JP2000320781A - Impact pressure-absorbing pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent destroying and deformation of a conduit passage even if a pressure variation of a large scale is generated in the conduit passage by integrally providing an elastic inner cylinder in an outer cylinder connectable to the conduit passage with concentric closed space, forming an opening portion communicating with the closed space on the outer cylinder and providing a pressure control valve on the opening portion. SOLUTION: An inner cylinder 2 comprising synthetic rubber, etc., having an elasticity is disposed in an outer cylinder 1 formed with flanges 1b on both ends with a concentric space S, and flange portions 3 at both ends of the inner cylinder 2 are integrally formed on the flanges 1b of the outer cylinder 1 to close the space S. A through-hole 5 communicating with a closed space S is formed on the outer cylinder 1 and a pressure control valve 6 and a fluid filling valve 7 are connected to the through-hole 5 so that fluid such as air and liquid can be supplied and filled or discharged to/from the space S. When a rapid pressure variation is generated in a conduit passage, a volume of the space S is reduced by an expansion deformation of the inner cylinder 2 and a corresponding amount of fluid to the reduced amount is discharged through the pressure control valve 6. Thereby, a rapid pressure rising in the conduit passage is absorbed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an impact pressure absorbing tube.

[0002]

2. Description of the Related Art Conventionally, if a sudden pressure change such as a water hammer occurs in a pipe line, a pipe joint is damaged or the pipe itself is deformed. This prevents damage to the piping due to pressure rise.

[0003]

The above-mentioned countermeasures against the pressure change correspond to a relatively small-scale pressure change such as a water hammer caused by the opening and closing of a valve, and occur in a wide area in a pipeline network. There was a problem that it could not respond effectively to a large-scale pressure rise. Furthermore, it is impossible to predict in advance where in the pipeline network such a pressure rise will occur, and if such a pressure rise occurs, the weakest point in the pipeline will be damaged. It is impossible to predict where it will be.

[0004] Therefore, measures against accidents such as pipe breakage caused by large-scale pressure fluctuations in the pipe network due to some cause are inevitably ex post measures, and it takes time for restoration work. was there. The present invention
In order to solve the above problems, even if large-scale pressure fluctuations occur in the pipeline, it is necessary to cope with such pressure fluctuations and prevent breakage and deformation of the pipelines. The object of the present invention is to make it possible to identify a damaged portion in advance even if a road is broken, so that restoration work can be performed quickly.

[0005]

According to a first aspect of the present invention, there is provided an impact pressure absorbing tube in which an elastic inner cylinder is integrated with a concentric closed space in an outer cylinder which can be connected to a pipeline, and the outer cylinder is provided with the elastic inner cylinder. An opening communicating with the closed space is formed, and the opening is provided with a pressure control valve for controlling the fluid pressure so that the pressure in the closed space is equal to the fluid pressure in the pipeline. It becomes.

According to the above-mentioned shock pressure absorbing pipe, large-scale pressure fluctuation can be coped with by internal pressure fluctuation through a pressure control valve in a concentric closed space, and fluctuation in pipe internal pressure is widely coped with. Can prevent the damage to the pipeline. The impact pressure absorbing tube according to claim 2 is the impact pressure absorbing tube,
The pressure resistance of the outer cylinder is lower than the pressure resistance of the other pipes constituting the conduit.

[0007] According to this shock pressure absorbing tube, if the pressure fluctuation in the pipeline exceeds the shock absorbing capacity and the damage of the pipeline is unavoidable, the shock pressure absorbing tube portion is actively damaged. This makes it possible to specify in advance the repair location. According to a third aspect of the present invention, in the above-mentioned impact pressure absorbing tube, the pressure control valve is connected to the accumulator tank.

According to this shock pressure absorbing tube, the fluid discharged by pressure absorption when the internal pressure fluctuates in the pipeline is stored in the accumulator tank without being released to the atmosphere, so that exhaust noise can be suppressed. Can be.

[0009]

Next, an embodiment of the present invention will be described. Embodiment 1 FIG. 1 is a sectional view of an impact pressure absorbing tube according to Embodiment 1 of the present invention. In FIG. 1, reference numeral 1 denotes an outer cylinder. In the illustrated example, flanges 1b are formed at both ends, and the flanges 1b can be connected to a pipe 1a constituting a pipeline.

When the pipe 1a is a metal pipe such as a steel pipe or a cast iron pipe, the outer cylinder 1 is made of the same material. Reference numeral 2 denotes an inner cylinder, which is disposed inside the outer cylinder 1 with a concentric space S therebetween, and is integrated with the outer cylinder 1 at end flange portions 3 and 3 to hermetically seal the space S. The inner cylinder 2 is made of an elastic synthetic resin or synthetic rubber, and is elastically deformable by internal pressure.

Reference numeral 4 denotes an inner cylinder holding plate for fixing the inner cylinder 2 to the outer cylinder 1. Although not shown only with a virtual center line of a two-dot chain line, it has a hexagonal hole. The fastener is attached to the surface with bolts or countersunk bolts so that the fastener does not protrude. A through hole 5 is formed in the outer cylinder 1, and a pressure control valve 6 communicates with the through hole 5.

In the figure, reference numeral 7 denotes a fluid filling valve, and a space S
It is for supplying and discharging a fluid such as air and liquid, and is closed except when charging and discharging.
Next, a use state of the first embodiment will be described.
First, the outer cylinder 1 is connected to the pipes 1a, 1a forming a pipe by a flange 1b.

At this time, a seal packing 8 is interposed between the flanges 1b, 1b to prevent leakage from the connection.
After the installation of the pipeline, fluid is supplied to the space S from the fluid filling valve 7 so that the pressure in the space S is substantially equal to the fluid pressure in the pipeline. Thereafter, the fluid filling valve 7 is closed, and the pressure control valve 6 is operated.

After setting in such a state, a sudden pressure fluctuation occurs in the pipe line, and when the pressure fluctuation reaches the shock pressure absorbing pipe, the inner cylinder 2 expands and deforms in response to the pressure, and Reduce the volume of S. The amount of fluid corresponding to this decrease is
It is discharged from the through hole 5 to the outside via the pressure regulating valve.
Therefore, a sudden increase in pressure in the pipeline is reliably absorbed by the impact pressure absorbing tube, and breakage or deformation of the pipeline is prevented. Second Embodiment In an impact pressure absorbing tube according to a second embodiment, the pressure resistance of the outer cylinder 1 in the first embodiment is weaker than the pressure resistance of the tube 1a constituting the conduit.

That is, in the case of a metal pipe such as a cast iron pipe or a steel pipe, the thickness of the outer cylinder 1 is 5% to 10% of the thickness of the metal pipe.
% And the strength is weakened. Further, instead of such a thin metal, the outer cylinder 1 may be made of a material having a weak material such as a plastic tube. According to the impact pressure absorbing tube of the second embodiment, if the sudden increase in pressure in the pipeline cannot be absorbed and breakage or deformation of the pipeline can no longer be prevented, the other pipe 1a of the pipeline is damaged. First, the outer cylinder 1 itself is destroyed, thereby protecting the pipeline and at the same time specifying the damaged portion.

Therefore, even in the case where a breakage accident occurs in the pipeline due to an abnormal increase in the pressure in the pipeline, the damaged portion can be specified and the repair can be performed quickly. Third Embodiment FIG. 2 is a cross-sectional view of a third embodiment, in which members denoted by the same reference numerals as those in FIG. 1 indicate the same members, and detailed descriptions thereof will be omitted.

In the shock pressure absorbing tube according to the third embodiment, a pressure control valve 6 communicating with a space S is communicated with an accumulator tank 9. Therefore, according to the shock pressure absorbing pipe of the third embodiment, when the fluid flowing into and out of the pressure control valve 6, particularly the fluid, is air due to the pressure fluctuation in the pipe, the flow of the fluid is moderated and the noise is reduced.

Further, as another configuration example, the pressure resistance of the outer cylinder 1 of the second embodiment shown in FIG. 2 is set to be lower than the pressure strength of the pipe 1a as in the second embodiment. When it is hung, the outer cylinder 1 can be broken.

[0019]

As described above, according to the shock pressure absorbing pipe of the present invention, the pressure is reduced not only in the partial pressure reduction in the conventional pressure reducing valve but in the wide surface of the entire inner cylinder, so that the shock absorption is achieved. Even if the pressure is high and the pressure fluctuates widely and widely, the impact can be sufficiently reduced.

Further, even if the pressure fluctuation is not completely absorbed, the outer cylinder is broken earlier than the other pipes constituting the pipeline, so that the location where the pipeline is broken can be specified in advance. Repair and restoration can be done quickly. Further, when the accumulator tank is connected to the pressure control valve, the sound of the fluid jetting out and absorption sound generated from the pressure control valve due to the fluctuation in the pipe pressure is eliminated, and the quiet operation becomes possible.

[Brief description of the drawings]

FIG. 1 is a sectional view of an impact pressure absorbing tube according to Embodiment 1 of the present invention.

FIG. 2 is a sectional view of an impact pressure absorbing tube according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer cylinder 2 Inner cylinder 3 End flange 5 Through hole 6 Pressure control valve

Claims (3)

[Claims] 1. An elastic inner cylinder is integrated with a concentric sealed space in an outer cylinder connectable to a pipeline, and an opening communicating with the sealed space is formed in the outer cylinder. A pressure control valve for controlling a fluid pressure so that a pressure in the closed space becomes equal to a fluid pressure in the pipeline. 2. The shock pressure absorbing tube according to claim 1, wherein the pressure resistance of the outer cylinder is lower than the pressure resistance of the other tubes constituting the conduit. 3. The shock pressure absorbing pipe according to claim 1, wherein the pressure control valve is connected to the accumulator tank.