JPH0434028B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is a butterfly valve that opens and closes the valve by rotating the valve body by 90 degrees, and is installed in the middle of a pipe to open and close the flow of fluid. It is used for control including control, and particularly relates to small butterfly valves.

(Prior art) Butterfly valves have traditionally been suitable for diameters of 2 inches or more (1 1/2 inches are also available from foreign manufacturers); It is more advantageous than type valves, gate valves, etc., and has been widely used in recent years. This is also because complete sealing has become possible, especially by using an elastic body such as synthetic rubber in the sealing portion.

On the other hand, small-sized rosefly valves have traditionally been available in general-purpose globe valves, gate valves, ball valves, cockpit valves, and the like, so there has been no tendency to expand into the small-diameter field. However, in various plants, there are many requests for valves that can be opened and closed by rotating 90 degrees, similar to butterfly valves, and a variety of studies have been conducted for this purpose.

On the other hand, as shown in Figure 7, butterfly valves are often flangeless (wafer type) in which the valve body does not have a flange, and when piping, the valve body is placed between the flanges provided on the pipe. The method of inserting and tightening from both sides was often used.

(Problems to be Solved by the Invention) As mentioned above, large diameter butterfly valves are often used, and these large diameter valves are difficult to insert between flanges when assembled in a piping system. There were many flangeless methods in which the bolts were tightened and then tightened from both sides, but especially in the case of small butterfly valves,
If such a flange connection is used in the middle of a pipeline, the plant equipment itself becomes large, making it unsuitable.

In addition, butterfly valves have the disadvantage that even when the valve body is fully opened, the valve body remains inside the valve body, so there is a fluid loss (pressure loss) when the valve is opened, and this is especially noticeable for small diameter ones. Ta.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a butterfly valve in which there is no pressure loss in the flow path in the valve chamber when the valve is fully opened, and the valve body can be made smaller.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides that inflow and outflow pipes are screwed into the openings connected to the valve ports located on both sides of the valve chamber. A valve body is provided in the valve chamber with a side face made of a part of a cylinder for opening and closing the valve port, and is formed by hollowing out the center of the circular body, and is rotated by a valve shaft. In a movably inserted butterfly valve, the valve chamber formed inside the valve body is formed into a cylindrical shape centered on the valve shaft, and the central portion of the circular valve body inserted into the cylindrical valve chamber is is formed by hollowing out the side surface portion and the upper and lower circular portions so that the longitudinal section in the axial direction forms a U-shape, and lining the outer peripheral surface of the side surface portion of the valve body is made of an elastic material, The valve is fully opened or fully closed by rotating the valve body by 90 degrees, and when fully opened, the lining of the side surface of the valve body is inserted into the inside of the valve chamber located between the valve ports on both sides. A valve seat portion on which a side surface portion of the valve body made of a part of the cylinder is seated when the valve body is fully closed is provided in a raised manner around a rectangular valve opening of the valve body, and the valve seat portion It is characterized by having a slope on the periphery.

(Function) Since the present invention is configured as described above,
The inflow and outflow piping is connected by screwing into both threaded openings in the valve body. Note that during this connection, they are sealed with Teflon (trade name) tape or bond.

In the fully open state shown in FIG. 1A, the side surface of the valve body, which is a part of the cylinder, is housed on the outside of the surface connecting the edges of both valve ports of the valve body, and is in the flow path inside the valve chamber. Since there is nothing blocked by the valve body, the fluid loss (pressure loss) when the valve is opened is extremely small.

Next, by rotating the valve shaft by 90 degrees, the side surface of the valve body, which is a part of the cylinder, is moved from the storage position in the valve body to the cylindrical inner surface in the valve chamber.
It is displaced 90 degrees and rotated to the fully closed position, which closes the valve port shown in Figure 4A. At this time, the elastic lining material applied to the outer peripheral surface of the side surface of the valve body, which is a part of the cylinder, is seated on the valve seat formed around the valve port, so that the valve port is sealed. The fully closed state is maintained.

In addition, when opening the valve from the closed state, the valve shaft may be rotated by 90° in the opposite direction.

Note that when the pipe is connected to the valve body, the fluid flow direction is one-way (No. 4A) rather than the closed state of the valve body.
(Left → right in the figure) is preferable. In addition, the rotation direction of the valve body is indicated by the upper handle, and the stopper
It is designed to be able to rotate 90°.

(Example) Next, embodiments of the present invention will be described with reference to the drawings.

Figure 1A is a cross-sectional view taken along the - line in Figure 2 of a small butterfly valve showing an embodiment of the present invention in the direction perpendicular to the valve axis, Figure 1B is a side view of Figure 1A, and Figure 2 is Figure 1A. FIG. In the figure, the openings at both ends of the valve box 1 include
Threads 1a, 1a are cut for connection with the inflow and outflow pipes, respectively, and the inside of the valve chamber 1c, which has a cylindrical inner surface, has a vertical cross section in the valve axis direction, as shown in FIG. A side part 2a consisting of a part of a cylinder and upper and lower circular parts 2b, 2b so as to form a shape of
A valve body 2 is formed by hollowing out the central part 2c of a circular body, leaving the central part 2c, and is rotatably inserted into the valve shaft 3.
As shown in FIG. 4A, a lining material 11 made of an elastic body is stretched around the circumferential surface of the tube.

Further, both ends of the valve shaft 3 extend upward through the center of the lid 4 through a gland packing 5 and a dust seal 6, and are connected to a handle 9 for rotation by 90 degrees, while adjusting the vertical movement by thrust receivers 8 and 7. has been done. The valve body 1 and the lid 4 constitute a valve body. In the figure, 10 indicates a sealing material.

On the other hand, as shown in FIG. 4B, around the valve port 1b of the valve body 1, when the valve port is closed, the valve body side portion 2a is
A slightly raised valve seat part 15 on which an elastic lining material 11 is seated is formed in an annular shape, and both sides of the raised valve seat part 15 are in contact with the valve body side parts 2a. At the time, elastic lining material 11
The slopes 15a, 15a are provided so as not to damage the valve body 2, thereby allowing the valve body 2 to rotate freely.

Note that the above-mentioned contact surface between the valve body side part 2a and the valve seat 15 should actually be lined with an elastic body only in the area in contact with the valve seat part 15, but as mentioned above, it is necessary to line the contact surface with an elastic body due to rotation. Fully lined to prevent peeling and damage.

FIG. 5A is a plan view of the valve port 1b of the valve box, which valve port has a rectangular shape with a width A and a height B;
Its width A and height B correspond to A and B shown in FIGS. 1A and 2, respectively. Also 5th B
The figure is a plan view of the elastic lining member 11 stretched over the cylindrical circumferential surface of the valve body side portion 2a. As mentioned above, since the valve opening is rectangular, 100% of the fluid passage cross-sectional area of the valve body can be secured. Therefore, the rectangular cross section of the valve body is opened and closed by a valve body having a U-shaped vertical cross section.

Next, to explain the action, when the valve is fully open,
As shown in FIG. 1A, the inner plane part 2d of the valve body side part 2a is housed in a position that coincides with the plane connecting the edges of both valve ports 1b, 1b, so that it is stored in the valve chamber 1c. There is nothing blocking the rectangular valve ports 1b, 1b, and therefore fluid loss (pressure loss) when the valves are opened can be extremely small.

Also, use the handle 9 to move the valve stem 3 in the direction indicated by the handle until it hits the stopper.
By rotating 90 degrees, the valve body side part 2a, which is a part of a cylinder, moves from the storage position shown in FIG. 1A.
It is displaced by 90 degrees along the cylindrical inner surface of the valve chamber 1c and rotated to the closed position of the valve port 1b shown in FIG. 4A. At this time, the lining layer 11 stretched around the circumferential surface of the valve body side portion 2a is seated on the valve seat 15 formed around the valve port, so the valve port is sealed.
The fully closed state is maintained. In addition, when opening from the closed state, the valve shaft may be rotated 90 degrees in the opposite direction to the above.

According to this example, in ordinary valves, the material of the valve seat and valve body is often a metal-metal combination, and it is common practice to polish them together by rubbing them together in order to achieve a complete seal. Therefore, the shape of the valve body is a conical shape with a slight slope, and the valve body is pressed strongly from above and tightened to close it, whereas in this example, one side is made of an elastic body. Therefore, it is no longer necessary to match the actual parts and tighten them strongly as in the conventional method.

Furthermore, since fluid loss during circulation is extremely small, it is particularly effective for small butterfly valves.

(Effects of the Invention) As explained above, according to the present invention, the following effects are achieved.

() By combining a valve body with a U-shaped longitudinal section in the axial direction and a rectangular valve port, there is no obstruction in the flow path within the valve chamber when the valve is fully open. Therefore, the pressure loss of the fluid can be extremely small, and by making the rectangular valve port vertically long, the valve body can be made smaller.

() An elastic lining is provided on the side surface of the valve body, and when the valve is fully opened, the elastic lining is kept in a narrow position inside the valve chamber located between the valve ports on both sides. The elastic lining part is not exposed to the flow part when the valve is open, so there is no risk of it peeling off or being damaged by the flow velocity, and when the valve body is fully closed, the elastic lining part of the valve body is not exposed to the flow area around the rectangular valve opening of the valve body. Since it is seated on the raised valve seat, the valve port is sealed, making it possible to achieve a complete seal with greater sealing performance than conventional metal-to-metal systems.

() Not only can the sealing performance be further improved depending on the flow direction, but also the spherical valve body of the conventional conical Kotoku and ball valves.
Since a valve body with a U-shaped cross section is used, manufacturing is easy without the need for special machine tools.

[Brief explanation of drawings]

FIG. 1A is a cross-sectional view of a small butterfly valve showing an embodiment of the present invention in the direction perpendicular to the valve axis taken along the line in FIG. 2, FIG. 1B is a side view of FIG. 1A, and FIG. 3 is a perspective view of the valve body, 4A and 4B are enlarged explanatory views of the valve body and the seating portion of the valve body, and 5A and 5B are the valve body. FIG. 6 is a side view of the entire butterfly valve showing the state in which it is piped, and FIG. 7 is a perspective view of the conventional butterfly valve. 1...Valve box, 1a...Threaded part, 1b...Valve port,
1c... Valve chamber, 2... Valve body, 2a... Valve body side part, 2b... Thin circular part, 3... Valve stem, 11...
Lining member, 15...Valve seat portion, 15a...Slope.

Claims (1)

[Claims] 1. Threaded parts for screwing inflow and outflow pipes are formed in the openings connected to the valve ports located on both sides of the valve chamber, and a cylindrical part for opening and closing the valve port is formed in the valve chamber. In a butterfly valve, a valve body formed by hollowing out the center part of a circular body and having a side part consisting of a circular body is rotatably inserted by a valve shaft, and the valve chamber formed inside the valve body is connected to the valve shaft. The central part of the circular valve body to be inserted into the cylindrical valve chamber is formed into a cylindrical shape with the center at the cylindrical valve chamber. A lining made of an elastic material is applied to the outer peripheral surface of the side surface of the valve body, and the valve is fully opened or closed by rotating the valve body by 90 degrees, When fully opened, the lining part of the side surface of the valve body is kept in a narrow position inside the valve chamber located between the valve ports on both sides, and when fully closed,
A valve seat portion on which a side surface portion of the valve body made of a part of the cylinder is seated is provided in a raised manner around a rectangular valve port of the valve body, and a peripheral edge of the valve seat portion is provided with a slope. A small butterfly valve.