JPS6165979A - Low noise valve - Google Patents

Abstract

PURPOSE:To produce a noise preventing effect, by a method wherein fluid is caused to flow through gaps between fillers serving as a silencing material. CONSTITUTION:A valve body 22 is provided with a downstream side passage 40 formed concentrically to a cage 27, and plural partitions 44, 45, 46, and 47, each made of a porous plate, are located to the inner peripheral wall of the passage 40. The interiors of inner chambers 48, 49, 50, and 51, partitioned by partitions 44, 45, 46, and 47, are closely filled with steel balls 54, serving as a filler for silencing. The size of the steel ball 54 is increased gradually toward the downstream side. This constitution, since fluid flows through gaps between the fillers, diminishes kinetic energy of fluid, resulting in production of a noise preventing effect.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a low-noise valve capable of reducing and preventing noise generated by fluid pressure reduction, high-speed fluid flow, etc.

[Prior art]

In general, when a valve provides resistance to the flow of fluid, undesirable noise may be generated due to turbulence in the flow that occurs at the throttle portion of the valve. FIG. 2 is a vertical cross-sectional view of a conventional cage valve shown to explain the noise generation. To explain this based on the figure, the valve body 1 has an upstream flow path 3 connected to the inside by a partition wall 2. A cylindrical cage 7 and a seat ring 8 are disposed between the partition wall 2 and the top cover 6, which is fitted into the upper opening end of the downstream flow path 4 and fixed with bolts 5. and are fitted through pins 9 and 10. On the peripheral wall of the cage 70, there are ga windows 11 that connect the inside of the cage 7 and the upstream flow path 3, and the windows 11 are formed in a T-shape in the wide part and the narrow part. There is. Further, a lower open end of the seat ring 8 is opened to the downstream flow path 4 . A valve plug 14 is slidably fitted into the inner hole of the cage 7 and is attached to the lower end of the valve stem 13 which is slidably passed through the upper cover 6 via a packing 12. At the lower end of the plug 14, an underwear seat 16 is provided which seats on a valve seat 15 provided at the upper end opening of the seat 17 ring 8 when fully closed. Further, an upper seating portion 18 is provided on the outer circumferential portion of the upper end of the valve plug 14, and is seated on the valve seat 17 formed on the inner circumferential surface of the cage 7 when the valve plug 14 is fully closed.

In such a configuration, the valve is operated by actuation of the drive by an automatic control device or by manual operation? When a13 is moved up and down, the valve plug 14 moves together with the valve plug 14 to change the degree of opening of the window 11, that is, the opening area, thereby removing the window 11 of the cage 7 and the seat ring 8 from the upstream flow path 3. The flow rate of the controlled fluid flowing through the downstream channel 4 is controlled.

[Problem that the invention seeks to solve]

In the flow rate control using the cage valve as described above, when fluid flows from the window 11 downward to the valve plug 14 while being depressurized as shown by the arrow, the inflowing fluid entrains the surrounding fluid and causes turbulence. This causes high frequency noise. Furthermore, this noise also propagates to the downstream piping section, so there is a drawback that it leaks to the outside and worsens the noise.

Therefore, in the past, Japanese Patent Application No. 51-040930,
-050614 etc., inside both upstream and downstream channels 3.4,
It has been proposed to fill a cylindrical body provided inside the valve plug 14 and below the seat ring 8 with spheres to reduce the kinetic energy of the fluid, thereby preventing noise generation. A satisfactory silencing effect cannot be expected, and if the silencing section is unavoidably lengthened in order to increase the silencing effect, the valve as a whole becomes larger. Furthermore, other low-noise valves have been proposed in addition to filling with spheres, but these have not yielded effective results.

The present invention has been devised in view of the above points, and provides a low-frequency sound valve that reliably prevents the generation of noise and is breathable.

[Means for solving problems]

In the low-noise valve according to the present invention, the F flow side flow path of the valve body is formed concentrically with the cylindrical cage, and the L flow path is partitioned by a partition plate made of a plurality of perforated plates. The space between the plates is filled with a sound-deadening filler such that the size of the filler gradually increases from the upstream side to the downstream side.

[Effect]

In the present invention, the gaps in the complicated flow path between the sound-absorbing fillers gradually increase from the upstream side to the downstream side, thereby promoting expansion of the volume of the fluid and suppressing and preventing the generation of noise.

Hereinafter, embodiments of the invention will be described in detail based on the drawings.

〔Example〕

FIG. 1 is a longitudinal sectional view showing an embodiment of a low noise valve according to the present invention. ? The valve body 22 of the low noise valve 21 is provided with an upstream passage 23 that opens horizontally and is flanged to an upstream pipe (not shown). An upper cover 24 is joined to the upward opening of 22 and fixed with bolts 25 and nuts 26. Reference numeral 27 denotes a cage formed in a cylindrical shape and fitted inside the valve body 22 below the upper lid 24. A gasket 28 is inserted between the cage 27 and the upper lid 24). Fixed. A plurality of windows 29 are provided on the peripheral wall of the cage 27.
is opened to form a peripheral wall opening, and this window 29 connects the upstream passage 23 surrounding the cage 27 with the inside of the cage 27.

The lower end of a valve stem 31 is screwed into a cylindrical valve plug 30 that is slidably fitted into the inner hole of the cage 27. This valve stem 31 is inserted through a packing 33 in a packing box 32. and is pivotally supported by the upper lid 24. 34Vi Pasokin 3
2 is a packing presser that presses the inner bottom surface of the bankin box 32. Reference numerals 35 and 36 designate upper and lower seat portions that are provided on the upper and T portions of the square plug 30 and seated on the valve seats 37 and 38 on the gauge 27 side, respectively. When the valve plug 30 is raised or lowered, the flow rate of the cage 29 changes, and the flow of fluid flowing from the upstream passage 23 through the window 29 into the cage 27 is adjusted.

θ11 on the valve body 22d1. A lower IWtllQ flow path 4 is formed substantially perpendicular to the side flow path 23 and concentrically with the cages 2 and 7.
0, and its lower end flange portion 41 is connected to a downstream pipe line (not shown). This downstream flow path 40 is formed in the shape of a conical head whose diameter gradually increases in the direction of fluid flow. It communicates with the inside of the cage 27 through the hole 43. Furthermore, the downstream flow path 40 is partitioned into four inner chambers 48 by partition plates 44, 45, 46, and 47, which are made up of a plurality of (four in this embodiment) perforated plates having buttons fused to the inner peripheral wall thereof. ,49,50.51
are formed, and each of these inner chambers is closely filled with steel balls 54 shown as an example of a noise-reducing filler with a gap formed between them for passage of fluid. The diameters of the steel balls 54 in each of the inner chambers are different, and are set to gradually increase from the upstream side, that is, the uppermost inner chamber 48, to the downstream side, that is, the lowermost inner chamber 51. .

The operation of the low noise valve having the button configuration as described above will be explained. When the valve stem 31 is moved up and down by the actuation of a drive unit by an automatic control device or by manual operation, the valve plug 30 moves together with this, and the opening degree, that is, the opening area of the window 29 changes.
This controls the flow rate of fluid flowing from the upstream flow path 23 through the window 29 of the cage 27 to the downstream flow path 40. The fluid in the downstream flow path 40iC':B is the steel ball 5.
It flows through the gap between 4.

In this way, the stream -1δ2 is transferred from the upper fifth side flow path 23 to the downstream 1lIII flow path 4o.
As the body flows and moves, the fluid flowing in while reducing the pressure from the window 29 as described above engulfs the fluid on the fbt side.
The flow becomes turbulent and noise due to high frequencies is generated. This noise then tries to propagate to the outside via the side flow path 4o, but there are many
β (Since the spheres 54 are densely illuminated by light j+4, the fluid flowing into the F flow path 40 greatly reduces its kinetic energy as it flows down the complex flow path between the steel balls 54. f!?Miscellaneous fx between the steel balls 54 as it goes downstream
Since the flow passages gradually become larger, the volume expands, and as a result, the effect of reducing or preventing the generation of noise can be obtained.

FIG. 3 is a diagram illustrating the desired pressure drop of fluid through downstream flow path 40. In this case, the partition plate (42, 44-4
It is obvious that the pressure drop curve can be freely changed by changing the interval, number, diameter of the steel balls 54, etc. of 7).

FIG. 4 is a perspective view of a sound-deadening filling body showing another embodiment of the present invention. The tube piece 6o is short and small as shown in the diagram. This tube piece 60
is made by cutting stainless steel pipes into small pieces, and when filled with them, a gap is formed between them for fluid to pass through, similar to a steel ball, so it has a fluid flow function and a noise-reducing effect, and because it is a hollow material. , the weight is significantly reduced compared to steel balls, reducing the weight of the entire valve.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, in a low-noise valve, the downstream flow path of the valve body is formed approximately concentrically with the cylindrical cage, and a plurality of A porous partition plate is provided, and a plurality of sound-deadening fillers are filled between each partition plate so that the shape and dimensions gradually increase from the upstream side to the downstream side, and the fluid passes through the gaps between the fillers. , the kinetic energy of the fluid flowing down the complicated flow path between these packing bodies can be greatly reduced, and as the gap in the complicated flow path gradually increases, the volume of the fluid also expands. Multi-stage pressure reduction system. Therefore, a sound reduction effect and a noise prevention effect are obtained, quiet operation is realized, and the environment is improved.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of the low-noise valve according to the present invention, FIG. 2 is a vertical cross-sectional view showing an example of a conventional cage valve, and FIG. 3 is a pressure drop of the low-noise valve according to the present invention. Figure 4 showing
The figure is a perspective view of a sound-deadening filling body showing another embodiment of the present invention. 21... Lu low noise valve, 27... cage, 29...
Φ・Window, 40...Downstream flow path, 42.44,45.
46.47・e-9 porous partition plate, 54・φ・・steel ball, 6
0・φ・・Tube body.

Claims (1)

[Claims] A downstream flow path of the valve body through which the fluid flowing in from the peripheral wall opening of the cylindrical cage passes toward the downstream pipe path is formed approximately concentrically with the cage, and this flow path is connected to a plurality of perforated plates. 1. A low-noise valve, characterized in that the valve is partitioned by a partition plate consisting of: and a noise-reducing filler is filled between each partition plate so that the shape and size thereof gradually increase from the upstream side to the downstream side.