JPS6117037A - Leaking liquid detecting method - Google Patents

Abstract

PURPOSE:To make it possible to detect presence or absence of minute amount of leakage accurately, by compounding a fluorescent material into a liquid, and detecting the fluorescent action at the outside of the using place of the liquid. CONSTITUTION:A fluorescent material is compounded in a liquid whose leakage poses a proble. The fluorescent action at the outside of the using place of the liquid is detected, and the presence or absence of the leakage of the liquid is detected. For example, leakage poses a problem in connecting parts, sealing parts and the like of fuel tanks, oil tanks and pipings in fuel systems and lubricating systems in automobiles and aircraft. Therefore the fluorescent material is compounded in the liquids such as fuel oil like gasoline and lubricant. As the fluorescent material, diphenyl hydrocarbon, whose general formula is shown by the formula I (R1 and R3 in the formula can be the same or different, they are hydrogen or hydrocarbon group, and R2 is not hydrogen), is used. Especially, diphenyl shown by the formula II is recommendable. Hydrocarbon having other composition can be used.

Description

[Detailed description of the invention] [Technical field] The present invention detects the presence or absence of minute leaks of various liquids.

Regarding how to.

[Background technology] Fuel oil in fuel systems and lubrication systems of various mechanical devices,
Leakage of lubricant not only impairs the functionality of mechanical devices, but may also cause serious accidents. Therefore, in order to prevent such leakage phenomena in advance in various mechanical devices, detection of the presence or absence of leakage is performed as part of maintenance work. However, in the conventional detection method, the presence or absence of oozing of fuel oil or lubricant was determined visually after the operator completely wiped off the oil and dust stains from the detection area with a cloth or the like. Therefore, such conventional methods rely heavily on the skill of a single worker, and it is difficult to detect minute amounts of leakage.Moreover, in areas that cannot be directly reached by the worker, oil, dust, etc. Since it is impossible to wipe away the leakage, it is impossible to detect the presence or absence of leakage.

[Object of the Invention] The object of the present invention is to provide a detection method that can accurately detect the presence or absence of a minute amount of leakage without requiring special skill and even in a place that is out of the direct reach of an operator. It is about providing.

[Structure of the Invention] Therefore, the present invention provides a method for detecting the presence or absence of leakage of the liquid by blending a fluorescent substance into a liquid whose leakage is a problem and detecting the fluorescent effect on the outside of the place where the liquid is used. This aims to achieve the above objective.

The places where the liquid is used, that is, the apparatus to which the present invention is applied, are, for example, various types of transportation machinery such as automobiles, railways, and aviation.
Fuel systems and lubrication systems in various mechanical devices such as molding equipment and machine tools, among which the presence or absence of leakage is particularly problematic are fuel tanks, oil tanks, joints and seals of piping, etc.

The liquid referred to in the present invention is gasoline, jet fuel, diesel oil 1
In addition to fuel oil in general such as heavy oil, and lubricants in general such as engine oil and gear oil, this includes almost all liquids whose leakage is a problem.

The fluorescent substance referred to in the present invention is mainly a hydrocarbon fluorescent substance, and in addition to compounds consisting of carbon atoms and hydrogen atoms,
A fluorescent substance containing carbon atoms, hydrogen atoms, and other foreign atoms such as nitrogen, oxygen, sulfur, phosphorus, halogen, etc.

(In the formula, R'+ and R3 may be the same or different and each represents hydrogen or a hydrocarbon group, provided that R
+ is not hydrogen. ), especially diphenylethane represented by R3 (wherein R1 and R2 may be the same or different and each represents hydrogen or a hydrocarbon group). Naphthalene hydrocarbons represented by; anthracene, methylanthracene, ethylanthracene, 2 represented by (wherein R+, R2, and R3 may be the same or different and each represents hydrogen or a hydrocarbon group) ,7-dimethylanthracene,1-,'
3, 6', 8-tetramethyl'anthracene etc. are preferred; Among the phenanthrene hydrocarbons represented by the formula, in particular, methylphenanthrene or ethylphenanthrene is preferred: (wherein R1 and R2 may be the same or different and each represents hydrogen or a hydrocarbon group. ) naphthacene represented by p; chrysene represented by p (wherein R+ and R2 may be the same or different and each represents a hydrogen or hydrocarbon group): (wherein R1 and R2 are Pyrene represented by (which may be the same or different and each represents a hydrogen or hydrocarbon group); l', 2', 7', 8'-sinafsazine, 1
',2',8',9'-Cinadisazine;1,2,4-hydroxyanthraquinone; 2,5-dihydroxyterephthalic acid; 3-nitro-4',4''-dihydroxytriphenylmethane; Nenzo Oxacylyl compounds such as oxazolylstilbenes, benzoxacylylthiophenes, benzoxacylylbiphenyls, and hendioxazolylethylenes can be mentioned.

In the present invention, the amount of fluorescent material added to the liquid is 0.01% by weight to 1 liter based on the weight of the liquid.

It is preferably in the range of 0% by weight, and 0. O1 weight%
If it is not swirled, the fluorescent effect generated is weak and difficult to detect, and if it exceeds 1.0% by weight, it is economically disadvantageous because expensive fluorescent material is wasted. It is. It is usually around 0.1% by weight.

As mentioned above, the amount of fluorescent material added is very small, so the liquid after mixing will not deteriorate the original characteristics required of the liquid, such as performance as a fuel and performance as a lubricant. do not have.

For detecting leaks, various electromagnetic waves with wavelengths shorter than infrared wavelengths, such as infrared, visible, and ultraviolet radiation, are used outside the point where the liquid is used.

This can be easily achieved by irradiating X-rays or cathode rays in particular, but in some cases the fluorescent effect can be perceived by natural light.

If there is any leakage, the fluorescent substance in the liquid will be excited by the action of the irradiated electromagnetic waves and will produce a fluorescent effect, and this fluorescent activity will be easily noticed and a trace amount of leakage will be confirmed.

Further, in the leakage detection method of the present invention, by adding a dye, liquid leakage can be detected more easily. The dye is not particularly limited as long as it is soluble in the liquid used. These dyes include various dyes such as red, blue, green, and brown, and can be appropriately selected depending on the color of the mechanical components used. For example, as a dye used in lubricating oil, "Oil Fine Green B J" manufactured by Shirad Co., Ltd.
, rLIQUID BROWN RHJ ,
Manufactured by Mortorn Chemi-cal Co, rAU
TOMATE BLUE No8 J, rAuto
mateRED IKJ, rAUTOUIITE GR
EEN 1) IFJ, rAUTOMATERE
D-BJ, rSpiritJ manufactured by Sumitomo Chemical Co., Ltd., rAizen 5pilonJ manufactured by Hodogaya Chemical Co., Ltd.,
Manufactured by Shiraki Kagakusei Co., Ltd.
There are J etc. The blending amount of these dyes is preferably in the range of 0.01 to 1% by weight based on the weight of the lubricating oil.

If the amount is less than 0.01% by weight, the effect of confirming the presence or absence of oil leakage will be weak, and if it is added more than 1% by weight, the dye will be wasted, which is economically disadvantageous. It is usually around 0.1% by weight.

[Effects of the Invention] As described above, according to the present invention, it is possible to accurately detect the presence or absence of a small amount of leakage without requiring special skill and even in a place that is out of the direct reach of the operator. A detection method that can be used can be provided.

[Description of Examples] Example 1 2.2'(2°5-thiophenedyl)bis(5-t-butyl-benzo A lubricating oil was prepared by blending an amount equivalent to 0.5% by weight of oxazole).

A crack was intentionally made in the oil pan seal of a commercially available diesel engine, the engine was assembled, the lubricating oil was injected into the engine, and the engine was idled for 30 minutes at an oil temperature of 250°C.

When oil leakage from the cracks was investigated using ultraviolet irradiation with a wavelength of 385 mm, clear fluorescence was confirmed.

Example 2 In Example 1, Shira? Co., Ltd. was used as the dye. When the same procedure was carried out by adding an additional amount equivalent to 0.1% by weight of the product name Oil Fine Green, very clear fluorescent light emission was observed, and the oil leakage site was instantly discovered.

Claims (1)

[Claims] (1) A method for detecting liquid leakage, which comprises adding a fluorescent substance to the liquid, and detecting the presence or absence of leakage of the liquid by detecting the fluorescent effect on the outside of the area where the liquid is used.