A kind of power plant steam turbine is quickly cooled down system
Technical field
The utility model is related to steam turbine cooling technology, particularly power plant steam turbine is quickly cooled down system.
Background technology
Supercritical turbine group maximum operating temperature is up to 600 DEG C, and the heat preservation of the outside of Large-scale machine set steam turbine
Heat-insulating property is good, and in maintenance down, cylinder radiating condition is poor, and natural cooling rate is slow.For reach steam turbine go into operation maintenance item
For part, it is necessary to ensure that organism temperature is reduced to less than 150 DEG C, this process usually requires 12 days left sides under the conditions of natural cooling
The right side extends so as to cause the repair time, increases downtime, reduces unit utilization rate.In order to overcome drawbacks described above, existing skill
What art was generally cooled down using compressed air forced cooling method, when carrying out forcing functions using compressed air, scene needs standby
There is certain air compression pipe, increase compressed air dosage, while for cooling air and cylinder gold temperature is made to match, need
Increase a set of compressed air heating system, add additional investment, and heating system power consumption is big, causes power resource unrestrained
Take.
Utility model content
The purpose of this utility model is to provide a kind of power plant steam turbine and is quickly cooled down system, and it is quick to solve existing steam turbine
Cooling system needs additional compressed air heating system, adds additional investment, and adds
Hot systems power consumption is big, the problem of power resource is caused to waste.
To achieve the above object, the utility model adopts the following technical solution:A kind of power plant steam turbine is quickly cooled down system,
The compressed air system and extract system connected including turbine system and with turbine system, the compressed air system and
Extract system is connected by the water-cooling wall in boiler with turbine system;The bottom one side of the water-cooling wall passes through compressed air hose
Road is connected with the compressed air system, bottom opposite side is connected by water-cooling wall discharge pipe line and exhaust pipe and extract system
Logical, top one side is connected by water-cooling wall connecting line with turbine system.
Preferably, the water-cooling wall is the connecting pipeline being arranged circumferentially by water screen tube along boiler side walls.
Preferably, the compressed air hose road is equipped with header, and compression is equipped between the header and compressed air system
Air switching valve.
Preferably, the exhaust pipe is connected with water-cooling wall discharge pipe line and exhaust pipe is equipped with pumping switch valve.
Preferably, the water-cooling wall discharge pipe line is equipped with water-cooling wall drain valve.
Preferably, drum and superheater have been sequentially communicated on the water-cooling wall connecting line.
Preferably, the turbine system includes the high pressure cylinder being sequentially communicated on main line and condenser and connects successively
Lead to intermediate pressure cylinder and low pressure (LP) cylinder on secondary pipeline.
Preferably, the main line include air inlet pipeline section connect with water-cooling wall connecting line, connection in air inlet pipeline section and
High pressure cylinder pipeline section between condenser and the outlet pipeline section with condenser outlet;The air inlet pipeline section is equipped with air inlet pipe
Control valve;The high pressure cylinder pipeline section is equipped with high pressure cylinder and the high pressure cylinder air intake control valve for being located at high pressure cylinder inlet end and is located at
The high pressure cylinder leaving air control valve of high pressure cylinder outlet side.
Preferably, the high pressure cylinder pipeline section parallel communication of the secondary pipeline and main line;The inlet end of the secondary pipeline is equipped with
Intermediate pressure cylinder air intake control valve.
A kind of cooling means that system is quickly cooled down using the power plant steam turbine, step are:
Step 1:Water-cooling wall drain valve is opened, water in water-cooling wall is emptied.
Step 2:Water-cooling wall drain valve and air inlet pipe control valve are closed, extract system is opened, by residual moisture in water-cooling wall
It evacuates.
Step 3:Pumping switch valve is closed, compressed air system is opened, compressed air is passed through into water-cooling wall, utilizes pot
The waste heat of stove heats compressed air.
Step 4:Air inlet pipe control valve, high pressure cylinder air intake control valve and intermediate pressure cylinder air intake control valve are opened, after heating
Compressed air is passed through in high pressure cylinder, intermediate pressure cylinder and low pressure (LP) cylinder.
Step 5:The aperture of high pressure cylinder air intake control valve and intermediate pressure cylinder air intake control valve is adjusted, is compressed after control heating empty
The air inflow of gas ensures that steam turbine stablizes cooling, until steam turbine cools down completely.
The utility model has the characteristics that and advantageous effect compared with prior art:
1. the utility model heats compressed air using boiler afterheat, power consumption is small, has saved electric energy.
2. the utility model can use vacuum before being heated using boiler afterheat to compressed air using extract system
Method excludes moisture remaining in boiler water wall, ensures that not occurring the hydrophobic of phase-change heat-exchange during steam turbine is quickly cooled down asks
Topic.
3. the cooling procedure of steam turbine high-pressure cylinder, intermediate pressure cylinder and low pressure (LP) cylinder is uniformly gentle in the utility model, effectively prevent
Steam turbine in cooling procedure concentrate by thermal stress, adds the service life of steam turbine.
The utility model can be widely applied to high-temperature service and be quickly cooled down in system.
Description of the drawings
The utility model is described in more detail below in conjunction with the accompanying drawings.
Fig. 1 is the system structure diagram of the utility model.
Reference numeral:1-boiler, 2-water-cooling wall, 3-compressed air system, 4-extract system, 5-high pressure cylinder, 6-
Intermediate pressure cylinder, 7-low pressure (LP) cylinder, 8-condenser, 9-air inlet pipeline section, 10-high pressure cylinder pipeline section, 11-outlet pipeline section, 12-secondary pipe
Road, 13-air inlet pipe control valve, 14-high pressure cylinder air intake control valve, 15-high pressure cylinder leaving air control valve, the air inlet of 16-intermediate pressure cylinder
Control valve, 17-compressed air line, 18-exhaust pipe, 19-water-cooling wall discharge pipe line, 20-water-cooling wall connecting line,
21-header, 22-drum, 23-superheater, 24-air pressure switch valve, 25-pumping switch valve, the draining of 26-water-cooling wall
Valve.
Specific embodiment
Embodiment is shown in Figure 1, and a kind of power plant steam turbine is quickly cooled down system, including turbine system and and steamer
The compressed air system 3 of machine system connectivity and extract system 4, the compressed air system 3 and extract system 4 pass through in boiler 1
Water-cooling wall 2 connected with turbine system;The water-cooling wall 2 is the communicating pipe being arranged circumferentially by water screen tube along boiler side walls
Road;The bottom one side of the water-cooling wall 2 is connected by compressed air line 17 with the compressed air system 3, and the compression is empty
Air pipe 17 is equipped with header 21, and air pressure switch valve 24 is equipped between the header 21 and compressed air system 3;The water
The bottom opposite side of cold wall 2 is connected by water-cooling wall discharge pipe line 19 and exhaust pipe 18 with extract system 4, the exhaust pipe
18 connected respectively with the inlet segment of water-cooling wall discharge pipe line and water exit end by the first three-way connection and exhaust pipe be equipped with take out
Air cock;The water exit end of the water-cooling wall discharge pipe line is equipped with water-cooling wall drain valve;The top one side of the water-cooling wall 2 passes through
Water-cooling wall connecting line 20 is connected with turbine system;Drum 22 and overheat have been sequentially communicated on the water-cooling wall connecting line 20
Device 23.
The turbine system includes the high pressure cylinder 5 being sequentially communicated on main line and condenser 8 and is sequentially communicated
Intermediate pressure cylinder 6 and low pressure (LP) cylinder 7 on secondary pipeline 12;The main line include connected with water-cooling wall connecting line 20 air inlet pipeline section 9,
Connect the high pressure cylinder pipeline section 10 between air inlet pipeline section 9 and condenser 8 and the outlet pipeline section 11 with condenser outlet;Institute
Air inlet pipeline section 9 is stated equipped with air inlet pipe control valve 13;The high pressure cylinder pipeline section 10 be equipped with high pressure cylinder 5 and be located at high pressure cylinder into
The high pressure cylinder air intake control valve 14 at gas end and the high pressure cylinder leaving air control valve 15 for being located at high pressure cylinder outlet side.
10 parallel communication of high pressure cylinder pipeline section of the secondary pipeline 12 and main line;The air inlet of the secondary pipeline 12 passes through
Two three-way connections connect respectively with the air inlet pipeline section 9 of main line and high pressure cylinder pipeline section 10, gas outlet is connected with condenser;The height
Cylinder pressure 5 is single current high pressure cylinder, and intermediate pressure cylinder and low pressure (LP) cylinder are double-current high pressure cylinder;The secondary pipeline 12 includes the secondary pipe being sequentially communicated
Road air inlet pipeline section, secondary pipeline connecting pipe section and secondary pipeline outlet pipeline section;It is set on the secondary pipeline air inlet pipeline section of the secondary pipeline 12
There is intermediate pressure cylinder air intake control valve 16;The secondary pipeline air inlet pipeline section is connected with the air inlet of intermediate pressure cylinder 6, and medium pressure cylinder 6 goes out
Gas port is connected by secondary pipeline connecting pipe section with the air inlet of low pressure (LP) cylinder 7, and the gas outlet of the low pressure (LP) cylinder 7 passes through secondary pipeline outlet
Pipeline section is connected with condenser.
By taking 660MW Steam Turbines as an example, the construction procedure of the utility model is:
Step 1:Water-cooling wall drain valve 26 is opened, water in water-cooling wall 2 is emptied.
Step 2:Water-cooling wall drain valve 26 and air inlet pipe control valve 13 are closed, opens pumping switch valve 25, opens pumping system
System 4, residual moisture in water-cooling wall 2 is evacuated.
Step 3:Extract system 4 is closed, pumping switch valve 25 is closed, is then turned on air pressure switch valve 24, open pressure
Contracting air system 3 is passed through compressed air into water-cooling wall 2, is heated compressed air using the waste heat of boiler 1.
Step 4:Air inlet pipe control valve 13 is fully opened, opens high pressure cylinder air intake control valve 14 and intermediate pressure cylinder air inlet control
Compressed air after heating is passed through in high pressure cylinder 5, intermediate pressure cylinder 6 and low pressure (LP) cylinder 7 to 1/3-2/3 apertures, ensures heating by valve 16
Compressed air and the difference of high pressure cylinder temperature afterwards, when steam turbine cooldown rate is more than limit value, should close in time below 50 degree
High pressure cylinder intake valve and intermediate pressure cylinder intake valve are closed, terminate steam turbine is quickly cooled down process.
Step 5:The aperture of high pressure cylinder air intake control valve 14 and intermediate pressure cylinder air intake control valve 16 is adjusted, is pressed after control heating
The air inflow of contracting air, ensure steam turbine high pressure cylinder and intermediate pressure cylinder cooldown rate control in its own Temperature fall rate and
The half of the sum of maximum rate of temperature fall or by after heating compressed air temperature control with the temperature difference of high pressure cylinder, intermediate pressure cylinder 50
Below DEG C, until steam turbine cools down completely.