Anti-erosion cage type single-seat valve

Abstract

The utility model relates to an anti-erosion cage type single-seat valve, which comprises a valve body, an upper valve cover, a valve core, a valve rod, an inner sleeve, an outer sleeve and a cage sleeve type valve seat, a cage sleeve type valve seat is arranged at the communication part of the inlet runner and the outlet runner in the valve body, and a plurality of throttling holes I are formed in the lower part of the cage sleeve type valve seat; a main runner is formed between the cage sleeve type valve seat and the valve core; an inner sleeve is arranged on the periphery of the valve element and provided with a plurality of second throttling holes. An outer sleeve is arranged on the outer side of the inner sleeve and provided with a plurality of third throttling holes. And the inner sleeve, the outer sleeve and the cage sleeve type valve seat are pressed and fixed in the valve body through the upper valve cover. According to the cage type single-seat valve, under the condition that flow characteristics are not affected, the number and the hole diameter of the throttling holes in the outer sleeve and the cage type valve seat are optimized, and the number and the diameter of the protruding structures on the outer side of the valve element are optimized, so that the erosion resistance of the cage type single-seat valve is effectively improved.

Description

Technical Field

[0001] The utility model relates to a cage type single seat valve, in particular to an erosion resistant cage type single seat valve. Background Art

[0002] Single-seat valves, also known as single-seat regulating valves, feature a single valve core and seat within the valve body. Opening and closing can be achieved by simply changing the positional relationship between the valve core and the seat. Single-seat valves have the advantage of low leakage, but their disadvantage is that the medium exerts a large unbalanced force on the valve core, resulting in a small allowable pressure differential. Therefore, single-seat valves are only suitable for clean media with strict leakage requirements and low pressure differentials. Conversely, they are not suitable for unclean media with high pressure differentials. Single-seat regulating valves are primarily categorized by structure into four types: single-seat, sleeve-type, double-seat, and cage-type.

[0003] Single-seat valves are susceptible to erosion and wear issues under high pressure differentials, high flow rates, and two-phase flow conditions with solid particles, leading to valve trim failure. High-speed fluid movement can carry solid particles that impact the valve trim surface, causing significant erosion and wear on the valve seat and valve core. This can lead to regulation failure and loss of operating capacity, compromising the safety and reliability of the operating system. Compared to other single-seat valve structures, the cage-type single-seat control valve utilizes a multi-stage pressure-reducing design that effectively slows fluid flow and suppresses erosion.

[0004] In nature, some organisms continuously evolve their structures to adapt to harsh environments, which has broadened the scope of engineering design. Observations of red willow bark revealed that its irregular convex hull structure significantly enhances resistance to extreme erosion. By studying the biomimetic effects of this structure, a single-seat valve core surface design was developed. This design improves the valve trim's resistance to erosion in solid-liquid two-phase flow, thereby extending the valve's service life.

[0005] Factors such as flow velocity, pressure drop, and streamline trajectory within a single-seat valve affect its erosion resistance. Therefore, designing multi-stage pressure-reducing elements and biomimetic anti-erosion structures within the flow path is essential. Optimizing the number and diameter of orifices on the throttling sleeve, as well as the number and diameter of biomimetic convex hulls, can minimize erosion within the valve without affecting flow characteristics. This is crucial for ensuring the safe and stable operation of industrial production equipment. Summary of the Invention

[0006] The utility model provides an erosion-resistant cage-type single-seat valve, in which an inner sleeve, an outer sleeve, a valve core and a cage-type valve seat are arranged in the valve body of the single-seat valve. Without affecting the flow characteristics, the erosion resistance of the cage-type single-seat valve is effectively improved by optimizing the number and aperture of throttling holes on the outer sleeve and the cage-type valve seat, as well as optimizing the number and diameter of protruding structures on the outer side of the valve core.

[0007] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0008] When unclamping said control button, under the effect of the compression spring and the bubble holding vessel internal pressure that shaves, combine closely in the interior edge of valve gap and sealing load chamber, and burble goes out control valve thereby control is shaved.

[0009] The matching section between the lower part of the valve core and the cage-type valve seat is a multi-section variable diameter structure, and the diameter of the multi-section variable diameter structure gradually decreases from top to bottom; specifically, the multi-section variable diameter structure is composed of a large-taper cone, a small-taper cone and a hemisphere in sequence, and the connections between the three are smoothly transitioned; multiple protrusion structures are evenly arranged along the circumferential direction on the outer sides of the large-taper cone and the hemisphere.

[0010] Gaskets are provided at the contact surfaces of the outer sleeve, the inner sleeve and the cage-type valve seat.

[0011] The first throttle hole is a stepped hole, and the hole diameter close to the outer side is larger than the hole diameter close to the inner side.

[0012] The throttle hole three and the throttle hole two are arranged alternately.

[0013] The protrusion structure is a hemispherical protrusion.

[0014] Compared with the prior art, the beneficial effects of the present invention are:

[0015] 1) Drawing on the special structure of red willow bark, which has strong erosion resistance in nature, a bionic raised structure is designed on the outside of the valve core to significantly enhance its erosion suppression effect;

[0016] 2) Add a cage-type valve seat with a porous cage structure at the bottom of the valve seat, and set a porous outer sleeve outside the inner sleeve to achieve multi-stage pressure reduction and speed regulation functions;

[0017] 3) The valve core is located in an inner sleeve with a porous structure. As the valve core moves upward, more and more throttling holes are exposed on the inner sleeve. Corresponding to the various openings of the single-seat valve, while meeting the flow characteristics, the throttling area of ​​the inner sleeve can be minimized, thereby maximizing pressure reduction and speed regulation.

[0018] 4) When optimizing the structure of the anti-erosion cage single-seat valve, the utility model uses Design-Expert software for experimental design and data analysis, and uses the Box-Behnken response surface optimization method, which has high optimization efficiency and can accurately approximate the optimal value of the response surface;

[0019] 5) Through the erosion characteristics analysis of the optimized anti-erosion cage single-seat valve, it can be proved that after the cage valve seat, porous outer sleeve and valve core with a convex structure are set, the erosion of the valve trim is significantly improved and the erosion rate is significantly reduced; when the optimized single-seat valve is fully opened, the erosion rate is reduced from 8.0×10 -2 kg / (m 2 ·s) is reduced to 1.52×10 -2 kg / (m 2 ·s), good erosion resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a main sectional view of an erosion-resistant cage-type single-seat valve described in the utility model.

[0021] Figure 2 It is a three-dimensional cross-sectional view of an erosion-resistant cage-type single-seat valve described in the utility model.

[0022] Figure 3 It is a partial structural diagram of the valve core of the utility model.

[0023] Figure 4 This is a flow field velocity distribution diagram when the single-seat valve in the embodiment of the utility model is fully opened.

[0024] Figure 5 This is a flow field pressure distribution diagram when the single-seat valve in the embodiment of the present utility model is fully opened.

[0025] Figure 6 It is a Box-Behnken response surface optimization flow chart in the embodiment of the present utility model.

[0026] Figure 7 This is a distribution diagram of the erosion rate when the single-seat valve is fully opened before optimization in the embodiment of the utility model.

[0027] Figure 8 This is a distribution diagram of the erosion rate when the optimized single-seat valve is fully opened in the embodiment of the utility model.

[0028] In the figure: 1-upper valve cover; 2-valve stem; 3-valve body; 4-inner sleeve; 5-valve core; 51. protrusion structure; 6-outer sleeve; 7-cage-type valve seat. DETAILED DESCRIPTION

[0029] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings:

[0030] like Figure 1 、 Figure 2 As shown, the utility model of an erosion-resistant cage-type single-seat valve includes a valve body 3, an upper valve cover 1, a valve core 5 and a valve stem 2; it also includes an inner sleeve 4, an outer sleeve 6 and a cage-type valve seat 7; the valve core 5 and the valve stem 2 are an integral structure; a fluid inlet is provided on one side of the valve body 3 to form an inlet flow channel, and a fluid outlet is provided on the other side to form an outlet flow channel, the top of the inlet flow channel and the bottom of the outlet flow channel are connected in the middle of the valve body 3, and a cage-type valve seat 7 is provided at the connection point; the lower part of the cage-type valve seat 7 is located in the inlet flow channel and is circumferentially A plurality of throttling holes are provided; an opening is provided at the top of the cage-type valve seat 7, which cooperates with the lower end of the valve core 5 to form a main flow channel; an inner sleeve 4 is provided above the cage-type valve seat 7 and on the periphery of the valve core 5, and a plurality of throttling holes are provided circumferentially at the lower part of the inner sleeve 4 at the height corresponding to the outlet flow channel; an outer sleeve 6 is provided on the outer side of the lower part of the inner sleeve 4, and a plurality of throttling holes are provided circumferentially; the outer sleeve 6 is located between the inner sleeve 4 and the cage-type valve seat 7; the inner sleeve 4, the outer sleeve 6 and the cage-type valve seat 5 are pressed and fixed in the valve body 3 by the upper valve cover 1.

[0031] The matching section between the lower part of the valve core 5 and the cage-type valve seat 7 is a multi-stage variable diameter structure, and the diameter of the multi-stage variable diameter structure gradually decreases from top to bottom; specifically, the multi-stage variable diameter structure is composed of a large-taper cone, a small-taper cone and a hemisphere in sequence, and the connections between the three are smoothly transitioned; a plurality of protrusion structures 51 are evenly arranged along the circumferential direction on the outer side of the large-taper cone and the hemisphere.

[0032] Gaskets are provided at the contact surfaces of the outer sleeve 6 , the inner sleeve 4 and the cage-type valve seat 7 .

[0033] The first throttle hole is a stepped hole, and the hole diameter close to the outer side is larger than the hole diameter close to the inner side.

[0034] The throttle hole three and the throttle hole two are arranged alternately.

[0035] The protrusion structure 51 is a hemispherical protrusion.

[0036] The erosion-resistant cage-type single-seat valve described in this utility model is optimized based on a conventional single-seat valve. The optimization design process is as follows:

[0037] 1) Develop an optimization strategy based on the premise of satisfying the flow characteristics of the single-seat valve: the optimization target is the valve trim erosion rate, that is, to minimize the valve trim erosion rate; the number and aperture of throttle holes 1 and throttle holes 3, as well as the number and diameter of the protrusions on the valve core are used as design parameter variables;

[0038] 2) Sensitivity analysis of design parameter variables on the optimization objective, that is, analyzing the degree of influence of each design parameter variable on the optimization objective: by adjusting the value range of each parameter, it is determined that each parameter has a significant impact on the optimization objective;

[0039] 3) Using finite element simulation to provide data samples for erosion rate tests: Design-Expert software was used for experimental design and data analysis, and the Box-Behnken response surface optimization method was used to establish a quadratic polynomial fitting model, i.e., a second-order design model;

[0040] 4) The second-order design model is used to accurately approximate the optimal value of the response surface within the set investigation range, and the items that have no significant impact on the response value are eliminated to obtain the optimal parameter matching solution.

[0041] like Figure 1 、 Figure 2 As shown, a fluid inlet is provided on the left side of the valve body 1 (in the direction shown in the figure), and a fluid outlet is provided on the right side of the valve body 1, adopting a bottom-in and side-out circulation form. The cage-type valve seat 7 is provided in the valve body 3. The cage-type valve seat 7 is a traditional valve seat with a porous cage structure added to the lower part. When the valve stem 2 moves upward under the action of the actuator, the valve core 5 moves in the direction away from the opening on the cage-type valve seat 7 and forms different openings. The fluid passes through the throttle hole 1 on the cage-type valve seat 7, the gap (main flow channel) between the valve core 5 and the cage-type valve seat 7, the throttle hole 2 on the inner sleeve 4 and the throttle hole 3 on the outer sleeve 6 in sequence, and finally flows out from the fluid outlet of the valve body 1. After passing through the above-mentioned throttling element, the fluid forms a flow characteristic of step-by-step pressure reduction, thereby achieving speed regulation. The purpose of this utility model is to reduce the erosion of valve trim without affecting the flow characteristics of the single-seat valve.

[0042] The lower part of the valve core 5 adopts a multi-stage variable diameter structure, which consists of two sections of conical rotating bodies and a hemispherical body. As the valve core 5 moves upward, the cross-sectional diameter of the valve core 5 that matches the top opening of the cage-type valve seat 7 becomes smaller and smaller, and the flow area of ​​the main flow channel formed between the two becomes larger and larger. That is, by adjusting the cross-sectional diameter of each section of the multi-stage variable diameter structure on the valve core 5, the flow characteristics can be controlled. At the same time, when the flow field velocity increases (such as Figure 4 As shown), the pressure will drop sharply (as shown Figure 5 shown).

[0043] The valve core 5 adopts a bionic design, drawing on the red willow bark with strong erosion resistance in nature, and a convex structure 51 (such as Figure 3 These protruding structures 51 directly affect the streamline trajectory in the flow field, and can significantly reduce the erosion of the fluid medium on the valve trim.

[0044] The main body of the valve core 5 is a cylindrical structure, built into the inner sleeve 4. There are multiple throttle holes 2 distributed on the inner sleeve 4. As the valve core 5 moves upward, the number of throttle holes 2 on the inner sleeve 4 becomes more and more exposed, corresponding to the different openings of the single-seat valve. Under the premise of meeting the flow characteristics, minimizing the throttling area of ​​the inner sleeve 4 can maximize the pressure reduction and speed regulation (such as Figure 4 、 Figure 5 shown).

[0045] The cage-type valve seat 7 is a traditional valve seat with a porous cage structure added to the lower part to achieve the functions of pressure reduction and speed regulation (such as Figure 4 、 Figure 5 shown).

[0046] The outer sleeve 6 is arranged outside the inner sleeve 4 and fixed between the inner sleeve 4 and the cage valve seat 7. The outer sleeve 6 adopts a porous structure. When the fluid flows through the throttle hole 3 on the outer sleeve 6, pressure reduction and speed regulation can also be achieved (such as Figure 4 、 Figure 5 shown).

[0047] The following embodiments are implemented based on the technical solution of the present utility model, and provide detailed implementation methods and specific operating processes, but the protection scope of the present utility model is not limited to the following embodiments.

[0048] [Example]

[0049] In this embodiment, the cross-sectional view of the erosion-resistant cage single-seat valve (single-seat valve for short) is as follows: Figure 1 、 Figure 2 As shown, the engineering diameter of the single-seat valve is DN50, the valve core stroke is 25mm, and the flow capacity C v A linear flow characteristic with a value of 10. The inlet fluid pressure is 9.34 MPa and the outlet fluid pressure is 0.5 MPa.

[0050] In this embodiment, the erosion-resistant caged single-seat valve consists of an upper bonnet 1, a valve stem 2, a valve core 5, a valve body 3, an inner sleeve 4, an outer sleeve 6, and a caged valve seat 7. The caged valve seat 7 is secured within the valve body 3 under the pressure of the upper bonnet 1 and the inner and outer sleeves 4 and 6. A gasket is provided between the inner and outer sleeves 4 and 6, and the caged valve seat 7, to prevent leakage that could affect flow characteristics.

[0051] The porous cage structure of the cage-type valve seat 7 sinks into the inlet flow channel at the bottom of the valve body 3, and multiple stepped holes, namely throttle holes 1, are evenly distributed along the circumference thereof, through which one-stage pressure reduction and speed regulation are achieved.

[0052] The multi-stage reducing structure at the bottom of the valve core 5 contacts the side of the top opening of the caged valve seat 7. When the two are tightly fitted, the single-seat valve is fully closed. When the valve stem 2 moves upward under the influence of the external actuator, an opening is formed between the multi-stage reducing structure at the bottom of the valve core 5 and the opening of the caged valve seat 7, opening the main flow path. As the valve core 5 gradually moves upward, the cross-sectional diameter of the multi-stage reducing structure decreases, and the flow area of ​​the main flow path between the valve core 5 and the caged valve seat 7 increases. Therefore, the flow characteristics can be controlled by adjusting the cross-sectional diameter of each segment of the multi-stage reducing structure.

[0053] The inner sleeve 4 is positioned between the upper bonnet 1 and the caged valve seat 7. The valve core 5 is located within the inner sleeve 4. As the valve core 5 moves upward, the throttle hole 2 at the bottom of the inner sleeve 4 is gradually exposed, increasing the flow area. The outer sleeve 6 is located outside the inner sleeve 4, and the two are arranged concentrically. The outer sleeve 6 is axially fixed between the inner sleeve 4 and the caged valve seat 7. The outer sleeve 6 adopts a porous structure.

[0054] The fluid first flows through the caged valve seat 7, achieving a first-stage pressure reduction and speed regulation. It then flows upward through the gap between the valve core 5 and the caged valve seat 7. As the valve core 5 moves upward, the flow characteristics of the single-seat valve are controlled by varying the cross-section diameters at different locations within the multi-stage variable diameter structure.

[0055] When the flow area is sharply reduced, the fluid flow rate will increase significantly and a certain pressure drop will occur. At this time, the erosion of the multi-stage variable diameter structure at the bottom of the valve core 5 is very serious. The utility model draws on the special structure of the red willow bark with strong erosion resistance in nature, and designs a bionic raised structure 51 (such as Figure 3 These protrusions 51 are located at the position of the valve core 5 most significantly affected by erosion, directly affecting the streamline trajectory in the flow field, and can significantly reduce the erosion of the fluid medium on the valve trim.

[0056] The main body of the valve core 5 is a cylindrical structure, embedded in the inner sleeve 4. Multiple throttle holes 2 are distributed in the lower portion of the inner sleeve 4. As the valve core 5 moves upward, more and more throttle holes 2 on the inner sleeve 4 are exposed, which can coordinately control the flow characteristics of the single-seat valve and achieve significant pressure reduction and speed regulation effects.

[0057] Finally, the fluid flows through the throttle hole 3 of the outer sleeve 6 and converges into the outlet flow channel. The throttle hole 3 of the outer sleeve 6 also forms a pressure reduction and speed regulation process (the flow field velocity and pressure distribution when fully open are as follows Figure 4 、 Figure 5 shown).

[0058] In this embodiment, the optimization design process of the erosion-resistant cage-type single-seat valve is as follows:

[0059] 1) Establish a three-dimensional simulation model of the erosion-resistant cage single-seat valve, such as Figure 2 As shown in the figure. Based on finite element simulation analysis of the erosion rate of the internal flow field, an initial finite element model of the single-seat valve was established. A mixed hexahedral and tetrahedral mesh was created, and the mesh near the sealing surface was densified. Finite element mesh independence experiments were conducted to determine the number of meshes to be divided. After setting boundary conditions, a simulation analysis of the erosion rate of the single-seat valve was performed to obtain the optimized basic data.

[0060] 2) Taking the single-seat valve with a front-to-rear pressure difference of 8.84 MPa as an example, the valve trim erosion rate is taken as the optimization target (i.e., minimizing the valve trim erosion rate), and the number and diameter of the throttle hole three of the outer sleeve and the throttle hole one of the cage-type valve seat, as well as the number and diameter of the protrusion structure on the outer side of the valve core, a total of six parameters are used as design parameter variables.

[0061] 3) Analyze the sensitivity of the design parameter variables to the optimization target, that is, analyze the influence of each design parameter variable on the optimization target, and by adjusting the value range of the six parameters, determine whether the six parameters have a significant impact on the optimization target.

[0062] 4) Using the data samples provided by the finite element simulation erosion rate test, Design-Expert software was used for experimental design and data analysis, and the Box-Behnken response surface optimization method was used to establish a quadratic polynomial fitting model, namely the second-order design model.

[0063] 5) Using the second-order design model, the optimal value of the response surface is accurately approximated within the set investigation range, and the items that have no significant impact on the response value are eliminated to obtain the optimal parameter matching solution. The simulation design process is as follows: Figure 6 shown.

[0064] The optimal parameter matching solution obtained in this embodiment is as follows:

[0065]

[0066] In order to verify the anti-erosion performance of the anti-erosion cage single-seat valve after parameter optimization, the erosion rates of the main valve internal components were simulated and compared under the same working conditions according to the structural parameter models before and after optimization. Figure 7 To optimize the erosion rate distribution of the front valve core; Figure 8 The erosion rate distribution of the optimized valve core is shown in Figure 2. It can be seen that after adopting the optimized structure of the utility model, the erosion of the valve core is significantly improved and the erosion rate is significantly reduced. After optimization, the erosion rate at full opening is reduced from 8.00×10 -2 kg / (m 2 ·s) is reduced to 1.52×10 -2 kg / (m 2 ·s), good anti-erosion effect.

[0067] Conclusion: The erosion-resistant caged single-seat valve designed using the optimization design method described in this utility model exhibits excellent erosion resistance. This optimization design method provides an optimal parameter combination for the third orifice on the outer sleeve, the first orifice on the caged valve seat, and the raised structure on the valve core, improving erosion resistance without affecting the flow characteristics of the single-seat valve.

[0068] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the present invention can make equivalent replacements or changes based on the technical solution and inventive concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An erosion-resistant cage-type single-seat valve, comprising a valve body, an upper valve cover, a valve core and a valve stem; characterized in that: The throttle body is located at the bottom of the valve body, and the throttle body is located at the bottom of the valve body. The throttle body is located at the bottom of the valve body, and the throttle body is located at the bottom of the valve body. The throttle body is located at the bottom of the valve body, and the throttle body is located at the bottom of the valve body. The throttle body is located at the bottom of the valve body, and the throttle body is located at the bottom of the valve body. The throttle body is located at the bottom of the valve body, and the throttle body is located at the bottom of the valve body. The throttle body is located at the bottom of the valve body.

2. The erosion-resistant cage-type single-seat valve according to claim 1, characterized in that: The matching section between the lower part of the valve core and the cage-type valve seat is a multi-section variable diameter structure, and the diameter of the multi-section variable diameter structure gradually decreases from top to bottom; specifically, the multi-section variable diameter structure is composed of a large-taper cone, a small-taper cone and a hemisphere in sequence, and the connections between the three are smoothly transitioned; multiple protrusion structures are evenly arranged along the circumferential direction on the outer sides of the large-taper cone and the hemisphere.

3. The erosion-resistant cage-type single-seat valve according to claim 1, characterized in that: Gaskets are provided at the contact surfaces of the outer sleeve, the inner sleeve and the cage-type valve seat.

4. The erosion-resistant cage-type single-seat valve according to claim 1, characterized in that: The first throttle hole is a stepped hole, and the hole diameter close to the outer side is larger than the hole diameter close to the inner side.

5. The erosion-resistant cage-type single-seat valve according to claim 1, characterized in that: The throttle hole three and the throttle hole two are arranged alternately.

6. The erosion-resistant cage-type single-seat valve according to claim 2, characterized in that: The protrusion structure is a hemispherical protrusion.

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