CN110567291A - Steam distribution system of air cooling island - Google Patents

Abstract

The invention provides a steam distribution system of an air-cooled island, which includes a steam exhaust pipe and a plurality of sets of steam distribution pipes connected with the exhaust pipes. Each steam distribution pipe is equipped with an airbag, and each airbag is connected with the inflatable structure and the air extraction structure respectively. The gas in the airbags is extracted, and each airbag can be pumped and shrunk to allow the corresponding steam distribution pipe to pass through. The present invention adopts the airbag instead of the isolation valve, which can effectively reduce the cost; the sealing effect formed by the abutment between the airbag and the inner wall of the steam distribution pipe after inflation is much higher than that of the isolation valve; and the normal operation of the unit can be ensured smoothly when the airbag is in a contracted state , and by controlling the inflation of the airbags separately, the start-up of the unit in winter and the smooth operation of the air-cooling island flushing can be realized.

Description

A steam distribution system for an air-cooled island

technical field

The invention relates to the technical field of steam distribution of an air-cooled island, in particular to a steam distribution system of an air-cooled island.

Background technique

The air cooling island is a heat exchange device used to condense and recover the exhaust steam of the steam turbine in the steam turbine generator set. As an important part of the direct air cooling unit, the exhaust steam of the steam turbine is condensed through forced or natural air convection during the operation of the unit. Recycle. Specifically, the exhaust steam of the steam turbine enters the convection tube bank from the exhaust device through the exhaust pipe and steam distribution pipe, and is condensed into water by forced cooling by fans or natural convection cooling in the convection tube bank. system. The steam is cooled in a closed cycle in the air-cooled island without contact with the outside world, so it will not cause water loss. Compared with traditional wet cooling units, it can save about 90% of water.

In the general air-cooling island design, isolation valves are installed at the inlets of the steam distribution pipes of each row of convection tube bundles, and the steam intake of each row of convection tube bundles is controlled by adjusting the opening of each isolation valve during operation. Before the unit is completed and put into production, the air-cooling island needs to be flushed with a large flow rate. During the flushing process, it is necessary to control each column of convection tube bundles to enter steam one by one through the isolation valve to ensure the flushing flow. At the initial start-up of the unit in winter, the steam exhaust volume of the steam turbine is small, and the isolation valve is generally used to control the steam intake of only one or two rows of convective tube bundles, so as to avoid the small steam volume and freezing caused by the steam inlet of each row. However, conventional isolation valves are large butterfly valves with poor sealing effect. Even if the isolation valve is fully closed, a small amount of steam will inevitably leak in during winter start-up, resulting in partial freezing of steam distribution pipes or convection pipe bundles. Moreover, almost all isolation valves are imported from abroad, with a single cost of nearly one million. The isolation valve remains normally open during the normal operation of the unit. The isolation valve is only operated when the unit is started and the air-cooling island is flushed. The frequency of use is low and the cost is high. The economy is poor, so some newly-built power plants canceled the isolation valve at the beginning of the design, but this also caused inconvenience in the start-up of the unit in winter and the flushing of the air-cooled island.

Contents of the invention

The purpose of the present invention is to provide a steam distribution system for an air-cooled island. The isolation valve in the prior art is replaced by an air bag that can be inflated and contracted by pumping air, which can effectively reduce costs and improve the sealing effect, and realize the Blocking and conduction to adapt to a variety of operations.

In order to achieve the above object, the present invention provides a steam distribution system for an air-cooled island, which includes a steam exhaust pipe and multiple groups of steam distribution pipes communicating with the exhaust pipe, the exhaust pipe communicates with the exhaust device, and each The steam distribution pipes communicate with a plurality of convection pipe bundles respectively, wherein each of the steam distribution pipes is provided with an air bag, and each of the air bags is respectively connected with an inflatable structure and an air extraction structure, and the inflatable structure can provide The airbags are inflated, and the airbags can be inflated and blocked to block the corresponding steam distribution pipes. The steam distribution pipe runs through.

The steam distribution system of the air-cooled island as described above, wherein the inflatable structure includes an inflatable main pipe and a plurality of inflatable branch pipes corresponding to each of the airbags, and one end of each of the inflatable branch pipes communicates with the inflatable main pipe , and the other end of each inflatable branch pipe communicates with the corresponding air bag.

The steam distribution system of the air-cooled island as described above, wherein each of the inflation branch pipes is provided with an inflation valve.

The steam distribution system of the air-cooled island as described above, wherein the air extraction structure includes an air extraction main pipe and a plurality of air extraction branch pipes corresponding to each of the airbags, and one end of each of the air extraction branch pipes is connected to the The air suction main pipe is connected, and the other end of each of the air suction branch pipes is respectively connected with the corresponding air bag.

In the steam distribution system of the air-cooled island as described above, each of the air extraction branch pipes is provided with an air extraction valve.

The steam distribution system of the air-cooled island as described above, wherein, inside each of the steam distribution pipes, positioning mesh plates are respectively provided on both sides of the corresponding airbag along the axial direction of the steam distribution pipes.

The steam distribution system of the air-cooled island as described above, wherein, the positioning mesh plate is a positioning mesh plate made of stainless steel.

The steam distribution system of the air-cooled island as described above, wherein, each of the airbags is respectively connected with a communication pipe, one end of the communication pipe communicates with the corresponding airbag, and the other end of each communication pipe runs through the corresponding The pipe wall of the steam distribution pipe extends to the outside of the steam distribution pipe and communicates with the pumping structure and the air-inflating structure through a tee.

In the steam distribution system of the air-cooled island as described above, inspection holes are respectively opened on the pipe wall of each of the steam distribution pipes, and each of the communication pipes passes through the inspection holes on the corresponding steam distribution pipes.

The steam distribution system of the air-cooled island as described above, wherein each of the inspection holes is detachably provided with a cover plate, and each of the communication pipes respectively passes through the cover plate provided at the corresponding inspection hole .

Compared with prior art, advantage of the present invention is as follows:

The steam distribution system of the air-cooled island provided by the present invention replaces the isolation valve in the prior art with an air bag that can be inflated and contracted by pumping air, which can effectively reduce costs; The sealing effect of the isolation valve is much higher than that of the isolation valve in the prior art; in addition, when the air bag is in a contracted state, the normal operation of the unit can be ensured smoothly, and by controlling the inflation of the air bag separately, the winter start of the unit and the flushing of the air cooling island can be realized The operation went smoothly.

Description of drawings

The following drawings are only intended to schematically illustrate and explain the present invention, and do not limit the scope of the present invention. in:

Fig. 1 is a schematic structural view of the steam distribution system of the air-cooled island provided by the present invention.

Explanation of reference numbers:

1. Exhaust pipe;

2. Steam distribution pipe;

21. Positioning mesh;

22. Cover plate;

3. Airbag;

31. Connecting pipe;

4. Inflatable structure;

41. Inflatable mother pipe;

42. Inflatable branch pipe;

421. Inflatable valve;

5. Air extraction structure;

51. Air extraction main pipe;

52. Air extraction branch pipe;

521, exhaust valve.

Detailed ways

In order to have a clearer understanding of the technical solutions, objectives and effects of the present invention, the specific implementation manners of the present invention will now be described with reference to the accompanying drawings.

As shown in Figure 1, the present invention provides a steam distribution system for an air-cooled island, including an exhaust pipe 1 and a plurality of sets of steam distribution pipes 2 communicated with the exhaust pipe 1, the exhaust pipe 1 communicates with the exhaust device, and Each steam distribution pipe 2 communicates with a plurality of convection tube bundles respectively, wherein each steam distribution pipe 2 is provided with an air bag 3, and each air bag 3 is respectively connected with an inflatable structure 4 and an air extraction structure 5, and the inflatable structure 4 can flow toward the air bag. 3. Inflate the airbag 3 until the outer surface of the airbag 3 is in close contact with the inner surface of the corresponding steam distribution pipe 2. In this way, the corresponding steam distribution pipe 2 is completely blocked. At this time, the unit can be started in winter and the air cooling island The flushing operation, and the air pumping structure 5 can extract the gas in the airbag 3, so that the airbag 3 shrinks. At this time, the outer surface of the airbag 3 is no longer attached to the inner surface of the steam distribution pipe 2, so that each steam distribution pipe 2 runs through , the steam can pass between the air bag 3 and the inner surface of the steam distribution pipe 2 to ensure the normal operation of the unit; the present invention uses the air bag 3 to replace the isolation valve, which has low cost and low maintenance and replacement costs in the later stage, and the air bag 3 has good sealing performance. It can effectively avoid the freezing problem caused by steam leakage.

Further, as shown in FIG. 1 , in the steam distribution system of an air-cooled island provided by the present invention, the inflatable structure 4 includes an inflatable main pipe 41 and a plurality of inflatable branch pipes 42 corresponding to each airbag 3 , and one end of each inflatable branch pipe 42 All are communicated with the inflation main pipe 41, and the other end of each inflation branch pipe 42 is communicated with the corresponding air bag 3 respectively, and each air bag 3 realizes the inflation operation through the corresponding inflation branch pipe 42 respectively, so as to realize the independent inflation of each air bag 3, and each inflation The branch pipes 42 are equipped with inflation valves 421, so as to cooperate with the air extraction structure 5 to control the air intake of each steam distribution pipe 2 and control the individual closing of each steam distribution pipe 2. The inflation gas source is compressed air for instrument use in the factory.

Further, as shown in FIG. 1 , in the steam distribution system of an air-cooled island provided by the present invention, the air extraction structure 5 includes an air extraction main pipe 51 and a plurality of air extraction branch pipes 52 corresponding to each air bag 3 , each air extraction One end of the branch pipe 52 is all communicated with the air extraction main pipe 51, and the other end of each air extraction branch pipe 52 is respectively communicated with the corresponding air bag 3, and each air bag 3 realizes the air extraction operation through the corresponding air extraction branch pipe 52 respectively, so as to realize the air extraction of each air bag. 3 independent air extraction, and each air extraction branch pipe 52 is equipped with an air extraction valve 521 to realize the independent air extraction operation of each air bag 3, so as to cooperate with the inflatable structure 4 to control the air intake of each steam distribution pipe 2 and control Separate opening of each steam distribution pipe 2; air extraction is connected to the vacuum system of the air-cooled island turbine.

Preferably, as shown in FIG. 1 , the steam distribution system of the air-cooled island provided by the present invention, wherein the interior of each steam distribution pipe 2 is respectively provided on both sides of the corresponding airbag 3 along the axial direction of the steam distribution pipe 2 There is a positioning net plate 21 , by setting the positioning net plate 21 , the position of the air bag 3 can be maintained during the process of the air bag 3 being inflated, pumped and contracted, and steam passing through the steam distribution pipe 2 .

Preferably, the positioning screen 21 is a positioning screen 21 made of stainless steel, so as to prevent the positioning screen 21 from being rusted due to contact with moisture in the steam.

Furthermore, as shown in FIG. 1 , in the steam distribution system of the air-cooled island provided by the present invention, each airbag 3 is respectively connected with a communication pipe 31, and one end of the communication pipe 31 communicates with the corresponding airbag 3, and each communication pipe 31 The other ends of the pipes respectively penetrate through the pipe wall of the corresponding steam distribution pipe 2 to the outside of the steam distribution pipe 2 and communicate with the air extraction structure 5 and the inflatable structure 4 through the tee. The inflatable structure 4 and the air extraction structure 5 can respectively pass through the three It communicates with the connecting pipe 31 to realize the inflation operation and the air extraction operation.

As a preference, as shown in Fig. 1, the steam distribution system of the air-cooled island provided by the present invention, wherein, the pipe walls of each steam distribution pipe 2 are respectively provided with inspection holes, and each inspection hole is provided with a detachable cover. Plate 22, and each connecting pipe 31 runs through the cover plate 22 provided at the inspection hole on the corresponding steam distribution pipe 2, and the inspection hole is used for the staff to enter the steam distribution pipe 2 to repair the airbag 3 and the two positioning mesh plates 21 , Clean or replace.

Compared with prior art, advantage of the present invention is as follows:

The steam distribution system of the air-cooled island provided by the present invention replaces the isolation valve in the prior art with an air bag that can be inflated and contracted by pumping air, which can effectively reduce costs; The sealing effect of the isolation valve is much higher than that of the isolation valve in the prior art; in addition, when the air bag is in a contracted state, the normal operation of the unit can be ensured smoothly, and by controlling the inflation of the air bag separately, the winter start of the unit and the flushing of the air cooling island can be realized The operation went smoothly.

The above descriptions are only illustrative specific implementations of the present invention, and are not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principle of the present invention shall fall within the protection scope of the present invention.

Claims (10)

1. A steam distribution system of an air-cooled island, comprising an exhaust pipe and multiple groups of steam distribution pipes communicated with the exhaust pipe, the exhaust pipe communicates with the exhaust device, and each of the steam distribution pipes corresponds to It communicates with a plurality of convection tube bundles, and it is characterized in that each of the steam distribution pipes is provided with an air bag, and each of the air bags is respectively connected with an inflatable structure and an air extraction structure, and the inflatable structure can inflate the air bag, so The airbags can be inflated and inflated to block the corresponding steam distribution pipes, and the pumping structure can extract the gas in the airbags, and each airbag can be pumped and contracted to allow the corresponding steam distribution pipes to pass through. 2. The steam distribution system of the air-cooled island according to claim 1, wherein the inflatable structure includes an inflatable main pipe and a plurality of inflatable branch pipes corresponding to each of the airbags, and one end of each of the inflatable branch pipes is It communicates with the inflatable main pipe, and the other end of each inflatable branch pipe communicates with the corresponding air bag respectively. 3 . The steam distribution system of the air-cooled island according to claim 2 , wherein each of the inflation branch pipes is provided with an inflation valve. 4 . 4. The steam distribution system of the air-cooled island according to claim 1, wherein the air extraction structure includes an air extraction main pipe and a plurality of air extraction branch pipes corresponding to each of the air bags, and each of the air extraction One end of the branch pipes communicates with the air suction main pipe, and the other end of each of the air suction branch pipes communicates with the corresponding air bag respectively. 5 . The steam distribution system of the air-cooled island according to claim 4 , wherein each of the air extraction branch pipes is provided with an air extraction valve. 6 . 6. The steam distribution system of an air-cooled island according to any one of claims 1 to 5, characterized in that, the inside of each steam distribution pipe is located in the axial direction of the corresponding airbag along the steam distribution pipe. The two sides of the top are respectively provided with positioning net plates. 7. The steam distribution system of the air-cooled island according to claim 6, wherein the positioning screen is made of stainless steel. 8. The steam distribution system of the air-cooled island according to claim 1, wherein each of the airbags is respectively connected with a connecting pipe, one end of the connecting pipe communicates with the corresponding airbag, and each of the communicating pipes The other ends of the pipes extend through the corresponding pipe walls of the steam distribution pipes to the outside of the steam distribution pipes and communicate with the air pumping structure and the air charging structure through a tee. 9. The steam distribution system of the air-cooled island according to claim 8, characterized in that, each of the steam distribution pipes is provided with a maintenance hole on the pipe wall, and each of the communication pipes runs through the corresponding steam distribution pipe above the manhole. 10. The steam distribution system of an air-cooled island according to claim 9, wherein a cover plate is detachably installed at each of the inspection holes, and each of the communication pipes runs through the corresponding inspection holes The cover set at the place.