JPH06201534A - Device and method for detecting blocked position inside pipe and method for controlling amount of unloaded oil - Google Patents

Abstract

PURPOSE:To provide a device and method for detecting the blocked position inside a pipe of unloaded mud and earth/sand which can detect the blocked position easily from the outside of the pipe without requiring any experience. CONSTITUTION:An ultrasonic transmitter 29 and an ultrasonic receiver 31 of Doppler-type ultrasonic flowmeter 1 are molded into one transducer 17. Since the transducer is provided at the outer periphery of a pipe P. it can be mounted easily and even an inexperienced operator can detect the blockage inside the pipe easily. Also, a plurality of ultrasonic flowmeters 1 which are provided at the outer periphery of a specific position along the pipe P measures the flow rate of earth/sand etc., at the position inside each section of each point. A control part judges the blocked position inside the pipe based on the signal from the ultrasonic receiver 31, thus detecting the blockage inside the pipe positively even if the number of the ultrasonic flowmeters 1 which are provided as the extension of the pipe P increases.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting a closed position in a pipe, a method for detecting the position, and a method for managing the amount of discharged soil using this detection device. The present invention relates to an in-pipe blockage position detection device and a detection method for detecting the in-pipe blockage position from the outside of the pipe, and a discharged soil volume management method using this detection device.

[0002]

2. Description of the Related Art In tunnel construction in the suburbs of cities, recently, the mud pressure pumping method has become the mainstream rather than the mud shield method because of the shortage of land processing facilities. According to this mud pressure feeding method, the situation varies depending on the pressure feeding distance, etc.
Due to the following reasons, sediment deposits may adhere to the pipe of the discharged mud and cause blockage in the pipe, which may cause a delay in work.

(1) Viscosity of sludge and insufficient flow velocity.

(2) Mud materials do not mix well with the ground inside the shield machine.

(3) Since the backfill component is a strong alkali, its viscosity is lowered. In particular, backfill injection enters the chamber because overcutting is performed in the curved section.

(4) If the ground of the cutting face becomes clay and fine sand, the mud material will not mix.

(5) When the amount of WAP used is increased, water is absorbed and the flow effect is lost.

(6) When the soil of the face is gravel and sandy,
Gravel will settle in the pipe.

(7) Bacteria in water for making mud materials
When bacteria occur, the viscosity decreases due to bacteria.

(8) When the clay layer is formed, clay easily adheres to the inside of the pipe, and the resistance inside the pipe increases.

(9) If the extension distance of the shield excavation becomes long, the mud making pipe will become long even if the viscosity of mud is changed with respect to the soil quality of the natural ground, and it will take a long time to reach the chamber. Become slow.

(10) The mud-making material does not mix even if agitated in the chamber due to the excess moat in the curved section.

When such a blockage in the pipe occurs, an experienced worker hits the pipe with a hammer and detects it by a subtle difference in the sound, and finds a bent portion or a reduced portion of the pipe to determine the closed position. Is generally detected.

[0014]

However, in such a conventional technique, it takes a long time to detect the closed position if there is no skilled person because it requires skill of the operator. It is difficult to get results. Therefore, there is a risk that the subsequent measures will be delayed and the construction schedule will be delayed.

Therefore, a pressure sensor is provided in the pipe in order to detect the closed position in the pipe uniformly even if it is not an expert.
It is possible to judge whether or not the inside of the tube is blocked by this change in pressure. However, in this case, the pressure sensor projects into the pipe in order to directly measure the pressure of the muddy water in the pipe, and this pressure sensor may cause a blockage in the pipe.

The object of the present invention has been made in view of such a conventional technique, and requires no skill and can detect a closed position inside a pipe which can easily detect the closed position from the outside of the pipe. ， It is to provide a detection method and a discharged soil quantity management method.

[0017]

In order to achieve the above-mentioned object, a device for detecting a closed position in a pipe according to the present invention integrally includes an ultrasonic transmitter and an ultrasonic receiver of a Doppler type ultrasonic flowmeter. The transducer is provided on the outer circumference of the tube. Here, it is desirable to provide a plurality of transducers on the outer periphery of a predetermined position along the tube and to provide a control device for determining occlusion based on a signal from the ultrasonic receiver.

Further, the method for detecting the closed position in the pipe is to detect the closed pipe when the Doppler ultrasonic flowmeter provided on the outer circumference of the pipe detects zero flow velocity at a predetermined position in the cross section of the pipe.

Further, according to the discharged soil quantity management method, when the blockage in the pipe is detected based on the signals from the ultrasonic flowmeters provided at the outer periphery of the predetermined position along the pipe, the control device automatically injects the lubricant. Is to command.

[0020]

According to the in-pipe closed position detecting device of the present invention, the ultrasonic transmitter and the ultrasonic receiver of the Doppler ultrasonic flowmeter are integrated into one transducer, and this transducer is provided on the outer circumference of the pipe. It can be easily attached, and even an unskilled person can easily detect the blockage in the tube.

Further, a plurality of ultrasonic flowmeters provided on the outer periphery of a predetermined position along the pipe measure the flow rate of earth and sand etc. at each position in each cross section, and based on the signal from this ultrasonic receiver. Since the control device determines the pipe blocking position,
Even if the number of ultrasonic flowmeters provided by increasing the length of the tube is increased, the blockage in the tube can be reliably detected.

Further, according to the pipe closing position detecting method and the discharged soil amount managing method according to the present invention, it is determined that the pipe closing will eventually occur when the flow rate at the predetermined position in the pipe cross section becomes zero, so that the control device Lubricant injection can be commanded to prevent tube obstruction.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to the drawings.

FIG. 7 shows the entire tunnel excavation work using the Doppler type ultrasonic flowmeter 1 as a pipe closing position detecting device for discharged mud and sand according to the present invention.

In FIG. 7, at the forefront (the left end of FIG. 7),
There is a shield excavator 3, which moves forward while excavating the natural ground. A primary screw conveyor 5 and a secondary screw conveyor 7 are connected behind the shield excavator 3, and a primary earth and sand pressure pump 9 and a hydraulic unit 11 are provided behind it. A pipe P for pumping sediment generated during excavation is connected to the primary sediment pump 9. A telescopic device 13 is provided in the middle of the pipe P.
Is provided so that the pipe P extends as the excavation proceeds.

The pipe P is connected to the secondary sediment pressure pump 15 and conveys the sediment to the secondary sediment pressure pump 15.
A pipe P is further connected to the secondary sediment pump 15 to newly pressurize and discharge the sediment to the ground.

A Doppler type ultrasonic flowmeter 1 is attached at a predetermined position outside the pipe P. The Doppler type ultrasonic flowmeter 1 is provided, for example, at equal intervals,
Alternatively, it is desirable that the pipes be arranged more densely since they are likely to be clogged in the pipe at a place away from the earth and sand pumps 9 and 15.

The transducer 17 of the ultrasonic flowmeter 1 is mounted at a predetermined position outside the pipe P, as shown in FIG. Further, referring also to FIG. 5, the ultrasonic flowmeter 1 is connected to the integration indicator 21, the integration recorder 23, etc. of the control device 19, and the primary sediment pressure pump 9 and the secondary sediment pressure pump 15 are connected. It is connected to a control unit 27 for controlling a mud making pump and a mud making valve 25 for injecting a mud making material as a lubricant into the control unit 27, and transmits the measured result to the control unit 27.

Here, the Doppler type ultrasonic flowmeter 1 will be described with reference to FIGS. 1 and 2. First, the ultrasonic Doppler effect applied by the Doppler ultrasonic flowmeter 1 generally has the following relationship, where λ is the wavelength, f is the frequency (or frequency), and C is the propagation velocity of the sound wave. That is, the relationship of C = λ · f or λ = C / f is established.

(1) The vibration source is fixed, and the measurer
When approaching the vibration source at the speed of, the frequency fk reaching the measurer is given by the following equation.

[0031]

Fk = f + fd = f + V / λ = f + V / (C / f) = fx (1 + V / C) Further, when the vibration source is fixed and the measurer moves away from the vibration source at the speed of V, The frequency fk reaching the measurer is given by the following equation.

It is given by fk = f × (1-V / C).

Therefore, when the vibration source is fixed and the measurer moves at a speed of ± V, the frequency of the sound reaching the measurer is fk.
= Fx (1 ± V / C).

(2) With the measurer stopped, the vibration source is V
Frequency f reaching the measurer when approaching the measurer at the speed of
m is given by the following equation.

Fm = f × C / (C-V) When the vibration source moves away from the measurer at a velocity of V while the measurer is stopped, the frequency fm reaching the measurer is given by the following equation. To be

Fm = f × C / (C + V) Therefore, the frequency that reaches the measurer when the vibration source moves at a speed of ± V is given by fm = f × C / (C ± V).

There are a single head type and a dwell head type as the transducers of the Doppler flowmeter. The single head type shown in FIGS. 1 and 2 will be described. Single head transducer 17
In the tube P, a transmitter 29 that emits an ultrasonic wave and a receiver 31 that receives the reflected ultrasonic wave are integrally molded.

Oscillation frequency (f ₁ ) due to Doppler effect
And the reception frequency (f ₂ ) are measured, the moving speed of the sand in the pipe P is calculated as follows.

Δf = | f ₁ −f ₂ | = f ₀ × (C + Vcos θ) / (C−Vcos θ) −f ₀ = f ₀ × 2 Vcos θ / (C−Vcos θ) Is much faster than the measured flow velocity, so that C> Vcos θ, and Δf = f ₀ × 2Vcos θ / C. Therefore, V = (C / 2f ₀ cos θ) × Δf. From this, if f ₀ and C / cos θ are constant, V = KΔ
f.

That is, it can be seen that the difference between the transmission frequency and the reception frequency due to the reflection of ultrasonic waves is proportional to the flow velocity. The Doppler type ultrasonic flowmeter 1 measures the flow velocity in the pipe P from the outside by utilizing this property.

FIG. 3 shows the flow velocity of the earth and sand inside the pipe P measured using the Doppler type ultrasonic flowmeter 1 described above. The flow velocity shown in FIG. 3 is calculated by the control unit 27 according to the above equation V = KΔf. Referring also to FIG. 4, the transducer 17 is attached to five points A to E in one cross section of the pipe P, and the flow velocity of the inside portion of each point (hatched portion in the figure), that is, the amount of the discharged mud and sand. The state of precipitation is being measured.

The first measurement result shown in FIG. 3 is obtained by setting a measurement point along the pipe P at a predetermined position (between the primary sediment transport pump 9 and the secondary sediment transport pump 15). is there. And the measurement result of the 2nd time has shown the result performed when digging 61m after that. Therefore, the second measurement point is located at a position 61 m away from the first sediment pressure pump 9 than the first measurement point.
The unit of the first and second data is cm / sec.

From the results shown in FIG. 3, it is shown that the sediment flows to the measurement points A to E at a position near the sediment pump 9, and sedimentation is not observed at all. Then, as the distance from the sediment pump 9 increases, the pipe P
On the lower side (closer to the point E in the figure), the flow velocity is zero, indicating that no sediment is flowing. That is, it can be determined that the sediment has already settled near the point where the flow velocity is zero. This tendency indicates that as the digging progresses, it is settled from the lower side of the pipe P at a point far from the shield excavator 3.

If the position (eg, point B, point C, point D, etc.) for determining the blockage in the tube is determined according to the distance from the tube P, the ultrasonic flow rate provided outside the tube P is determined. 1 in total
It is possible to judge if one is provided.

Next, the discharged soil amount management system for managing the discharged soil amount using the Doppler type ultrasonic flowmeter 1 described above will be described with reference to FIG.

As described above, when the flow velocity measured by the ultrasonic flowmeter 1 attached to the predetermined position of the pipe P extending from the shield excavator 3 to the ground is transmitted to the control unit 27, the control unit 27 For example, 27 can detect the position where the pipe P is closed by determining that the pipe P is in the closed state near the cross section when the flow velocity becomes zero up to the points E, D and C and the sediment is settled. . Based on this result, the control unit 27 controls the mud making pump and the mud making valve 25 to perform mud making injection in a pump (not shown) to prevent clogging in the pipe. Then, the ultrasonic flow meter 1 is continuously used to measure the flow velocity again, and the monitoring is continued so as not to cause blockage in the tube.

As described above, when the Doppler type ultrasonic flowmeter 1 is used, it can be easily attached to any position because it is attached to the outside of the pipe P. And the pipe P
Since it is possible to detect the state of the flow of earth and sand inside the pipe P from the outside of the pipe, it is possible to easily predict the blockage point in the pipe without causing pressure loss, and by connecting with the control unit 27 to control the mud injection. Intraluminal obstruction can be prevented. As a result, the efficiency of excavation work can be improved.

The present invention is not limited to the above-mentioned embodiment, but can be carried out by appropriately changing it. That is, in the above embodiment, the case where the primary and secondary earth and sand pressure pumps 9 and 15 are provided has been described, but even if the extension of the pipe P is increased and the number of pumps is increased, the same application is possible. .

In the above embodiment, the case of measuring the flow rate of the earth and sand flowing inside the pipe P has been described.
In addition to this, chemical liquid injection, high-viscosity materials, solid materials and fluids, etc., pumping equipment, pipeline management in sewage treatment plants, concrete placement piping, blockage management of backfill injection, blockage management in curved piping, shield pipe It can be widely applied to pumping management, pipe transportation management in pharmaceutical factories, etc.

[0049]

The pipe closing position detecting device and detecting method for discharged mud and sand according to the present invention, and the discharged amount management method using this detecting device have the above-described structure, and the Doppler ultrasonic flow rate is used. The ultrasonic transmitter and ultrasonic receiver of the meter are molded into a single transducer, and this transducer is provided on the outer circumference of the pipe, so it can be easily installed, and even an unskilled person can easily detect the blockage in the pipe. can do.

Further, a plurality of ultrasonic flowmeters provided on the outer periphery of a predetermined position along the pipe measure the flow rate of the sediment or the like at the position in each section at each point, and based on the signal from the ultrasonic receiver. Since the control device determines the position of the blockage in the pipe, the blockage in the pipe can be reliably detected even if the length of the pipe is increased and the number of ultrasonic flowmeters arranged increases.

Further, when the flow velocity at a predetermined position in the cross section of the pipe becomes zero, it is judged that the pipe will be clogged eventually, and the control device commands the injection of the lubricant, so that the pipe clogging can be prevented.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of a pipe clogging position detection device for discharged mud and sand according to the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a table showing experimental results measured by an ultrasonic flow meter.

FIG. 4 is an explanatory diagram showing measurement points on a tube cross section.

FIG. 5 is a block diagram showing an earth removal amount management system.

FIG. 6 is a flowchart showing a management operation in the earth removal amount management system.

FIG. 7 is a cross-sectional view showing the entire tunnel excavation work using the soil discharge management system.

[Explanation of symbols]

 1 Doppler type ultrasonic flowmeter 17 Transducer 19 Control device 29 Ultrasonic transmitter 27 Control unit 31 Ultrasonic receiver P tube

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Haruo Uchida 2-26-48 Akanedai, Midori-ku, Yokohama-shi, Kanagawa (72) Inventor Shigee Shibue 52-8, Tokuhisa, Chikugo-shi, Fukuoka (72) Susumu Fukamachi Taira 2-5-6 Kikugawa, Sumida-ku, Tokyo Escape Co., Ltd.

Claims (4)

[Claims] 1. A device for detecting a closed position in a pipe, wherein a transducer integrally provided with an ultrasonic wave transmitter and an ultrasonic wave receiver of a Doppler type ultrasonic flowmeter is provided on the outer circumference of the pipe. 2. The in-pipe occlusion position detection according to claim 1, wherein a plurality of transducers are provided at an outer periphery of a predetermined position along the pipe, and a control device for determining occlusion based on a signal from an ultrasonic receiver is provided. apparatus. 3. A method for detecting a closed position in a pipe, wherein a Doppler type ultrasonic flowmeter provided on the outer circumference of the pipe detects the closed position inside the pipe when zero flow velocity at a predetermined position in the cross section of the pipe is detected. . 4. When a blockage in the pipe is detected based on a signal from a plurality of Doppler type ultrasonic flowmeters provided on the outer periphery of a predetermined position along the pipe, the controller automatically commands the lubricant injection. A characteristic method for managing the amount of discharged soil.