Butterfly Valve

Abstract

To provide a butterfly valve, even if used in a lateral posture, causes no wear in a joint coupling a disk and an actuator and in an insertion opening in slide contact with an outer peripheral surface of the joint.SOLUTION: A butterfly valve includes: an approximately-cylindrical body 2 formed with a through flow passage 20 and a circular disc insertion opening 21 orthogonal to the flow passage 20; a body box 4 covering the body 2 and formed with an insertion opening 41 that is concentric with the disc insertion opening 21 and has an almost same diameter with the disc insertion opening; a columnar disc 3 that includes an opening / closing plate 30 for opening and closing the flow passage of the body 2 and is inserted into the insertion opening 41 and the disc insertion opening 21; a columnar joint 5 that has one end engaged with the disc 3 and the other end connected to an actuator 9; and a ring-shaped guide 6 that is disposed between the outer surface of the joint 5 and the inner surface of the insertion opening 41, in which a body-side end side 61 has a wave shape placed along a peripheral edge 22a of an opening portion of the disc insertion opening 21 of the body 2.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a butterfly valve that blocks communication of a fluid flowing through a pipe, and more particularly to a butterfly valve in which a disk serving as a valve element and a body with which the disk slides are made of ceramic. [Background technology]

[0002] A typical butterfly valve is a valve in which a disc-shaped valve element with a valve seat surface on its outer periphery is placed inside a short cylindrical valve body and configured to open and close a flow path by rotating around a valve stem (see, for example, Patent Document 1). There are also butterfly valves which consist of a cylindrical body which has a through flow path and a circular disc insertion port which is perpendicular to the flow path, and a cylindrical disc equipped with an opening / closing plate which is inserted into the disc insertion port of the body and blocks the flow of fluid, and which are configured to open and close the flow path by rotating this disc.

[0003] As shown in FIG. 6, this butterfly valve 100 has a cylindrical disk 3 cut out at a position corresponding to the body flow path, forming a plate-like opening / closing portion 30, and is configured so that the flow path can be opened and closed by rotating the disk 90°. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 62-046068 Summary of the Invention [Problem to be solved by the invention]

[0005] The butterfly valve 100 shown in FIG. 6 is used in a conveying line for granular material, for example, pulverized coal, and the disk 3 and the body 2 are generally made of ceramic. In order to treat the pulverized coal as a fluid, an introduction hole 40 for introducing a purge gas that communicates with the insertion hole 41 is opened in the body box 4 covering the body 2 in order to prevent the pulverized coal from clogging between the disk 3 and the disk insertion hole 21 opened in the body 2. A seal member S such as an O-ring is disposed between the insertion hole 41 and the pressing plate 8, and between the pressing plate 8 and the shaft of the disk 3. This allows the purge gas to flow between the disk 3 and the disk insertion hole 21 opened in the body 2, thereby preventing the pulverized coal from clogging.

[0006] The insertion opening 41 is concentric with the inner diameter of the disk insertion opening 21 and has approximately the same diameter, but the dimensions are adjusted so that the above-mentioned purging gas flows evenly between the disk insertion opening 21 and the disk 3, and so that a small annular gap is formed between the outer peripheral surface of the joint 5 to smoothly transmit the rotation of the actuator 9 to the disk 3.

[0007] For this reason, when this butterfly valve is used in a horizontal orientation in which the fluid flow is perpendicular to the horizontal direction as shown in FIG. 7, a slight gap between the body box 4 and the joint 5 causes the joint 5, which is connected to the actuator 9, which is a heavy object, to bend in the direction of the arrow Y, and the outer surface of the joint 5 and the inner surface of the insertion hole 41 of the body box 4 will wear out at the portion X.

[0008] The present invention has been made in consideration of these points, and has an object to provide a butterfly valve which, even when used in a horizontally positioned position, does not experience wear on the joint connecting the disc and actuator, or on the insertion port of the body box which comes into sliding contact with the outer peripheral surface of the joint, and which, when using purging gas, supplies purging gas evenly between the disc and the body. [Means for solving the problem]

[0009] The butterfly valve of the present invention, which has been made to solve the above problems, comprises a substantially cylindrical body forming a penetrating flow passage and a circular disc insertion port perpendicular to the flow passage, a body box covering the body and forming an insertion port concentric with and of substantially the same diameter as the disc insertion port, a cylindrical disc equipped with an opening / closing plate for opening and closing the flow passage of the body and inserted into the insertion port and the disc insertion port, a cylindrical joint having one end that engages with the disc and the other end connected to an actuator, and a ring-shaped guide disposed between the outer surface of the joint and the inner surface of the insertion port of the body box, and the body side end edge of the guide is wave-shaped and placed along the periphery of the opening of the disc insertion port of the body.

[0010] In the butterfly valve of the present invention, the body side edge of the guide is formed into a wave shape that is placed along the periphery of the opening of the disk insertion port of the body.

[0011] In this case, the guide may be formed with a notch in the axial direction, and the notch may be arranged to become the opening position of the leak port that opens into the body box.

[0012] Furthermore, in these cases the body and the disc may be made of ceramic. Effect of the Invention

[0013] According to the butterfly valve of the present invention, even if the butterfly valve is used in a horizontal position, there is no wear on the joint connecting the disc and the actuator and on the insertion port that slides against the outer peripheral surface of the joint, and it is possible to provide a butterfly valve in which, when purging gas is used, purging gas is supplied evenly between the disc and the body. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a sectional front view showing a butterfly valve according to a first embodiment of the present invention. [Diagram 2]FIG. 2 is a side view showing the butterfly valve. [Diagram 3] FIG. 2 is a partially cutaway sectional front view showing a guide portion of the butterfly valve. [Figure 4] The schematic diagram explains the arrangement of the guide and body of the butterfly valve. (a) shows the whole valve, and (b) shows an enlarged view of part A in (a). [Diagram 5] FIG. 2 is a perspective view showing a disk of the butterfly valve. [Figure 6] FIG. 1 is a sectional front view showing a conventional butterfly valve. [Figure 7] FIG. 1 is a schematic cross-sectional view illustrating wear portions of a joint and an insertion port of a conventional butterfly valve. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, preferred embodiments of the butterfly valve according to the present invention will be described with reference to the drawings. The shapes of the components and their relative positions described in the embodiments are merely illustrative examples, and are not intended to limit the scope of the present invention unless otherwise specified. In addition, for convenience, the directions of the components may be referred to as up, down, left, and right depending on the directions on the drawings, but these do not limit the scope of the present invention.

[0016] <Embodiment 1> 1 to 5 show a butterfly valve according to a first embodiment of the present invention. Fig. 1 shows a cross-sectional front view of a butterfly valve 1 of the present invention. This butterfly valve 1 includes a substantially cylindrical body 2 having a through flow passage 20 and a circular disk insertion port 21 perpendicular to the flow passage 20, a body box 4 covering the body 2 and having an insertion port 41 concentric with the disk insertion port 21 and having substantially the same diameter as the disk insertion port 21, a cylindrical disk 3 having an opening / closing plate 30 for opening and closing the flow passage of the body 2 and inserted into the insertion port 41 and the disk insertion port 21, a cylindrical joint 5 having one end engaged with the disk 3 and the other end connected to an actuator 9, and a ring-shaped guide 6 disposed between the outer surface of the joint 5 and the inner surface of the insertion port 41 of the body box 4.

[0017] [body] The material of the body 2 is not particularly limited, but in this embodiment, the fluid used is pulverized coal, and the body 2 is made of ceramics. The body 2 is cylindrical and concentric with the flow passage 20, with both ends having a smaller diameter than the body, and is sandwiched between the annular bottom of the body box 4 and the flange 7. The disk insertion opening 21 that opens perpendicularly to the flow passage 20 has a slightly larger diameter than the inner diameter of the flow passage, and the opening and closing plate 30 of the disk 3 prevents the flow of the fluid (pulverized coal) flowing through the flow passage. The disk insertion opening 21 reaches the lower side of the flow passage 20 in the figure, and receives the lower end 32 of the disk 3.

[0018] [disk] Like the body 2, the material of the disk 3 is not particularly limited, but in this embodiment, the disk 3 is made of ceramics since the fluid used is pulverized coal. The disk 3 is shaped like a cylinder that fits into the disk insertion opening 21 of the body 2, and an opening / closing plate 30 is formed by cutting out a portion between a lower end 32 and an engagement portion 31 that engages with the joint 5. A seal portion 30a that comes into sliding contact with the inner diameter portion of the disk insertion opening 21 is formed on the side of the opening / closing plate 30.

[0019] [Body Box] The body box 4 covers the body 2, and has a hole at one end that is approximately the same diameter as the trunk of the body 2 and the same dimensions as the length of the trunk, and a through hole at the other end that is smaller in diameter than the hole and approximately the same diameter as the small diameter part of the body 2. A plurality of bolt holes for fixing the flange 7 are formed at one end, and a plurality of screw holes for attaching a piping flange are formed at the other end. The flange 7 has screw holes formed at the same pitch as the screw holes, and also has insertion holes for bolts that are fastened to the bolt holes in the body box 4.

[0020] [joint] One end of the joint 5 has a groove 50 that engages with the engagement portion 31 of the disk 3, and the other end is connected to the actuator 9. The actuator side of the joint 5 has a smaller diameter than the body portion, and an annular stepped portion is formed, and the joint 5 and disk 3 are pressed toward the flow path 20 side by a pressing plate 8 fixed to the periphery of the opening end of the insertion port 41 of the body box 4 via annular packing P.

[0021] [guide] The ring-shaped guide 6 disposed between the outer surface of this joint 5 and the inner surface of the insertion opening 41 of the body box 4 has a corrugated body side end edge 61 which is placed along the periphery 22a of the opening of the disc insertion opening 21 on the outer surface 22 of the body 2, as shown in Figures 3 and 4.

[0022] The body side edge 61 of the guide 6 is corrugated to fit the periphery 22a of the opening of the disc insertion port 21 of the disc 2, so that the guide does not rotate with the rotation of the disc 3. The material and thickness of the guide 6 are not particularly limited, but according to experiments by the inventors, it is preferable that the material is polytetrafluoroethylene (PTFE) and the thickness is about 1 mm, and it was found that if a corrugated shape is not adopted, the guide will get caught in the sliding portion, causing malfunction.

[0023] This guide 6 is made by cutting or punching a plate-shaped PTFE and then winding it. When winding and configuring it to fit the inner peripheral surface of the insertion opening 41, a certain gap is provided between the mating edges to form a notch 60. Then, when attaching to the insertion opening 41, this notch 60 is arranged to be located at the opening of the inlet 40 through which the purge gas is introduced. This allows the introduced purge gas to be easily and uniformly blown between the disk insertion opening 21 of the body 2 and the disk 3, and pulverized coal that enters the gap between the disk insertion opening 21 and the disk 3 can be returned to the flow path 20. [Industrial Applicability]

[0024] The butterfly valve of the present invention, even if used in a horizontally positioned configuration, does not experience wear on the joint connecting the disk and the actuator or on the insertion port that slides against the outer peripheral surface of the joint, and therefore can be suitably used as a horizontally positioned butterfly valve, as well as a butterfly valve for a line that transports pulverized coal and requires the spraying of purging gas. [Explanation of symbols]

[0025] 1. Butterfly valve 2. Body 20 Flow Path 21 External surface 22 Disk slot 3 Disc 30 Shielding plate 4. Body Box 40 Introduction hole 41 Insertion port 5 Joint 6 Guide 60 Notch 61 Curved Edge 7 Flange 8 Presser plate 9 Actuators

Claims

1. a substantially cylindrical body having a through-flow passage and a circular disk insertion opening perpendicular to the through-flow passage; a body box covering the body and having an insertion opening concentric with and having approximately the same diameter as the disk insertion opening; a cylindrical disk including an opening / closing plate for opening and closing a flow path of the body and inserted into the insertion opening and the disk insertion opening; a cylindrical joint having one end that engages with the disk and another end that is connected to an actuator; a ring-shaped guide disposed between an outer surface of the joint and an inner surface of the insertion hole, The body side edge of the guide is wave-shaped and placed along the periphery of the opening of the disk insertion port of the body.

2. 2. The butterfly valve according to claim 1, wherein the guide is formed with a notch in the axial direction, the notch being arranged to correspond to an opening position of a leak port opening into the body box.

3. 3. A butterfly valve as claimed in claim 1 or 2, wherein the body and the disc are made of ceramic.

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