Control valves and control systems for control valves

Abstract

The present invention relates to the field of valve technology, and discloses a regulating valve and a control system for the regulating valve, wherein the regulating valve comprises a valve seat (10), at least three valve plates (20), and a driving mechanism for driving the valve plates (20) to move, wherein the valve plates (20) are arranged in the valve seat (10) and jointly define a flow channel through hole (30), wherein at least two of the valve plates (20) can move so that the size of the flow channel through hole (30) changes in at least two non-parallel directions, thereby adjusting the area of ​​the flow channel through hole (30). The regulating valve provided in the present application can effectively prevent blockage when conveying gas-solid two-phase fluids such as powders.

Description

Technical Field

[0001] The present invention relates to the field of valve technology, and in particular to a regulating valve and a control system of the regulating valve. Background Art

[0002] There are two main adjustment schemes for pulverized coal flow regulating valves. The first one is a needle valve-like structure, which changes the size of the annular gap between the valve core and the valve seat by adjusting the formation of the valve stem, thereby changing the flow area. However, due to the particularity of the gas-solid two-phase flow of powder during pneumatic conveying, when the sealing annular gap is reduced to a certain critical value, cluster bridging will occur in the gas-solid two-phase flow, which will lead to valve blockage.

[0003] The second method is to change the opening area of ​​the valve core by the up and down movement of the valve stem, thereby changing the flow area. The opening mode of the valve core is mostly U-shaped or V-shaped. In this structure, when the valve opening reaches a certain degree, the regulating effect on the flow rate basically disappears. For example, when the valve opening needs to be reduced, the valve body's size in one direction is rapidly reduced to reduce the valve opening (for example, the flow channel suddenly shrinks in the width direction, causing the flow channel to become slender), which is also easy to cause blockage. Summary of the invention

[0004] The purpose of the present invention is to provide a regulating valve in order to overcome the problem in the prior art that there is no regulating valve suitable for conveying powder.

[0005] In order to achieve the above-mentioned objectives, the present invention provides a regulating valve on one hand, which includes a valve seat, at least three valve plates and a driving mechanism for driving the valve plates to move, wherein the valve plates are arranged in the valve seat and jointly define a flow channel hole, wherein at least two of the valve plates can move so that the size of the flow channel hole changes in at least two non-parallel directions, thereby adjusting the area of ​​the flow channel hole.

[0006] Through the above technical solution, at least two of the at least three valve plates can be moved, so that the size of the flow channel through hole 30 changes in at least two non-parallel directions. When adjusting the area of ​​the flow channel through hole 30, it can be ensured that the size of the flow channel through hole in at least two directions changes. For the gas-solid two-phase flow of powder, blockage can be effectively prevented.

[0007] Optionally, the valve plate includes two first valve plates that are oppositely disposed and two second valve plates that are oppositely disposed, so that the flow channel through hole is formed as a rectangular through hole.

[0008] Optionally, two of the first valve plates are located on a first plane and at least one of the first valve plates can move in the first plane, two of the second valve plates are located on a second plane and at least one of the second valve plates can move in the second plane, the first plane and the second plane are both perpendicular to the axis of the flow channel through hole, and the first plane and the second plane are not coplanar.

[0009] Optionally, the movement of at least one of the first valve plates and at least one of the second valve plates enables the flow channel through hole to always remain a square through hole.

[0010] Optionally, the valve seat includes a side wall portion and an orifice plate portion perpendicular to the side wall portion, the orifice plate portion includes three orifice plates parallel to each other and having through holes in the middle, the side wall portion is arranged parallel to the axis of the flow channel through hole, the orifice plate is perpendicular to the side wall portion, and the thickness dimension of the valve plate matches the gap dimension between the two orifice plates so as to be arranged between two adjacent orifice plates.

[0011] Optionally, the regulating valve comprises a sealing ring, a groove is formed on the surface of the orifice plate portion and / or the surface of the valve plate, and the sealing ring is arranged in the groove.

[0012] Optionally, the regulating valve includes a valve stem arranged on the valve plate, the valve seat has a valve stem through hole, the valve stem can pass through the valve stem through hole to extend to the outside of the valve seat, the driving mechanism is arranged on the outer wall of the valve seat, and the output end of the driving mechanism is connected to the valve stem to drive the valve stem to move.

[0013] Optionally, the driving mechanism comprises a motor, a gear is provided at the output end of the motor, and the valve stem is a rack matched with the gear so that the motor can drive the rack to move.

[0014] Optionally, the two first valve plates are located on a first plane, the two second valve plates are located on a second plane, and the first plane and the second plane are not coplanar.

[0015] Optionally, the valve seat includes a side wall portion and an orifice plate portion perpendicular to the side wall portion, the orifice plate portion includes three orifice plates parallel to each other and having through holes in the middle, the side wall portion is arranged parallel to the axis of the flow channel through hole, the orifice plate is perpendicular to the side wall portion, and the thickness dimension of the valve plate matches the gap dimension between the two orifice plates so as to be arranged between two adjacent orifice plates.

[0016] Optionally, the regulating valve comprises a sealing ring, a groove is formed on the surface of the orifice plate portion and / or the surface of the valve plate, and the sealing ring is arranged in the groove.

[0017] Optionally, the plate surface of the valve plate facing the incoming material is an inclined surface, and the inclined surface is configured to gradually sink in a direction gradually approaching the flow channel through hole.

[0018] A second aspect of the present invention provides a control system for a regulating valve, the control system for the regulating valve comprising a controller and the regulating valve as described above, wherein the controller is electrically connected to the driving mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of a regulating valve according to a preferred embodiment of the present application;

[0020] Figure 2 yes Figure 1 A schematic diagram of a regulating valve with the valve seat omitted, showing the valve plate located in the valve seat;

[0021] Figure 3 yes Figure 1 A cross-sectional view of a regulating valve;

[0022] Figure 4 yes Figure 1 A perspective view of a regulating valve.

[0023] Description of Reference Numerals

[0024] 10. Valve seat; 20. Valve plate; 30. Flow channel through hole; 40. Valve stem; 50. Motor;

[0025] 21. first valve plate; 22. second valve plate; 11. side wall; 12. orifice plate DETAILED DESCRIPTION

[0026] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0027] The present invention provides a regulating valve, such as Figure 1 As shown, the regulating valve includes a valve seat 10, at least three valve plates 20 and a driving mechanism for driving the valve plates 20 to move, wherein the valve plates 20 are arranged in the valve seat 10 and jointly define a flow channel hole 30, wherein at least two of the valve plates 20 can move so that the size of the flow channel hole 30 changes in at least two non-parallel directions, thereby adjusting the area of ​​the flow channel hole 30.

[0028] At least two of the three valve plates can move in a plane perpendicular to the axis of the flow channel through hole 30, so that the size of the flow channel through hole 30 changes in at least two non-parallel directions. When adjusting the area of ​​the flow channel through hole 30, it can be ensured that the size of the flow channel through hole in at least two directions changes, which can effectively prevent the possibility of blockage for the gas-solid two-phase flow of powder. The non-parallel directions refer to that the two directions are neither the same nor opposite.

[0029] Among them, the movable valve plate 20 can move in planes that are not parallel to each other, but there will be requirements for the size of the valve seat 10 in the axial direction along the flow channel through hole 30. The present application preferably moves in a plane perpendicular to the axis of the flow channel through hole 30, so that the valve plate 20 will not move in the axial direction of the flow channel through hole.

[0030] In one embodiment, the regulating valve includes three valve plates, the flow channel through hole is a triangular through hole, two of the three valve plates can move, and the two movable valve plates are located on different planes and these planes are perpendicular to the axis of the flow channel through hole 30, so that at least two sides of the triangle change in length; in another embodiment, the regulating valve includes four valve plates, the flow channel through hole is a parallelogram, and for the parallelogram, the valve plates 20 constituting its two adjacent sides should be moved, so as to ensure movement in two non-parallel directions, so that changes in two non-parallel directions occur in the flow channel through hole 30; in addition, the regulating valve may include more valve plates to form other regular or irregular shapes, which are all within the scope of protection of the present application.

[0031] like Figure 1 and Figure 2 As shown, in a preferred embodiment of the present application, the regulating valve includes four valve plates, and the valve plates include a pair of first valve plates 21 and a pair of second valve plates 22, thereby forming a rectangular flow channel hole 30, wherein at least one first valve plate 21 and at least one second valve plate 22 can move in a plane, so that the flow channel hole 30 always remains in the form of a rectangular orifice plate. In a more preferred embodiment, the movement of the first valve plate 21 and the second valve plate 22 allows the flow channel hole 30 to always remain in a square shape. When the area of ​​the flow channel hole is reduced, the size of each side of the flow channel hole 30 is reduced synchronously. This flow channel hole 30 that always remains in a square shape can ensure that the heterogeneous flow of the gas-solid two-phase powder such as powder will not be blocked due to the rapid reduction of the size of the flow channel hole in a certain direction.

[0032] The plate surface of the valve plate 20 facing the incoming material is configured as an inclined surface, and the inclined surface is configured to gradually sink in the direction close to the flow channel through hole 30. When the incoming material on the supply side passes through the flow channel through hole 30, it can gradually move toward the middle along the inclined surface, thereby playing a role in guiding the incoming material.

[0033] Figure 3 is a cross-sectional view of a regulating valve according to a preferred embodiment of the present application, wherein the direction of the section line is parallel to the arrangement direction of the two second valve plates 22. Figure 3 In the structure shown, the first valve plate 21 is located on a first plane, and the second valve plate 22 is located on a second plane. The first plane and the second plane are both perpendicular to the axis of the flow channel through hole 30 but are not coplanar with each other. Therefore, the first valve plate 21 and the second valve plate 22 are staggered in height to avoid interference in the movement of the first valve plate 21 and the second valve plate 22.

[0034] In one embodiment of the present application, guide rails or slide rails are arranged at different height positions inside the side wall portion 11, and the first valve plate 21 and the second valve plate 22 are respectively installed on rails at different height positions, so that the first valve plate 21 and the second valve plate 22 are staggered from each other in height positions.

[0035] In the preferred embodiment of this application, continue to refer to Figure 3 The valve seat 10 comprises a side wall portion 11 and an orifice plate portion perpendicular to the side wall portion 11, the orifice plate portion comprises three orifice plates 12 with through holes in the middle, wherein the side wall portion 11 is arranged parallel to the axis of the flow channel through hole 30, the orifice plate 12 is arranged perpendicular to the side wall portion 11, and the valve plate 20 is arranged between two adjacent orifice plates 12, so that the first valve plate 21 and the second valve plate 22 can be arranged at different height positions.

[0036] Among them, the through holes in the middle of the three orifice plates 12 are exactly the same and completely correspond to each other in the axial direction of the flow channel through hole 30. The through holes formed on the orifice plates 12 should fully accommodate the maximum opening designed for the flow channel through hole 30 in shape and size, so that the flow channel through hole 30 will not be blocked at any opening of the flow channel through hole 30.

[0037] The thickness of the valve plate 20 should match the size of the gap between the two orifice plates 12. The advantage of this structure lies in the surface contact between the orifice plate 12 and the valve plate 20. On the one hand, the valve plate 20 can be arranged to fit the two orifice plates 12 at the same time for movement, maintaining continuous surface contact between the orifice plate 12 and the valve plate 20 to form a stable sliding connection, so that the movement of the valve plate 20 is more stable; on the other hand, the fitting arrangement between the valve plate 20 and the orifice plate 12 can prevent dust from entering the cavity between the valve plate 20 and the side wall portion 11 through the gap between the orifice plate 12 and the valve plate 20. If dust enters the cavity, as the dust accumulates in the cavity, it will seriously affect the movement of the valve plate 20. In addition, the dust in the cavity may overflow from the valve stem through hole set on the side wall portion 11. Therefore, the sealing between the valve plate 20 and the orifice plate 12 is very important. In order to further improve the sealing between the valve plate 20 and the orifice plate 12, grooves are provided on the surfaces of the orifice plate 12 and the valve plate 20 where relative sliding can occur to place a sealing ring. The sealing ring can improve the degree of sealing between the valve plate 20 and the orifice plate 12, and ensure that dust does not enter the cavity between the valve plate 20 and the side wall portion 11.

[0038] It should be noted that the valve plate 20 will not move to a position completely separated from the orifice plate 12, that is, the valve plate 20 always maintains surface contact with the orifice plate 12 to maintain sealing. The thickness of the orifice plate 12 is between 2 mm and 3 mm, that is, the gap between the first valve plate 21 and the second valve plate 22 is between 2 mm and 3 mm, so as to avoid wear between the first valve plate 21 and the second valve plate 22, and at the same time, dust will not enter the gap due to the gap being too large to affect the performance of the flow channel through hole 30.

[0039] Continue to refer Figure 1 and Figure 2 In the structure shown, in order to drive the valve plate 20 to move, a valve stem 40 is provided on the valve plate 20, and the valve stem 40 passes through the valve stem through hole on the valve seat and extends to the outside of the valve seat 10, and the driving mechanism is arranged on the outer wall of the valve seat 10. Since the valve stem 40 is located on the outside of the valve seat 10, it is convenient for the driving mechanism to drive the valve stem 40, so that the valve stem 40 can move along the axial direction of the valve stem through hole.

[0040] The driving mechanism includes a motor 50. In a preferred embodiment, a gear is provided at the output end of the motor 50, and the valve stem 40 is a rack matched with the gear. The gear drives the rack to move, so that the rack can move along the axial direction of the valve stem through hole. The driving mechanism is electrically connected to a controller for controlling the regulating valve, so that the controller can simultaneously issue corresponding instructions to each motor 50, so that the first valve plate 21 and the second valve plate 22 can always keep the shape of the flow channel through hole 30 as a square during the process of moving to adjust the flow channel through hole 30. In a preferred embodiment, the output end of the motor 50 and the valve stem 40 together constitute a worm gear structure, that is, a worm gear is provided at the output end of the motor 50, and the valve stem 40 is a worm, so that the torque output by the motor is converted into a reciprocating motion of the valve stem 40 along the axial direction of the valve stem through hole, and the valve stem 40 is rotatably connected to the valve plate 20 through a bearing, so that the valve plate 20 can be pushed inward or pulled outward by the valve stem 40.

[0041] The form of driving the valve plate by the driving mechanism provided in the present application is not limited to the above-mentioned structure. In another optional embodiment, the valve stem through hole is an elongated through hole opened on the valve seat 10. The driving mechanism can connect the valve stem 40 in a clamping form, and use appropriate driving parts to enable the valve plate 20 to also generate movement along the length direction of the elongated valve stem through hole, so that the valve plate 20 has more degrees of freedom.

[0042] Installed on a DN15 test pipe Figure 1 The control valve shown is used as an example of a test object, with the purpose of adjusting the pulverized coal flow rate to less than 200 kg / h. Among them, pulverized coal transportation is a typical gas-solid two-phase flow.

[0043] The opening of the regulating valve is gradually adjusted downward from 100% to 20%, and the adjustment of the powder flow rate is observed. The 100% opening state of the regulating valve means that the area of ​​the flow channel through hole 30 and the area of ​​the hole in the middle of the orifice plate 12 are completely equal. The specific method for adjusting the powder coal flow rate is as follows:

[0044] First, ensure that the opening of the regulating valve (100%, diameter cross-sectional area 0.00018m2) remains unchanged, at which time the flow rate on the coal line is 1000kg / h. Reduce the opening to 75% (diameter cross-sectional area 0.00013m2), the coal line flow rate is reduced to 800kg / h, the valve opening is reduced to 50%, the coal line flow rate is reduced to 700kg / h, the valve opening is reduced to 25%, the coal line flow rate is reduced to 250kg / h. Reduce the valve opening to 20%, and the coal line flow rate is reduced to 180kg / h.

[0045] As shown in Table 1 below, Figure 1In the regulating valve provided, from the parameters in Table 1, the regulating range of the pulverized coal flow rate can be lowered, and the change gradient of the pulverized coal flow rate brought about by the change of the valve opening is smoother. The opening of the regulating valve does not need to be reduced to less than 10%, avoiding the hidden danger of blockage caused by bridging. Figure 1 The regulating valve of the embodiment shown can effectively expand the regulating range of pulverized coal flow rate and improve the regulating accuracy of powder in gas-solid two-phase flow.

[0046] Valve Type Opening Flow cross-sectional area Pulverized coal flow V-type angle valve 50％ 9.0e-4 Blockage, flow rate unchanged One-way gate valve 30％ 5.5e-4 370kg / hr, downward blocking Figure 1 The regulating valve shown 20％ 3.5e-4 180kg / hr, meeting flow requirements

[0047] Table 1

[0048] A second aspect of the present application provides a control system for a regulating valve, the control system for the regulating valve comprising a controller and the regulating valve as described above, wherein the controller is electrically connected to the driving mechanism.

[0049] The controller can simultaneously issue corresponding instructions to each driving mechanism, reasonably adjust the movement parameters of each valve plate 20 and issue corresponding instructions, such as Figure 1 and Figure 2 For the regulating valve shown, the controller can send instructions to the motor 50 at the same time, so that the first valve plate 21 and the second valve plate 22 can always keep the shape of the flow channel through hole 30 as a square during the process of moving to adjust the flow channel through hole 30.

[0050] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications. Including the combination of various specific technical features in any suitable manner. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations. However, these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A regulating valve for conveying pulverized coal, characterized in that: The regulating valve comprises a valve seat (10), at least three valve plates (20) and a driving mechanism for driving the valve plates (20) to move, wherein the valve plates (20) are arranged in the valve seat (10) and jointly define a flow channel through hole (30), wherein at least two of the valve plates (20) are capable of moving so that the size of the flow channel through hole (30) changes in at least two non-parallel directions, thereby adjusting the area of ​​the flow channel through hole (30); The valve plate (20) comprises two first valve plates (21) arranged opposite to each other and two second valve plates (22) arranged opposite to each other, so that the flow channel through hole (30) is formed as a rectangular through hole; The two first valve plates (21) are located on a first plane and at least one of the first valve plates (21) is movable in the first plane, and the two second valve plates (22) are located on a second plane and at least one of the second valve plates (22) is movable in the second plane; The first plane and the second plane are both perpendicular to the axis of the flow channel through hole (30), and the first plane and the second plane are not coplanar; The first valve plate (21) and the second valve plate (22) move so that the flow channel through hole (30) forms a square through hole or a non-square rectangular through hole; The plate surface of the valve plate (20) facing the incoming material is an inclined surface, and the inclined surface is configured to gradually sink in a direction gradually approaching the flow channel through hole (30).

2. The regulating valve according to claim 1, characterized in that: The valve seat (10) includes a side wall portion (11) and an orifice plate portion perpendicular to the side wall portion (11), the orifice plate portion includes three orifice plates (12) parallel to each other and having through holes in the middle, the side wall portion (11) is arranged parallel to the axis of the flow channel through hole (30), the orifice plate (12) is perpendicular to the side wall portion (11), and the thickness dimension of the valve plate (20) matches the gap dimension between the two orifice plates (12) so as to be arranged between two adjacent orifice plates (12).

3. The regulating valve according to claim 2, characterized in that: The regulating valve comprises a sealing ring, a groove is formed on the surface of the orifice plate portion and / or the surface of the valve plate (20), and the sealing ring is arranged in the groove.

4. The regulating valve according to claim 1, characterized in that: The regulating valve comprises a valve stem (40) arranged on the valve plate (20); the valve seat (10) has a valve stem through hole, the valve stem (40) can pass through the valve stem (40) through hole to extend to the outside of the valve seat (10); the driving mechanism is arranged on the outer wall of the valve seat (10); the output end of the driving mechanism is connected to the valve stem (40) to drive the valve stem (40) to move.

5. The regulating valve according to claim 4, characterized in that: The driving mechanism comprises a motor (50), an output end of the motor (50) is provided with a gear, and the valve stem (40) is a rack matched with the gear so that the motor (50) can drive the rack to move.

6. A control system for a regulating valve, characterized in that: The control system of the regulating valve comprises a controller and the regulating valve according to any one of claims 1 to 5, and the controller is electrically connected to the driving mechanism.

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