JPH041428Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is a butterfly valve, in particular, which aims to reduce cavitation and noise, whose shape can be easily changed depending on the usage conditions, and which doubles as a wear-resistant seat. This article relates to a butterfly valve that can be used for many years.

[Background of the idea]

Generally, in a butterfly valve that is pivoted and rotates, the back side of the valve body on the downstream side is under negative pressure and bubbles are generated from the outer periphery of the valve body.
It collides with the inner wall of the pipe to which the valve body is attached and collapses, causing cavitation, causing noise and vibration, and eroding the valve body and pipe line.

In order to solve this problem, a valve body in which a rectifying plate or a wing-shaped plate for reducing negative pressure has been attached to the valve body has recently been developed, but in the case of this conventional butterfly valve, the rectifying plate Since the butterfly valve and wing-shaped plate are integrally provided with the valve body, it is not possible to adapt to different usage conditions, and a butterfly valve must be manufactured separately for each condition.

[Purpose of invention]

Therefore, the present invention was devised by focusing on the problems of the above-mentioned conventional technology. To provide a butterfly valve which uses a strong material such as stainless steel for the sole and also serves as a seat, can withstand long-term use, and is economically advantageous.

[Means for trying to solve problems]

In order to achieve this objective, the butterfly valve according to the present invention has an auxiliary plate formed of a highly wear-resistant material in the shape of a broken circle in a notch provided on the outer periphery of the valve body. It is fixed to the front and rear surfaces, and one auxiliary plate has a plurality of rectifying vanes arranged in parallel, and the other auxiliary plate has a rectifying vane that reduces negative pressure.

[Effect]

By configuring the butterfly valve as described above, the auxiliary plate serves as the rectifying vane plate or the rectifying vane plate and seat, so it is possible to mount a pre-prepared auxiliary plate regardless of the type of butterfly valve. Furthermore, since the mounting distance can be adjusted, it is possible to easily obtain a desired butterfly valve that corresponds to the conditions of use, and it can withstand use for many years.

〔Example〕

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

The drawings show an embodiment of the present invention, and in the drawings 1
indicates the axis. A valve body 2 is attached to the shaft 1 in a coaxial manner in the axial direction thereof, and the valve body 2 rotates as the shaft 1 rotates to open and close the pipeline.

In addition, a step-shaped missing portion 3 is provided on the outer peripheral end surface of the valve body 2.
In the missing portion 3, auxiliary plates 5a and 5b in the shape of a missing circle are provided with screws 6, 5a and 5b on the opposing front and rear surfaces of the valve body 2, also at positions along the rotational direction of the valve body 2. 6... is detachably attached. Further, the auxiliary plate 5a described above is arranged on the upstream side (primary side), and on the outer surface of the auxiliary plate 5a, rectifying vanes 7, 7, . . . are arranged in parallel at predetermined intervals. On the other hand, the auxiliary plate 5b is arranged on the downstream side (secondary side), and the outer surface of the auxiliary plate 5b has support walls 8, 8, . . . having tapered top surfaces.
are arranged in parallel at a predetermined interval, and the supporting walls 8, 8
A rectifying vane plate 9 is formed on the front end surface of.... This rectifier vane 9 may be flat as shown in FIG. 5, or arc-shaped as shown in FIG.
It may be formed into Further, the auxiliary plates 5a and 5b form engagement step portions corresponding to the missing portions 3 of the valve body 2, so that the fitting is tightly secured.

As described above, the auxiliary plates 5a, 5b of the valve body 2 are also used as the rectifying vanes 7, 7... and the rectifying vanes 9, 9.
By forming the butterfly valve with a strong material such as stainless steel that also serves as the seat, it can be applied regardless of the form of the butterfly valve itself, such as axial type, eccentric type, concentric type, etc. Also, when attaching the auxiliary plates 5a and 5b to the valve body 2,
The distance dimension can be adjusted. That is, the fluid flowing in the pipe 10 is dispersed in a fluid state on the upstream and downstream sides, causing the flow on the passage surface to become biased and destroying the negative pressure area, resulting in cavitation occurring on the back surface of the valve body 2. This is expected to reduce the amount of noise and vibration that comes with it.

[Effect of idea]

As mentioned above, according to the butterfly valve according to the present invention, the rectifying blade plate and the rectifying vane plate are used as an auxiliary plate that also serves as a seat, and the auxiliary plate is detachable from the valve body. , the shape can be changed according to the usage conditions,
In addition, it is economically advantageous since it is not necessary to separately manufacture the valve body, and since the auxiliary plate is made of a tough material such as stainless steel, it can withstand use for many years.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an embodiment of the present invention, Fig. 2 is a longitudinal cross-sectional view of the same, Fig. 3 is a cross-sectional view of the same, Fig. 4 is a perspective view of one of the auxiliary plates, and Fig. 5 is a perspective view of the same. A perspective view of the other auxiliary plate, and FIG. 6 is a perspective view showing a modification of the same. 1... Shaft, 2... Valve body, 3... Missing part, 5a,
5b... Auxiliary plate, 7... Rectifying vane plate, 9, 9a...
...straightening vane plate, 10...pipe line.

Claims (1)

[Claims for Utility Model Registration] (1) A circular auxiliary plate made of a highly wear-resistant material is fixed to the opposite front and rear surfaces of the valve body in a notch provided on the outer periphery of the valve body. A butterfly valve characterized in that one auxiliary plate is provided with a plurality of rectifying vanes arranged in parallel, and the other auxiliary plate is provided with a rectifying vane for reducing negative pressure. (2) The butterfly valve according to claim 1, wherein the auxiliary plate is made of stainless steel.