JPS6239741A - Apparatus for detecting leak position of pipeline - Google Patents

Abstract

PURPOSE:To make it possible to accurately detect a leak position even if the kind and temp. of a liquid vary, by providing a pressure detector to at least three areas and calculating a propagation speed from each pressure variation detecting time before calculating a leak position. CONSTITUTION:A large number of pressure detectors 151-15n are arranged to a pipeline 13 so as to provide intervals l1-ln-1 to each other and telemeter sub-stations 161-16n are respectively arranged to be connected to the telemeter key station 19 of a central control chamber 18 through a line cable 17. When a leak phenomenon is generated in the pipeline 13, the propagation speed of a liquid is calculated from the difference between the detection times of pressure variation detected by three pressure detectors 151-153 and a leak generated position is calculated by using said propagation speed. Therefore, even the kind, temp. and properties of the liquid change, a leak position can be always accurately detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a leak position detection device for a pipeline for transporting liquid.

[Prior art] Generally, in pipelines that transport liquids such as crude oil,
When liquid leaks due to some reason, it is necessary to quickly and accurately detect the location where the leak occurs. Conventionally, a leak position detecting apparatus shown in FIG. 7 has been proposed as one of such leak position detecting apparatuses for detecting the position where a leak occurs in a pipeline.

[Unexamined Japanese Patent Publication No. 49-17289 (Liquid Transport Pipe Damage Detection Device) In other words, the liquid sent from the supply tank 1 is pressurized by the supply pump 2 and is led to the receiving tank 4 via the pipeline 3. It will be destroyed. Gate valves 51 to 5rL and pressure detectors 61 to 6l are arranged at regular intervals (L) in the pipeline 3, and each pressure data signal H1 to Hn detected by each pressure detector 61 to 6n is is transmitted to the control section 7 and monitored by the control section 7. For example, time 1. When a liquid leakage phenomenon occurs at point D of the pipeline 3, a phenomenon in which the pressure of the liquid at the leakage occurrence position decreases occurs. This pressure drop phenomenon propagates in both directions of the pipeline 3 at a pressure wave propagation speed a determined by the properties of the liquid. Then, as shown in FIG. 8, at time t1, the pressure data signal H3 of the pressure detector 5, which is located closest to the leakage occurrence position, decreases. Subsequently, at time t2, the pressure data signal H2 of the pressure detector 62 at the next closest position decreases.

Therefore, the leakage location @D exists between the pressure detector 63 and the pressure detector 62. Assuming that the distance between the leakage location and the pressure detector 63 is X, the following (1) (
2) The formula holds true.

X=a (t+ -to) -(1
) L−X+a (t2− t+1) ”・
(2) Therefore, the distance X to be found is expressed by equation (3).

X-[L-a <t 2-tt ) co/
2-(3) In this way, each pressure detector 61
~6n pressure data signals H1~HrL fluctuation time t,,
It is possible to specify the leakage location from t2.

[Problems to be Solved by the Invention] However, even with the pipeline leak position detection device configured as described above, there are the following problems. That is, in the detection VR position, the propagation velocity a of the liquid pressure wave is fixed to a constant value. However, in reality, the propagation velocity a within the pipeline 3 depends on the liquid density, the adiabatic compressibility of the liquid, etc., and these values vary depending on the temperature and properties of the liquid. Therefore, the propagation velocity a changes greatly in response to changes in the temperature and properties of the liquid. As a result, there is a problem in that a large error occurs when the leakage occurrence position is determined using this propagation velocity a as a constant.

The present invention has been made based on these circumstances, and its purpose is to provide pressure detectors at at least three locations, calculate the propagation velocity from each pressure fluctuation detection time, and then calculate the leak position. Depending on the type of liquid that circulates inside.

To provide a pipeline leak position detection device capable of accurately detecting a leak position even if the temperature, properties, etc. change.

[Means for Solving the Problems] The pipeline leak position detection device of the present invention includes at least three or more pressure detectors arranged along the pipeline to detect the pressure of liquid, and each pressure detector. an interval data memory for storing interval data between the pressure detectors, and a first pressure detector and a first detection time at which a pressure fluctuation first occurred due to a leakage phenomenon occurring in the pipeline. The first detection memory and the second detection memory where the pressure fluctuation occurred second.
a second detection memory that stores the pressure detector and the second detection time, and a third detection memory that stores the third pressure detector and the third detection time where the pressure change occurred third. The first . Second.
The propagation velocity of the liquid pressure wave is calculated using the interval data between the corresponding pressure detectors stored in the third detection time and interval data memory, and the calculated propagation velocity and each interval data stored in each detection memory are calculated. The leak occurrence position is calculated using the detection time and interval data between the corresponding pressure detectors.

[Operation] With the pipeline leak position detecting device configured as described above, when a leak phenomenon occurs in the pipeline at time to, the first detection memory stores the first position closest to the leak occurrence position. Pressure detector and first detection time t1
is stored in the second detection memory, the second closest pressure sensor and the second detection time t2 are stored in the second detection memory, and the third
The detection memory contains the third pressure sensor closest to the third
Detection time t3 is stored. Then, interval data between the pressure detectors and detection time t1 in each pressure detection device are provided. t2. The propagation velocity a of the liquid pressure wave is calculated from the time difference of t3, and the leakage occurrence position is calculated using the calculated propagation velocity a.

[Example code] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a pipeline leak position detection device according to an embodiment. That is, the liquid sent from the starting station 11 is pressurized by the feeding pump 12 and guided to the destination station 14 via the pipeline 13 . pipeline 13
For example, three or more n pressure detectors 151, 152 .
..., 15n are provided, and each pressure detector 15!
~n is 121.12. (A3.-, Qn-+
They are placed at intervals of . Each pressure detector 151~
The pressure data signals H1, H2, . . . , Hn are sent to telemeter slave stations 161, 162, 163, respectively.

..., 16n and the line cable 17 to the telemeter master station 19 in the central control room 18.

The telemeter master station 19 receives each pressure data signal H1~
n is sent to the calculation control section 20. This arithmetic control unit 20 controls the pressure fluctuation time t of each input pressure data signal H1 to rL.
t, t2. From t3, the propagation velocity a of the pressure wave in the liquid flowing in the pipeline 13 is calculated, and the leak occurrence position is calculated using this propagation velocity a, and the calculation result is printed out to the printer 21.

In such a system, time 1. If a leakage phenomenon occurs in the pipeline 13 for some reason, the second
As shown in the figure, at time t1, the signal level of the pressure data signal @H of the pressure detector 15 closest to the leak occurrence position (the code of this pressure detector is Pl) suddenly decreases. Then, at time t2, the pressure of the next closest pressure detector 16 (also P2) and the capacity signal H decrease. Roughly at time t3, the pressure data signal H of the third closest pressure detector 15 (same <Pl) decreases.

FIG. 3 shows, for example, an RA installed in the arithmetic and control unit 20.
The code P1 of the pressure detector 15 where the pressure drop occurred first and the code P1 of the pressure detector 15 where the pressure change was detected are stored in the memory unit 22.
A first detection memory R1 stores the detection time t1 of , and a second detection memory R2 stores the code P2 of the pressure detector 15 where the pressure drop occurred second and the second detection time t2.
゜A third detection memory R3 stores the code P3 of the pressure detector 15 where the pressure drop occurred third and the third detection time t3, the first pressure detector 15 (code P1) and the second pressure detection The interval data area R4 stores interval data L12 indicating the distance between the first pressure detector 15 (Pl) and the third pressure detector 15 (Pl>), and the interval data Lt5 stores interval data Lt5 between the first pressure detector 15 (Pl) and the third pressure detector 15 (Pl>). An interval data memory R6 for storing all the preset interval data λ1, Q2, λ3, . . . , (In-) in FIG. 1 is formed.
This storage unit 22 includes a propagation velocity memory R7 that temporarily stores the calculated correct propagation velocity a, a leakage position data memory R8 that temporarily stores the correct position data X of the calculated leakage position, and a A computation fi RR9 and the like for calculating the position data X are formed.

The calculation control section 20 sends each pressure data signal H1 to r from each pressure detector 151 to n to the telemeter master station 19.
When L is input, the leakage position data X is calculated according to the flowchart shown in FIG. That is, when the main routine is started, the presence or absence of a pressure data signal that rapidly decreases in pressure among the pressure data signals H1 to H1 input to the telemeter master station 19 is monitored, and if such a pressure data signal H is input, Then, the code P1 of the first pressure detector 15 that sent out the pressure data signal H and the time t1 at which the pressure drop was detected are stored in the first detection memory R1 of the storage section 22. Next, the code P2 and detection time t2 of the pressure detector 15 whose pressure data signal H has decreased second are stored in the second detection memory R2, and the code P3 and detection time t3 of the pressure detector 15 whose pressure data signal H has decreased third are stored in the second detection memory R2. The third detection memory R3
Store it in When the storage process in each detection memory R1, 2, and 3 is completed, the interval data memory R-6 is searched to find the code P! and interval data L1 between pressure detector 15 of code P2
z, tj and pressure detector 15 with code P1 and code P3
The interval data L13 between them are read out and stored in the interval data areas R4 and R5, respectively.

When the above process is completed, the leakage position at Pl is located, for example, between the first pressure detector 15 (Pi) and the second pressure detector 15 (R2) (position A) as shown in FIG. The tentative propagation velocity a given by equation (a)
Calculate 2.

a2-113/ (t3-tt) ”(4
) Next, using this provisional propagation velocity a2, provisional position data of this leakage occurrence position A indicated by the distance from the first pressure detector 15 (Pl) to the leakage occurrence position A shown in FIG.
2 is obtained using equation (5).

X2- [Li2-a2 (t2-tt)] =
15) When the temporary propagation velocity a2 and the temporary position data x2 are calculated, it is checked in R2 whether the calculated temporary position data x2 is a negative value. And if it is a negative value, P
The range of the leakage occurrence position assumed in 1 is incorrect, and the leakage occurrence position is the first pressure detector 15 (P
l) and the third pressure detector 15 (Pl) (position B)
Therefore, a provisional propagation velocity a3 expressed by equation (6) is calculated at Pl.

a3-112/ (t2-tl) ・=(
6) Next, similarly to the above, using this temporary propagation velocity a3, calculate the leakage occurrence position B shown in FIG. 6 as the distance from the first pressure detector 15 (P+) to the leakage occurrence position Calculate temporary position data x 3 using equation (7).

X3- [Lu-a3 (t3- tl)] -1
7) When the tentative propagation velocity a3# and the tentative position data Store in position data memory R8. Next, the propagation velocity a and the leakage occurrence position data X read from the memories R7 and R8 are sent to the printer 2 along with information on which side of the first pressure detector 15 (PI) the leakage occurrence position is located. Print out.

Note that if the temporary position data x 2 in R2 is a positive value,
It is determined that the range of the leakage occurrence position assumed in Pl is correct, and the previously calculated provisional propagation velocity a2 and this provisional position data x 2 are stored in the storage unit 22 as the correct propagation velocity a and the correct position data X. Stored in propagation velocity memory R7 and leak position data memory R8.

In the pipeline leak position detection device configured in this way, the propagation velocity a of the pressure fluctuation wave of the liquid generated due to the occurrence of a leak phenomenon is determined by the three pressure detectors 15 each time a leak phenomenon occurs. (PL, R2.

Each detection time tl of pressure fluctuation detected at Pl).

t2. It is calculated based on the difference in t3 and interval data Ltz, Ln. Then, using this calculated propagation velocity a, position data X of the leakage occurrence position is calculated. Therefore, since the propagation velocity a is calculated each time for the liquid actually flowing through the pipeline 13, it does not matter the type of liquid.

Even if the temperature and properties change, the value will always be correct. As a result, the position data X indicating the leak occurrence position also shows a correct value, and the detection accuracy of the leak occurrence position is greatly improved.

Note that the present invention is not limited to the embodiments described above. In the embodiment, each pressure sensor 151.152.・
..., 15n, mutual installation interval 21, λ2. ..., (
2n-+ are set arbitrarily, but if they are all set at equal intervals, the leakage location is always between the first pressure detector 15 (PI) and the second pressure detector 15 (PI) as shown in Figure 5. 15 (R2), and as shown in FIG.
It cannot be located between. Therefore, the process after R2 in the flowchart of FIG. 4 is omitted, and the provisional propagation velocity a is
2 and temporary position data x 2 can be set as the correct propagation velocity a and position data X.

[Effects of the Invention] As described above, according to the present invention, at least three pressure detectors are provided, and the leak position is calculated after the propagation velocity is calculated from each pressure fluctuation detection time. Therefore, even if the type, temperature, properties, etc. of the liquid flowing inside vary, the leak position can be detected accurately.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing a pipeline leak position detection device according to an embodiment of the present invention, FIG. 2 is a diagram showing each pressure data signal of each pressure detector of the embodiment, and FIG. FIG. 4 is a flowchart showing the operation of the embodiment. FIGS. 5 and 6 are diagrams for explaining the operation of the embodiment. FIG. 8 is a schematic configuration diagram showing a conventional leak position detection device, and FIG. 8 is a diagram showing each pressure data signal of each pressure detector of the conventional device. 11... Departure base, 12... Feeding pump, 13...
・Pipeline, 14...Kan base, 151,152.
.... 15n...pressure detector, 161, 162. .... 16... Telemeter slave station, 17... Line cable, 18... Central control m+i, 19... Telemeter master station, 20... Arithmetic control unit, 21... Printer, 22
...Storage unit, R1...First detection memory, R2...
・Second detection memory, R3...Third detection memory,
R6... Interval data memory. Applicant's representative Patent attorney Takehiko Suzue Figure 2 Figure 3 Figure 4 t2 to t1 t3 Figure 5 Figure 6 to tl t2 t3 t4 ts! 1! The 8th (!!

Claims (1)

[Claims] At least three or more pressure detectors arranged at predetermined intervals along a pipeline and detecting the pressure of the liquid flowing in the pipeline, and each pressure information sent from each of these pressure detectors. an interval data memory for storing interval data between the respective pressure detectors; and a first interval data memory for storing interval data between the respective pressure detectors; a first detection memory that stores a pressure detector and a first detection time; a second pressure detector and a second detection time at which a second pressure change occurs due to the occurrence of the leakage phenomenon; and a third detection memory that stores a third pressure detector and a third detection time in which a pressure change occurred third due to the occurrence of the leakage phenomenon. , the propagation velocity of the pressure wave in the liquid is determined using the first, second, and third detection times stored in each detection memory and the interval data between the corresponding pressure detectors stored in the interval data memory. a propagation velocity calculation means for calculating the leakage occurrence position using the propagation velocity calculated by the propagation velocity calculation means, each detection time stored in each detection memory, and the interval data between the corresponding pressure detectors. 1. A pipeline leak position detection device comprising: a leak occurrence position calculation means for calculating the leak position.