JPH0247638B2 - HAIKANKEINOATSURYOKUMYAKUDOKYUSHUSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a device for absorbing pressure pulsations in a piping system.

[Conventional technology]

In general, when pressure pulsations generated by driving a fluid machine such as a pump propagate to a piping system, vibrations and noise are generated in the piping system. For example, in pump equipment, the water pressure pulsation that occurs when the impeller blades pass through the discharge volute inlet, that is, the number of blades x
Pulsations occur at the frequency of the rotational speed, and these pulsations propagate through the water column within the piping, causing the entire piping system to vibrate and generate noise.

To deal with the occurrence of pulsation as described above,
A variety of pulse devices have been used. For example, installing a branch pipe with a wavelength that is 1/4 times the wavelength of the pressure pulsations occurring in the piping system in the middle of the piping, or attaching a flexible material such as rubber to a part of the inner surface of the piping to suppress the pulsations due to the vibration of this part. There are ways to absorb it. By the way, as a pressure pulsation absorbing device, it is small and does not require a large installation space.
In addition, it is desirable that the material is made of strong materials and structure and has excellent human resistance.

To explain the conventional pressure pulsation absorbing device with reference to FIG. 1, it is constructed by connecting a closed chamber 2 in the middle of a pipe 1, and the chamber 2 and the pipe 1 are connected with a length L and a cross-sectional area a. They are connected via part 3. When this chamber 2 is filled with the liquid in the pipe 1, the eigenvalue f _o of the pressure pulsation in the chamber 2 is becomes. Here, C is indoor compliance,
a is the cross-sectional area of the connection, V is the volume of the chamber, and L' is the length of the connection including the terminal correction.

When the above-mentioned eigenvalue _fo matches the frequency of the pressure pulsations propagating through the piping system, the interior of the room resonates, and the pressure pulsations propagating through the piping system are significantly reduced.

[Problem to be solved by the invention]

Although a pressure pulsation absorbing device based on this principle has been put into practical use for moving air piping, it is not suitable for liquid piping systems that transport clean liquid. This is room 2
Since the cross-sectional area of the connecting part 3 of the pipe 18 and the pipe 18 is small, the chamber 2
There is a problem that the liquid inside stagnates for a long time and deteriorates in quality.

For example, if the above-mentioned pulsation absorbing device is installed in pump piping for waterworks or chemical liquids, it is undesirable for the liquid that has been stagnant inside for a long time to flow out into the piping due to sanitary or chemical problems. It is something.

The object of the invention is to prevent fluid from stagnation in a closed chamber which absorbs pressure pulsations and which is connected to the piping via a capillary.

[Means to solve the problem]

This invention provides a pressure pulsation absorber for a piping system in which a closed chamber for absorbing pressure pulsations is connected to piping via a capillary, in which the capillary tube connecting the closed chamber and the piping is connected at least twice in the direction of fluid flow in the piping. two tubes are arranged so that a pressure difference is created between each thin tube,
The fluid in the closed chamber is circulated through the piping.

[Effect]

With the above configuration, the flow of fluid in the pipe causes a pressure increase at the opening of one capillary and a pressure drop at the opening of the other capillary, creating a pressure difference between the two capillaries. arise. Since the fluid flows from the high pressure section to the low pressure section, the liquid in the closed chamber is directed to the low pressure capillary, and from the high pressure capillary, fresh liquid flowing in the pipe flows. Therefore, the fluid does not stagnate in the closed chamber, and fresh liquid that constantly flows through the piping is supplied to the closed chamber, thereby preventing deterioration of the liquid due to stagnation in the chamber.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 2 to 4.

In FIG. 2, the closed chamber 2 is a capillary tube 3a, 3
It is connected to the outside of the pipe 1 via b. The thin tubes 3a and 3b are arranged to be inclined in different directions with respect to the flow direction of the fluid in the pipe 1. In the figure, the angle θ _a between the thin tube 3 a and the fluid flow direction of the pipe 1 is θ _a <90°, and the angle θ _b between the thin tube 3 b and the fluid flow direction of the pipe 1 is θ _b >90°. It's getting old. Therefore, when the fluid is flowing in the direction of the arrow in the pipe 1, the pressure at point A of the pipe 3a is higher than the pressure at point B of the thin tube 3b. For this reason, A
The fluid at point B enters the closed chamber 2 and the same amount of fluid exits at point B. Therefore, the fluid in the closed chamber 2 does not stagnate but always flows due to the pressure difference.

As a result, fresh fluid in the pipe 1 is constantly guided to the closed chamber 2, so that the fluid is prevented from corroding or deteriorating due to stagnation.

FIG. 3 shows another embodiment of the invention. In this case, a closed chamber 2 is placed around the outer circumference of the pipe 1.
are arranged, and the thin tubes 3a and 3b are provided to protrude from the inner surface of the pipe 1, and the protruding ends C and C' of the thin tubes 3a and 3b are inclined in different directions with respect to the flow direction of the fluid in the pipe 1. ing. That is, the angle θ _a between the normal direction of the end surface C of the thin tube 3 a and the flow direction of the fluid in the pipe 1 is θ _a <90°, and The angle θ _b with the fluid flow direction is θ _b >90°, and the same effect as in the embodiment shown in FIG. 2 can be achieved.

Further, FIG. 4 shows still another embodiment of the present invention.

In this case, a closed chamber 2 is arranged around the outer periphery of the pipe 1 as in the embodiment shown in FIG.
It is connected to piping 1. Thin tube 3a of piping 1
A protrusion is provided on the downstream side of the tube 3b and on the upstream side of the thin tube 3b. As a result, when the fluid in the pipe 1 flows in the direction of the arrow, a pressure difference can be created in which the pressure at point A of the thin tube 3a is higher than the pressure at point B of the thin tube, as shown in FIGS. Almost the same effect as in the embodiment can be obtained.

〔Effect of the invention〕

As explained above, according to the present invention, at least two thin tubes connecting the closed chamber that absorbs pressure pulsations and the piping are arranged in the direction of fluid flow in the piping, so the liquid in the closed chamber is always fresh. Corrosion or deterioration of fluid due to stagnation can be prevented.

[Brief explanation of drawings]

FIG. 1 is a front view showing a conventional pressure pulsation absorbing device, and FIGS. 2 to 4 are partial sectional views showing the pressure pulsation absorbing device of the present invention. 1...Piping, 2...Room, 3...Connection.

Claims (1)

[Scope of Claims] 1. In a pressure pulsation absorbing device for a piping system in which a closed chamber for absorbing pressure pulsations is connected to piping via a capillary, the capillary tube connecting the closed chamber and the piping is connected to the fluid in the piping. A pressure pulsation absorbing device for a piping system, characterized in that at least two thin tubes are arranged in the flow direction of the tube so that a pressure difference is generated between the tubes, and the fluid in the closed chamber is circulated through the tube. . 2. Claim 1, characterized in that at least two thin tubes connected to the piping are inclined in different directions with respect to the flow direction of the fluid in the piping, thereby creating a pressure difference between the thin tubes and the thin tubes. Pressure pulsation absorbing device for the piping system described in . 3 The end surfaces of at least two capillary tubes connected to the piping are provided protruding into the piping, the end surfaces of the capillary tubes are inclined in different directions with respect to the flow direction of the fluid in the piping, and pressure is created between the capillary tubes and the capillary tubes. A pressure pulsation absorbing device for a piping system according to claim 1, characterized in that the pressure pulsation absorbing device for a piping system generates a difference. 4. Protrusions are provided on the downstream side of the inner surface of the pipe of the upstream capillary opening and the upstream side of the inner surface of the pipe of the downstream capillary opening of the at least two capillary tubes connected to the pipe to create a pressure difference between the capillary tubes. A pressure pulsation absorbing device for a piping system according to claim 1.