JP2004092860A - Fluid piping structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid piping structure without needs for cutting off water supply or stopping a function during a piping cut operation and a piping recovery operation at the time of sampling research. <P>SOLUTION: This fluid piping structure comprises fluid piping 1 installed in a building and transferring fluids; monitoring piping 2 detachably installed at an intermediate part of the fluid piping 1; a flow-in switch valve V1 installed to the fluid piping 1 on a primary side of the monitoring piping 2; a flow-out switch valve V2 installed to the fluid piping 1 on a secondary side of the monitoring piping 2; and a bypass pipe 3 branched from the fluid piping 1 on the primary side of the flow-in switch valve V1 and combined with the fluid piping 1 on the secondary side of the flow-out switch valve V2. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid piping structure applied as equipment piping in a building or plant piping in a factory or the like.
[0002]
[Prior art]
In equipment piping in a building or plant piping in a factory or the like, the piping gradually deteriorates from the start of use of the piping system after the completion of the piping work, and finally the fluid in the piping leaks to the outside. Deterioration of pipes begins to corrode from the inner surface of the pipes, and the corrosion progresses gradually, so that the wall thickness of the pipes decreases. Therefore, it is necessary to carry out pipe renewal work before the pipe stops functioning.However, it is difficult to determine the corrosion state of the pipe's inner surface only by visual inspection from the outer surface of the pipe. It is the present condition that the update time is determined.
[0003]
Until now, the deterioration of pipes has been diagnosed by picking up and examining several important points from the relevant equipment piping for some of the following survey items, and comprehensively judging from the results of those surveys. ing.
(1) A part of the existing piping is cut and sampled, and the sample is split (vertically divided) and visually inspected.
(2) Use an ultrasonic thickness gauge to measure and survey the pipe thickness.
(3) Install an ultrasonic flowmeter on the outer surface of the piping and measure and measure the flow rate in the piping.
(4) Using an X-ray equipment, take an X-ray photograph of the piping and investigate.
(5) Insert the fiberscope into the piping and visually inspect the condition of the inner surface of the piping.
[0004]
In the above, in the case of piping X-ray survey, there is an advantage that it is not necessary to shut down the water of the surveyed system or stop functioning, but a large space is required for installing X-ray equipment, and the cost required for the survey is other. It is rarely adopted because of disadvantages such as high cost compared to the survey in Japan.
[0005]
In addition, when an actual measurement survey of the pipe wall thickness is performed using an ultrasonic thickness gauge, it is necessary to take a small number of measurement points per location in order to grasp the corrosion state in the pipe using only this survey. (The number of measurement points in the inner circumferential direction of the pipe x the number of measurement points in the pipe axis direction). For this reason, in order to determine whether or not to conduct a full-scale survey such as piping sampling, a sub-survey such as actually measuring several points of the pipe thickness is often performed.
[0006]
When a building is newly constructed, it is not generally practiced to incorporate a diagnosable piping unit or piece into the piping in order to check the future deterioration status of the facility piping and make a facility piping renewal plan.
As a very few examples, a short flange of about 300 mm may be attached to the piping in the machine room as a sampling piece, but it is only possible to grasp the deterioration of the piping in the entire piping system by sampling survey of the piping in the machine room. The reality is that it is difficult and not really useful.
[0007]
The above prior art is a technique generally known to those skilled in the art, and does not relate to the invention disclosed in the literature.
[0008]
[Problems to be solved by the invention]
The conventional fluid piping structure has a problem in that when sampling the piping for deterioration diagnosis, the piping system after the sampling portion must be once disconnected during the piping cutting operation and the piping restoration operation. In particular, in the case of a central circulation hot water supply piping system such as a hot water supply facility near a supply pump such as a water supply facility, or a hot / cold water circulation piping system such as an air conditioner, there is a problem that all functions of the system must be stopped during work. there were.
[0009]
In general, if there is a curved pipe portion or a valve in the pipe, the fluid in the pipe around the pipe portion becomes turbulent. When the ultrasonic flowmeter measures in a portion where the fluid in the pipe is in a turbulent state, a large error occurs in the measured value or the measurement becomes impossible at worst. For this reason, it is said that the pipe needs a considerably long straight pipe section (generally, the pipe inner diameter x 15 times) for measurement. However, there are few such long straight pipe sections in the pipes of existing buildings, especially in the horizontal branch pipe system on each floor. Furthermore, the location where the ultrasonic flowmeter can be installed is further limited, and at the worst, there is a problem that the ceiling must be peeled off or the wall must be broken before installation.
[0010]
In the investigation using a fiberscope, if the toe of the valve, the toe of the cap, the pressure gauge mounting part, etc. are located around the part to be investigated, a fiberscope is inserted therefrom for the investigation. However, in actual surveys, there are few places around the periphery where convenient insertion is possible. When a pipe is cut at the time of the pipe sampling survey described above, a fiber scope is often inserted from the end to conduct the survey. In this case, both the pipe sampling survey and the fiber scope survey are performed, and there has been a problem that the time required to cut off the water or stop the function of the piping system is further increased.
[0011]
The present invention has been made in order to solve the above-described problems, and it is not necessary to cut off or stop the piping system to be inspected during piping sampling work and pipe restoration work during piping sampling survey. It is an object to provide a fluid piping structure.
[0012]
It is another object of the present invention to provide a fluid piping structure that can reliably measure the flow rate of a fluid in a pipe using an ultrasonic flow meter and can obtain an accurate flow rate measurement value.
[0013]
Still another object of the present invention is to provide a fluid pipe structure that can shorten the insertion distance of the fiber scope to a point where the deterioration state is inspected in the pipe, and can easily perform the insertion. .
[0014]
[Means for Solving the Problems]
A fluid pipe structure according to the present invention includes a fluid pipe disposed in a building for transporting a fluid, a monitor pipe detachably provided at an intermediate portion of the fluid pipe, and a monitor pipe primary side. An inflow opening / closing valve arranged in the fluid piping, an outflow opening / closing valve arranged in the fluid piping on the secondary side of the monitor pipe, and a branch from the fluid piping on the inflow opening / closing valve primary side, and And a bypass pipe that joins the fluid pipe on the secondary side of the on-off valve.
[0015]
A bypass pipe inflow opening / closing valve and a bypass pipe outflow opening / closing valve are arranged in a bypass pipe of a fluid piping structure according to the present invention.
[0016]
A fluid pipe structure according to the present invention includes a fluid pipe disposed in a building for transporting a fluid, a monitor pipe detachably provided at an intermediate portion of the fluid pipe, and a monitor pipe primary side. An inflow-side three-way switching valve disposed in the fluid pipe, an outflow-side three-way switching valve disposed in the fluid pipe on the secondary side of the monitoring pipe, and a branch from the inflow-side three-way switching valve, And a bypass pipe merging with the side three-way switching valve.
[0017]
The monitor pipe of the fluid pipe structure according to the present invention is made of the same material as the fluid pipe.
[0018]
The monitoring pipe of the fluid piping structure according to the present invention has a straight pipe portion having a length of 15 times or more the inner diameter of the pipe.
[0019]
The monitoring pipe of the fluid piping structure according to the present invention has a branch outlet on the outer peripheral surface of the pipe, and an on-off valve is connected to the branch outlet.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described.
Embodiment 1 FIG.
FIG. 1 is a schematic diagram showing a fluid piping structure according to Embodiment 1 of the present invention.
In FIG. 1, reference numeral 1 denotes a fluid pipe disposed in a building for transporting a fluid, and the fluid pipe 1 is separated at a degradation state investigation target (monitor) site, and 1A is its primary side (upstream side). Fluid piping and 1B respectively show a secondary (downstream) fluid piping.
[0021]
V1 is an inflow-side on-off valve provided in the primary-side fluid pipe 1A, V2 is an outflow-side on-off valve provided in the secondary-side fluid pipe 1B, and 2 is a connection between the primary-side fluid pipe 1A and the secondary-side fluid pipe 1B. It is a detachable monitor pipe that can be removed. Therefore, the monitor pipe 2 is detachably provided in the middle of the fluid pipe 1, and the branch outlets (branch outlet pipes) 2a and 2b are provided upstream and downstream of the monitor pipe 2. Are provided, and on-off valves V3, V4 are connected to the branch outlets 2a, 2b. Here, the monitor pipe 2 is made of the same material as the fluid pipe 1.
[0022]
Reference numeral 3 denotes a bypass pipe connecting the primary side of the inflow-side on-off valve V1 in the primary fluid pipe 1A and the secondary side of the outflow-side on-off valve V2 in the secondary fluid pipe 1B. An on-off valve V5, an outflow-side on-off valve V6, and a drain valve V7 located on the inflow side of the outflow-side on-off valve V6 are provided.
[0023]
Next, the operation will be described.
In normal use of the above-described fluid piping structure, the inflow-side on-off valve V1 and the outflow-side on-off valve V2 of the fluid piping 1 are opened, while the on-off valves V3, V4 and the bypass pipe 3 of the monitoring piping 2 are opened. Of the inflow-side on-off valve V5 and the outflow-side on-off valve V6 are closed. Thus, during normal use, water does not flow into the bypass pipe 3. If water enters the bypass pipe 3 due to an erroneous operation or the like, the drain valve V7 may be opened to drain water.
[0024]
If the device is used for a long period of time in the above situation, water flows from the primary fluid pipe 1A to the monitor pipe 2 and the secondary fluid pipe 1B, so that the inner surfaces of the fluid pipe 1 and the monitor pipe 2 are corroded. It gradually deteriorates.
[0025]
Therefore, in order to investigate the deterioration state of the pipe, first, sampling of the pipe is performed. In this case, the following operation is performed.
(1) The inflow-side on-off valve V5 and the outflow-side on-off valve V6 of the bypass pipe 3 are opened.
{Circle around (2)} The inflow-side on-off valve V1 and the outflow-side on-off valve V2 of the fluid pipe 1 are closed.
(3) Open the on-off valves V3 and V4 of the monitor pipe 2 and pull out the water in the pipe between the inflow-side on-off valve V1 and the outflow-side on-off valve V2, or take care with the pan, etc. Remove the pipe 2.
(4) A pipe equivalent to the monitor pipe 2 is mounted between the primary fluid pipe 1A and the secondary fluid pipe 1B from which the monitor pipe 2 has been removed, and the pipe is restored.
(5) After the restoration of the piping, the inflow-side on-off valve V1 and the outflow-side on-off valve V2 of the fluid piping 1 are opened.
(6) Close the inflow-side on-off valve V5 and the outflow-side on-off valve V6 of the bypass pipe 3.
(7) The drain valve V7 is opened to drain the water in the bypass pipe 3.
[0026]
According to the first embodiment described above, at the time of piping sampling, the inflow-side on-off valve V1 and the outflow-side on-off valve V2 of the fluid pipe 1 are closed, and the inflow-side on-off valve V5 and the outflow-side on-off valve V6 of the bypass pipe 3 are closed. By opening the monitor pipe, it is possible to remove the monitor pipe 2 and to use it for investigating the deterioration state without interrupting the water supply or stopping the function of the equipment pipe.
[0027]
Embodiment 2 FIG.
FIG. 2 is a schematic diagram showing a fluid piping structure according to Embodiment 2 of the present invention. The same components as those in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted.
In the second embodiment, an inflow-side three-way switching valve V8 is provided in the primary fluid pipe 1A, and an outflow-side three-way switching valve V9 is provided in the secondary fluid pipe 1B, and these three-way switching valves V8 and V9 are provided. The bypass pipe 3 is connected to a primary fluid pipe 1A and a secondary fluid pipe 1B.
[0028]
According to the second embodiment having such a configuration, by simply switching the two positions of the inflow-side three-way switching valve V8 and the outflow-side three-way switching valve V9 of the fluid piping 1, the equipment piping is cut off or the function is stopped. The monitor pipe 2 can be removed without any trouble, and the pipe can be easily restored after the removal. Further, the number of valves to be used can be reduced by half as compared with the case of the above-described first embodiment, so that piping sampling work can be performed more easily and cost can be reduced.
[0029]
FIG. 3 is an external view showing a monitor pipe in FIGS. 1 and 2.
In the same figure, 2A is a straight pipe portion of the monitor pipe 2, 2B and 2C are curved pipe portions at both ends of the monitor pipe 2, L is the length of the straight pipe section 2A, and L is the length of the straight pipe section 2A. The length L is set to about 15 times (L ≧ 15d) the inner diameter d of the monitor pipe 2.
[0030]
Reference numeral 10 denotes a sensor section of the ultrasonic flowmeter installed on the outer surface of the straight pipe section 2A of the monitor pipe 2. The installation position of the sensor unit 10 is set at a position where the flow of the fluid in the monitor pipe 2 is in a laminar flow state, and from the upstream end of the straight pipe part 2A of the monitor pipe 2 toward the downstream side. It is desirable that the straight pipe section 2A be located at an installation position of L1 ≧ 10d and have a distance L2 ≧ 5d from the installation position to the downstream side of the straight pipe section 2A.
[0031]
Here, if the length L of the straight pipe portion 2A of the monitoring pipe 2 in which the sensor section 10 of the ultrasonic flowmeter is installed on the outer surface is L <15d, the fluid in the pipe will be curved pipe section 2B of the monitoring pipe 2, In a turbulent state affected by the 2C and the valve, the sensor reaches the installation position of the sensor unit 10 in a turbulent state, so that the flow rate cannot be measured or an accurate flow rate measurement value cannot be obtained. On the other hand, in the present invention, as described above, the length L of the straight pipe portion 2A of the monitoring pipe 2 is set to L ≧ 15d, and L1 is set from the upstream end of the straight pipe portion 2A to the downstream side. The installation position of the sensor unit 10 is set at a position of ≧ 10d, and the distance from the installation position to the downstream end of the straight pipe unit 2A is set so as to satisfy L2 ≧ 5d. The sensor unit 10 is not affected by the turbulence of the fluid in the pipe generated by the influence of the valves 2B and 2C and the valve. For this reason, an accurate flow rate measurement value by the ultrasonic flow meter can be obtained.
[0032]
Note that the straight pipe portion 2A of the monitor pipe 2 may be any length as long as it is within the above-described conditions of L, L1, and L2, but since there is no difference in measurement accuracy, from the economic viewpoint, L = Most preferably, 15d, L1 = 10d, and L2 = 5d. Most preferably, the monitoring pipe 2 is a straight pipe having no curved pipe sections 2B and 2C.
[0033]
The ultrasonic flow meter 10 measures the flow velocity in the pipe, and calculates the flow rate of the pipe by multiplying the flow velocity by a cross section. That is, since the measurement error increases as the pipe diameter increases, the installation position should satisfy the above conditions as the pipe diameter of the piping system to be measured increases.
In the current measurement technology, the above conditions are optimal for the installation of the flowmeter sensor. However, in the future, the accuracy of the ultrasonic flowmeter will be improved, and accurate flow measurement will be possible even in a straight pipe shorter than the above conditions. This is not the case when a value can be obtained.
[0034]
When investigating the state of deterioration in the piping using a fiber scope, first, the piping system in the inspection range is cut off, and water in the piping is drained from the on-off valves V3, V4, etc. of the monitoring piping 2. After the drainage operation is completed, a fiberscope is inserted into the fluid pipe from the on-off valves V3 and V4 via the branch outlets 2a and 2b, and a visual inspection is performed.
[0035]
In addition, at the time of normal use, if a pressure gauge or the like is installed in the on-off valves V3, V4 of the branch outlets 2a, 2b, the pressure in the piping can be visually checked during normal maintenance.
[0036]
Further, when the fiberscope is inserted into the fluid pipe, a structure in which the interior of the on-off valves V3 and V4 and the fiberscope are sealed in a liquid-tight manner with a rubber-based or silicon-based packing or the like can be used. is there. In this case, there is no need to cut off or drain the water of the piping system to be investigated, so that a more effective investigation can be performed.
[0037]
In each of the embodiments described above, the branch outlets 2a and 2b are provided at two places in the monitoring pipe 2, but the branch outlets play a sufficient role even if only one place.
[0038]
Further, if the pipe diameter of the monitor pipe 2 and the bypass pipe 3 are made the same, even if the monitor pipe 2 is removed and the bypass pipe 3 is continuously used without restoring the pipe at the removed portion, There is no fear of adversely affecting the equipment of the piping system (for example, even if there is a change in pipe pressure, pipe flow velocity, etc., it is very small and there is no problem), so that it is more effective.
[0039]
In each of the above embodiments, the monitor pipe 2 and the fluid pipe 1 may be connected to each other by a detachable connection structure such as a flange connection, a mechanical connection, and a housing connection. You may.
[0040]
【The invention's effect】
As described above, according to the present invention, since each of the bypass pipe and the fluid pipe has the inflow-side on-off valve and the outflow-side on-off valve, during the pipe cutting work and the pipe restoration work when performing the pipe sampling investigation, There is no need to cut off the water of the target piping system, especially in the vicinity of the supply pumps such as water supply facilities, central circulating hot water supply piping systems such as hot water supply facilities, and cold / hot water circulation piping systems such as air conditioners, etc. There is an effect that the pipe sampling work can be performed without any need.
[0041]
According to the present invention, since the straight pipe portion of the monitor pipe has a length of 15 times or more the inner diameter of the pipe, the flow rate of the fluid in the pipe can be reliably measured by installing the ultrasonic flowmeter. There is an effect that an accurate measurement value can be obtained.
[0042]
According to the present invention, since the fiber scope can be inserted from the on-off valve provided at the branch outlet of the monitor pipe, the fiber scope can be inserted endlessly from the remote pipe outlet or the like to the inspection point in the pipe, or the pipe can be inserted. There is an effect that there is no need to cut the fiberscope and insert a fiberscope.
[0043]
According to the present invention, when the inside of the on-off valve and the cable of the fiber scope are liquid-tightly sealed with packing or the like and the fiber scope is inserted into the pipe, the piping system to be investigated is cut off or drained. There is no need to do this.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a fluid piping structure according to a first embodiment of the present invention.
FIG. 2 is a schematic diagram showing a fluid piping structure according to a second embodiment of the present invention.
FIG. 3 is an external view showing a monitor pipe in FIGS. 1 and 2;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fluid piping 1A Primary fluid piping 1B Secondary fluid piping 2 Monitoring piping 2a, 2b Branch extraction part 2A Straight pipe part 2B, 2C Curved pipe part 3 Bypass pipe V1, V2, V3, V4, V5, V6 On-off valve V7 Drain valve V8, V9 Three-way switching valve 10 Sensor part of ultrasonic flow meter

Claims (6)

A fluid pipe disposed in the building for conveying fluid, a monitor pipe detachably disposed at an intermediate portion of the fluid pipe, and an inflow disposed in the fluid pipe on the primary side of the monitor pipe. An on-off valve, an outflow on-off valve disposed on the fluid pipe on the secondary side of the monitor pipe, and the fluid pipe on a secondary side of the outflow on-off valve branched from the fluid pipe on the primary side of the inflow on-off valve And a bypass pipe that merges with the fluid pipe structure. The fluid piping structure according to claim 1, wherein the bypass pipe is provided with a bypass pipe inflow opening / closing valve and a bypass pipe outflow opening / closing valve. A fluid pipe disposed in the building for conveying fluid, a monitor pipe detachably disposed at an intermediate portion of the fluid pipe, and an inflow disposed in the fluid pipe on the primary side of the monitor pipe. Side three-way switching valve, an outflow-side three-way switching valve disposed on the fluid pipe on the secondary side of the monitor pipe, and a bypass pipe branched from the inflow-side three-way switching valve and merging with the outflow-side three-way switching valve A fluid piping structure comprising: The fluid pipe structure according to any one of claims 1 to 3, wherein the monitor pipe is made of the same material as the fluid pipe. The fluid piping structure according to any one of claims 1 to 4, wherein the monitoring pipe has a straight pipe portion having a length of at least 15 times the inner diameter of the pipe. The monitoring pipe according to any one of claims 1 to 5, wherein the monitoring pipe has a branch outlet on an outer peripheral surface of the pipe, and an on-off valve is connected to the branch outlet. Fluid piping structure.

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