JPH032539A - Leak inspection method for cylindrical article - Google Patents

Abstract

PURPOSE:To easily and securely detect a leak in the cylindrical article by pressing high-temperature liquid in the cylindrical article and detecting infrared rays emitted from respective parts of the surface of the cylindrical article. CONSTITUTION:A freon hose 10 is a hose such as a fuel hose and plural hoses like this are arranged; and both end parts are connected to conduits 14 through manifolds 11 and seal jigs 12 and high-temperature gas is supplied into and discharged from them through the opening/closing operation of solenoid valves 16. Further, a thermography device 18 has an infrared camera 20 and a cathode- ray tube 22. Then the hoses 10 are sealed in a constant pressure-applied state after the high temperature gas is supplied into the hoses 10, and an image of the whole hoses 10 is picked up by the camera 20 and displayed on the cathode-ray tube 22. If there is a leak in a hose 10, the high-temperature gas flows out of the part, so that is detected by the camera 20 and displayed on the screen of the cathode-ray tube 22, so that the leak is detected immediately.

Description

[Detailed description of the invention] (Industrial use! 7) The present invention relates to a leakage testing method for cylindrical products such as hoses.

(Prior art and problems to be solved by the invention) Conventionally, as a method for testing for leaks in hoses, a halogen-based gas is sealed inside the hose (a hose with a cap or a hose itself), and the gas flowing out from the leakage part is detected. There is a method of checking whether there is a leak in the hose by detecting the leakage, or by filling the inside of the hose with high-pressure gas such as nitrogen, submerging the entire hose in water, and visually checking whether bubbles are generated from the leakage part. There are known methods for testing the presence or absence of leaks.

However, in the case of the method mentioned in the song title, there are problems in addition to the large scale of the inspection equipment, which is accompanied by danger, and in the case of the latter method, water gets into the hose during the inspection and remains attached to the hose even after the inspection. There are problems, such as the possibility that it may remain. Particularly in Freon hoses for transporting refrigerant for automobiles, fuel hoses, etc., residual moisture can cause serious defects. If the product is used without proper drying, it may cause an accident.

(Means for Solving the Problems) The present invention has been made to solve such problems, and its gist is to introduce and pressurize a high-temperature fluid into the inside of a cylindrical product such as a hose, and to The purpose of this method is to detect the presence or absence of leakage by using a thermography device to detect infrared rays emitted from various parts of the surface of the product.

(Function and effect of IJJ) In the method of the present invention, if there is a leak in any part of a cylindrical article such as a hose, the high temperature fluid sealed inside will flow out from the leak part. A large amount of infrared rays are then emitted from the leak, which is detected by a thermography device.

Therefore, according to the method of the present invention, leakage of tubular articles such as hoses can be easily and reliably inspected, and there is no danger associated with the inspection.

In the present invention, various types of high-temperature fluids are used, but in particular, if gas is used as the fluid, there is no need for a drying process after the inspection, which has the advantage of reducing the number of processes. There is no risk of moisture remaining attached to the hose, and therefore, problems caused by moisture attachment can be avoided even in automotive hoses such as Freon hoses and fuel hoses.

(Example) Next, embodiments of the present invention will be described in detail based on the drawings.

In FIG. 1, IO is a hose such as a Freon hose or a fuel hose, and a plurality of such hoses IO are lined up,
Both ends thereof are connected to the conduit 14 via the manifold 11 and the sealing jig 12, and by opening and closing the solenoid valve 16, high-temperature waste, such as high-temperature air heated by an air heating device (not shown), is pressurized inside. It is designed to flow in or be discharged in the same state.

A thermography device 18 includes an infrared camera 20 and a cathode ray tube 22.

In the inspection method of this example, high-temperature gas is introduced into the inside of the hose 10 and then sealed under a constant pressure.
The whole thing was captured by an infrared camera 20 and captured by a cathode ray tube 22.
Display the image above. If there is a leak in the hose 10, high-temperature scum flows out from the same portion, and this is detected by the infrared camera 20 and displayed on the screen of the cathode ray tube 22, so that the presence or absence of a leak can be immediately detected.

With this method, there is no risk of moisture remaining on the hose 10 after the leakage test, so there is no need to dry it after the test, and there is also a risk of problems due to dry brown matter or forgetting to dry it. do not have.

In this example, a gas such as air is used as the high-temperature fluid, but it is also possible to use a liquid as the high-temperature fluid. It is also possible to detect infrared rays emitted from the hose, take a photograph of the temperature pattern, and use this to inspect for leaks.

In addition, it is also possible to apply the present invention to cylindrical articles such as metals other than hoses such as bipeds, etc. The present invention can be modified in various ways based on the knowledge of those skilled in the art without departing from the spirit thereof. It is possible to implement the method with some modifications.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an inspection method that is an embodiment of the present invention. 10: Hose 18: Thermography device

Claims (1)

[Claims] A tube such as a hose, characterized in that a high temperature fluid is introduced and pressurized into the interior of the tube, and the presence or absence of leakage is detected by detecting infrared rays emitted from various parts of the surface of the tube with a thermography device. How to check for leaks in products.