low-pressure cylinder 3, atmosphere.

[0025] It should be noted that the combination of the technical features in the embodiments of this utility model is not limited to the combination methods recorded in the embodiments of this utility model or the combination methods recorded in specific embodiments. All technical features recorded in this utility model can be freely combined or combined in any way, unless there is a contradiction between them.

[0026] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications or equivalent substitutions made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A system for rapid cooling of a steam turbine after shutdown, characterized in that The device comprises a rotary dehumidifier (17) for supplying external air into a steam-water separation reheater (5) through a connecting pipe, the external air is divided into two paths of a high-pressure cylinder (1) airflow cooling path and a medium-pressure cylinder (2) airflow cooling path through the steam-water separation reheater (5), and finally the external air is discharged through a low-pressure cylinder (3); The high-pressure cylinder (1) airflow cooling path comprises the high-pressure cylinder (1) connected with the steam-water separation reheater (5) through a high-pressure cylinder exhaust pipe (12), the high-pressure cylinder (1) is connected with a main steam pipe (11) through a high-pressure inlet steam pipe (14), and then connected with the low-pressure cylinder (3) through a condenser (4) and a bypass pipe (15); the medium-pressure cylinder (2) airflow cooling path comprises the medium-pressure cylinder (2) connected with the steam-water separation reheater (5) through a medium-pressure inlet steam pipe (13), and the medium-pressure cylinder (2) is connected with the low-pressure cylinder (3) through a medium-pressure exhaust pipe (16).

2. A system for rapid cooling of a steam turbine after shutdown according to claim 1, characterized in that The connecting pipe of the rotary dehumidifier (17) is connected with a manhole door of the steam-water separation reheater (5) through a flange.

3. A system for rapid cooling of a steam turbine after shutdown according to claim 2, characterized in that The rotary dehumidifier (17) can pressurize the air in the external environment and then deliver the air to the steam-water separation reheater (5) for division.

4. A system for rapid cooling of a steam turbine after shutdown according to claim 1, characterized in that A high-pressure regulating valve (6) and a high-pressure main valve (7) are sequentially arranged on the high-pressure inlet steam pipe (14) between the high-pressure cylinder (1) and the main steam pipe (11).

5. A system for rapid cooling of a steam turbine after shutdown according to claim 1, characterized in that A condenser bypass valve group (10) is arranged between the bypass pipe (15) and the condenser (4).

6. A system for rapid cooling of a steam turbine after shutdown according to claim 1, characterized in that A medium-pressure main valve (9) and a medium-pressure regulating valve (8) are sequentially arranged on the medium-pressure inlet steam pipe (13) between the steam-water separation reheater (5) and the medium-pressure cylinder (2).

7. A system for rapid cooling of a steam turbine after shutdown according to any of claims 1-6, characterized in that After the turbine is stopped by braking, the opening degrees of the high-pressure inlet steam valve group and the medium-pressure inlet steam valve group are controlled through the connecting device to ensure the rapid cooling of each cylinder.

Images