Steam cooling device of steam turbine generator unit
By using a steam matching device and a return pipe in the steam turbine generator set to mix, cool, and preheat the third-stage extraction steam with the second-stage extraction steam, the problem of fracture caused by excessive temperature of the third-stage extraction steam was solved, achieving the effects of energy saving and cost reduction.
Patent Information
- Application Number
- CN202423048545.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2025-12-05
- Estimated Expiration
- 2034-12-11
AI Technical Summary
The temperature of the third-stage extraction steam of the 350MW steam turbine generator unit exceeded the design standard, which made the connection between the heat exchange tube and the tube sheet prone to breakage. At the same time, the second-stage extraction steam needs to be reheated before use, resulting in heat waste and increased energy consumption.
A steam matching device and a return pipe are used to mix and cool the third-stage extraction steam with the second-stage extraction steam. The hot steam after the third-stage high-pressure heater is used to preheat the second-stage extraction steam through the return pipe, which avoids breakage and saves energy.
It effectively prevents breakage at the connection between heat exchange tubes and tube sheets, reduces production costs, saves energy, and improves energy efficiency by using the heat from the third-stage extraction steam to preheat the second-stage extraction steam.
Smart Images
Figure CN223636151U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to steam turbine generator technology field, concretely is a steam turbine generator unit steam cooling device. BACKGROUND
[0002] On the one hand, the three-stage extraction steam of 350MW steam turbine generator unit is extracted from the 13th stage of the intermediate pressure cylinder at 1.623MPa pressure and 434.6℃ temperature to supply the three-stage high pressure heater, since the shell side design pressure / tolerance test of the three-stage high pressure heater is 2.1Mpa / 3Mpa and the design temperature is 450℃, the tube side design pressure / tolerance test is 31.2Mpa / 39Mpa and the design temperature is 250℃, and the three-stage extraction steam temperature during the operation of 350MW steam turbine generator unit is 446-451℃, which has exceeded the three-stage extraction steam design standard temperature, therefore, during the equipment operation, the water side and the steam side exist pressure difference: 17-20Mpa and temperature difference: about 200℃, during the unit start-stop process, the heat exchange tube bundle in the three-stage high pressure heater is affected by internal feed water pressure impact force, tube bundle external thermal stress and tube plate stress change, and the welding seam or expansion joint of the heat exchange tube and the tube plate is prone to tensile fracture, resulting in heat exchange tube leakage; on the other hand, the two-stage extraction steam extracts a part of low temperature steam, and the low temperature steam needs to be heated by the two-stage high pressure heater before being used again, resulting in large energy consumption of the two-stage high pressure heater.
[0003] In summary, on the one hand, the heat extracted by the three-stage extraction steam is wasted, and the welding seam or expansion joint of the heat exchange tube and the tube plate is prone to tensile fracture, and on the other hand, the steam extracted by the two-stage extraction steam needs to be heated by the separately arranged two-stage high pressure heater before being used again, if the heat in the three-stage extraction steam is used to preheat the two-stage extraction steam, the two-stage extraction steam enters the two-stage high pressure heater after preheating, which is of great significance to energy saving and cost reduction. UTILITY MODEL CONTENT
[0004] The utility model discloses to the above-mentioned insufficient, provide a kind of steam turbine generator unit steam cooling device, can the heat in the three-stage extraction steam be used to preheat two-stage extraction steam, the two-stage extraction steam enters two-stage high pressure heater after preheating, both energy saving, also can reduce production cost.
[0005] In order to achieve the above object, the utility model adopts the following technical scheme:
[0006] The utility model relates to a steam turbine generator set steam cooling device, including three section high pressure heater and two section high pressure heater, the three section steam inlet pipe of connecting in three section high pressure heater air inlet end, the three section steam outlet pipe of connecting in three section high pressure heater air outlet end, the two section steam inlet pipe of connecting in two section high pressure heater air inlet end, the three section medium pressure steam pipe of connecting in three section medium pressure cylinder air outlet end, its characterized in that: steam adapter one, the air inlet end of steam adapter one communicates three section medium pressure steam pipe and two section steam extraction pipe, the air outlet end of steam adapter one communicates with three section steam inlet pipe's air inlet end, the three section steam outlet pipe is provided with backflow pipe, and the backflow pipe communicates with two section steam inlet pipe.
[0007] Further, the two section steam inlet pipe is provided with a steam adapter two, the air inlet end of the steam adapter two communicates with the two section steam extraction pipe and the backflow pipe, and the air outlet end of the steam adapter two communicates with the two section high pressure heater.
[0008] Further, the three section steam outlet pipe is provided with an oxygen remover.
[0009] Further, the backflow pipe is provided with a one-way valve one and a flow limiting valve.
[0010] Further, the three section medium pressure steam pipe and the two section steam extraction pipe are respectively provided with a one-way valve two and a one-way valve three.
[0011] The utility model has the advantages of:
[0012] In practical application, the hot steam extracted by the three section steam extraction and the cold steam extracted by the two section steam extraction are introduced into the steam adapter one through the three section medium pressure steam pipe and the two section steam extraction pipe, the steam is mixed and cooled in the steam adapter one and the three section steam inlet pipe, and the cooled steam enters the three section high pressure heater, so that the welding seam or the expanded joint between the heat exchange pipe and the tube plate in the three section high pressure heater is prevented from being easily stretched and broken; part of the hot steam after the three section high pressure heater returns to the two section steam inlet pipe through the backflow pipe, the hot steam is mixed with the cold steam in the two section steam inlet pipe, the cold steam is preheated, and the preheated cold steam enters the two section high pressure heater, so that energy is saved and production cost is reduced; the heat in the steam extracted by the three section steam extraction is used for preheating the two section steam, the preheated two section steam enters the two section high pressure heater, so that energy is saved and production cost is reduced. BRIEF DESCRIPTION OF DRAWINGS
[0013] Figure 1 It is the whole structure schematic diagram of the utility model;
[0014] Mark: three section high pressure heater 1;Three section steam inlet pipe 11;Three section steam outlet pipe 12;Two section high pressure heater 2;Two section steam inlet pipe 21;Three section medium pressure steam pipe 3;Steam adapter one 4;Two section steam extraction pipe 5;Backflow pipe 6;Steam adapter two 7;Oxygen remover 8. DETAILED DESCRIPTION
[0015] As Figure 1 shown, a steam turbine generator set steam cooling device, including three high pressure heater 1 and two high pressure heater 2, connected to the three high pressure heater 1 inlet end of three stage steam pipe 11, connected to the three high pressure heater 1 outlet end of three stage steam pipe 12, connected to the two high pressure heater 2 inlet end of two stage steam pipe 21, connected to the three stage medium pressure cylinder outlet end of three stage medium pressure steam pipe 3, characterized by: steam matching device one 4, the inlet end of the steam matching device one 4 communicates three stage medium pressure steam pipe 3 and two stage extraction pipe 5, the outlet end of the steam matching device one 4 communicates with the inlet end of three stage steam pipe 11, the three stage steam pipe 12 is provided with backflow pipe 6, the backflow pipe 6 communicates with two stage steam pipe 21.
[0016] In use, the hot steam extracted by the three stage extraction and the cold steam extracted by the two stage extraction are introduced into the steam matching device one 4 through the three stage medium pressure steam pipe 3 and the two stage extraction pipe 5, and the steam is mixed and cooled in the steam matching device one 4 and the three stage steam pipe 11, and then the cooled steam enters the three high pressure heater 1, which effectively prevents the weld or expanded joint between the heat exchange pipe and the tube plate in the three high pressure heater 1 from being easily stretched and broken; part of the hot steam after the three high pressure heater 1 returns to the two stage steam pipe 21 through the backflow pipe 6, mixes with the cold steam in the two stage steam pipe 21, preheats the cold steam, and then the preheated cold steam enters the two high pressure heater 2, which not only saves energy but also reduces production cost; the heat in the steam extracted by the three stage extraction is used to preheat the two stage extraction, so that the two stage extraction enters the two high pressure heater 2 after being preheated, which not only saves energy but also reduces production cost.
[0017] As Figure 1 shown, the two stage steam pipe 21 is provided with a steam matching device two 7, the inlet end of the steam matching device two 7 communicates the two stage extraction pipe 5 and the backflow pipe 6, and the outlet end of the steam matching device two 7 communicates the two high pressure heater 2; in this embodiment, the cold steam and the hot steam can be mixed more uniformly through the steam matching device two 7, and the preheating effect is better.
[0018] As Figure 1 shown, the three stage steam pipe 12 is provided with a deaerator 8; in this embodiment, the non-condensed gas in the hot steam can be effectively removed through the deaerator 8.
[0019] As Figure 1 shown, the backflow pipe 6 is provided with a one-way valve one and a flow limiting valve; in this embodiment, the one-way valve one and the flow limiting valve can prevent the cold steam from flowing back.
[0020] As Figure 1As shown, the three-section medium-pressure steam pipe 3 and the two-section extraction steam pipe 5 are respectively provided with a one-way valve two and a one-way valve three; in this embodiment, the one-way valve two and the one-way valve three can prevent the hot steam and the cold steam from backflowing.
[0021] The specific embodiments described herein are merely illustrative of the present application. Those skilled in the art of the present application can make various modifications or supplements to the described specific embodiments or replace them with similar ways, but will not deviate from the scope defined by the present application.
Claims
1. A steam turbine generator unit steam cooling device, comprising a three-stage high-pressure heater (1) and a two-stage high-pressure heater (2), a three-stage inlet steam pipe (11) connected to the gas inlet end of the three-stage high-pressure heater (1), a three-stage outlet steam pipe (12) connected to the gas outlet end of the three-stage high-pressure heater (1), a two-stage inlet steam pipe (21) connected to the gas inlet end of the two-stage high-pressure heater (2), and a three-stage medium-pressure steam pipe (3) connected to the gas outlet end of the three-stage medium-pressure cylinder, characterized in that: A steam adapter one (4) is communicated with the three-stage medium-pressure steam pipe (3) and the two-stage steam extraction pipe (5) at the inlet end, and communicated with the inlet end of the three-stage steam inlet pipe (11) at the outlet end; a backflow pipe (6) is arranged on the three-stage steam outlet pipe (12), and the backflow pipe (6) is communicated with the two-stage steam inlet pipe (21).
2. A steam temperature reducing device for a steam turbine generator unit according to claim 1, wherein A steam adapter two (7) is arranged on the two-stage steam inlet pipe (21), the inlet end of the steam adapter two (7) is communicated with the two-stage steam extraction pipe (5) and the backflow pipe (6), and the outlet end of the steam adapter two (7) is communicated with the two-stage high-pressure heater (2).
3. A steam temperature reducing device for a steam turbine generator unit according to claim 1, wherein An oxygen remover (8) is arranged on the three-stage steam outlet pipe (12).
4. A steam temperature reducing device for a steam turbine generator unit according to claim 1, wherein A one-way valve one and a flow limiting valve are arranged on the backflow pipe (6).
5. A steam temperature reducing device for a steam turbine generator unit according to claim 1, wherein A one-way valve two and a one-way valve three are respectively arranged on the three-stage medium-pressure steam pipe (3) and the two-stage steam extraction pipe (5).