JPH0334687Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] This invention relates to a liquid leakage detection line for detecting liquid leakage, and in particular, it not only detects the occurrence of liquid leakage, but also specifically detects the location of the liquid leakage. This relates to a liquid leakage detection line that can be used. [Prior Art] In the storage and transportation of various liquids such as water, chemicals such as sulfuric acid and hydrochloric acid, oils such as crude oil and petroleum, and solvents, leakage can cause losses and accidents, and can also cause damage to computer rooms. If liquid leaks in storage rooms for various materials, etc., there is a risk that various equipment may malfunction or the materials deteriorate, so it goes without saying that measures must be taken to prevent liquid leaks. If this occurs, it must be detected early to prevent losses and accidents. Liquid leakage is generally detected using a detection wire whose electrical characteristics change when liquid enters.Such detection wires include wires with a braid interposed between two conductors, fiber tape, etc. It is known that two electrode wires are woven parallel to each other through an insulator. By the way, in liquid leakage detection, there are cases where it is desired to identify the area where the leakage occurs (hereinafter referred to as the liquid leakage area) at the same time as detecting the occurrence of the liquid leakage itself. This was done using multiple leakage detection lines. That is,
For example, as shown in Fig. 3, the detection target area A is divided into several areas S ₁ , S ₂ , ..., and one leakage detection line 1 ₁ , 1 ₂ , ... is attached to each of these areas. The measuring device 2 placed in the monitoring center and the starting ends of each leakage detection wire 1 ₁ , 1 ₂ , ... are connected to the normal lead wires L ₁ , L ₂ , ... that are not sensing leakage, respectively. tied to,
The method used was to discover leakage areas by finding lines where the electrical characteristics had changed. [Problems that the invention aims to solve] In the conventional liquid leakage detection technology using liquid leakage detection wires as described above, a large amount of lead wires are used in addition to the liquid leakage detection wires, which not only increases costs but also However, sufficient consideration must be taken to prevent breakage, short-circuiting, or insulation deterioration of the lead wires, making installation and maintenance work that much more troublesome. This idea was created in view of the above circumstances, and its purpose was to eliminate the need to install lead wires between the area to be detected for liquid leakage and the monitoring center, etc., and to be able to install them easily. The object is to provide a leakage detection line that requires almost no maintenance. [Means for solving the problem] In order to solve the above problem, in this invention, three or more electrode wires insulated by an insulator that allows liquid to pass through each other are connected almost parallel to each other. In a liquid leakage detection line which is arranged as an integral part, the three or more electrode wires mentioned above are two main electrode lines of the same length and auxiliary electrode wires whose number is one less than the number of liquid leakage detection areas. The two main electrode wires have their terminal ends connected through a resistor of a predetermined value, and each of the auxiliary electrode wires has a starting end substantially aligned with the starting end of the main electrode wire, and a terminal end thereof,
The far end of each liquid leakage detection line except for the final liquid leakage detection line area is connected to one of the main electrode lines via a resistor of a predetermined value. [Function] As shown in Fig. 1, the function of the liquid leakage detection line of this invention having the above-mentioned configuration is as follows: The liquid leakage detection target area B is divided into six areas B ₁ , ..., B ₆ , and the liquid leakage detection line is The case of detecting an area will be explained. In FIG. 1, the leak detection line 10 has a pair of main electrode wires 11a and 11b of the same length, and five electrode wires 12 to 16 that are shorter than these main electrode wires and have different lengths. However, the starting ends of each of these electrode wires are connected to terminals at the near end NE of the detection target area B, respectively. Further, the terminal ends of the main electrode wires 11a and 11b are connected to each other by a resistor R ₀ at the far end FE of the detection target area B, and the terminal ends of the auxiliary electrode wires 12, _. ..., resistance R ₁ at the far end of B ₆ ,
..., R ₅ is commonly connected to either one (11a) of the main electrode wires 11a, 11b. Note that the above-mentioned terminating resistors R ₀ , . . . , R ₅ have substantially the same resistance value. Each of the above-mentioned electrode wires is insulated to allow liquid to pass through each other, and if there is no leakage in any of the above areas, the measuring device 17 is used at the near end NE to connect the terminal to the other terminal,... When we sequentially measure the resistances between them, we find that they are mainly caused by each of the above-mentioned terminating resistances R ₀ ,...,
A resistance greater than the predetermined value determined by _R5 is measured, but if leakage occurs in any section, the insulation between the terminal and the leakage section will be reduced due to the drop in insulation caused by the passage of liquid through the insulator between the electrode wires. The resistance between each terminal connected to the main electrode wire 11a other than the main electrode wire 11a is lower than a predetermined value, and the combinations of terminals in which the resistance between the terminals is lower than the predetermined value are shown in the table below. As shown, it differs depending on each section, so for example, the measuring device 17 and the terminals are installed at the monitoring center.
..., and by measuring the resistance between the terminal and the terminal as described above, the leakage section can be identified. For example, if the resistance between terminals - and - is lower than the specified value, use the interval according to the table below.
B ₂ can be identified as the leakage section.

〔Example〕

In FIGS. 2a and 2b, the leakage detection wire 10 according to an embodiment of the present invention includes two main electrode wires 11a covered with a non-hygroscopic internal braided layer 18 made of polyethylene monofilament yarn or the like. ,11
Seven electrode wires consisting of b and five auxiliary electrode wires 12 to 16, which are shorter than these main electrode wires and have different lengths, are twisted at an appropriate pitch with their starting ends aligned with each other, and a Tetron multi-layer wire is placed on top of them. It has a structure in which the entire length is covered with a liquid-absorbing outer braided layer 19 made of filament yarn or the like. In this case, the outer diameter of the leakage detection wire becomes gradually thinner from the starting end to the end of each auxiliary electrode wire, but if it is desirable to have the same outer diameter over the entire length, then after each auxiliary electrode wire , inner braid layers of the same diameter or other materials may be successively twisted together. The leakage detection wire 10 of this embodiment is constructed by removing the outer braided layer 19 and the inner braided layer 18 at the terminal ends of each of the auxiliary electrode wires 12,..., 16, and using resistors or resistance wires having approximately the same value. After commonly connecting it to either one of the main electrode wires 11a or 11b, repairing the coating as appropriate, and similarly connecting the terminal ends of the two main electrode wires via a resistor, it is easy to install. As explained in the [Operation] section, by measuring the resistance on the starting end side, when leakage occurs, the area can be easily identified. In this example, the reason why the inner braid layer 18 is non-hygroscopic and the outer braid layer 19 is hygroscopic is because
Significant leakage resistance occurs between the electrode wires only when liquid leaks, preventing malfunctions due to high temperature and humidity, etc.
This is to ensure that liquid leakage can be detected.
Moreover, the above-mentioned terminating resistors may be connected in advance at the time of manufacturing the leakage detection wire. FIG. 4 shows another embodiment of the liquid leakage detection wire of this invention. In this embodiment 1, two main electrode wires 21a and 21b, both made of steel wire, are attached to the braided body layer 20 of polyethylene monofilament. and two auxiliary electrode wires 22 and 23, which are shorter than these main electrode wires and have different lengths, are buried almost parallel with their starting ends aligned, one of the main electrode wires 21a and each electrode wire 22. , 23 are commonly connected to the other electrode wire 21b by a resistance wire 24 having approximately the same resistance value. [Effects] As explained above, according to this invention, a leakage detection line can be obtained that is easy to install, requires almost no maintenance, and can reliably detect a leakage location.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram for explaining the principle of liquid leakage detection using the liquid leakage detection line of this invention, and Figure 2a is an internal exploded view of a part of an embodiment of the liquid leakage detection line of this invention. A perspective view, FIG. 2b is a cross-sectional view near the starting end, FIG. 3 is a circuit diagram showing the principle of leak area detection according to the prior art, and FIG. 4 is another embodiment of the leak detection line of this invention. FIG. 10...Leakage detection wire, 11a, 11b...Main electrode wire, 12, 13, 14, 15, 16...Auxiliary electrode wire, 18...Insulator (inner braided body layer), 19...
...Outer braid layer, 20...Insulator (braid layer),
21a, 21b...Main electrode line, 22, 23...Auxiliary electrode line.

Claims (1)

[Claims for Utility Model Registration] (1) In a liquid leakage detection wire 10 which is formed by integrating three or more electrode wires insulated by an insulator 18 that allows liquid to flow through them and arranged substantially in parallel, Three or more electrode wires are connected to two main electrode wires 11a, 11b of the same length, and leakage detection areas B ₁ , B ₂ .
The number of auxiliary electrode wires 12, 13 is one less than the number of
..., both main electrode wires 11a, 11b
are connected at their terminal ends via a resistor R ₀ of a predetermined value, and the starting ends of each of the auxiliary electrode wires 12, 13, etc. are aligned almost with the starting ends of the main electrode wires 11a, 11b, and the terminal ends are connected to each other through a resistor R0 having a predetermined value. It is confirmed that the far ends of _each of the liquid leakage detection lines B _{2 , B 3 .} Characteristic leakage detection line. (2) The insulator 18 is formed of a braided body of non-hygroscopic synthetic fiber threads, and an external braided body is formed by twisting three or more of the electrode wires and having a liquid-absorbing thread around the outer periphery. 19. A liquid leakage detection wire according to claim (1) of the utility model registration, characterized in that the wire is integrally coated with 19.