Low-torque butterfly valve

Abstract

The utility model belongs to the technical field of valves, and particularly discloses a low-torque butterfly valve which comprises a valve body, a butterfly plate, a pressing plate, a fastener and a sealing ring, the butterfly plate and the pressing plate are locked and fixed through the fastener, the butterfly plate is rotationally connected with the valve body, and after the butterfly plate and the pressing plate are locked and fixed through the fastener, the sealing ring is arranged on the pressing plate. The butterfly plate and the pressing plate are attached to form an annular clamping cavity, the fixed end of the sealing ring is attached to the inner wall of the clamping cavity in a sealed mode, the sealing end of the sealing ring protrudes out of the clamping cavity and is used for being matched with a valve seat of the valve body to form a sealing pair, and meanwhile a compression space is reserved between the side face of the sealing end and the inner wall of the clamping cavity. The butterfly valve has the advantage of being small in opening torque.

Description

Technical Field

[0001] This application belongs to the technical field of valves, and more specifically, relates to a low-torque butterfly valve. Background Art

[0002] A butterfly valve is a pipeline accessory commonly used in pipelines to open and close pipelines and regulate and control the flow rate of the conveyed medium.

[0003] In the related art, as disclosed in a Chinese patent document with a publication number of CN221278489U, a butterfly valve includes a valve body and a butterfly plate. Among them, the butterfly plate is rotatably arranged inside the valve body, a pressing plate is fixedly connected to the butterfly plate by bolts, and a sealing ring is arranged between the butterfly plate and the pressing plate.

[0004] For such a butterfly valve, when adjusting the bolts to make the butterfly plate and the pressing plate squeeze and lock the sealing ring, a reserved gap is usually formed between the butterfly plate and the pressing plate. So that when the butterfly valve is in the closed state, the medium can enter the gap to form an outward extrusion force on the sealing ring, and the deformation of the sealing ring is used to ensure the sealing stability of the butterfly valve. However, in practice, since the gap is difficult to control very precisely, when adjusting the bolts, it is easy to cause the sealing ring to be locked and deformed too much, so that the sealing end of the sealing ring will protrude too much beyond the outer edge of the butterfly valve, and then the friction force between the sealing pairs that must be overcome during the opening and closing process of the butterfly valve is greatly increased, increasing the opening torque of the butterfly valve. Summary of the Utility Model

[0005] Aiming at the defects or improvement requirements of the prior art, this application provides a low-torque butterfly valve, aiming to improve the problem that the sealing ring is prone to increase the opening torque due to excessive locking deformation.

[0006] A low-torque butterfly valve provided by this application specifically includes a valve body, a butterfly plate, a pressing plate, a fastener and a sealing ring. The butterfly plate and the pressing plate are locked and fixed by the fastener, and the butterfly plate is rotatably connected to the valve body, wherein:

[0007] After the butterfly plate and the pressing plate are locked and fixed by the fastener, the butterfly plate and the pressing plate are in contact and form an annular clamping cavity, and the fixed end of the sealing ring is hermetically attached to the inner wall of the clamping cavity. The sealing end of the sealing ring protrudes from the clamping cavity and is used to cooperate with the valve seat of the valve body to form a sealing pair. At the same time, a compression space is left between the side surface of the sealing end and the inner wall of the clamping cavity.

[0008] Through the above technical solution conceived by this application, compared with the prior art, when assembling this butterfly valve, the fastener can be directly locked, so that the compression amount of the sealing ring can be directly controlled at a certain amount to eliminate the human factors during assembly. This design reduces the technical requirements for assembly workers in the assembly process of the butterfly valve, improves production efficiency, and makes it unnecessary to adjust the tightness of the locking part to adjust the compression amount of the sealing ring during the assembly process, avoiding the common problems in the traditional design: it is difficult to accurately control the tightness of the bolt, and in practice, the bolt is likely to be adjusted too tightly, resulting in too large deformation of the locked sealing ring, and further increasing the opening torque of the valve.

[0009] In addition, due to the existence of the compression space, when the medium flows forward along the inner flow path of the valve body, the medium can squeeze the sealing ring through the compression space between the sealing end of the butterfly plate and the sealing ring, so that the valve reaches the sealing specific pressure and realizes reliable sealing; when opening and closing the valve, the compression spaces on both sides can also provide the deformation amount for the sealing ring, thereby reducing the torque and preventing the sealing ring from being over-squeezed and damaged.

[0010] As a further preference, clamping grooves for forming the clamping cavity are arranged on the sides of the butterfly plate and the pressing plate.

[0011] As a further preference, the thickness of the fixed end of the sealing ring is greater than that of the sealing end, and the clamping groove includes an inner ring groove, and the inner ring groove is fitted with the fixed end of the sealing ring.

[0012] As a further preference, the clamping groove includes an outer ring groove, and the outer ring groove is located at the outer peripheral edge of the butterfly plate and the pressing plate for forming the compression space.

[0013] As a further preference, the outer wall of the valve body is recessed from the outside to the inside and the inner wall bulges inward to form a valve seat.

[0014] As a further preference, the valve body is an integrally cast part.

[0015] As a further preference, the valve seat has a flow-facing surface, a sealing surface and a back-flow surface, and the flow-facing surface, the sealing surface and the back-flow surface are smoothly connected in sequence along the direction of the medium inlet and outlet to form a streamlined curved surface.

[0016] As a further preference, the flow-facing surface and the back-flow surface are symmetrically arranged on both sides of the sealing surface.

[0017] As a further preference, a wear-resistant layer is arranged at the vertex part of the sealing surface of the valve seat.

[0018] As a further preference, this butterfly valve further includes a valve shaft and a bottom end cover, wherein:

[0019] The valve shaft is rotatably assembled in the valve body along the journal of the valve body, and the valve shaft is connected with the butterfly plate;

[0020] The bottom end cover is assembled on the outer end face of the journal, and the bottom end cover contacts the valve shaft;

[0021] A groove is provided at the contact surface of the valve shaft and / or the bottom end cover.

[0022] Generally speaking, compared with the prior art, the above technical solutions conceived by this application mainly have the following technical advantages:

[0023] 1. When assembling this butterfly valve, the fastener can be directly locked, so that the compression amount of the sealing ring can be directly controlled at a certain amount, eliminating the human factor during assembly, and effectively controlling the extrusion amount of the sealing ring; and due to the existence of the compression space, when the medium flows forward in the valve body, the medium can squeeze the sealing ring through the compression space between the butterfly plate and the sealing ring, so that the valve reaches the sealing specific pressure and realizes reliable sealing; when opening and closing the valve, the compression spaces on both sides can also provide deformation amount for the sealing ring, thereby reducing the torque and preventing the sealing ring from being damaged due to excessive extrusion.

[0024] 2. Through the symmetric streamline convex design of the valve seat of the valve body, when the butterfly valve is opened, it basically only needs to overcome the effective interference amount of the sealing ring, and the opening torque of the butterfly valve is small.

[0025] 3. Since a groove is provided at the contact surface of the valve shaft and the bottom end cover, the contact area between the bottom end cover and the lower end face of the valve shaft is reduced, the friction between the bottom end cover and the valve shaft is reduced, and thus the opening torque of the butterfly valve is reduced. Description of the Drawings

[0026] Figure 1 is a cross-sectional view of a low-torque butterfly valve provided by an embodiment of the present application;

[0027] Figure 2 is Figure 1 an enlarged view of part A in

[0028] Figure 3 is a partial cross-sectional view of the butterfly plate and the pressing plate provided by an embodiment of the present application;

[0029] Figure 4 is a partial cross-sectional view of the valve body provided by an embodiment of the present application.

[0030] In all the drawings, the same reference numerals are used to represent the same elements or structures, where:

[0031] 1. Valve body; 1-1. Valve seat; 1-2. Journal; 1-A. Flow-facing surface; 1-B. Wear-resistant layer; 1-C. Flow-back surface; 2. Butterfly plate; 3. Pressure plate; 4. Fastener; 5. Sealing ring; 5-1. Fixed end; 5-2. Sealing end; 6. Clamping groove; 6-1. Inner ring groove; 6-2. Outer ring groove; 7. Valve shaft; 8. Actuator; 9. Bottom end cover; 10. Compression space; 20. Groove. Detailed implementation manners

[0032] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0033] The following will further describe the present application in detail with reference to the attached Figures 1-4 The present application will be further described in detail.

[0034] The embodiment of the present application discloses a low-torque butterfly valve. Referring to Figures 1-2 , the low-torque butterfly valve includes a valve body 1, a butterfly plate 2, a pressure plate 3, a fastener 4 and a sealing ring 5. The butterfly plate 2 is rotatably arranged in the valve body 1, and the butterfly plate 2 and the pressure plate 3 are locked and fixed by the fastener 4. Among them, after the butterfly plate 2 and the pressure plate 3 are locked and fixed by the fastener 4, the butterfly plate 2 and the pressure plate 3 are in contact with each other and form an annular clamping cavity. The fixed end 5-1 of the sealing ring 5 is in sealing fit with the inner wall of the clamping cavity, and the sealing end 5-2 of the sealing ring 5 protrudes from the clamping cavity and is used to cooperate with the valve seat 1-1 of the valve body 1 to form a sealing pair. At the same time, a compression space 10 is left between the side surface of the sealing end 5-2 and the inner wall of the clamping cavity.

[0035] It should be noted that the fastener 4 includes but is not limited to structures such as bolts and screws. In this embodiment, the fastener 4 is preferably a screw.

[0036] Furthermore, as Figures 2-3 shown, in this embodiment, clamping grooves 6 are provided on the side surfaces (i.e., the facing surfaces) of the butterfly valve and the pressure plate 3. After the butterfly plate 2 and the pressure plate 3 are locked and fixed by the fastener 4, the clamping grooves 6 between the butterfly plate 2 and the pressure plate 3 cooperate with each other to form a clamping cavity.

[0037] Certainly, in some other embodiments, the clamping groove 6 may also be provided at the edge of the facing surfaces of the butterfly plate 2 and the pressure plate 3. After the butterfly plate 2 and the pressure plate 3 are locked and fixed, the clamping groove 6 can also form a clamping cavity.

[0038] Further, the thickness of the fixed end 5-1 of the sealing ring 5 is greater than that of the sealing end 5-2. Correspondingly, at least one clamping groove 6 includes an inner ring groove 6-1, and the inner ring groove 6-1 is fitted with the fixed end 5-1 of the sealing ring 5, so that the fixed end 5-1 of the sealing ring 5 is anti-detachingly installed in the clamping cavity, and a relatively large sealing contact area is formed between the fixed end 5-1 of the sealing ring 5 and the inner wall of the clamping cavity.

[0039] Preferably, in this embodiment, the cross-section of the sealing ring 5 is generally in an inverted "T" shape; in other embodiments, a sealing ring 5 with an "L" shaped cross-section or other cross-sectional forms can also be selected, as long as the fixed end 5-1 of the sealing ring 5 can stably and sealingly contact the butterfly plate 2 and the pressing plate 3.

[0040] Further, in this embodiment, to form the compression space 10, the clamping groove 6 further includes an outer ring groove 6-2, and the outer ring groove 6-2 is located at the outer peripheral edge of the butterfly plate 2 and the pressing plate 3. As Figure 2 shown, after the butterfly plate 2 and the pressing plate 3 are locked and fixed by the fastener 4, a gap is left between the side surface of the sealing end 5-2 and the inner wall of the outer ring groove 6-2 to form the above-mentioned compression space 10.

[0041] Under this design, when assembling this butterfly valve, the fastener 4 can be directly locked, so that the compression amount of the sealing ring 5 can be directly controlled at a certain value, thereby eliminating the human factor during assembly. This design reduces the technical requirements for assembly personnel during the assembly process of the butterfly valve, improves production efficiency, and makes it unnecessary to adjust the tightness of the locking part to adjust the compression amount of the sealing ring 5 during the assembly process. It also avoids the common problems in traditional designs: it is difficult to accurately control the tightness of the bolt, and in practice, the bolt is likely to be adjusted too tightly, resulting in too much deformation of the locked sealing ring 5, and further increasing the opening torque of the butterfly valve.

[0042] In addition, since a certain compression space 10 is given to the sealing ring 5 at the pressing plate 3 and the butterfly plate 2, when the medium flows through the inner flow path of the valve body 1, for example, when the medium flows in the forward direction (i.e., along the Figure 1 direction of the arrow a shown), the sealing ring 5 can be squeezed through the gap between the butterfly plate 2 and the sealing end 5-2 of the sealing ring 5, so that the butterfly valve reaches the sealing specific pressure and realizes reliable sealing; when opening and closing the valve, the compression spaces on both sides can provide a deformation amount for the sealing ring, thereby reducing the torque and preventing the sealing ring from being over-squeezed and damaged.

[0043] Further, as Figure 2 、 4 shown, in this embodiment, the outer wall of the valve body 1 is recessed from the outside to the inside and the inner wall is protruded inward to form a valve seat 1-1, and the valve body 1 is preferably an integrally cast part. Under this design, the obtained valve body 1 has a high quality and is not prone to casting defects.

[0044] Of course, in other embodiments, the valve body 1 adopted may also be a valve body 1 in other manufacturing forms in the prior art, and the valve seat 1-1 in the valve body 1 may also be a valve seat 1-1 in such ways as splicing, welding, screw assembly, etc.

[0045] Furthermore, in some embodiments, the valve seat 1-1 has a flow-facing surface 1-A, a sealing surface, and a backflow surface 1-C. The flow-facing surface 1-A, the sealing surface, and the backflow surface 1-C are smoothly connected in sequence along the direction of medium inlet and outlet to form a streamlined curved surface. Further preferably, the flow-facing surface 1-A and the backflow surface 1-C are symmetrically arranged on both sides of the sealing surface.

[0046] Under this design, the valve seat 1-1 of the valve body 1 presents a "hillside type", and the slopes on both sides are in a smooth transition state, so that the butterfly valve basically only needs to overcome the effective interference amount of the sealing ring 5 during the opening process. Compared with traditional butterfly valves with single-bevel or stepped valve seats, the torque of this butterfly valve is smaller and the fluid flow capacity is better. In addition, in this design, since the shapes of both sides of the streamlined curved surface of the valve seat 1-1 are symmetrical, the concave shapes of the inner and outer surfaces of the valve body 1 are also symmetrical, which makes it easy for the valve body 1 to be cast and processed to form a state with uniform wall thickness.

[0047] Furthermore, as Figure 4 shown, in some embodiments, a wear-resistant layer 1-B is also provided at the vertex part of the sealing surface of the valve body 1. The surface of the wear-resistant layer 1-B is streamlined, and the wear-resistant layer 1-B is preferably formed by surfacing stainless steel.

[0048] Furthermore, as Figure 1 shown, the butterfly valve adopts a valve shaft 7 assembled in the valve body 1, that is: the valve shaft 7 is connected to the butterfly plate 2, and the valve shaft 7 is rotatably assembled in the valve body 1 along the journal 1-2 of the valve body 1. On this basis, an actuator 8 can also be assembled on the outer end surface of the top journal 1-2 of the butterfly valve. The actuator 8 is used to drive the valve shaft 7 to rotate so as to drive the butterfly plate 2 to perform the opening and closing adjustment of the butterfly valve. The actuator 8 is prior art and will not be elaborated here.

[0049] Furthermore, in some embodiments, a bottom end cover 9 is assembled on the outer end surface of the bottom journal 1-2 of the butterfly valve, and the end surface of the bottom valve shaft 7 in the valve body 1 contacts the bottom end cover 9. In this butterfly valve, a groove 20 can be opened at the contact surface of the valve shaft 7 and / or the bottom end cover 9. By setting the groove 20, the contact area between the valve shaft 7 and the bottom end cover 9 can be reduced, thereby reducing the friction force between the bottom end cover 9 and the valve shaft 7 and reducing the opening torque of the butterfly valve. As a preference, the groove 20 is opened at the contact surface of the bottom end cover 9.

[0050] It should be understood that expressions such as "including" and "may include" used in this application indicate the existence of disclosed functions, operations, or components, and do not limit the existence of one or more additional functions, operations, and components. In this application, terms such as "including" and / or "having" may be interpreted as indicating a specific characteristic, number, operation, component, component, or a combination thereof, but do not exclude the existence or possibility of addition of one or more other characteristics, numbers, operations, components, components, or a combination thereof.

[0051] It should be understood that the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to this application.

[0052] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality of" means two or more, unless otherwise specifically defined.

[0053] In this application, unless otherwise clearly specified and limited, terms such as "install", "connect", "connection", "fix", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0054] It is easy for those skilled in the art to understand that the above are only preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of this application shall be included in the protection scope of this application.

Claims

1. A low-torque butterfly valve, characterized in that, It includes a valve body (1), a butterfly plate (2), a pressing plate (3), fasteners (4) and a sealing ring (5). The butterfly plate (2) and the pressing plate (3) are locked and fixed by the fasteners (4). The butterfly plate (2) is rotatably connected to the valve body (1). Among them: After the butterfly plate (2) and the pressing plate (3) are locked and fixed by the fasteners (4), the butterfly plate (2) and the pressing plate (3) are in contact and form an annular clamping cavity. The fixed end (5-1) of the sealing ring (5) is hermetically fitted with the inner wall of the clamping cavity. The sealing end (5-2) of the sealing ring (5) protrudes from the clamping cavity and is used to cooperate with the valve seat (1-1) of the valve body (1) to form a sealing pair. At the same time, a compression space (10) is left between the side surface of the sealing end (5-2) and the inner wall of the clamping cavity.

2. The low-torque butterfly valve according to claim 1, wherein Clamping grooves (6) for forming the clamping cavity are provided on the side surfaces of the butterfly plate (2) and the pressing plate (3).

3. The low-torque butterfly valve according to claim 2, wherein The thickness of the fixed end (5-1) of the sealing ring (5) is greater than the thickness of the sealing end (5-2). The clamping groove (6) includes an inner ring groove (6-1), and the inner ring groove (6-1) is fitted with the fixed end (5-1) of the sealing ring (5).

4. The low-torque butterfly valve according to claim 2, wherein The clamping groove (6) includes an outer ring groove (6-2). The outer ring groove (6-2) is located at the outer peripheral edge of the butterfly plate (2) and the pressing plate (3) and is used to form the compression space (10).

5. The low-torque butterfly valve according to any one of claims 1-4, characterized in that The outer wall of the valve body (1) is recessed from the outside to the inside and the inner wall bulges inward to form a valve seat (1-1).

6. The low-torque butterfly valve according to claim 5, characterized in that, The valve body (1) is an integrally cast part.

7. The low-torque butterfly valve according to claim 5, wherein The valve seat (1-1) has a flow-facing surface (1-A), a sealing surface and a flow-back surface (1-C). The flow-facing surface (1-A), the sealing surface and the flow-back surface (1-C) are smoothly connected in sequence along the direction of medium inlet and outlet to form a streamlined curved surface.

8. The low-torque butterfly valve according to claim 7, wherein The flow-facing surface (1-A) and the flow-back surface (1-C) are symmetrically arranged on both sides of the sealing surface.

9. The low-torque butterfly valve according to claim 7, wherein A wear-resistant layer (1-B) is provided at the vertex of the sealing surface of the valve seat (1-1).

10. The low-torque butterfly valve according to any one of claims 1-4, characterized in that, This butterfly valve further includes a valve shaft (7) and a bottom end cover (9). Among them: The valve shaft (7) is rotatably assembled in the valve body (1) along the journal (1-2) of the valve body (1), and the valve shaft (7) is connected to the butterfly plate (2). The bottom end cover (9) is assembled on the outer end face of the journal (1-2), and the bottom end cover (9) is in contact with the valve shaft (7). Grooves (20) are provided at the contact surfaces of the valve shaft (7) and / or the bottom end cover (9).

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