JPH08135729A - Piping system vibration reducing device - Google Patents

Abstract

PURPOSE: To prevent damage and leakage of inner fluid body, by installing a vibration reducing device by which natural frequency of a small radius pipe can be varied on the small radius pipe and by inhibiting co-vibration with variable frequency component in the small radius pipe. CONSTITUTION: An analyzing device 6 for analyzing measurement data obtained from both vibration measuring devices 3, 4, a diagnostic device 7 for diagnosing co-vibration based on the analyzed result, and a vibration reducing devices 5a, 5b for making the natural frequency of the small radius pipe 2 changed based on the diagnostic data are provided, and a base pipe vibration measuring device 3 and a small radius pipe vibration measuring device 4 are respectively installed on the base pipe 1 and the small radius pipe 2 as well, in a piping system which is composed of a large caliber base pipe and a small radius pipe which is smaller in caliber than the base pipe and is connected with the base pipe.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to reducing the vibration of a piping system, and in particular, it suppresses the resonance vibration generated in the small diameter pipe connected to a mother pipe that receives a load having a variable frequency component, thereby ensuring the soundness of the small diameter pipe. The present invention relates to a piping system vibration reduction device that maintains

[0002]

2. Description of the Related Art A large number of pipes (hereinafter referred to as mother pipes) containing a high-temperature and high-pressure fluid (steam, hot water) are installed in various plants. A large number of small-diameter pipes (hereinafter referred to as small-diameter pipes) are connected to these mother pipes for measuring pressure, temperature, etc., or for removing the contained fluid from the mother pipes.

Generally, when the contained fluid leaks from these small-diameter pipes and the leak amount exceeds a specified value, the operation of the plant or the like must be stopped, and such a situation will always occur. This causes great damage in important plants such as power plants where stable operation is required.

Factors that cause leakage in small-diameter piping include
When the load input to the small diameter pipe and the small diameter pipe resonate,
Since an excessive vibration load is applied to the small-diameter pipe, a resonance phenomenon in which a welded portion is cracked and the contained fluid leaks from the crack is considered.

[0005]

With respect to the resonance phenomenon, which is one of the factors that cause cracks and contained fluid leakage in small-diameter pipes, in order to avoid the occurrence of resonance in the design of pipes, The position of the pipe support device that supports the small diameter pipe in the building or the like is determined in consideration of the frequency that can occur in the pipe system.

However, in a piping system to which a vibration having a fluctuating frequency component is applied, there is always a resonating frequency region in the current pipe supporting apparatus, and therefore, when the resonance frequency is continuously operated for a long period of time. Therefore, it is considered that cracks are more likely to occur at welded portions of small-diameter pipes.

An object of the present invention is to install a vibration reducing device in a small diameter pipe capable of varying the natural frequency of the small diameter pipe to suppress resonance with a fluctuating frequency component in the small diameter pipe to prevent damage and inclusion fluid. An object of the present invention is to provide a piping system vibration reduction device that prevents leakage.

[0008]

In order to achieve the above object, a piping system vibration reducing apparatus according to the invention of claim 1 has a large diameter mother pipe and a small diameter pipe smaller than the mother pipe connected to this mother pipe. In a piping system consisting of, a mother pipe vibration measuring device is installed in the mother pipe, and a small diameter pipe vibration measuring device is installed in a small diameter pipe, and an analysis device that analyzes the measurement data obtained by both vibration measuring devices, and its analysis result. And a vibration reducing device for changing the natural frequency of the small diameter pipe based on the diagnostic data.

According to a second aspect of the present invention, there is provided the piping system vibration reducing device, wherein the vibration reducing device provided in the small diameter pipe for changing the natural frequency is a supporting device for varying the spring constant in supporting the pipe. The piping system vibration reduction device according to claim 1, which is characterized in that. According to a third aspect of the present invention, in the piping system vibration reducing device, the vibration reducing device provided in the small-diameter pipe for changing the natural frequency is a supporting device for varying the pipe fixing force of the pipe support. To do.

According to a fourth aspect of the present invention, there is provided a piping system vibration reducing device, wherein the vibration reducing device for changing the natural frequency provided in the small diameter pipe is a variable supporting device for changing the pipe supporting position. To do. According to a fifth aspect of the present invention, in the piping system vibration reducing device, the vibration reducing device for changing the natural frequency provided in the small diameter pipe is configured so that the outer diameter of the small diameter pipe is doubled and the small diameter pipe is injected into the inside. The partial weight of is variable.

According to a sixth aspect of the present invention, there is provided a piping system vibration reducing device, wherein the substance used for the vibration reducing device is an elastic substance that absorbs heat transfer of the pipe due to vibration and thermal expansion during an earthquake. To do. In the piping system vibration reducer according to the invention of claim 7, the analysis device calculates the stress of the small diameter pipe by using the measurement data obtained from the mother pipe vibration measuring device as an input load to the small diameter pipe to calculate the stress of the small diameter pipe. It is characterized by conducting soundness evaluation.

A pipe system vibration reducing apparatus according to an eighth aspect of the present invention is diagnosed as an analyzing apparatus based on measurement data of a mother pipe vibration measuring apparatus and a small diameter pipe vibration measuring apparatus when a vibration of a certain frequency occurs in a small diameter pipe. Save the optimal natural frequency data for resonance prevention in small diameter piping obtained by the device,
It is characterized in that a database unit is provided for providing the stored optimum natural frequency data to the diagnostic device when the vibration of the relevant frequency occurs again.

[0013]

According to the first aspect of the invention, the measurement data input from the vibration measuring device for the mother pipe and the small diameter pipe is analyzed by the analyzing device,
Based on the analysis data, the diagnostic device diagnoses the resonance vibration in the small diameter pipe, and issues a command to change the natural frequency of the small diameter pipe to the vibration reduction device that supports the small diameter pipe in the building or the like based on the diagnostic data. As a result, the vibration reduction device changes the natural frequency of the small-diameter pipe, so that vibration due to resonance is suppressed and vibration in the piping system is reduced.

According to a second aspect of the present invention, as a vibration reducing device for a small diameter pipe, it is possible to change a spring constant in a supporting device for supporting the small diameter pipe in a building or the like. By the command to change the natural frequency,
By changing the spring constant that supports small diameter piping,
The natural frequency of the small-diameter pipe changes to suppress resonance.

According to a third aspect of the invention, as a vibration reducing device for a small diameter pipe, it is possible to change the supporting force for the small diameter pipe in a supporting device for fixing the small diameter pipe to a building or the like, and the diagnosis is performed when the small diameter pipe resonates. By changing the supporting force for supporting the small diameter pipe in response to the change command of the natural frequency from the device, the natural frequency in the small diameter pipe changes and resonance is suppressed.

According to a fourth aspect of the present invention, as a vibration reducing device for a small diameter pipe, it is possible to change a supporting position in a variable supporting device for supporting the small diameter pipe, and when the small diameter pipe resonates, a natural vibration from the diagnostic device. By moving the support position that supports the small diameter pipe in response to the number change command, the natural frequency of the small diameter pipe changes and resonance is suppressed.

The invention according to claim 5 is a vibration reducing device for a small-diameter pipe, which enables the partial weight of the small-diameter pipe to be changed.
When the small-diameter pipe resonates, an elastic substance is injected into the double pipe formed between the outer pipe provided on the outer circumference of the small-diameter pipe by a change command of the natural frequency from the diagnostic device. The natural frequency in the pipe changes and resonance is suppressed.

According to a sixth aspect of the present invention, in an apparatus for reducing vibration of a small diameter pipe, an elastic material is interposed in a support system for a building or the like of the small diameter pipe, so that vibration during earthquake or heat transfer due to thermal expansion of the small diameter pipe is elastic material. Absorbs, so unnecessary vibration and stress are not applied to the small diameter pipe.

According to a seventh aspect of the present invention, in the analysis device, the measurement data obtained from the mother pipe vibration measuring device is used as an input load to the small-diameter pipe to calculate stress of the small-diameter pipe, thereby reducing fatigue of the small-diameter pipe. Perform soundness evaluation.

According to the invention as set forth in claim 8, when vibration of a certain frequency is generated in the small diameter pipe, the measurement data of the mother pipe vibration measuring device and the small diameter pipe vibration measuring device are used to analyze by the analyzing device, the diagnosing device and the vibration reducing device. Resonance suppression is implemented in response to this, but the optimum natural frequency data for resonance suppression obtained at this time is stored in the database unit.

The stored optimum natural frequency data is provided to the diagnostic device from the database unit when the vibration of the relevant frequency occurs again in the small diameter pipe, and the vibration reducing device immediately detects the vibration of the small diameter pipe. Vibration is suppressed.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. As shown in the block configuration diagram of the piping system vibration reduction device of FIG. 1, a mother pipe vibration measuring device 3 and a small diameter pipe vibration measuring device 4 are installed in each of the mother pipe 1 and the small diameter pipe 2, and further,
The support portion of the small diameter pipe 2 is fixed to a building or the like via vibration reduction devices 5a and 5b.

The mother pipe vibration measuring device 3 and the small diameter pipe vibration measuring device 4 are connected to a pipe analyzing device 6 for evaluating the stress of the small diameter pipe 2 based on the vibration measurement data measured respectively. ing.

Further, from the stress evaluation, whether or not resonance occurs in the mother pipe 1 and the small diameter pipe 2 is diagnosed, and when the resonance is diagnosed, the vibration reducing devices 5a, 5
The diagnostic device 7 outputs a command signal for changing the natural frequency of the small-diameter pipe 2 to b, and the database unit 8 stores the resulting data when the resonance is converged by the operation of the vibration reducing devices 5a and 5b. There is.

There are various configurations for the vibration reducing devices 5a and 5b, and the first embodiment is shown in the partially cut configuration diagram of FIG. One end of the supporting device 9 to which the small diameter pipe 2 is fixed is connected to one side of the vibration reducing device 10, and the other side of the vibration reducing device 10 is fixed to a building or the like.

The vibration reducing device 10 for varying the natural frequency of the small diameter pipe 2 is a combination of a spring constant changing device 11 and a driving device 12. The spring constant changing device 11 is made of an elastic material 13 such as oil or spring. Schilling 14 and piston
15 and the schilling 14 is fixed to the small diameter pipe 2 via the supporting device 9. The piston 15 is connected to a drive device 12 that moves its position, and the drive device 12 is fixed to a building or the like.

The drive unit 12 moves the position of the piston 15 back and forth in response to a change command signal of the natural frequency from the diagnosis unit 7. As a result, the spring constant of the elastic material 13 in the spring constant changing device 11 changes, the force for supporting the small diameter pipe 2 from the building or the like via the support device 9 changes, and the natural frequency in the small diameter pipe 2 changes.

Next, the operation of the vibration reducing device for the piping system will be described with reference to an example in which the vibration reducing devices 5a and 5b are replaced with the vibration reducing device 10 of the first embodiment. In the piping system in which the small-diameter pipe 2 is connected to the mother pipe 1, when the resonance vibration occurs due to the weight input to the small-diameter pipe 2, the vibration displacement of the small-diameter pipe 2 becomes larger than that when no resonance occurs. Therefore, the stress value generated in the small diameter pipe 2 increases.

The vibration displacement in the small diameter pipe 2 is detected by the small diameter pipe vibration measuring device 4, and the vibration displacement of the mother pipe 1 is detected by the mother pipe vibration measuring device 3 and both are inputted to the analyzing device 6. . The analysis device 6 evaluates the stress of the small diameter pipe 2 from the sent data, and the result is evaluated by the diagnostic device 7
To communicate. The diagnostic device 7 monitors the vibration displacement and stress value of the small diameter pipe 2 to diagnose whether resonance has occurred.

When resonance occurs at this time, the vibration displacement of the small diameter pipe 2 is 1/2 h times the vibration displacement of the mother pipe 1. In addition, h represents the damping constant in the small diameter pipe 2. When the diagnostic device 7 diagnoses that resonance is occurring, it outputs a command signal for changing the natural frequency in the small diameter pipe 2 to the vibration reduction device 10. The vibration reduction device 10 receiving this change command signal operates so as to change the natural frequency of the small diameter pipe 2.

That is, in the vibration reduction device 10, the drive device 12 is actuated and the position of the piston 15 is moved in response to the inputted natural frequency change command signal from the diagnostic device 7. As a result, the force that the elastic material 13 receives in the spring constant changing device 11 changes, and the spring constant as the spring constant changing device 11 changes, so the force that supports the small diameter pipe 2 via the support device 9 changes. Since the natural frequency of the small diameter pipe 2 is changed, the resonance generated in the small diameter pipe 2 is converged.

The result of the resonance convergence is detected by the mother pipe vibration measuring device 3 and the small diameter pipe vibration measuring device 4, the vibration condition of the mother pipe 1 and the small diameter pipe 2 is measured again, and the analyzing device 6 is analyzed. Then, the diagnosis device 7 diagnoses that resonance does not occur.

If the resonance is converged, the diagnostic device 7
Maintains the state of the vibration reduction device 10 at this time, and the data at this time is stored in the database unit 8. When the resonance is not converged, the diagnostic device 7 moves to the vibration reduction device 10
In contrast, a change instruction signal for changing the natural frequency of the small diameter pipe 2 is output.

By repeating the resonance suppressing operation of the small diameter pipe 2 in the vibration reducing device 10 as described above, the resonance phenomenon occurring in the small diameter pipe 2 is prevented.
A large stress is not applied to the cracks, and in particular, cracks are not generated particularly in the welded portion and the leakage of the contained fluid is not generated.

A second embodiment of the vibration reducing device is shown in the perspective view of FIG. This vibration reducing device 16 is realized by changing the supporting force of the small diameter pipe 2 in order to change the natural frequency of the small diameter pipe 2, and the wire 18 for fixing and supporting the small diameter pipe 2 and the driving of the wire 18. The mechanism 19 and the drive device 20 that changes the position of the drive mechanism 19 to change the supporting force of the small diameter pipe 2 by changing the tension of the wire 18.

In the vibration reduction device 16, the drive device 20 moves the position of the drive mechanism 19 in the direction of the arrow in response to the change command signal of the natural frequency from the diagnosis device 7 to change the supporting force of the small diameter pipe 2. . As a result, the natural frequency of the small-diameter pipe 2 changes, and therefore, as in the case of the first embodiment,
Resonance generated in the piping system is suppressed.

A third embodiment of the vibration reducing device is shown in the front view of FIG. The vibration reduction device 21 includes a variable support device 22 that changes the support position of the small diameter pipe 2 by sliding through the rail 2a, and a drive device that moves the variable support device 22.
It consists of 23. Incidentally, here, the variable support device 22
One end of is not directly fixed to the building or the like, but is fixed to the building or the like via a rail 22a by, for example, a support device 24 that buffers and supports.

The function of the vibration reducing device 21 having the above-described structure is that when the resonance phenomenon occurs in the small diameter pipe 2, the diagnostic device 7 issues a command signal for changing the natural frequency to the driving device 23. In response to this, the drive device 23 is operated by the rail 2a and the rail 22.
The variable support device 22 is moved in the arrow direction between a.

As a result, the supporting position of the small diameter pipe 2 by the variable supporting device 22 changes, so that the natural frequency of the small diameter pipe 2 changes and the resonance vibration is suppressed and stopped. In addition,
In the support device 24 that buffers and supports the variable support device 22 when the variable support device 22 moves, if the support force of the small diameter pipe 2 with respect to the building or the like is temporarily relaxed, the sliding operation of the variable support device 22 becomes easy. Further, the supporting force of the small diameter pipe 2 during operation can be buffered and supported by the supporting device 24.

A fourth embodiment of the vibration reducing device is shown in the sectional view of FIG. Note that FIG. 5A is an overall view, and FIG.
FIG. 5B is a view on arrow AA of FIG. The vibration reducing device 25 has a double pipe structure in which an outer pipe 26 is installed at an appropriate position on the outer circumference of the small diameter pipe 2, and a transfer pump 28 is inserted from the elastic substance holding tank 27 into the outer pipe 26. The pipe 29 and the discharge valve 30 are connected to each other. In the elastic substance holding tank 27, an elastic substance 13 such as oil or water is stored.

Next, the operation of the above configuration will be described. When the resonance phenomenon occurs in the small-diameter pipe 2, the diagnostic device 7 issues a command signal for changing the natural frequency to the drive device 25.
The transfer pump 28 is activated by this change command signal, and the elastic substance 13 is injected from the elastic substance holding tank 27 into the double pipe consisting of the small diameter pipe 2 and the outer pipe 26.

In accordance with the weight of the elastic substance 13 injected into the double pipe, the weight of the outer pipe 26 portion of the small diameter pipe 2 changes, and the natural frequency of the small diameter pipe 2 changes. Resonance phenomenon in is suppressed. The weight of the elastic substance 13 in the double pipe in accordance with the change command signal can be easily increased or decreased by the injection amount of the elastic substance 13 by the operation of the transfer pump 28 or the discharge amount of the elastic substance 13 by the discharge valve 30. .

Further, the elastic substance 13 in the spring constant changing device 11 of the vibration reducing device 10, the elastic substance 13 in the vibration reducing device 25, the driving device 20 of the vibration reducing device 16 and the buffer material (not shown) in the supporting device 24. For example, oil, water, springs, etc. are adopted. As a result, the elasticity possessed by the elastic material 13 does not restrain the gradual heat transfer due to thermal expansion or the like in the small-diameter pipe 2, but it restrains the shocking load generated by an earthquake or the like. Vibration can be reduced.

Further, the database unit 8 stores data such as the optimum natural frequency which suppresses the resonance of the small diameter pipe 2 due to the diagnosis of the diagnosis device 7, which is the operation result of the present piping system vibration reducing device.

By creating a database of information such as the optimum natural frequency in the database unit 8, the database unit 8 immediately sends data to the diagnostic device 7 even when a new fluctuating frequency load is applied to the small diameter pipe 2. I will provide a.
The diagnostic device 7 outputs a change command signal of the natural frequency based on the optimum natural frequency for suppressing the resonance with respect to the fluctuating frequency load to each vibration reduction device, and the vibration due to the resonance generated in the small diameter pipe 2 is generated. Can be immediately suppressed.

[0046]

As described above, according to the present invention, the resonance vibration generated in the small-diameter small-diameter pipe connected to the large-diameter mother pipe is easily suppressed. It is possible to prevent the leakage of the contained fluid due to this, and thus it is possible to improve the reliability and maintainability of the piping system in various plants.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a piping system vibration reduction device according to an embodiment of the present invention.

FIG. 2 is a partially cut configuration diagram of the first embodiment according to the vibration reducing device of the present invention.

FIG. 3 is a perspective configuration diagram of a second embodiment according to the vibration reducing device of the present invention.

FIG. 4 is a front configuration diagram of a third embodiment according to the vibration reducing device of the present invention.

5A and 5B are cross-sectional structural views of a fourth embodiment of the vibration reduction device of the present invention, in which FIG. 5A is an overall view and FIG. 5B is A- in FIG. 5A.
FIG.

[Explanation of symbols]

1 ... Mother pipe, 2 ... Small diameter pipe, 2a, 22a ... Rail, 3 ... Mother pipe vibration measuring device, 4 ... Small diameter pipe vibration measuring device, 5a, 5
b, 10, 16, 21, 25 ... Vibration reduction device, 6 ... Analysis device, 7
... Diagnostic device, 8 ... Database unit, 9, 24 ... Support device,
11 ... Spring constant changing device, 12, 20, 23 ... Drive device, 13 ... Elastic material, 14 ... Cylinder, 15 ... Piston, 17 ... Support base, 18
... wire, 19 ... drive mechanism, 22 ... variable support device, 26 ... outer tube, 27 ... elastic substance holding tank, 28 ... transfer pump, 29 ... piping, 30 ... discharge valve.

Claims (8)

[Claims] 1. A pipe system comprising a large-diameter mother pipe and a small-diameter pipe having a smaller diameter than the mother pipe connected to the mother pipe, and the mother-pipe vibration measuring device for the mother pipe and the small-diameter pipe vibration measuring device for the small-diameter pipe. In addition to installing an analyzer, an analysis device that analyzes the measurement data obtained by both vibration measurement devices, a diagnosis device that diagnoses resonance based on the analysis result, and the natural frequency of the small diameter pipe based on the diagnosis data. A vibration reducing device for a piping system, which is provided with a vibration reducing device for changing the vibration. 2. The vibration reducing device for a piping system according to claim 1, wherein the vibration reducing device for changing the natural frequency provided in the small diameter pipe is a supporting device for varying a spring constant in supporting the pipe. . 3. The piping system vibration reduction according to claim 1, wherein the vibration reducing device provided on the small diameter pipe for changing the natural frequency is a supporting device for varying the pipe fixing force of the pipe support. apparatus. 4. The vibration reducing device for a piping system according to claim 1, wherein the vibration reducing device for changing the natural frequency provided in the small diameter pipe is a variable supporting device for changing the pipe supporting position. 5. A vibration reducing device for changing the natural frequency provided in the small diameter pipe, wherein the outer diameter of the small diameter pipe is doubled and the partial weight of the small diameter pipe is made variable by the amount of the substance injected into the inside. The piping system vibration reducing device according to claim 1. 6. The piping system vibration reduction device according to claim 1, wherein the substance used in the vibration reduction device is an elastic substance that absorbs heat transfer of the pipe due to vibration and thermal expansion during an earthquake. 7. The analysis device evaluates the soundness of the small diameter pipe by calculating the stress of the small diameter pipe by using the measurement data obtained from the mother pipe vibration measuring device as an input load to the small diameter pipe. The piping system vibration reduction device according to claim 1. 8. An optimum characteristic for preventing resonance in a small-diameter pipe obtained from an analysis device and a diagnostic device from measurement data of a mother pipe vibration measuring device and a small-diameter pipe vibration measuring device when vibration of a certain frequency occurs in the small-diameter pipe. The piping system vibration reduction according to claim 1, further comprising: a database unit for storing the frequency data and providing the stored optimum natural frequency data to the diagnostic device when the vibration of the frequency occurs again. apparatus.