JPH0469328B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to improving the efficiency of leak testing of sealed tanks for storing electrical equipment and downsizing test equipment.

[Prior art]

Sealed tanks for storing electrical equipment that contain cooling and insulating fluid are generally manufactured by welding steel plates, and flanges for connecting radiators and other accessory equipment are welded to them, so they must be prepared before storing electrical equipment. A leakage test is performed using a verification medium to check for fluid leakage due to defects in these welded parts.

This conventional leakage test will be explained with reference to FIG.

In the figure, 1 is the main body of the sealed tank, and 2 is the lid of the sealed tank.The main body 1 and the lid 2 are tightened with a C-clamp 4 via a gasket 3 to seal them.
5 is a valve provided in the main body 1.

For the leak test, after evacuating the sealed tank A,
This is done by filling and pressurizing the verification medium 6 into the sealed tank A through the valve 5.

For this reason, as the volume of the sealed tank A increases, the amount of verification medium 6 used becomes large, and after the test is completed, this verification medium 6 is removed from the sealed tank A and collected in the recovery tank. Filling, pressurizing, and extracting are time consuming and inefficient, and the equipment for collecting the verification medium 6 is also large, so the core is sealed inside a sealed tank.
Methods have also been implemented to reduce the required amount of verification refrigerant 6. In this method, the core sealed inside the sealed tank 1 moves during the test, and the dimensions and shapes of the sealed tanks 1 are different, so there is a problem that many types of cores are required. It was hot.

[Summary of the invention]

The present invention has been made in view of the above-mentioned problems, and the core sealed in the sealed tank has a structure that prevents movement within the sealed tank, and the structure of the core is formed into a shape of the sealed tank by combining blocks. , provides a leak test method that can accommodate variations in dimensions.

[Embodiments of the invention]

FIG. 2 shows an intermediate process of an embodiment of the present invention, in which the core 7 is inserted into a sealed tank A and sealed using the packing 3 and the C clamp 4 (not shown). A leakage test is performed by evacuation, filling and pressurizing the verification medium 6 as in the conventional method.

The core 7 in this embodiment is a sealed empty tank,
It is a tank with an external volume smaller than the internal volume of the sealed tank A, which is almost similar to the main body 1 of the sealed tank A, and has a negative pressure resistance that can sufficiently withstand the vacuum and pressurization during the test.
It has pressurizing strength. Further, as shown in FIG. 3, in order to prevent the core 7 from moving within the sealed tank A, a plurality of support bolts 8 oriented in the radial direction are arranged radially on the upper surface of the core 7. Reference numeral 9 denotes a bolt seat fixed to the periphery of the upper surface. Furthermore, core 7
A plurality of guide seats 10 projecting radially in the radial direction are provided at the bottom of the guide seat 10.

In this embodiment, the core 7 occupies most of the internal volume of the sealed tank A, and the verification medium 6 is filled in the space formed by the inner surface of the sealed tank A and the outer surface of the core 7, so that both are in close proximity. If the size of the core 7 is determined in such a manner, the required amount of the verification medium 6 can be significantly reduced.

Furthermore, since the core 7 of this embodiment is a hollow tank, it is lightweight and easy to transport and insert/remove into the sealed tank A.

The above example shows the case where one core 7 is used, but the core 7 can be combined with core blocks of dimensions that are easy to assemble to match variations in the shape and dimensions of the sealed tank. If the core is formed to match the internal shape of the sealed tank, there is no need to prepare a core for each sealed tank.

〔Effect of the invention〕

As explained above, the present invention uses a leak test method that uses a core to reduce the amount of verification medium, and the core is connected to the inner wall of a sealed tank by means of guides at the bottom of the core or support bolts provided radially. Since the spacing can be kept constant, the core will not move during the test. Furthermore, since the core is formed by a combination of blocks, variations in the shape and dimensions of the sealed tank can be easily accommodated.

[Brief explanation of the drawing]

Fig. 1 is a side view for explaining the conventional leak test, Fig. 2 is a side view showing the core insertion process when carrying out the leak test of the present invention, and Fig. 3 is a side view for explaining the leak test according to the present invention. It is a side view of the example core. In the figure, 1... the main body of the sealed tank, 2...
Sealed tank lid, 3...Putskin, 4...C clamp, 5...Valve, 7... Core, 8... Support bolt, 9... Bolt seat, 10... Guide seat.

Claims (1)

[Scope of Claims] 1. After inserting a core having an external volume that can be accommodated into the inner space of a sealed tank for storing electrical equipment in which a cooling/insulating fluid is sealed, the insertion port is closed, and the inner surface of the sealed tank is In a leakage test conducted by pressurizing and sealing a verification medium into the space formed between the core and the outer surface of the core, the core is equipped with a plurality of fixing bolts that are pushed out toward the inner wall of the sealed tank. A method for testing leakage of sealed tanks. 2. The leak test method for a sealed tank according to claim 1, wherein a plurality of guides are provided at the bottom of the core that protrudes toward the inner wall of the sealed tank. 3. Leakage in a sealed tank according to claim 1 or 2, characterized in that a core formed by combining a plurality of core blocks is used in accordance with the shape of the internal space of the sealed tank. Test method.