CN112943390A - Low-pressure cylinder dehumidification drain tank structure of steam turbine and working method - Google Patents
Low-pressure cylinder dehumidification drain tank structure of steam turbine and working method Download PDFInfo
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- CN112943390A CN112943390A CN202110114112.XA CN202110114112A CN112943390A CN 112943390 A CN112943390 A CN 112943390A CN 202110114112 A CN202110114112 A CN 202110114112A CN 112943390 A CN112943390 A CN 112943390A
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- 238000007791 dehumidification Methods 0.000 title claims abstract description 84
- 238000000034 method Methods 0.000 title claims abstract description 22
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 42
- 230000002209 hydrophobic effect Effects 0.000 claims description 6
- 230000009471 action Effects 0.000 claims description 4
- 239000011229 interlayer Substances 0.000 claims description 3
- 238000011017 operating method Methods 0.000 claims 2
- 230000003628 erosive effect Effects 0.000 abstract description 7
- 230000000694 effects Effects 0.000 abstract description 5
- 239000007788 liquid Substances 0.000 abstract description 4
- 230000008569 process Effects 0.000 abstract description 4
- 230000008646 thermal stress Effects 0.000 abstract description 4
- 230000007704 transition Effects 0.000 abstract description 2
- 238000005516 engineering process Methods 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 238000005192 partition Methods 0.000 description 2
- 238000010248 power generation Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 230000035882 stress Effects 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 238000007664 blowing Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000005622 photoelectricity Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
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Classifications
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- 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
- F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
- F01D25/32—Collecting of condensation water; Drainage ; Removing solid particles
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Drying Of Gases (AREA)
Abstract
The invention discloses a dehumidification drain tank structure of a low-pressure cylinder of a steam turbine and a working method, wherein the dehumidification drain tank structure is a circular tank, and optimized rounding with different included angles is formed at the transition part of a steam inlet side and a steam outlet side of the inner wall of a low-pressure inner cylinder body of the steam turbine, so that tiny liquid drops in wet steam in the flowing process of the wet steam enter the dehumidification drain tank to be decelerated, condensed and collected, and the influence on the main flow of the wet steam is reduced; the bottom of the circular dehumidification drain tank of the lower half cylinder of the low-pressure inner cylinder of the steam turbine is provided with a drain through hole at the bottom of the drain tank with a certain diameter. The invention has more convenient application, relatively simple structure and flexible position, and the thermal stress of the structure position is relatively small, a plurality of dehumidification drainage grooves can be designed and processed in the low-pressure cylinder, the dehumidification effect is relatively ideal, the unit efficiency can be better improved, the water erosion degree of the last stage of low-pressure blades of the steam turbine is greatly reduced, and the safety of the steam turbine blades is ensured.
Description
Technical Field
The invention belongs to the field of power generation of a steam turbine, and particularly relates to a dehumidification drain tank structure of a low-pressure cylinder of the steam turbine and a working method.
Background
At present, the structure of a Chinese power supply is unreasonable, the occupation ratio of a thermal power generating unit is high, the peak regulation capability of a power grid is seriously insufficient, particularly, the rapid increase of wind power and photoelectricity in recent years and the problem that the power grid lacks a peak regulation power supply are particularly obvious, so that the phenomena of abandoning a large amount of wind and light and huge loss of renewable energy are caused. More new energy needs to be consumed, the power grid needs to have higher flexibility, however, flexible power supplies in the current power supply structure in China are few, the peak regulation capability is insufficient, and the main reason for wind and light abandonment is that. At present, the flexibility transformation of 2.2 hundred million kilowatt coal-fired units is planned to be implemented, so that the units have deep peak regulation capability, the load response rate of thermal power units is further improved, and part of the units have quick start-stop peak regulation capability. The improvement of flexibility and transformation expectation will increase the peak shaving capacity of the thermoelectric unit by 20% of rated capacity, and the minimum technical output reaches 40-50% of rated capacity; the pure condensing unit increases the peak regulation capacity of 15-20% of rated capacity, and the minimum technical output reaches 30-35% of rated capacity.
In the deep peak shaving operation process of most thermal power generating units, a steam turbine is in a low load state, the volume flow of last stages of blades of a low-pressure cylinder is small, the steam humidity is obviously increased, the in-stage flow state formed by the blades of the low-pressure cylinder can be greatly changed, flow separation is formed on the pressure surface of the blades, and phenomena such as air blast, water erosion and the like occur on the blades due to the defluidization at the blade roots. These changes not only affect the unit efficiency, but also aggravate the water erosion at the blade tips; the problem of wet steam faced by low-pressure cylinders of steam turbines of geothermal power stations and nuclear power generation is more prominent, and the continuous action of the water drops can cause the last stages of low-pressure moving blades to be impacted and eroded by high-speed water drops for a long time, so that the blades are gradually eroded by water, even broken, and the long-term safe operation of a unit is seriously influenced and threatened.
The earliest and most widely applied dehumidification method is an outer edge separation method, a dehumidification groove is arranged on the outer edge, water drops are thrown to the outer edge by utilizing the torsion and centrifugal effect of a mechanism on steam flow, and the water drops enter a condenser after passing through the groove. According to the dehumidification position, the internal dehumidification method of the steam turbine can be as follows 3: a stationary blade dehumidification technique, a movable blade dehumidification technique, and a diaphragm dehumidification technique.
In the existing wet steam dehumidification technology of the low-pressure cylinder of the steam turbine, hollow static blade suction, blowing and heating dehumidification methods, movable blade surface channel dehumidification methods, movable blade gap lengthening methods, partition plate device dehumidification methods and the like are adopted according to different dehumidification positions and dehumidification modes. However, the condition of severe water erosion still occurs in the low-pressure blades of the operating turbine, huge hidden dangers are buried for deep peak shaving and safe operation of the turbine of the unit, and uncertainty is brought to power grid stability.
Disclosure of Invention
The invention aims to overcome the defects and provides a low-pressure cylinder dehumidification drain tank structure of a steam turbine and a working method thereof, which are based on a stationary blade dehumidification technology and a partition plate dehumidification technology and have reasonable structure, higher efficiency and higher safety.
In order to achieve the purpose, the dehumidifying drain tank structure of the low-pressure cylinder of the steam turbine comprises a circular dehumidifying drain tank arranged in a low-pressure inner cylinder of the steam turbine, wherein a plurality of drain through holes are formed in the bottom of the circular dehumidifying drain tank, and the junction of the circular dehumidifying drain tank and the low-pressure inner cylinder of the steam turbine is provided with an inner wall steam inlet side radius and an inner wall steam outlet side radius.
The circular dehumidifying drain groove is arranged at the joint of the stationary blade outlet and the low-pressure inner cylinder or the joint of the moving blade outlet and the low-pressure inner cylinder of the steam turbine.
The positions corresponding to the upper cylinder and the lower cylinder of the low-pressure inner cylinder of the steam turbine are provided with circular dehumidification drain grooves.
The circular dehumidification drain tank and the steam inlet side and the steam outlet side of the inner wall of the low-pressure inner cylinder body of the steam turbine form an inner wall steam inlet side included angle and an inner wall steam outlet side included angle.
The included angle of the steam inlet side of the inner wall is different from the included angle of the steam outlet side of the inner wall.
A working method of a low-pressure cylinder dehumidification drain tank structure of a steam turbine comprises the following steps:
when wet steam flows through the low-pressure cylinder of the steam turbine, water drops in the wet steam are positioned on the inner wall of the low-pressure inner cylinder body of the steam turbine and adhere to and flow under the action of centrifugal stress;
a part of water drops are rounded along the steam inlet side of the inner wall of the circular dehumidification drainage tank and gradually separated from the main stream of the wet steam to enter the circular dehumidification drainage tank;
the other part of water drops impact on the steam outlet side of the inner wall and are rounded to enter the circular dehumidification drain tank;
the water drops entering the circular dehumidification drain tank are continuously collected to form water, and the water drops are collected near the drain through hole at the bottom of the drain tank facing to the lower half cylinder of the low-pressure cylinder of the steam turbine along the inner wall of the circular dehumidification drain tank and flow into the interlayer of the low-pressure inner and outer cylinders through the drain through hole.
And when a part of water drops enter the circular dehumidification drain tank from the steam inlet side of the inner wall in a rounding way, an included angle of the steam inlet side of the inner wall is formed.
The other part of water drops form an included angle of the steam outlet side of the inner wall when entering the circular dehumidification drain tank from the steam outlet side of the inner wall in a rounding mode.
Compared with the prior art, the dehumidification drain tank has the advantages that the structure of the dehumidification drain tank is a circular tank, and the transition part between the dehumidification drain tank and the steam inlet side and the steam outlet side of the inner wall of the low-pressure inner cylinder body of the steam turbine is optimized rounding with different included angles, so that tiny liquid drops in wet steam in the wet steam flowing process can conveniently enter the dehumidification drain tank to be decelerated, condensed and converged, and the influence on the main flow of the wet steam is reduced; the bottom of the circular dehumidification drain groove of the lower half cylinder of the low-pressure inner cylinder of the steam turbine is provided with a drain through hole at the bottom of the drain groove with a certain diameter. The invention has more convenient application, relatively simple structure and flexible position, and the thermal stress of the structure position is relatively small, a plurality of dehumidification drainage grooves can be designed and processed in the low-pressure cylinder, the dehumidification effect is relatively ideal, the unit efficiency can be better improved, the water erosion degree of the last stage of low-pressure blades of the steam turbine is greatly reduced, and the safety of the steam turbine blades is ensured.
When the invention works, a part of water drops gradually separate from the main stream of wet steam along the rounding of the steam inlet side of the inner wall of the circular dehumidification drain tank and enter the circular dehumidification drain tank, and the other part of water drops impact the rounding of the steam outlet side of the inner wall and enter the circular dehumidification drain tank. The invention has more convenient application, relatively simple structure and flexible position, and the thermal stress of the structure position is relatively small, a plurality of dehumidification drain grooves can be designed and processed in the low-pressure cylinder, the dehumidification effect is more ideal, the unit efficiency can be better improved, the water erosion degree of the last stages of low-pressure blades of the steam turbine is greatly reduced, and the safe and long-term operation of the last stages of low-pressure blades of the steam turbine is powerfully ensured.
Drawings
FIG. 1 is a schematic illustration of the present invention in position;
FIG. 2 is an internal structure view of the circular dehumidifying trap of the present invention;
wherein, 1, a low-pressure inner cylinder of a steam turbine; 2. a circular dehumidification drain tank; 3. a water drainage through hole is formed in the bottom of the water drainage groove; 4. the included angle of the steam inlet side of the inner wall; 5. the included angle of the steam outlet side of the inner wall; 6. the steam inlet side of the inner wall is rounded; 7. the steam outlet side of the inner wall is rounded.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
Referring to fig. 1 and 2, a steam turbine low pressure jar hydrophobic groove structure that dehumidifies, including setting up the circular hydrophobic groove 2 that dehumidifies in the steam turbine low pressure inner casing 1, a plurality of hydrophobic through-holes 3 by unit size and position decision are seted up to circular hydrophobic groove 2 bottom that dehumidifies, and inner wall admission side radius 6 and inner wall play steam side radius 7 have been seted up to circular hydrophobic groove 2 and the junction of steam turbine low pressure inner casing 1. The large micro liquid drops in the wet steam flow process are convenient to enter the dehumidification drain tank 2 to be decelerated and condensed and collected by the inner wall steam inlet side rounding 6 and the small micro liquid drops by the inner wall steam outlet side rounding 7 at the same time, and the influence on the main flow and the flow efficiency of the wet steam is reduced.
The circular dehumidification drain groove 2 is arranged at the joint of the stationary blade outlet and the low-pressure inner cylinder or the joint of the moving blade outlet and the low-pressure inner cylinder of the low-pressure inner cylinder 1 of the steam turbine. The positions corresponding to the upper cylinder and the lower cylinder of the low-pressure inner cylinder 1 of the steam turbine are provided with circular dehumidification drain grooves 2.
The round dehumidification drain tank 2 and the steam inlet side and the steam outlet side of the inner wall of the low-pressure inner cylinder body 1 of the steam turbine form an inner wall steam inlet side included angle 4 and an inner wall steam outlet side included angle 5. The included angle 4 of the steam inlet side of the inner wall is different from the included angle 5 of the steam outlet side of the inner wall.
A working method of a low-pressure cylinder dehumidification drain tank structure of a steam turbine comprises the following steps:
when the wet steam flows through the low-pressure cylinder of the steam turbine, water drops in the wet steam are positioned on the inner wall of the low-pressure inner cylinder body 1 of the steam turbine and adhere to and flow under the action of centrifugal stress;
a part of water drops gradually separate from the main flow of the wet steam and enter the circular dehumidification drain tank 2 along the rounding 6 at the steam inlet side of the inner wall of the circular dehumidification drain tank 2;
the other part of water drops impact the inner wall steam outlet side rounding 7 and enter the circular dehumidification drain tank 2;
the water drops entering the circular dehumidification drain tank 2 are continuously collected to form water, and the water drops are collected near the drain through hole 3 at the bottom of the drain tank facing the lower half cylinder of the low-pressure cylinder of the steam turbine along the inner wall of the circular dehumidification drain tank 2 and flow into the interlayer of the low-pressure inner cylinder and the low-pressure outer cylinder through the drain through hole 3.
When a part of water drops enter the circular dehumidification drain tank 2 from the inner wall steam inlet side rounding 6, an inner wall steam inlet side included angle 4 is formed.
The other part of water drops form an included angle 5 of the steam outlet side of the inner wall when entering the circular dehumidification drain tank 2 from the steam outlet side rounding 7 of the inner wall.
The invention provides a novel dehumidification drain tank structure of a steam turbine low-pressure cylinder, which is reasonable in optimized structure, more efficient and safer, and a use method. The invention has more convenient application, relatively simple structure and flexible position, and the thermal stress of the structure position is relatively small, a plurality of dehumidification drain grooves can be designed and processed in the low-pressure cylinder, the dehumidification effect is more ideal, the unit efficiency can be better improved, the water erosion degree of the last stage of low-pressure blades of the steam turbine is greatly reduced, and the safe and long-term operation of the last stage of low-pressure blades of the steam turbine is powerfully ensured.
Claims (8)
1. The utility model provides a steam turbine low pressure jar dehumidification drain trap structure, its characterized in that, including setting up circular dehumidification drain trap (2) in steam turbine low pressure inner casing (1), a plurality of hydrophobic through-holes (3) have been seted up to circular dehumidification drain trap (2) bottom, and inner wall admission side radius (6) and inner wall play vapour side radius (7) have been seted up to the junction of circular dehumidification drain trap (2) and steam turbine low pressure inner casing (1).
2. The steam turbine low pressure cylinder dehumidification drain tank structure according to claim 1, characterized in that the circular dehumidification drain tank (2) is opened at the place where the stationary blade outlet of the steam turbine low pressure inner cylinder (1) is connected with the low pressure inner cylinder or the moving blade outlet is connected with the low pressure inner cylinder.
3. The steam turbine low-pressure cylinder dehumidification water drainage tank structure according to claim 2, characterized in that the circular dehumidification water drainage tank (2) is arranged at the corresponding position of the upper cylinder and the lower cylinder of the steam turbine low-pressure inner cylinder (1).
4. The steam turbine low pressure cylinder dehumidification steam trap structure according to claim 1, wherein the circular dehumidification steam trap (2) forms an inner wall steam inlet side included angle (4) and an inner wall steam outlet side included angle (5) with a steam inlet side and a steam outlet side of the inner wall of the steam turbine low pressure inner cylinder body (1).
5. The steam turbine low pressure cylinder dehumidification steam trap structure according to claim 4, wherein the included angle (4) of the steam inlet side of the inner wall and the included angle (5) of the steam outlet side of the inner wall are different.
6. The method for operating a low pressure cylinder dehumidification steam trap structure of a steam turbine as set forth in claim 1, comprising the steps of:
when wet steam flows through the low-pressure cylinder of the steam turbine, water drops in the wet steam are positioned on the inner wall of the low-pressure inner cylinder body (1) of the steam turbine and adhere to and flow under the action of centrifugal stress;
a part of water drops gradually separate from the main flow of the wet steam and enter the circular dehumidification drain tank (2) along the steam inlet side rounding (6) of the inner wall of the circular dehumidification drain tank (2);
the other part of water drops impact the inner wall steam outlet side rounding (7) and enter the circular dehumidification drain tank (2);
the water drops entering the circular dehumidification drain tank (2) are continuously collected to form water, and the water drops are gathered near the drain tank bottom drain through hole (3) facing the lower half cylinder of the low-pressure cylinder of the steam turbine along the inner wall of the circular dehumidification drain tank (2) and flow into the interlayer of the low-pressure inner cylinder and the low-pressure outer cylinder through the drain through hole (3).
7. The operating method of the low pressure cylinder dehumidification steam trap structure of the steam turbine according to claim 6, wherein a part of water drops form the inner wall steam inlet side included angle (4) when entering the circular dehumidification steam trap (2) from the inner wall steam inlet side rounding (6).
8. The operating method of the low pressure cylinder dehumidification steam trap structure of the steam turbine according to claim 6, wherein the inner wall steam outlet side included angle (5) is formed when another part of water drops enter the circular dehumidification steam trap (2) from the inner wall steam outlet side rounding (7).
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110114112.XA CN112943390A (en) | 2021-01-27 | 2021-01-27 | Low-pressure cylinder dehumidification drain tank structure of steam turbine and working method |
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| CN202110114112.XA CN112943390A (en) | 2021-01-27 | 2021-01-27 | Low-pressure cylinder dehumidification drain tank structure of steam turbine and working method |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3973870A (en) * | 1974-11-04 | 1976-08-10 | Westinghouse Electric Corporation | Internal moisture removal scheme for low pressure axial flow steam turbine |
| GB2122690A (en) * | 1982-07-01 | 1984-01-18 | Skoda Kp | Steam turbine bleeding slot |
| CN1182466A (en) * | 1995-03-20 | 1998-05-20 | 西屋电气公司 | Moisture removal slot for steam turbine |
| JP2009138540A (en) * | 2007-12-04 | 2009-06-25 | Toshiba Corp | Steam turbine and moisture removing structure for steam turbine stage |
| CN110043336A (en) * | 2019-05-21 | 2019-07-23 | 中国船舶重工集团公司第七0三研究所 | A kind of ocean movable type nuclear steam turbine outer rim dehumidification device |
| CN211174239U (en) * | 2019-11-25 | 2020-08-04 | 东方电气集团东方汽轮机有限公司 | Low-pressure final-stage steam exhaust flow guide ring device for zero-output reconstruction of steam turbine |
-
2021
- 2021-01-27 CN CN202110114112.XA patent/CN112943390A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3973870A (en) * | 1974-11-04 | 1976-08-10 | Westinghouse Electric Corporation | Internal moisture removal scheme for low pressure axial flow steam turbine |
| GB2122690A (en) * | 1982-07-01 | 1984-01-18 | Skoda Kp | Steam turbine bleeding slot |
| CN1182466A (en) * | 1995-03-20 | 1998-05-20 | 西屋电气公司 | Moisture removal slot for steam turbine |
| JP2009138540A (en) * | 2007-12-04 | 2009-06-25 | Toshiba Corp | Steam turbine and moisture removing structure for steam turbine stage |
| CN110043336A (en) * | 2019-05-21 | 2019-07-23 | 中国船舶重工集团公司第七0三研究所 | A kind of ocean movable type nuclear steam turbine outer rim dehumidification device |
| CN211174239U (en) * | 2019-11-25 | 2020-08-04 | 东方电气集团东方汽轮机有限公司 | Low-pressure final-stage steam exhaust flow guide ring device for zero-output reconstruction of steam turbine |
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Application publication date: 20210611 |
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