CN108799619B - Flow guiding structure of lifting valve - Google Patents
Flow guiding structure of lifting valve Download PDFInfo
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- CN108799619B CN108799619B CN201810980168.1A CN201810980168A CN108799619B CN 108799619 B CN108799619 B CN 108799619B CN 201810980168 A CN201810980168 A CN 201810980168A CN 108799619 B CN108799619 B CN 108799619B
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- exhaust pipe
- valve
- steam exhaust
- flow guide
- valve disc
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K47/00—Means in valves for absorbing fluid energy
- F16K47/02—Means in valves for absorbing fluid energy for preventing water-hammer or noise
- F16K47/023—Means in valves for absorbing fluid energy for preventing water-hammer or noise for preventing water-hammer, e.g. damping of the valve movement
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- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
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Abstract
The invention provides a flow guide structure for a lifting valve with a plurality of outlet pipelines, which comprises a valve disc, an exhaust pipe and a plurality of flow guide clapboards, wherein the valve disc is provided with a plurality of outlet pipelines; the valve disc is in a flat-bottom notch shape, the valve disc and the steam exhaust pipe are coaxially arranged up and down, and the lower end of the valve disc is in blocking fit with the upper end of the steam exhaust pipe; the valve disc and the blocking matching part of the steam exhaust pipe form the throat part of the lifting valve, all the flow guide partition plates are uniformly distributed in the throat part in a radial manner by taking the axis of the steam exhaust pipe as the center, and the inner cavity of the steam exhaust pipe which belongs to the downstream of the throat part is equally divided into a plurality of steam exhaust channels which are communicated up and down. The valve throat outlet rotary steam flow can be prevented from making circular motion at the throat outlet of the lifting valve by taking the axis of the valve disc as the center, so that the steam can be inhibited from forming low-frequency longitudinal waves in a plurality of outlet pipelines of the lifting valve, and the formation of exciting force in a downstream channel is avoided.
Description
Technical Field
The invention relates to the technology of steam turbines, in particular to a flow guide structure of a lifting valve.
Background
The research on the valve structure has very important significance in the field of steam turbines. Knowing and mastering the internal structure of fluid flowing in the valve can guide and improve the pneumatic performance of the valve and has important influence on improving the overall performance of the valve. In addition, the influence of the flow state of the fluid at the outlet of the valve on the downstream can be clearly mastered by knowing the structure of the flow field in the valve, and the method has important significance for controlling the flow of the fluid.
As shown in fig. 1, the poppet valve includes a butterfly valve 1 and an exhaust pipe 2, and when the poppet valve is in a small opening, the fluid generally flows downstream close to the inner peripheral wall of the exhaust pipe 2 after passing through the valve throat, so that an annular backflow region 3 is formed at the valve throat, that is, the steam near the inner peripheral wall of the exhaust pipe flows downward, and the steam at the center of the exhaust pipe flows upward. In addition, the tail of the high velocity jet attached to the inner peripheral wall of the exhaust pipe forms a pulsation of extremely high frequency due to flow instability, but the energy of the high frequency pulsation is low and is generally dissipated in a short distance downstream of the exhaust pipe. When the opening degree and the pressure ratio of the poppet valve are within some ranges, the annular backflow zone 3 cannot be kept stable, and an asymmetric backflow structure is formed, for example, as shown in fig. 2, the annular backflow zone 3 on the right side suppresses the annular backflow zone 3 on the left side, so that the range of the annular backflow zone 3 is expanded to the inside of the notch cavity of the valve disc 1, at this time, due to circumferential instability, the backflow structure can form low-frequency circular motion along the circumferential direction of the exhaust pipe, so that the mass flow is not uniformly distributed on the circumferential direction of the exhaust pipe, the mass center of the cross-sectional fluid deviates from the axis of the exhaust pipe and makes circular motion, and therefore, the rotational flow formed in the exhaust pipe is different from a common rotational flow, and the distribution of the pneumatic.
Generally, the above-mentioned backflow structure will not produce adverse effect, but when the downstream of the poppet valve is connected with a three-way component or other multi-channel shunt components, and the main flow makes a circular motion along the circumference of the exhaust pipe, the main flow will flow into each shunt pipe one by one, each shunt pipe will have main flow flowing in for a while, and will not have main flow flowing in for a while, resulting in that the fluid in the same shunt pipe forms dilatational waves, i.e. longitudinal waves (generally low frequency), and the low-frequency longitudinal waves formed in each shunt pipe have the same frequency and different phases, which may form low-frequency excitation force to the downstream components, if the frequency of the excitation force is coupled with the natural frequency of the components, resonance may be induced; when the shunt pipelines converge, longitudinal waves in the shunt pipelines can be superposed to form stronger exciting force, and the operation safety of the downstream part of the lifting valve is seriously threatened.
Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a flow guiding structure of a poppet valve, which can block steam from making a circular motion at a throat portion of the poppet valve along a circumferential direction of a steam exhaust pipe, so as to inhibit the steam from forming a circumferential rotational flow.
In order to solve the technical problem, the invention provides a flow guide structure of a lifting valve, which comprises a valve disc, an exhaust pipe and a plurality of flow guide clapboards; the valve disc is in a flat-bottom notch shape, the valve disc and the steam exhaust pipe are coaxially arranged up and down, and the lower end of the valve disc is in blocking fit with the upper end of the steam exhaust pipe; the valve disc and the blocking matching part of the steam exhaust pipe form the throat part of the lifting valve, all the flow guide partition plates are uniformly distributed in the throat part in a radial manner by taking the axis of the steam exhaust pipe as the center, and the inner cavity of the steam exhaust pipe which belongs to the downstream of the throat part is equally divided into a plurality of steam exhaust channels which are communicated up and down.
Preferably, each flow guide partition plate is vertically divided into a suspension section and a separation section, the separation section is connected with the inner peripheral wall of the steam exhaust pipe along the radial outer side edge of the steam exhaust pipe, the suspension section upwards extends into the notch cavity of the valve disc, and the suspension section does not touch the inner peripheral wall of the notch cavity along the radial outer side edge of the steam exhaust pipe.
Preferably, the inner diameter of the steam exhaust pipe is D1, the length of the separation section along the axial direction of the steam exhaust pipe is L1, and D1 is equal to or less than L1 and equal to or less than 2D 1.
Preferably, the inner diameter of the concave cavity is D2, the length of the top side of the suspended section is D, and D is 0.25-D2.
Preferably, the outer side edge of the suspended section along the radial direction of the steam exhaust pipe is an inclined side edge, the included angle between the inclined side edge and the horizontal direction is theta, and theta is more than or equal to 60 degrees and less than or equal to 80 degrees.
Preferably, the shortest distance between the outer side edge of the suspended section along the radial direction of the steam exhaust pipe and the inner peripheral wall of the concave cavity is delta, and delta is more than or equal to 2mm and less than or equal to 5 mm.
Preferably, the thickness of the flow guide partition plate is sigma, and the thickness of the flow guide partition plate is more than or equal to 1mm and less than or equal to 3 mm.
Preferably, the number of the flow guide partition plates is three, and the included angle between every two adjacent flow guide partition plates is 120 degrees.
Preferably, the number of the flow guide partition plates is four, and the included angle between every two adjacent flow guide partition plates is 90 degrees.
Preferably, the number of the flow guide partition plates is N, N is more than or equal to 5 and less than or equal to 10, and the included angle between every two adjacent flow guide partition plates is 360/N degrees.
As described above, the flow guiding structure of the poppet valve of the present invention has the following beneficial effects: according to the invention, the lifting valve equally divides the inner cavity of the exhaust pipe at the downstream of the throat into a plurality of exhaust passages which are communicated up and down through a plurality of flow guide partition plates, so that even if unstable annular backflow is generated by the lifting valve under a special working condition, the unstable annular backflow can be limited in each exhaust passage, the circular flow of the outlet at the throat of the valve is blocked to move circularly at the outlet at the throat of the lifting valve by taking the axis of a valve disc as the center, and further the circumferential cyclone can be inhibited from being formed, so that the steam can be inhibited from forming low-frequency longitudinal waves in a plurality of outlet pipelines of the lifting valve, the exciting force of low-frequency fluid in the downstream passage is prevented from being formed, and the hidden danger of threatening the safe operation of downstream parts of the valve is.
Drawings
FIG. 1 shows a first schematic view of a poppet-type valve of the prior art;
FIG. 2 is a second schematic view of a poppet-type valve of the prior art;
FIG. 3 is a longitudinal sectional view of the flow directing structure of the poppet valve of the present invention;
FIG. 4 is an enlarged view of a portion of FIG. 3;
FIG. 5 is an enlarged view of portion A of FIG. 4;
FIG. 6 is a cross-sectional view of the flow directing structure of the poppet valve of the present invention;
fig. 7 is an enlarged view of a portion B in fig. 6.
Description of the element reference numerals
1 valve disc
1a notch cavity
2 exhaust pipe
2a exhaust channel
3 reflux zone
4 flow guiding clapboard
4a flying segment
4aa oblique side
4ab topside
4b divided section
4ba separating section along the radial outer side edge of the steam exhaust pipe
5 throat part
Detailed Description
The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure.
It should be understood that the structures, ratios, sizes, and the like shown in the drawings are only used for matching the disclosure of the present disclosure, and are not used for limiting the conditions that the present disclosure can be implemented, so that the present disclosure is not limited to the technical essence, and any structural modifications, ratio changes, or size adjustments should still fall within the scope of the present disclosure without affecting the efficacy and the achievable purpose of the present disclosure. In addition, the terms "upper", "lower", "left", "right", "middle" and "one" used in the present specification are for clarity of description, and are not intended to limit the scope of the present invention, and the relative relationship between the terms and the terms is not to be construed as a scope of the present invention.
As shown in fig. 3, 4 and 6, the invention provides a flow guiding structure of a poppet valve, which comprises a valve disc 1, an exhaust pipe 2 and a plurality of flow guiding clapboards 4; the valve disc 1 is in a flat-bottom notch shape, the valve disc 1 and the steam exhaust pipe 2 are coaxially arranged up and down, and the lower end of the valve disc 1 is in blocking fit with the upper end of the steam exhaust pipe 2; the sealing and matching part of the valve disc 1 and the steam exhaust pipe 2 forms a throat part 5 (an area limited by a dashed line frame in figure 3) of the lifting valve, all flow guide partition plates 4 are uniformly distributed on the throat part 5 in a radial mode by taking the axis of the steam exhaust pipe as the center, and an inner cavity of the steam exhaust pipe belonging to the downstream of the throat part is uniformly divided into a plurality of steam exhaust channels 2a which are communicated up and down. For example, the number of the flow guide partition plates 4 may be two, the included angle between adjacent flow guide partition plates 4 is 180 degrees, and the inner cavity of the exhaust pipe belonging to the downstream of the throat part is equally divided into two exhaust passages 2a which are communicated up and down; the number of the flow guide partition plates 4 can be three, the included angle between every two adjacent flow guide partition plates 4 is 120 degrees, and the inner cavity of the steam exhaust pipe belonging to the downstream of the throat part is evenly divided into three steam exhaust channels 2a which are communicated up and down; the number of baffles 4 may be other.
In the invention, the lifting valve equally divides the inner cavity of the exhaust pipe at the downstream of the throat into a plurality of exhaust passages 2a which are communicated up and down through a plurality of flow guide partition plates 4, so that even if unstable annular backflow is generated by the lifting valve under a special working condition, the unstable annular backflow can be limited in each exhaust passage, the circular flow at the outlet of the throat of the lifting valve is blocked to do circular motion at the outlet of the throat of the lifting valve by taking the axis of a valve disc as the center, and further the circumferential rotational flow can be inhibited to form, thereby inhibiting the steam from forming low-frequency longitudinal waves in a plurality of outlet pipelines of the lifting valve, preventing the exciting force of low-frequency fluid from being formed in the downstream passages, and eliminating the hidden danger of safe operation of downstream parts of the valve.
Because the annular backflow zone 3 (see fig. 2 in detail) extends from the inlet of the notch cavity of the valve disc 1 to the downstream of the throat of the steam exhaust pipe 2, in order to limit backflow in the notch cavity and the inner cavity of the steam exhaust pipe in the corresponding steam exhaust channel, each flow guide partition plate 4 is divided into an overhanging section 4a and a separating section 4b from top to bottom, the separating section is connected with the inner peripheral wall of the steam exhaust pipe 2 along the radial outer side 4ba of the steam exhaust pipe, and the overhanging section 4a extends upwards into the notch cavity of the valve disc 1. In addition, the outer side edge of the suspension section along the radial direction of the steam exhaust pipe does not touch the inner peripheral wall of the concave cavity 1a, so that the flow guide partition plate 4 does not interfere with the up-and-down movement of the valve disc 1.
The inner diameter of the steam exhaust pipe 2 is D1, the length of the separation section along the axial direction of the steam exhaust pipe is L1, and L1 is more than or equal to D1 and less than or equal to 2.D 1. It was found that there was no annular recirculation zone 3 in the interior of the exhaust pipe below the throat 2. D1. Therefore, the length L1(D1 is more than or equal to L1 is more than or equal to 2. D1) is adopted for the separating section, so that the generation of circumferential rotational flow is avoided, and the length of the separating section in the axial direction of the steam exhaust pipe is reduced.
The inner diameter of the pocket 1a is D2, and the length of the top side 4ab of the suspended section is D, which is 0.25 · D2, so that the occurrence of circumferential swirling flow in the pocket of the valve disc 1 can be further avoided.
The outer side edge of the suspended section along the radial direction of the steam exhaust pipe is an inclined side edge 4aa, the included angle between the inclined side edge 4aa and the horizontal direction is theta, theta is not less than 60 degrees and not more than 80 degrees, and therefore the circumferential rotational flow in the notch cavity of the valve disc 1 can be avoided.
As shown in fig. 5, the shortest distance between the outer side edge of the suspension section along the radial direction of the steam exhaust pipe and the inner peripheral wall of the concave cavity (1a) is δ, δ is not less than 2mm and not more than 5mm, so that the flow guide partition plate 4 can not interfere with the up-and-down movement of the valve disc 1, and the generation of circumferential rotational flow in the concave cavity of the valve disc 1 can be avoided.
As shown in FIG. 7, the thickness of the baffle 4 is σ, and σ is not less than 1mm and not more than 3mm, so that the rigidity and the strength of the baffle 4 can be ensured, and the steam flux in the steam exhaust pipe can not be influenced.
The length of the suspended portion in the axial direction of the exhaust pipe is L2, and L2 can be determined from D1, D, and θ, that is, L2 is (0.5D 1-D) tan θ.
The number of the flow guide partition plates 4 can be three, and the included angle between every two adjacent flow guide partition plates 4 is 120 degrees; as shown in fig. 6, the number of the baffle plates 4 may be four, an included angle between adjacent baffle plates 4 is 90 degrees, and the four baffle plates 4 do not affect the steam flow flux in the steam exhaust pipe on one hand, and can well limit the backflow in the four steam exhaust channels on the other hand; the number of the flow guide partition plates 4 can also be N, N is more than or equal to 5 and less than or equal to 10, and the included angle between every two adjacent flow guide partition plates 4 is 360/N degrees.
In conclusion, the valve can prevent the valve throat outlet swirl steam from making circular motion at the throat outlet of the lifting valve by taking the axis of the valve disc as the center, and further can inhibit the formation of circumferential swirl. Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.
Claims (9)
1. The utility model provides a promote water conservancy diversion structure of formula valve which characterized in that: comprises a valve disc (1), a steam exhaust pipe (2) and a plurality of flow guide clapboards (4); the valve disc (1) is in a flat-bottom notch shape, the valve disc (1) and the steam exhaust pipe (2) are coaxially arranged up and down, and the lower end of the valve disc (1) and the upper end of the steam exhaust pipe (2) form a sealing and blocking fit; the valve disc (1) and the blocking matching part of the steam exhaust pipe (2) form a throat part (5) of the lifting valve, all flow guide partition plates (4) are uniformly distributed on the throat part (5) in a radial manner by taking the axis of the steam exhaust pipe as the center, and the inner cavity of the steam exhaust pipe belonging to the downstream of the throat part is uniformly divided into a plurality of steam exhaust channels (2a) which are communicated up and down; every division board (4) divide into suspension section (4a) and dissection section (4b) from top to bottom, and the dissection section links to each other with the internal perisporium of exhaust pipe (2) along exhaust pipe radial outside limit (4ba), and suspension section (4a) upwards stretches into to the notch intracavity of valve dish (1) to suspension section does not touch along the radial outside limit of exhaust pipe the internal perisporium of notch intracavity (1 a).
2. The poppet valve guide structure of claim 1, wherein: the inner diameter of the steam exhaust pipe (2) is D1The length of the separation section along the axial direction of the exhaust pipe is L1，D1≤L1≤2·D1。
3. The poppet valve guide structure of claim 1, wherein: the inner diameter of the concave cavity (1a) is D2The length of the top side (4ab) of the suspension section is D, D is 0.25. D2。
4. The poppet valve guide structure of claim 3, wherein: the outer side edge of the suspended section along the radial direction of the steam exhaust pipe is an inclined side edge (4aa), the included angle between the inclined side edge (4aa) and the horizontal direction is theta, and theta is more than or equal to 60 degrees and less than or equal to 80 degrees.
5. The poppet valve guide structure of claim 1, wherein: the shortest distance between the outer side edge of the suspension section along the radial direction of the steam exhaust pipe and the inner peripheral wall of the concave cavity (1a) is delta, and delta is more than or equal to 2mm and less than or equal to 5 mm.
6. The poppet valve guide structure of claim 1, wherein: the thickness of the flow guide partition plate (4) is sigma, and sigma is more than or equal to 1mm and less than or equal to 3 mm.
7. The poppet valve guide structure of claim 1, wherein: the number of the flow guide partition plates (4) is three, and the included angle between every two adjacent flow guide partition plates (4) is 120 degrees.
8. The poppet valve guide structure of claim 1, wherein: the number of the flow guide partition plates (4) is four, and the included angle between every two adjacent flow guide partition plates (4) is 90 degrees.
9. The poppet valve guide structure of claim 1, wherein: the number of the flow guide partition plates (4) is N, N is more than or equal to 5 and less than or equal to 10, and the included angle between every two adjacent flow guide partition plates (4) is 360/N degrees.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810980168.1A CN108799619B (en) | 2018-08-27 | 2018-08-27 | Flow guiding structure of lifting valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810980168.1A CN108799619B (en) | 2018-08-27 | 2018-08-27 | Flow guiding structure of lifting valve |
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| Publication Number | Publication Date |
|---|---|
| CN108799619A CN108799619A (en) | 2018-11-13 |
| CN108799619B true CN108799619B (en) | 2020-02-18 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810980168.1A Active CN108799619B (en) | 2018-08-27 | 2018-08-27 | Flow guiding structure of lifting valve |
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| CN (1) | CN108799619B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU962711A1 (en) * | 1981-03-16 | 1982-09-30 | Московское Ордена Ленина,Ордена Октябрьской Революции И Ордена Трудового Красного Знамени Высшее Техническое Училище Им. Н.Э.Баумана | Air separation unit regenerator assembly gas valve |
| CN1050082A (en) * | 1989-08-24 | 1991-03-20 | 基斯通国际集团公司 | The decompression and the modulating valve that have improved |
| CN1060901A (en) * | 1990-09-13 | 1992-05-06 | Gec阿尔斯托姆有限公司 | Valve with valve seat of band block |
| CN101285405A (en) * | 2008-06-03 | 2008-10-15 | 东方电气集团东方汽轮机有限公司 | Steam turbine steam extraction regulation valve |
| CN201225170Y (en) * | 2008-06-30 | 2009-04-22 | 上海电气电站设备有限公司 | Steam turbine main air valve adjusting integral valve dish |
| CN106795776A (en) * | 2014-10-28 | 2017-05-31 | 三菱日立电力系统株式会社 | Main steam valve and steam turbine |
-
2018
- 2018-08-27 CN CN201810980168.1A patent/CN108799619B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU962711A1 (en) * | 1981-03-16 | 1982-09-30 | Московское Ордена Ленина,Ордена Октябрьской Революции И Ордена Трудового Красного Знамени Высшее Техническое Училище Им. Н.Э.Баумана | Air separation unit regenerator assembly gas valve |
| CN1050082A (en) * | 1989-08-24 | 1991-03-20 | 基斯通国际集团公司 | The decompression and the modulating valve that have improved |
| CN1060901A (en) * | 1990-09-13 | 1992-05-06 | Gec阿尔斯托姆有限公司 | Valve with valve seat of band block |
| CN101285405A (en) * | 2008-06-03 | 2008-10-15 | 东方电气集团东方汽轮机有限公司 | Steam turbine steam extraction regulation valve |
| CN201225170Y (en) * | 2008-06-30 | 2009-04-22 | 上海电气电站设备有限公司 | Steam turbine main air valve adjusting integral valve dish |
| CN106795776A (en) * | 2014-10-28 | 2017-05-31 | 三菱日立电力系统株式会社 | Main steam valve and steam turbine |
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| Publication number | Publication date |
|---|---|
| CN108799619A (en) | 2018-11-13 |
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