JPS5975132A - Testing method of tightness of closed container - Google Patents

Abstract

PURPOSE:To conduct a test by an easy method by forming a groove between packings with different flange diameters, and pressing a testing medium from plural holes which communicate with the groove and the outside. CONSTITUTION:Plural casings 1, 2, and 3 are provided with flanges 4, 41, 5, and 6 and clamped tightly to one another by a bolt 7 through annular packings 8 and 9 having different diameters. One of flanges to be coupled is provided with a groove 10 concentric with the packings between the packings 8 and 9 and communicate with the outside through holes 11. For a test of tightness, a plug 12 attached to the hole 4 is detached and a pressure device (not shown in a figure) is connected thereto to check whether the medium leaks from a flange connection surface or not. Consequently, a small amount of testing medium is required, so a small-capacity pressure device is usable and the test is conducted easily.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for testing the sealability of a joint of a closed container that is constructed by joining a plurality of casings and in which a pressure difference exists between the inside and outside of the container.

Pulp for pulp-type tubular water turbines and generators is known as belonging to this type of closed container.

In this case, the pulp can be thought of as a large, thin-walled external pressure vessel that is always submerged in water, and water pressure is constantly acting on the outside of the container, so it is important to take measures to prevent water from leaking into the inside of the pulp. . Pulp is usually divided into casings slightly axially apart due to transport restrictions.
It will be assembled on site by firmly tightening the joints of each gauging using gaskets and bolts. Therefore, in order to confirm the watertightness of the completed pulp, it is necessary to test for the possibility of water leakage at the joints.

Conventionally, this type of sealing test method is known to use a suitable test medium inside the assembled pulp, apply a predetermined pressure, and test for leakage of the medium at the joint. . However, this method has the following drawbacks. That is, in order to maintain the internal pressure of the pulp due to the medium at a predetermined value during the sealability test, parts that are originally connected directly or indirectly to the outside, such as inspection shafts, wiring, or piping joints, are completely removed. It is necessary to seal it, and this sealing work is extremely complicated and requires a lot of man-hours, resulting in unnecessary expense.

Furthermore, since the internal volume of the pulp to be tested is relatively large, the pressurizing equipment for pressure cooling for testing must be large-scale, which is also uneconomical. I can't escape it.

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks of conventional sealing test methods, it is an object of the present invention to provide a test method that can reliably confirm sealing at a joint using very simple means.

According to the present invention, the above object is to connect a plurality of casings by a flange, and the seven flange is provided with at least two ring-shaped packings of different diameters for sealing, and is formed into a cylindrical shape and has an inner and an outer part. In an airtight container in which a pressure difference exists between the seals, a ring-shaped groove concentric with the seal is provided between the seals having different diameters on the joint surfaces of one of the seven flange and the seal. ,
In addition, a plurality of holes are formed through the inside of the seven flange to communicate the wire groove with the outside, and the opening of the wire hole to the outside is normally closed, and during testing, a pressure device is used to open the wire hole from the opening of the wire hole. This is accomplished by pressurizing the medium and performing a leak test.

Next, the present invention will be described in detail based on embodiments shown in the drawings.

In FIG. 1, the pulp of the pulp-type tubular water turbine/generator is composed of a stator frame 1, a top cover 2, and a casing of 303 stay vanes. In order to connect these casings to each other, the stator frame 1 has 7 flange 4 and 41 for connecting the stator frame, the top cover has 7 langes 5 for connecting the top cover, and the stay vane 3 has a stay vane. A connecting flange 6 is provided, respectively. At the joints between the stator frame 1 and the top cover 2 and between the stator frame 1 and the stator frame 3, as shown in the partially enlarged views of FIGS. 2 and 3, the stator frame joints 7 are
Ring-shaped packings 8 and 9 of different diameters are arranged on the joint surfaces of the flange 4 and 41, respectively, and are arranged concentrically with the inner surfaces of the joint flanges 4 and 41 of the stator frame, and the joint flange 4 and the top of the stator frame The 7 langes 5 of the cover, the connecting flange 41 of the stator frame, and the 7 langes 6 of the stay vane all press the packings 8 and 9 and are strongly tightened with the bolts 7 to form the pulp as a sealed container. . Furthermore, a ring-shaped groove lO is provided on the joint surface of the flanges 4 and 41 for connecting the identifier frame, which is located between the seals 8 and 9 and is also concentric with the inner surface of the 7 flange to test the tight gripping property. In addition, the ring-shaped groove 10 is connected to the stator frame 1 through the inner surface of the 7 flange 4 and 41 for connecting the stator frame.
A plurality of holes 11 are inserted into the inside of the stator frame 7 for connecting the stator frame.
Lunges 4 and 410 hang radially into the body. The hole 11 is normally closed by a plug 12.

The sealing performance of the pulp consisting of the stator frame 1, top cover 2, and stay vane 3 was tested by removing the plug 12 and opening the hole 1.
Connect a pressurizing device (not shown) installed separately to 1, pressurize the test medium at a predetermined pressure into the hole, and determine whether or not there is leakage of the medium from the 7-flange joint surface (5). It can be carried out easily and reliably, and only a small amount of test medium is required, so a pressurizing device with a particularly large capacity is not required.

As mentioned above, since the gaskets 8 and 9 are arranged concentrically with the sealing test groove 10 in between, it is preferable to use one gasket as a backup for the other gasket.

Furthermore, if the sealing performance of the packing 8 is impaired in a sealed container such as pulp that is subjected to external pressure, and there is concern about the sealing performance of the packing 9 as a backup, the ring-shaped seal can be inserted through the hole 11 without removing the top cover or stay vane. Another advantage is that the flange joint surface can be easily sealed by injecting synthetic resin into the groove 10.

The present invention is not limited to closed containers that receive high water pressure from the outside, such as the pulp of the above-mentioned pulp type tubular water turbine/generator, but is generally a closed container that is formed from a plurality of casings and has a pressure difference between the inside and outside. Needless to say, it is effective (6) for testing the sealing properties of joints in general.

As explained above, the present invention connects a plurality of casings by a flange, and the flange is provided with at least two ring-shaped packings of different diameters to seal the casing, and the casing is formed into a cylindrical shape and has an inner and an outer part. In an airtight container where a pressure difference exists, a ring-shaped groove is provided between the packings having different diameters at the front of the fitting surface of one of the flanges, and a ring-shaped groove concentric with the packing is formed, and A number of holes are made along the inside of the wire hole to communicate with the outside, and the opening of the wire hole to the outside is always closed, and during testing, a suitable test medium is applied from the opening of the wire hole using a pressurizing device. By performing a leakage test by applying pressure, it is possible to easily and reliably test the tightness of the flange joint, since there is no leakage of the medium from the flange surface, and the required test can be carried out easily. Since only a small amount of the medium is required, there is no need for a pressurizing device with a large capacity.Furthermore, if the sealing performance of the sealing gasket is impaired, synthetic resin can be injected into the ring-shaped groove through the hole. This has the effect that the seven-lunge joint surface can be easily sealed without dismantling the closed container.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a side cross section of the sealed container of the present invention (merno of a valve type tubular water turbine generator), and Fig. 2 is a schematic diagram of a cross section of the sealed container of Fig. 1, viewed in the ■-■ direction. , and also the third
The figure represents a partially enlarged view of the flange joint section viewed in the l-1 direction in the cross-sectional view of FIG. 2. DESCRIPTION OF SYMBOLS 1... Stator frame, 2... Top cover, 3... Stay vane, 4.41... Stator frame coupling flange, 5... Top cover coupling flange, 6... 7 langes for connecting stay vanes, 10...ring-shaped groove, 11...hole. 1 Figure 20 73 Mouth

Claims (1)

[Claims] 1) The casing is connected by a plurality of flanges, and the seven flange is provided with at least two ring-shaped gaskets of different diameters for sealing, and is formed into a cylindrical shape so that there is a pressure difference between the inside and outside. In the airtight container, a ring-shaped groove is provided between the packings having different diameters on the joining surface of one of the flanges, and a ring-shaped groove concentric with the packing is provided, and a line groove is formed through the inside of the seven flange. It has multiple holes that communicate with the outside, and the opening of the wire hole to the outside is normally closed, and during testing, a suitable test medium is pressurized from the opening of the wire hole using a pressurizing device to perform a leakage test. Test method for sealing of airtight containers.