CN112032327A

CN112032327A - Regulating valve profile structure and regulating valve

Info

Publication number: CN112032327A
Application number: CN202010962016.6A
Authority: CN
Inventors: 肖蕾; 徐嗣华; 何劲; 胡志强; 李月月
Original assignee: Shanghai Electric Power Generation Equipment Co Ltd
Current assignee: Shanghai Electric Power Generation Equipment Co Ltd
Priority date: 2020-09-14
Filing date: 2020-09-14
Publication date: 2020-12-04
Anticipated expiration: 2040-09-14
Also published as: CN112032327B

Abstract

The invention provides a regulating valve molded line structure and a regulating valve adopting the molded line structure, wherein the regulating valve molded line structure comprises a valve disc molded line and is arranged on a valve disc, and the valve disc molded line comprises a sealing section molded line, a flow control section molded line and a valve disc head molded line which are sequentially connected; the valve seat molded line is arranged on the valve seat; the flow control section molded line comprises a first cut section molded line, an arc section molded line and a second cut section molded line which are sequentially connected, the arc section molded line is provided with a first end point and a second end point, the first cut section molded line and the arc section molded line are tangent to the first end point, the second cut section molded line and the arc section molded line are tangent to the second end point, the first cut section molded line is connected with the sealing section molded line, and the second cut section molded line is connected with the valve disc head molded line. The molded line structure has higher flow regulation precision under the working condition of small opening degree, and can ensure higher through-flow capacity under the working condition of full opening.

Description

Regulating valve profile structure and regulating valve

Technical Field

The invention relates to the technical field of regulating valves, in particular to a regulating valve profile structure and a regulating valve.

Background

The steam inlet valve of the steam turbine is used for controlling and adjusting high-temperature and high-pressure steam from the boiler so as to adapt to the requirements of starting and output power change of the steam turbine. For a traditional steam turbine adopting a unit system to operate, a sliding pressure starting mode is mostly adopted, steam parameters before a valve are low in the starting process, and the volume capacity of corresponding steam is large, so that the requirement on the regulation precision of the working condition of small opening degree of a steam inlet valve is relatively low. The steam turbine which is operated by adopting a unit system at present is configured with a mature steam inlet regulating valve, the molded line of the steam inlet regulating valve is developed by taking the regulating characteristic of the full stroke of the valve into consideration, the flow of the steam inlet regulating valve is linearly changed along with the opening of the valve in a valve stroke interval within 60 percent of the opening, namely the regulating precision of the valve under different openings is the same.

However, for an industrial turbine operated by a main pipe system, a full-parameter starting mode is adopted, the pressure before a cold starting valve is almost equal to the rated pressure, and the volume flow of steam is relatively small. If the same steam inlet regulating valve molded line and the same steam inlet flow rate of the unit-system operation steam turbine are adopted, smaller valve opening is needed, the valve opening is often needed to be stabilized below 1mm under the warming-up working condition, a control system is difficult to realize, and the regulating precision of the valve per se cannot meet the starting requirement of the unit, so that the problems of sudden jump of the rotating speed, fast flying and the like can be caused when the unit is started, and the safe and stable operation of the unit is influenced.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a line structure of a regulating valve and a regulating valve, which are used to solve the technical problem that the steam flow rate of the existing steam inlet regulating valve is low in regulating precision under a small opening degree.

To achieve the above and other related objects, the present invention provides a regulator valve-line structure, the regulator valve including a valve disc and a valve seat, the regulator valve-line structure including:

the valve disc molded line is arranged on the valve disc and comprises a sealing section molded line, a flow control section molded line and a valve disc head molded line which are sequentially connected;

the valve seat molded line is arranged on the valve seat;

the flow control section molded line comprises a first cut section molded line, an arc section molded line and a second cut section molded line which are sequentially connected, the arc section molded line is provided with a first end point and a second end point, the first cut section molded line and the arc section molded line are tangent to the first end point, the second cut section molded line and the arc section molded line are tangent to the second end point, the first cut section molded line is connected with the sealing section molded line, and the second cut section molded line is connected with the valve disc head molded line.

In an alternative embodiment, the seal segment profile has a first mating seal point thereon; the valve seat type line is provided with a second matching sealing point which is matched and sealed with the first matching sealing point.

In an optional embodiment, the seal section molded line is a straight line section or an arc-shaped section, if the seal section molded line is a straight line section, an included angle between the straight line section and a first direction is between 30 ° and 60 °, and the first direction is perpendicular to an axial direction of the valve disc body.

In an alternative embodiment, the first cut segment profile comprises a straight segment, the first cut segment profile being parallel to an axial direction of the valve disc body.

In an optional embodiment, a gap is reserved between the first tangent line segment profile and the valve seat profile.

In an optional embodiment, the second tangential line includes a straight line segment, an included angle between the second tangential line and a first direction is between 20 ° and 40 °, and the first direction is perpendicular to an axial direction of the valve disc body.

In an alternative embodiment, the valve disc head portion of the valve disc body includes a straight section or is concave.

In an alternative embodiment, the valve seat profile comprises a circular arc.

To achieve the above and other related objects, the present invention also provides a regulator valve, including:

a valve body;

a valve seat having a seat profile;

the valve disc is provided with a valve disc molded line, and the valve disc molded line comprises a sealing section molded line, a flow control section molded line and a valve disc head molded line which are sequentially connected;

a valve stem; and

a valve cover;

In an alternative embodiment, the outer wall of the valve disc is provided with an annular groove.

The regulating valve profile structure is suitable for a steam turbine adopting a full-parameter starting mode, and has the advantages of small opening degree, high regulating precision, large opening degree and high through-flow capacity;

according to the valve profile structure of the regulating valve, the valve disc profile is in a multi-section form, the sealing effect and the flow regulating effect of the valve are realized through two sections of profiles (the sealing section and the flow control section) respectively, and the regulating characteristic of the valve profile can be more flexibly optimized through the design of the multi-section profile;

according to the regulating valve profile structure, the head part of the valve disc is in a flat section or an inward concave shape, so that fluctuation generated by steam flow impact during the operation process of the regulating valve can be effectively reduced, and the stability of the regulating valve is improved;

the outer wall of the valve disc of the regulating valve adopting the regulating valve molded line is provided with the annular groove structure for collecting impurities in steam, so that the sealing surfaces (the sealing surface of the valve disc and the sealing surface of the valve seat) of the regulating valve can be prevented from being damaged by erosion of hard particles, and the leakage of the regulating valve can be prevented.

Drawings

FIG. 1 is a schematic diagram of the regulator valve profile of the present invention.

Fig. 2 shows a graph comparing the flow characteristics of the regulator valve profile of the present invention and a typical regulator valve profile.

Fig. 3 is a partial sectional view of a regulator valve according to the present invention.

Fig. 4 is a partial cross-sectional view of another regulator valve of the present invention.

Element numbers:

1 valve seat

11 valve seat molded lines

2 valve disc

21 seal segment profile

22 flow control segment type wire

23 valve disc head profile

3 valve body

4 valve cover

5 valve rod

6 valve disc sleeve

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

Referring to fig. 1-4, in the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, which are merely for convenience of description and simplicity of description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The steam inlet valve of the steam turbine is used for controlling and adjusting high-temperature and high-pressure steam from the boiler so as to adapt to the requirements of starting and output power change of the steam turbine. For an industrial turbine operated by a main pipe system, a full-parameter starting mode is mostly adopted, the pressure before a cold starting valve is almost equal to the rated pressure, and the volume flow of steam is relatively small. If the same steam inlet regulating valve molded line and the same steam inlet flow rate of the unit-system operation steam turbine are adopted, smaller valve opening is needed, the valve opening is often needed to be stabilized below 1mm under the warming-up working condition, a control system is difficult to realize, and the regulating precision of the valve per se cannot meet the starting requirement of the unit, so that the problems of sudden jump of the rotating speed, fast flying and the like can be caused when the unit is started, and the safe and stable operation of the unit is influenced. Therefore, the invention discloses a regulating valve profile structure shown in fig. 1, which comprises a valve disc profile on a valve disc 2 and a valve seat profile 11 on a valve seat 1, and the regulating valve profile structure can be applied to a steam turbine adopting a full-parameter starting mode, has higher flow regulating precision under the working condition of small opening (less than 20 percent opening), and can ensure higher through-flow capacity under the working condition of full opening.

Referring to fig. 1, in the present invention, the valve disc profile is disposed on the valve disc 2 of the regulating valve, the valve disc profile is in a multi-segment form, the valve disc profile includes a sealing segment profile 21 (corresponding to the ab segment in fig. 1), a flow control segment profile 22 (corresponding to the be segment in fig. 1), and a valve disc head profile 23 (corresponding to the downstream segment at point e in fig. 1), which are connected in sequence, and the sealing function and the flow regulating function of the valve are respectively realized by two segments of profiles (the sealing segment profile 21 and the flow control segment profile 22), and the design of the multi-segment profile can more flexibly optimize the regulating characteristics of the valve profile. The seal section molded line 21 may be, for example, a straight line section ab, an included angle α between the straight line section ab and a first direction (a horizontal direction in fig. 1) is between 30 ° and 60 °, the first direction is perpendicular to an axial direction of the valve disc 2 body, and a first mating seal point f is disposed on the seal section molded line 21. As an example, the angle α may be, for example, 30 °, 35 °, 40 °, 45 °, 50 °, 55 ° or 60 °. It will be appreciated that in some embodiments, the seal segment profile 21 may also be, for example, an arc segment on which the first mating seal point f is disposed.

Referring to fig. 1, in the present invention, the valve seat profile 11 has an arc-shaped segment AB, the sealing of the regulating valve is realized by a sealing segment profile of the valve disc profile and the arc-shaped segment AB of the valve seat profile 11, and the arc-shaped segment AB of the valve seat profile 11 has a second matching sealing point F matching and sealing with the first matching sealing point F. As an example, the arc segment AB may be a circular arc line, for example.

Referring to fig. 1, in the present invention, the flow control section type line 22 includes a first cutting section type line bc, an arc section type line cd and a second cutting section type line de, which are connected in sequence, the arc section type line cd has a first end point c and a second end point d, the first cutting section type line bc and the arc section type line cd are tangent to the first end point c, the second cutting section type line de and the arc section type line cd are tangent to the second end point d, the first cutting section type line bc is connected to the sealing section type line 21, and the second cutting section type line de is connected to the valve disc head type line 23.

Referring to fig. 1, in an embodiment of the present invention, the first tangent section bc may be, for example, a straight line section, and the first tangent section bc is parallel to an axial direction of the valve disc 2 body, that is, in fig. 1, the first tangent section bc is a vertical line, a gap n is reserved between the first tangent section bc and the valve seat profile 11, and the size of the gap n may be set reasonably according to requirements; the arc segment type line cd may be, for example, an arc line; the second tangential line de may be, for example, a straight line segment, an included angle β between the second tangential line de and a first direction (a horizontal direction in fig. 1) is between 20 ° and 40 °, the first direction is perpendicular to the axial direction of the valve disc 2 body, and an included angle β between the second tangential line de and the first direction may be, for example, 20 °, 25 °, 30 °, 35 °, or 40 °. Under the working condition of small opening degree, the control of steam inlet flow is realized by the cooperation of a bcd section of a valve disc molded line and an AB section on a valve seat molded line 11, and under the working condition of large opening degree, the control of steam inlet flow is realized by the cooperation of a de section of the valve disc molded line and the AB section on the valve seat molded line 11.

In the invention, the head of the valve disc 2 body can be a straight section or a concave shape, which can effectively reduce the fluctuation generated by steam flow impact during the operation of the regulating valve and improve the stability of the regulating valve. Specifically, fig. 1 shows the valve disc 2 head of the valve disc 2 body as a straight segment, and the valve disc head profile 23 is a horizontal segment.

Fig. 2 shows a comparison graph of flow characteristic curves of the regulating valve profile structure of the present invention and a typical regulating valve profile, and it can be seen from fig. 2 that, compared with the typical regulating valve profile structure in the prior art, the regulating characteristic of the regulating valve profile structure of the present invention fully utilizes the characteristics of the multi-segment profile of the valve disc 2, and has significant advantages: in the region of middle and small opening degrees (within 60 percent of opening degrees), the relationship between the flow and the opening degree of the profile structure of the regulating valve is not simple and linear, but shows the change trend of the slope from small to large, the smaller the slope is, the higher the regulating precision of the valve is, namely the larger the opening degree of the valve is required to reach the same flow; under the working condition of small opening within 20 percent, the slope of the flow characteristic curve of the regulating valve profile structure is minimum, and can reach 1/2 of the slope of the flow characteristic curve of the existing regulating valve profile, so that the problem of poor control stability of a steam turbine adopting a full-parameter starting mode under a warming-up working condition due to the fact that the opening of the valve is too small can be fundamentally solved. The improvement of the regulating precision is at the cost of reducing the through-flow capacity, the through-flow capacity of the regulating valve profile structure is obviously lower than that of the prior art under the working condition of medium and small opening degrees, but the slope of the regulating valve profile structure in the medium opening degree area is in an exponential rising trend, so that the through-flow capacity of the regulating valve profile structure reaches the level of the prior art at about 80% opening degree, namely, the steam inlet regulating valve profile disclosed by the invention has the advantages of high regulating precision of small opening degree and high through-flow capacity of large opening degree.

As shown in fig. 3, the present invention further introduces a regulating valve capable of being used as an intake valve of a steam turbine, the regulating valve includes a valve cover 4, a valve rod 5, a valve disc 2, a valve seat 1, a valve disc sleeve 6 and a valve body 3, and the valve seat 1 and the valve disc 2 are respectively designed by the valve seat profile 11 and the valve disc profile. Specifically, the top of valve disc sleeve 6 with the bottom of valve gap 4 can adopt screw thread fixed connection for example, valve disc 2 accessible valve rod 5 upper and lower gliding connect in valve disc sleeve 6, valve seat 1 be fixed in the play vapour passageway of governing valve and with valve disc 2 matches and corresponds, the lower extreme of valve rod 5 passes in proper order valve gap 4 with the top of valve disc sleeve 6 and stretch into behind the cavity of valve disc sleeve 6 in the top of butterfly valve is connected. By way of example, the valve disc 2 and the valve stem 5 may be of one-piece construction, for example. As an example, the valve body 3 and the valve seat 1 may be of an integral structure, for example.

Referring to fig. 4, the present invention further introduces another regulating valve which can be used as an intake valve of a steam turbine, which is substantially the same as the regulating valve shown in fig. 2 except that an annular groove structure 7 for collecting impurities in steam is disposed on an outer wall of the valve disc 2, and is not described herein again. Referring to fig. 3, the annular groove structure 7 may be disposed on the outer wall of the valve disc 2 at a position close to the seal segment line of the valve seat line 11, for example, and the annular groove structure 7 can prevent the seal surfaces (the seal surface of the valve disc 2 and the seal surface of the valve seat 1) of the regulating valve from being damaged by erosion of hard particles, which may result in leakage of the regulating valve.

In conclusion, the profile structure of the regulating valve is suitable for the steam turbine adopting the full-parameter starting mode, has higher flow regulating precision under the working condition of small opening (below 20 percent opening), and can ensure higher through-flow capacity under the working condition of full opening, namely has the advantages of high regulating precision of small opening and high through-flow capacity of large opening; according to the valve profile structure of the regulating valve, the valve disc profile is in a multi-section form, the sealing effect and the flow regulating effect of the valve are realized through two sections of profiles (the sealing section and the flow control section) respectively, and the regulating characteristic of the valve profile can be more flexibly optimized through the design of the multi-section profile; according to the regulating valve profile structure, the head part of the valve disc is in a flat section or an inward concave shape, so that fluctuation generated by steam flow impact during the operation process of the regulating valve can be effectively reduced, and the stability of the regulating valve is improved; the outer wall of the valve disc of the regulating valve adopting the regulating valve molded line is provided with the annular groove structure for collecting impurities in steam, so that the sealing surfaces (the sealing surface of the valve disc and the sealing surface of the valve seat) of the regulating valve can be prevented from being damaged by erosion of hard particles, and the leakage of the regulating valve can be prevented.

In the description herein, numerous specific details are provided, such as examples of components and/or methods, to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that an embodiment of the invention can be practiced without one or more of the specific details, or with other apparatus, systems, assemblies, methods, components, materials, parts, and/or the like. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of embodiments of the invention.

The above description of illustrated embodiments of the invention, including what is described in the abstract of the specification, is not intended to be exhaustive or to limit the invention to the precise forms disclosed herein. While specific embodiments of, and examples for, the invention are described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the present invention, as those skilled in the relevant art will recognize and appreciate. As indicated, these modifications may be made to the present invention in light of the foregoing description of illustrated embodiments of the present invention and are to be included within the spirit and scope of the present invention.

The systems and methods have been described herein in general terms as the details aid in understanding the invention. Furthermore, various specific details have been given to provide a general understanding of the embodiments of the invention. One skilled in the relevant art will recognize, however, that an embodiment of the invention can be practiced without one or more of the specific details, or with other apparatus, systems, assemblies, methods, components, materials, parts, and/or the like. In other instances, well-known structures, materials, and/or operations are not specifically shown or described in detail to avoid obscuring aspects of embodiments of the invention.

Thus, although the present invention has been described herein with reference to particular embodiments thereof, a latitude of modification, various changes and substitutions are intended in the foregoing disclosures, and it will be appreciated that in some instances some features of the invention will be employed without a corresponding use of other features without departing from the scope and spirit of the invention as set forth. Thus, many modifications may be made to adapt a particular situation or material to the essential scope and spirit of the present invention. It is intended that the invention not be limited to the particular terms used in following claims and/or to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Accordingly, the scope of the invention is to be determined solely by the appended claims.

Claims

1. A regulator valve profile, said regulator valve comprising a valve disc and a valve seat, said regulator valve profile comprising:

the valve seat molded line is arranged on the valve seat;

2. The regulator valve profile structure according to claim 1, wherein the seal segment profile has a first mating seal point thereon; the valve seat type line is provided with a second matching sealing point which is matched and sealed with the first matching sealing point.

3. The profile structure of a regulating valve according to claim 1, wherein the seal section profile is a straight-line section or an arc-shaped section, if the seal section profile is a straight-line section, an included angle between the straight-line section and a first direction is between 30 ° and 60 °, and the first direction is perpendicular to an axial direction of the valve disc body.

4. The regulator valve profile structure according to claim 1, wherein the first cut segment profile comprises a straight segment, the first cut segment profile being parallel to an axial direction of the valve disc body.

5. The regulator valve profile structure according to claim 1, wherein a gap is reserved between the first segment profile and the seat profile.

6. The regulator valve profile structure of claim 1, wherein the second tangential line segment comprises a straight line segment, the second tangential line segment having an angle between 20 ° and 40 ° with respect to a first direction, the first direction being perpendicular to the axial direction of the valve disc body.

7. The regulator valve profile structure of claim 1, wherein the valve disc head of the valve disc body comprises a straight section or is concave in shape.

8. A regulator valve profile according to any of claims 1 to 7, wherein the valve seat profile comprises a circular arc.

9. A regulator valve, comprising:

a valve body;

a valve seat having a seat profile;

a valve stem; and

a valve cover;

10. The regulator valve of claim 9 wherein the outer wall of the valve disc is provided with an annular groove.