JP3016283B2 - Water hammer shock absorber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorber for damping the impact of a water hammer (water hammer) and reducing noise.

[0002]

2. Description of the Related Art Generally, a water hammer (phenomenon) occurs when a steady flow by a pump is suddenly stopped or when the pump is started. This phenomenon is accompanied by an increase in the size of a piping system and a building, and the effect (damage) when it occurs also increases. That is, as a result of the pressure wave (shock wave) generated by the water hammer reciprocating in the pipeline, in the worst case, the pressure wave may damage the valve or a part of the pipeline. In addition, a loud sound is generated as a result of the reciprocation of the pressure wave, which is a new noise problem. Conventionally, various measures have been taken to prevent this water hammer,
Neither is a sufficient measure.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a device capable of buffering an impact generated by a water hammer and reducing a generated sound.

[0004]

SUMMARY OF THE INVENTION The present invention has been completed based on the idea of converting the energy of a pressure wave into the kinetic energy of a fluid in order to cushion the impact caused by a water hammer. An annular flow path having a diameter larger than that of the circular flow path, which is located between the circular flow paths at both ends, and at least on the outer periphery of the main pipe whose flow path is bent from the circular flow path to the annular flow path, It is characterized in that one outer peripheral pipe is provided to form a buffer space between the two pipes, and a liquid is sealed in the buffer space.

When this device is connected to a pipe, a pressure wave generated by a water hammer collides with a curved wall of a flow path formed by a circular flow path and an annular flow path of the main body pipe and changes its direction. Is transmitted to the fluid enclosed in the buffer space. Since the sealed fluid has a function of absorbing collision energy, it reduces pressure waves and impulsive sounds and prevents adverse effects of the water hammer. Even if the pressure wave reciprocates in the pipeline with the buffer portion as one reciprocating end, this shock absorbing effect is obtained every time the pressure wave is transmitted to the wall of the bent portion of the flow path of the main pipe. Can be rapidly attenuated to eliminate the impact of the water hammer.

[0006] In the buffer space, particles made of a material having a high specific gravity, for example, lead can be sealed together with the liquid. According to this configuration, the energy of the pressure wave can be changed to the kinetic energy of the high specific gravity particles, and the collision of these particles can further effectively buffer the water hammer.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
1 and 2 show one embodiment of a water hammer shock absorber 10 of the present invention. The water hammer shock absorber 10 includes a main body pipe 11 and an outer peripheral pipe 12. The main body pipe 11 has connection flanges 13 at both ends, and has a circular flow path 14 at the center of the connection flange 13. And the circular channels 14 at both ends
The central solid body 15 is located between the two, and an annular flow path 17 having a diameter larger than that of the circular flow path 14 is formed between the central solid body 15 and the outer peripheral wall 16. Reference numeral 18 denotes a connecting leg connecting the center solid body 15 and the outer peripheral wall 16. The central solid body 15 has a cone 15a that is pointed to the left and right,
The diameter of the flow path is gradually and smoothly increased from the circular flow path 14 to the annular flow path 17. That is, in the present water hammer shock absorber 10, the flow path of the main body pipe 11 is bent from the circular flow path 14 to the annular flow path 17.

The outer peripheral pipe 12 forms a liquid-tight buffer space 20 on the outer periphery of the outer peripheral wall 16 of the main pipe 11, and is joined to the main pipe 11 by means such as welding. The connection flange 1 is provided in the buffer space 20.
The liquid 22 is sealed through the liquid sealing hole 21 formed in the liquid crystal 3. The liquid filling hole 21 is closed after filling the liquid.

The present water hammer shock absorber 10 having the above-described structure is used by being connected to a flow path including a pump P and a connection pipe C as shown in FIG. Now, when the pump P is rapidly closed in a state where a steady flow is generated in these flow paths, a pressure wave is generated by the water hammer, and the pressure wave propagates to the water hammer buffer device 10. Then, this pressure wave first collides with the outer peripheral wall surface of the cone 15 a in the center pipe 11 of the water hammer shock absorber 10 and turns radially outward, and the outer peripheral wall 16
Collide with The pressure wave colliding with the outer peripheral wall 16 is reflected again and transmitted to the central solid body 15, and the pressure wave reciprocates between the central solid body 15 and the outer peripheral wall 16. In the process of reciprocation of the pressure wave, the energy is transmitted to the liquid 22 in the buffer space 20 through the outer wall 16. Since the liquid 22 has an excellent energy absorbing action, the energy of the water hammer is attenuated in the water hammer shock absorber 10. That is, according to the present water hammer damping device 10, it is possible to dampen the impact and the accompanying sound.

The pressure wave caused by the water hammer is shown in FIG.
, The pump P and the water hammer shock absorber 10
It is also possible to go back and forth between However, each time the reciprocating pressure wave reaches the water hammer shock absorber 10, the above-described buffering action is expected. Therefore, for example, as compared with a case where another pump P is located instead of the water hammer shock absorber 10, for example. The pressure wave can be attenuated much more quickly.

The connecting pipe C may be a normal pipe,
It is preferable to use a sound deadening pipe 30 having a structure shown in FIG. The silencing pipe 30 has an outer pipe 32 provided concentrically on the outer circumference of an inner pipe 31, and a liquid 34 is sealed in a buffer space 33 formed between the pipes 31 and 32. At both ends of the inner pipe 31 and the outer pipe 32, connection flanges 35 are provided. According to the silencing pipe 30, a silencing effect can be obtained in which the sound caused by the pressure wave collision is prevented from leaking to the outside.

In the liquid 22 in the buffer space 20, particles made of a material having a high specific gravity such as lead can be sealed. The energy of the pressure wave is transmitted to the high specific gravity particles to become kinetic energy, and is further attenuated by the collision of these particles.

In the above embodiment, a single buffer space 20 is formed outside the main pipe 11, but a plurality of buffer spaces 2 are formed.
0 may be formed and the liquid 22 may be sealed in each of them.

[0014]

As described above, according to the present invention, the impact generated by the water hammer can be absorbed,
Damage to the pump or the like due to impact can be prevented, and impact noise can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a water hammer shock absorber according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a pipeline diagram schematically showing reciprocation of a pressure wave by a water hammer.

FIG. 4 is a longitudinal sectional view showing a pipe structure for connecting a water hammer shock absorber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Water hammer shock absorber 11 Main body pipe 12 Outer peripheral pipe 13 Connection flange 14 Circular flow path 15 Central solid body 15a Conical body 16 Outer peripheral wall 17 Annular flow path 20 Buffer space 22 Liquid

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16L 55/04-55/05 F16L 55/02 F16L 55/033 F15B 1/04

Claims (3)

(57) [Claims] 1. A circular flow path at both ends and an annular flow path located between the circular flow paths at both ends and having a larger diameter than the circular flow path. A water hammer shock absorber, wherein at least one outer circumferential pipe is provided on an outer circumference of a main pipe whose path is bent to form a buffer space between the two pipes, and a liquid is sealed in the buffer space. 2. The water hammer shock absorber according to claim 1, wherein the buffer space is filled with liquid and granules made of a material having a high specific gravity. 3. The water hammer shock absorber according to claim 1, wherein the inner pipe communicates with the main body pipe.
A water hammer damper connected to a muffler pipe having an outer pipe concentric with the inner pipe and a liquid sealed in a buffer space between the two pipes.