CN117418909A - Method for stopping shaft seal steam turbine - Google Patents
Method for stopping shaft seal steam turbine Download PDFInfo
- Publication number
- CN117418909A CN117418909A CN202311481898.4A CN202311481898A CN117418909A CN 117418909 A CN117418909 A CN 117418909A CN 202311481898 A CN202311481898 A CN 202311481898A CN 117418909 A CN117418909 A CN 117418909A
- Authority
- CN
- China
- Prior art keywords
- steam
- pressure
- valve
- shaft seal
- closing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 23
- 238000003303 reheating Methods 0.000 claims abstract description 22
- 230000001105 regulatory effect Effects 0.000 claims description 55
- 239000002918 waste heat Substances 0.000 claims description 45
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 41
- 239000007789 gas Substances 0.000 claims description 20
- 230000001276 controlling effect Effects 0.000 claims description 15
- 238000002309 gasification Methods 0.000 claims description 8
- 238000000926 separation method Methods 0.000 claims description 6
- 238000010248 power generation Methods 0.000 abstract description 2
- 239000010842 industrial wastewater Substances 0.000 description 3
- 238000012946 outsourcing Methods 0.000 description 3
- 238000007789 sealing Methods 0.000 description 3
- 238000009825 accumulation Methods 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 241001584775 Tunga penetrans Species 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D21/00—Shutting-down of machines or engines, e.g. in emergency; Regulating, controlling, or safety means not otherwise provided for
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
- F01D11/02—Preventing or minimising internal leakage of working-fluid, e.g. between stages by non-contact sealings, e.g. of labyrinth type
- F01D11/04—Preventing or minimising internal leakage of working-fluid, e.g. between stages by non-contact sealings, e.g. of labyrinth type using sealing fluid, e.g. steam
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
- F01D11/02—Preventing or minimising internal leakage of working-fluid, e.g. between stages by non-contact sealings, e.g. of labyrinth type
- F01D11/04—Preventing or minimising internal leakage of working-fluid, e.g. between stages by non-contact sealings, e.g. of labyrinth type using sealing fluid, e.g. steam
- F01D11/06—Control thereof
Abstract
The invention provides a shutdown method of a shaft seal steam turbine, which belongs to the field of combined cycle power generation of a gas turbine and a steam turbine, and comprises the steps of sequentially closing a reheating main steam electric valve at a furnace side, closing a medium-pressure steam drum to the reheating main steam electric valve, closing a low-pressure main steam electric valve at the furnace side, closing a main steam pipeline drain valve at the turbine side, manually adjusting a high-pressure bypass valve, controlling the pressure behind the valve to be not more than 3MPa, simultaneously controlling a shaft seal steam overflow valve to be released manually, reducing the opening of the shaft seal overflow valve as much as possible, preventing shaft seal steam from being discharged to a condenser through the shaft seal overflow valve, and reducing the flow of the shaft seal steam. Stopping supplying shaft seal steam after the steam turbine is vacuumized to zero; and closing an electric door of a channel from cold reheat steam to medium pressure auxiliary steam, stopping supplying the medium pressure auxiliary steam, and opening a drain valve of a medium pressure auxiliary steam header to finish shutdown operation. The invention solves the problem that the existing shutdown mode adopts external steam to cause steam outage.
Description
Technical Field
The invention belongs to the field of combined cycle power generation of a gas turbine and a steam turbine, and particularly relates to a method for stopping a shaft seal steam turbine.
Background
During normal operation of the unit, the medium-pressure auxiliary steam is used as a standby steam source for supplying steam by a shaft seal, the source is taken from cold reheat steam of the waste heat boiler, the shaft seal of the steam turbine is self-sealing, and the steam source is from steam leakage of a high-pressure cylinder of the steam turbine and steam leakage of a valve rod of a main steam valve. When the unit is ready to stop running, the steam source of the medium-pressure auxiliary steam system is switched from cold reheat steam to outsourcing steam, and during the load reduction period of the unit, when the self-sealing steam source parameter of the turbine shaft seal is insufficient to provide normal running of the shaft seal system, auxiliary steam is put into the shaft seal steam for supplying steam so as to ensure the normal running of the shaft seal system, therefore, until the generator is disconnected, after the turbine is inerted to the rotating speed of 0rpm, the vacuum of the turbine is destroyed after the turbine is put into a turbine jigger, and the shaft seal steam is removed.
At present, in the shutdown process of a steam turbine in a gas turbine-steam turbine combined cycle unit, self-sealing steam parameters are insufficient to meet the requirement of shaft seal steam supply, so that shaft seal steam needs to be supplied by external steam, however, the external steam has the problem of steam outage caused by various uncontrollable factors, and after the external steam (outsourcing steam) is outage, if the steam for ensuring the normal shutdown of the steam turbine cannot be provided, the steam turbine must be subjected to vacuum breaking shutdown, the stress of metal of the steam turbine can be increased, and finally the service life of the steam turbine is influenced.
Disclosure of Invention
The invention provides a method for stopping a shaft seal steam turbine, which aims to solve the problem that the existing stopping mode adopts external steam to cause steam to be supplied and can not be stopped normally.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a method of shutting down a shaft seal steam turbine comprising the steps of:
s1: switching the high-pressure bypass regulating valve and the medium-pressure bypass regulating valve into manual control;
s2: closing the medium-pressure bypass regulating valve, and simultaneously controlling the pressure of cold reheat steam by regulating the high-pressure bypass regulating valve;
s3: closing the drain valve of the turbine body, and the high-pressure main steam drain valve, the reheat main steam drain valve and the cold reheat steam drain valve before the turbine; closing a drain valve of a high-pressure system of the waste heat boiler, a drain valve of a reheating system of the waste heat boiler and a drain valve of a cold reheating system of the waste heat boiler simultaneously;
s4: closing an electric door between the medium-pressure auxiliary steam channel and the IGCC air separation system and an electric door from the medium-pressure auxiliary steam channel to the gasification steam supply channel;
s5: stopping the medium-pressure steam drum of the waste heat boiler to collect steam;
s6: closing an electric valve, a valve regulating valve and a temperature reducing water hand valve of a low-pressure main steam-low-pressure auxiliary steam channel, and simultaneously opening a drain valve of a low-pressure auxiliary steam header;
s7: closing an electric valve of a channel from medium-pressure main steam to cold reheat steam at the furnace side of the waste heat boiler and an electric valve of a channel from low-pressure main steam at the furnace side of the waste heat boiler;
s8: closing a valve for reducing the temperature water of the high-pressure main steam at the furnace side of the waste heat boiler and reheating the main steam;
s9: switching the turbine shaft seal overflow valve to manual control, and closing the shaft seal overflow valve;
s10: controlling the pressure of the shaft seal steam, and stopping supplying the shaft seal steam to reduce the temperature water;
s11: adding high-pressure bypass desuperheating water and controlling the temperature after the valve of the high-pressure bypass regulating valve;
s12: regulating the high-pressure bypass regulating valve and controlling the pressure behind the valve;
s13: executing vacuum breaking and shaft seal withdrawing operation;
s14: closing a high-pressure main steam electric valve of the waste heat boiler, and simultaneously closing electric doors of a high-pressure main path and a high-pressure bypass;
s15: stopping the shaft seal steam supply;
s16: and closing an electric door of a channel from cold reheat steam to medium pressure auxiliary steam, stopping supplying the medium pressure auxiliary steam, and opening a drain valve of a medium pressure auxiliary steam header to finish shutdown operation.
Further, the medium-pressure auxiliary steam is supplied by the gas turbine-steam turbine unit through cold reheat steam.
Further, in S1, the switching of the high-pressure bypass valve and the medium-pressure bypass valve to the manual control specifically includes: after the gas turbine generator and the steam turbine generator are disconnected, the high-pressure bypass regulating valve and the medium-pressure bypass regulating valve are switched to be manually controlled.
Further, in S2, the cold reheat steam pressure is not greater than 3MPa.
Further, in S10, the control shaft seal steam pressure is 18KPa to 25KPa.
Further, in S11, the post-valve temperature of the control high-pressure bypass valve is 400 ℃.
Further, in S12, the valve post pressure of the control high-pressure bypass valve is not less than 2MPa.
Further, in S13, the performing a vacuum breaking and shaft retracting operation specifically includes: and executing vacuum breaking and shaft seal withdrawing operation when the disconnection time of the gas turbine generator and the turbine generator reaches 2 hours.
Further, in S14, the closing of the high-pressure main steam electric valve of the exhaust-heat boiler specifically includes: and when the vacuum pressure of the steam turbine is-10 KPa, closing the high-pressure main steam electric valve of the waste heat boiler.
Further, in S15, the condition for stopping the shaft seal steam supply is that the vacuum degree of the steam turbine is zero.
Compared with the prior art, the invention has the following beneficial effects:
the invention provides a method for stopping a shaft seal steam turbine, which prevents steam from being discharged to a condenser through a drain valve by closing a medium-pressure bypass valve, a high-pressure system drain valve, a reheating system drain valve and a cold reheating system drain valve, ensures that all steam generated by heat accumulation of a waste heat boiler is used for shaft seal steam, and simultaneously utilizes the high-pressure bypass valve to control the steam pressure of a cold reheating steam pipeline, and ensures that the pressure and the temperature of the cold reheating steam pipeline meet operation requirements. The invention reduces the use of outsourcing steam, changes the situation that the steam is subject to people, improves the reliability of the unit, ensures that the steam turbine can be normally stopped under the condition of external steam outage, and avoids the problem of the increase of the stress of the steam turbine caused by vacuum breaking and stopping.
Furthermore, the invention controls the steam pressure of the shaft seal to be between 18KPa and 25KPa, and tenderness can ensure the normal pressure of the shaft seal.
Furthermore, according to the invention, when the separation time of the gas turbine generator and the turbine generator reaches 2 hours, the vacuum breaking and shaft seal withdrawing operation is performed, so that the turbine can be ensured to have operating conditions.
Drawings
FIG. 1 is a schematic diagram of a steam turbine shaft seal system;
FIG. 2 is a schematic view of a combined cycle steam turbine-steam turbine system.
Detailed Description
In order that those skilled in the art may better understand the present invention, a further detailed description of the technical solution of the present invention will be provided with reference to the accompanying drawings, which are intended to illustrate, but not to limit, the present invention.
It should be noted that the terms "comprises" and "comprising," and any variations thereof, in the description and claims of the present invention are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements that are expressly listed or inherent to such process, method, system, article, or apparatus.
The shaft seal steam should select a steam supply source according to the cylinder temperature so as to match the steam supply temperature with the metal temperature. From the aspect of parameters, the pressure of a shaft seal system of the steam turbine needs to be maintained between 22KPa and 25KPa, the steam supply temperature of the shaft seal is more than 280 ℃, and after the gas turbine generator and the steam turbine generator are separated, the pressure of a high-pressure system of the waste heat boiler is 5.4MPa, the temperature is 490 ℃, the pressure of a reheating system is 2.4MPa, and the temperature is 490 ℃, so that the steam supply requirement of the shaft seal is completely met from the initial steam parameters.
As shown in fig. 1 and 2, from the aspect of a circulation system, the high-pressure main steam of the waste heat boiler is supplied to the front of the high-pressure main steam valve of the steam turbine through a high-pressure bypass regulating valve, and is connected with a cold reheat steam pipeline, and after the steam turbine is switched on and the main steam valve is closed, the high-pressure main steam is supplied to the cold reheat steam pipeline through the high-pressure bypass regulating valve; the cold reheat steam pipe supplies steam to the medium pressure auxiliary steam header, and then the medium pressure auxiliary steam header supplies steam to the shaft seal system. It can be seen that it is entirely feasible from a system architecture; in terms of operation, after the gas turbine and the steam turbine are opened and stopped, the furnace side high-pressure main steam electric valve is not closed, the intermediate-temperature and cold re-supply steam electric valve, the furnace side reheating main steam electric valve, the high-pressure and intermediate-pressure system steam turbine side drain valve and the boiler side drain valve are closed at the same time, so that all steam generated by heat accumulation of the waste heat boiler is used for shaft seal steam, and meanwhile, the high-side regulating valve is used for controlling the steam pressure of the cold reheating steam pipeline, so that the pressure and the temperature of the cold reheating steam pipeline meet the operation requirements.
Example 1
The invention provides a method for stopping a shaft seal steam turbine, which comprises the following steps:
(1) Confirming that the medium-pressure auxiliary steam is supplied by the self-produced cold reheat steam of the gas turbine-steam turbine unit;
(2) After the gas turbine generator and the turbine generator are disconnected, switching the high-pressure bypass regulating valve and the medium-pressure bypass regulating valve from automatic control to manual control;
(3) Manually closing a middle-pressure bypass regulating valve of the steam turbine to prevent the cold re-steam from being discharged into the condenser through the middle-pressure bypass, and manually regulating a high-pressure bypass regulating valve to control the pressure of the cold re-steam not to exceed the rated pressure of 3MPa;
(4) Closing the steam turbine body drain valve, and the high-pressure main steam drain valve, the reheat main steam drain valve and the cold reheat steam drain valve before the steam turbine, so as to prevent steam from being discharged to the condenser through the drain valve;
(5) Closing a drain valve of a high-pressure system of the waste heat boiler, a drain valve of a reheating system of the waste heat boiler and a drain valve of a cold reheating system of the waste heat boiler, and preventing steam from being discharged to an industrial waste water pipeline through the drain valve;
(6) Closing an electric door from the medium-pressure auxiliary steam to the IGCC air separation system and an electric door from the medium-pressure auxiliary steam channel to the gasification steam supply channel, wherein the gasification medium-pressure steam is not reversely connected with the medium-pressure auxiliary steam header;
(7) Exiting the medium-pressure steam drum to collect steam, and preventing cold re-steam from reversely stringing to other systems through a medium-pressure steam drum steam collecting pipeline;
(8) Closing the low-pressure main steam to low-pressure auxiliary steam electric valve, the valve regulating valve and the temperature reducing water hand valve, and opening the drain valve of the low-pressure auxiliary steam header;
(9) Closing an electric valve of a channel from medium-pressure main steam to cold reheat steam at the furnace side of the waste heat boiler and an electric valve of a channel from low-pressure main steam at the furnace side of the waste heat boiler, and maintaining pressure of steam in the system;
(10) The high-pressure main steam desuperheating water and the reheat main steam desuperheating water at the side of the waste heat boiler are withdrawn, the hand valve is closed, and the steam parameters are prevented from being reduced by the leaked desuperheating water in the hand valve entering the system;
(11) Switching the control mode of the shaft seal overflow valve of the steam turbine to manual control, and manually closing the shaft seal overflow valve to prevent the shaft seal steam from being discharged to the steam condenser through the overflow valve to cause steam loss;
(12) Controlling the steam pressure of the shaft seal to be between 18KPa, and ensuring the normal pressure of the shaft seal;
(13) The seal steam temperature reducing water is withdrawn, so that the seal water is prevented from being carried by the seal water due to the fact that the temperature reducing water leaks into the system;
(14) Adding high-pressure bypass desuperheating water to prevent the pipeline behind the valve from overtemperature, and controlling the temperature behind the valve of the high-pressure bypass regulating valve to be 400 ℃ through desuperheating water;
(15) The high-pressure bypass regulating valve is manually regulated along with the reduction of the steam pressure before the high-pressure bypass, and the pressure after the high-pressure bypass regulating valve is controlled to be not lower than 2MPa;
(16) After the gas turbine generator and the turbine generator are separated for 2 hours, when the turbine has vacuum breaking and shaft seal withdrawing conditions, executing vacuum breaking and shaft seal withdrawing operation;
(17) When the vacuum of the steam turbine is reduced to-10 kPa, remotely closing the high-pressure main steam electric valve of the waste heat boiler, and manually immediately and immediately carrying out on-site electric doors of the high-pressure main way and the high-pressure bypass;
(18) After the vacuum reaches zero, the shaft seal steam is withdrawn;
(19) Closing an electric door of the channel from the cold reheat steam to the medium pressure auxiliary steam, exiting the medium pressure auxiliary steam, opening a header for draining water, and ending the shutdown operation.
Example two
(1) Confirming that the medium-pressure auxiliary steam is supplied by the self-produced cold reheat steam of the gas turbine-steam turbine unit;
(2) After the gas turbine generator and the turbine generator are disconnected, switching the high-pressure bypass regulating valve and the medium-pressure bypass regulating valve from automatic control to manual control;
(3) Manually closing a middle-pressure bypass regulating valve of the steam turbine to prevent the cold re-steam from being discharged into the condenser through the middle-pressure bypass, and manually regulating a high-pressure bypass regulating valve to control the pressure of the cold re-steam not to exceed the rated pressure of 3MPa;
(4) Closing the steam turbine body drain valve, and the high-pressure main steam drain valve, the reheat main steam drain valve and the cold reheat steam drain valve before the steam turbine, so as to prevent steam from being discharged to the condenser through the drain valve;
(5) Closing a drain valve of a high-pressure system of the waste heat boiler, a drain valve of a reheating system of the waste heat boiler and a drain valve of a cold reheating system of the waste heat boiler, and preventing steam from being discharged to an industrial waste water pipeline through the drain valve;
(6) Closing an electric door from the medium-pressure auxiliary steam to the IGCC air separation system and an electric door from the medium-pressure auxiliary steam channel to the gasification steam supply channel, wherein the gasification medium-pressure steam is not reversely connected with the medium-pressure auxiliary steam header;
(7) Exiting the medium-pressure steam drum to collect steam, and preventing cold re-steam from reversely stringing to other systems through a medium-pressure steam drum steam collecting pipeline;
(8) Closing the low-pressure main steam to low-pressure auxiliary steam electric valve, the valve regulating valve and the temperature reducing water hand valve, and opening the drain valve of the low-pressure auxiliary steam header;
(9) Closing an electric valve of a channel from medium-pressure main steam to cold reheat steam at the furnace side of the waste heat boiler and an electric valve of a channel from low-pressure main steam at the furnace side of the waste heat boiler, and maintaining pressure of steam in the system;
(10) The high-pressure main steam desuperheating water and the reheat main steam desuperheating water at the side of the waste heat boiler are withdrawn, the hand valve is closed, and the steam parameters are prevented from being reduced by the leaked desuperheating water in the hand valve entering the system;
(11) Switching the control mode of the shaft seal overflow valve of the steam turbine to manual control, and manually closing the shaft seal overflow valve to prevent the shaft seal steam from being discharged to the steam condenser through the overflow valve to cause steam loss;
(12) Controlling the steam pressure of the shaft seal to be between 25KPa, and ensuring the normal pressure of the shaft seal;
(13) The seal steam temperature reducing water is withdrawn, so that the seal water is prevented from being carried by the seal water due to the fact that the temperature reducing water leaks into the system;
(14) Adding high-pressure bypass desuperheating water to prevent the pipeline behind the valve from overtemperature, and controlling the temperature behind the valve of the high-pressure bypass regulating valve to be 400 ℃ through desuperheating water;
(15) The high-pressure bypass regulating valve is manually regulated along with the reduction of the steam pressure before the high-pressure bypass, and the pressure after the high-pressure bypass regulating valve is controlled to be not lower than 2MPa;
(16) After the gas turbine generator and the turbine generator are separated for 2 hours, when the turbine has vacuum breaking and shaft seal withdrawing conditions, executing vacuum breaking and shaft seal withdrawing operation;
(17) When the vacuum of the steam turbine is reduced to-10 kPa, remotely closing the high-pressure main steam electric valve of the waste heat boiler, and manually immediately and immediately carrying out on-site electric doors of the high-pressure main way and the high-pressure bypass;
(18) After the vacuum reaches zero, the shaft seal steam is withdrawn;
(19) Closing an electric door of the channel from the cold reheat steam to the medium pressure auxiliary steam, exiting the medium pressure auxiliary steam, opening a header for draining water, and ending the shutdown operation.
Example III
(1) Confirming that the medium-pressure auxiliary steam is supplied by the self-produced cold reheat steam of the gas turbine-steam turbine unit;
(2) After the gas turbine generator and the turbine generator are disconnected, switching the high-pressure bypass regulating valve and the medium-pressure bypass regulating valve from automatic control to manual control;
(3) Manually closing a middle-pressure bypass regulating valve of the steam turbine to prevent the cold re-steam from being discharged into the condenser through the middle-pressure bypass, and manually regulating a high-pressure bypass regulating valve to control the pressure of the cold re-steam not to exceed the rated pressure of 3MPa;
(4) Closing the steam turbine body drain valve, and the high-pressure main steam drain valve, the reheat main steam drain valve and the cold reheat steam drain valve before the steam turbine, so as to prevent steam from being discharged to the condenser through the drain valve;
(5) Closing a drain valve of a high-pressure system of the waste heat boiler, a drain valve of a reheating system of the waste heat boiler and a drain valve of a cold reheating system of the waste heat boiler, and preventing steam from being discharged to an industrial waste water pipeline through the drain valve;
(6) Closing an electric door from the medium-pressure auxiliary steam to the IGCC air separation system and an electric door from the medium-pressure auxiliary steam channel to the gasification steam supply channel, wherein the gasification medium-pressure steam is not reversely connected with the medium-pressure auxiliary steam header;
(7) Exiting the medium-pressure steam drum to collect steam, and preventing cold re-steam from reversely stringing to other systems through a medium-pressure steam drum steam collecting pipeline;
(8) Closing the low-pressure main steam to low-pressure auxiliary steam electric valve, the valve regulating valve and the temperature reducing water hand valve, and opening the drain valve of the low-pressure auxiliary steam header;
(9) Closing an electric valve of a channel from medium-pressure main steam to cold reheat steam at the furnace side of the waste heat boiler and an electric valve of a channel from low-pressure main steam at the furnace side of the waste heat boiler, and maintaining pressure of steam in the system;
(10) The high-pressure main steam desuperheating water and the reheat main steam desuperheating water at the side of the waste heat boiler are withdrawn, the hand valve is closed, and the steam parameters are prevented from being reduced by the leaked desuperheating water in the hand valve entering the system;
(11) Switching the control mode of the shaft seal overflow valve of the steam turbine to manual control, and manually closing the shaft seal overflow valve to prevent the shaft seal steam from being discharged to the steam condenser through the overflow valve to cause steam loss;
(12) Controlling the shaft seal steam pressure between 22KPa, and ensuring the normal shaft seal pressure;
(13) The seal steam temperature reducing water is withdrawn, so that the seal water is prevented from being carried by the seal water due to the fact that the temperature reducing water leaks into the system;
(14) Adding high-pressure bypass desuperheating water to prevent the pipeline behind the valve from overtemperature, and controlling the temperature behind the valve of the high-pressure bypass regulating valve to be 400 ℃ through desuperheating water;
(15) The high-pressure bypass regulating valve is manually regulated along with the reduction of the steam pressure before the high-pressure bypass, and the pressure after the high-pressure bypass regulating valve is controlled to be not lower than 2MPa;
(16) After the gas turbine generator and the turbine generator are separated for 2 hours, when the turbine has vacuum breaking and shaft seal withdrawing conditions, executing vacuum breaking and shaft seal withdrawing operation;
(17) When the vacuum of the steam turbine is reduced to-10 kPa, remotely closing the high-pressure main steam electric valve of the waste heat boiler, and manually immediately and immediately carrying out on-site electric doors of the high-pressure main way and the high-pressure bypass;
(18) After the vacuum reaches zero, the shaft seal steam is withdrawn;
(19) Closing an electric door of the channel from the cold reheat steam to the medium pressure auxiliary steam, exiting the medium pressure auxiliary steam, opening a header for draining water, and ending the shutdown operation.
It will be appreciated by those skilled in the art that the invention can be practiced in other embodiments that depart from the spirit or essential characteristics thereof. Accordingly, the above disclosed embodiments are illustrative in all respects only and not restrictive, and all changes coming within the meaning and equivalency range of the invention are intended to be embraced therein.
Claims (10)
1. A method of shutting down a shaft seal steam turbine comprising the steps of:
s1: switching the high-pressure bypass regulating valve and the medium-pressure bypass regulating valve into manual control;
s2: closing the medium-pressure bypass regulating valve, and simultaneously controlling the pressure of cold reheat steam by regulating the high-pressure bypass regulating valve;
s3: closing the drain valve of the turbine body, and the high-pressure main steam drain valve, the reheat main steam drain valve and the cold reheat steam drain valve before the turbine; closing a drain valve of a high-pressure system of the waste heat boiler, a drain valve of a reheating system of the waste heat boiler and a drain valve of a cold reheating system of the waste heat boiler simultaneously;
s4: closing an electric door between the medium-pressure auxiliary steam channel and the IGCC air separation system and an electric door from the medium-pressure auxiliary steam channel to the gasification steam supply channel;
s5: stopping the medium-pressure steam drum of the waste heat boiler to collect steam;
s6: closing an electric valve, a valve regulating valve and a temperature reducing water hand valve of a low-pressure main steam-low-pressure auxiliary steam channel, and simultaneously opening a drain valve of a low-pressure auxiliary steam header;
s7: closing an electric valve of a channel from medium-pressure main steam to cold reheat steam at the furnace side of the waste heat boiler and an electric valve of a channel from low-pressure main steam at the furnace side of the waste heat boiler;
s8: closing a valve for reducing the temperature water of the high-pressure main steam at the furnace side of the waste heat boiler and reheating the main steam;
s9: switching the turbine shaft seal overflow valve to manual control, and closing the shaft seal overflow valve;
s10: controlling the pressure of the shaft seal steam, and stopping supplying the shaft seal steam to reduce the temperature water;
s11: adding high-pressure bypass desuperheating water and controlling the temperature after the valve of the high-pressure bypass regulating valve;
s12: regulating the high-pressure bypass regulating valve and controlling the pressure behind the valve;
s13: executing vacuum breaking and shaft seal withdrawing operation;
s14: closing a high-pressure main steam electric valve of the waste heat boiler, and simultaneously closing electric doors of a high-pressure main path and a high-pressure bypass;
s15: stopping the shaft seal steam supply;
s16: and closing an electric door of a channel from cold reheat steam to medium pressure auxiliary steam, stopping supplying the medium pressure auxiliary steam, and opening a drain valve of a medium pressure auxiliary steam header to finish shutdown operation.
2. The method of shutting down a shaft seal steam turbine according to claim 1, wherein said intermediate pressure auxiliary steam is supplied by a gas turbine-turbine unit via cold reheat steam.
3. The method for stopping a shaft seal steam turbine according to claim 1, wherein in S1, the switching of the high-pressure bypass valve and the medium-pressure bypass valve to manual control is specifically: after the gas turbine generator and the steam turbine generator are disconnected, the high-pressure bypass regulating valve and the medium-pressure bypass regulating valve are switched to be manually controlled.
4. The method of shutting down a shaft seal steam turbine according to claim 1, wherein in S2, the cold reheat steam pressure is no greater than 3MPa.
5. The method of shutting down a shaft seal steam turbine according to claim 1, wherein in S10, the shaft seal steam pressure is controlled to be 18KPa to 25KPa.
6. The method of shutting down a shaft seal steam turbine according to claim 1, wherein in S11, the control high pressure bypass valve is controlled to have a post valve temperature of 400 ℃.
7. The method of shutting down a shaft seal steam turbine according to claim 1, wherein in S12, the control high pressure bypass valve has a post-valve pressure of not less than 2MPa.
8. The method according to claim 1, wherein in S13, the performing the vacuum breaking and the seal removing operations is specifically: and executing vacuum breaking and shaft seal withdrawing operation when the disconnection time of the gas turbine generator and the turbine generator reaches 2 hours.
9. The method for stopping a shaft seal steam turbine according to claim 1, wherein in S14, the closing of the high-pressure main steam electric valve of the waste heat boiler specifically comprises: and when the vacuum pressure of the steam turbine is-10 KPa, closing the high-pressure main steam electric valve of the waste heat boiler.
10. The method of stopping a shaft seal steam turbine according to claim 1, wherein in S15, the condition for stopping the supply of shaft seal steam is zero vacuum of the turbine.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311481898.4A CN117418909A (en) | 2023-11-08 | 2023-11-08 | Method for stopping shaft seal steam turbine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311481898.4A CN117418909A (en) | 2023-11-08 | 2023-11-08 | Method for stopping shaft seal steam turbine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117418909A true CN117418909A (en) | 2024-01-19 |
Family
ID=89522763
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311481898.4A Pending CN117418909A (en) | 2023-11-08 | 2023-11-08 | Method for stopping shaft seal steam turbine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117418909A (en) |
-
2023
- 2023-11-08 CN CN202311481898.4A patent/CN117418909A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109441575B (en) | Method for operating heat supply network system of steam combined cycle generator set in heat supply period | |
| CN110131003B (en) | System and method for starting and stopping two loops of high-temperature gas cooled reactor nuclear power unit | |
| CN107120149B (en) | The method and system of newly-built supercritical unit is debugged using external activated vapor | |
| CN108757068B (en) | Combined cycle steam turbine set total cut heat supply control method and device | |
| CN108425706B (en) | Shaft seal steam supply system for secondary reheating unit and control method of shaft seal steam supply system | |
| CN206055732U (en) | A kind of new heat-supplying unit | |
| CN111255536B (en) | FCB operation method of gas-steam unit power plant | |
| CN107664045B (en) | High-temperature gas cooled reactor steam turbine gland seal steam supply system and method | |
| CN207245763U (en) | A kind of high temperature gas cooled reactor Turbine Steam gland sealing steam supply system | |
| CN110425011B (en) | Optimal control method for shaft seal and door rod steam leakage system of power station steam turbine unit | |
| CN113404551A (en) | Shaft seal steam supply system of gas-steam combined cycle heat supply unit and operation method | |
| CN112879107A (en) | Shaft seal auxiliary steam source heat standby device and control method thereof | |
| CN108691579A (en) | Without the startup method for starting steam after a kind of tripping of thermal power plant's generating set | |
| CN117418909A (en) | Method for stopping shaft seal steam turbine | |
| CN112360580A (en) | Rapid cooling mode for steam turbine after shutdown by using waste heat of boiler | |
| CN111911252B (en) | Supercritical heat supply unit and cold starting method thereof | |
| CN212054843U (en) | Automatic start-stop control system of gas-steam combined cycle unit | |
| CN110925036B (en) | Low-pressure cylinder flexible output cooling system under steam extraction heat supply working condition and operation method thereof | |
| CN114109527A (en) | Steam turbine adjusting method without pre-starting valve for realizing high-medium pressure combined start | |
| CN217584390U (en) | High temperature gas cooled reactor steam recovery system | |
| CN219317016U (en) | Auxiliary condensate pump equipment for saving energy of turbine condensate system | |
| CN112648022A (en) | Method for preventing turbo generator set from seriously overspeed | |
| CN113530613B (en) | Control method after gas loss of conventional island of nuclear power plant | |
| CN219548930U (en) | Main steam point steam source system for pressurized water reactor nuclear generator set | |
| CN114112411A (en) | Steam turbine shaft seal system state monitoring system and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |