CS199048B1 - Chamber body for vacuum leakage test - Google Patents

Description

The invention relates to a chamber body for vacuum leak testing.

Until now, the vacuum leak test chamber has been performed with a simple circumferential seal of moss rubber and sealed with various lubricants and sealants, the sealing surface on the test parts being treated by manual grinding and polishing to improve the tightness.

The disadvantage of the previous embodiment was that only e difficulties reached the required tightness, preparation for the test was lengthy and testing had to be interrupted frequently and the chamber rewarded. Adjusting the sealing surface to the test parts was laborious and costly. These drawbacks were most noticeable when testing longer joints, where the suction chamber proceeded by stepping and the difficulties and seals were repeated after each step.

The aforementioned drawbacks are eliminated by a chamber body according to the invention, characterized in that it comprises a measuring chamber connected both to the detector and to the pump, the measuring chamber being hermetically separated from the peripheral auxiliary channel, sealed against the atmosphere and associated with the pump.

A practical embodiment of the chamber body according to the invention is shown schematically in the drawing.

199 048

199 048

As can be seen, the chamber body 2 is applied to the surface of the test part 2 · 7 of the body 2, a measuring chamber 2 is formed in the middle ^and a circumferential auxiliary channel 6 is formed around it. is hermetically sealed from the atmosphere outside seal 4. the inner seal 1 2 £ outer seal between the sealing surface of the test part 2 ^{and the} sealing surfaces of the body 2 * Measuring chamber 2 by ^e connected via the throttle valve 18 to the detector 2 zkuěebního media and Preem epojovací valve 12 and The peripheral duct 6 is connected via a shut-off valve 11 to the vacuum pump 8. A first gauge 2 of the vacuum gauge 17 is connected to the branch between the peripheral auxiliary channel 8 and the shut-off valve 22. On the branch between the measuring chamber 2 ^{and the} throttle 18 gauge 10 of vacuum gauge 17. ^{On the} opposite side, tested sat Part 2> Is a chamber 24, which is connected by a gas hose to a pressure reducer 22 connected to a cylinder 24 ^{with a} test medium, is attached to the test connection 22 «. Body 2 Is applied to the component to be tested so that the measuring cell 2 j ® above the test connection 22 ·

When detecting the leak of the test joint 11, the body 2 is placed on the cleaned surface of the test component 2 so that its measuring chamber 6 covers the test joint 13.

Then, the shut-off valve 11 and the connection valve 22 are opened, the vacuum gauge 17 is activated, and the vacuum pump 8 begins to reduce the pressure in both the measuring chamber 6 and the peripheral auxiliary channel 8. At atmospheric pressure, the body 2 is pressed against the surface of the component 2, compressing both the inner seal 4 and the outer seal 4 as necessary. After reaching the required vacuum, the size of which is measured by the vacuum gauge 17 and its gauges 8, 10 ^and the valve 12 slowly opens the choke valve 18. Now that the peripheral auxiliary channel is evacuated by the vacuum pump 8 and the vacuum therein and is measured by the first gauge 8 of the vacuum gauge 21, a pressure equilibrium is established in the peripheral auxiliary channel. The measuring chamber ae is now sucked out only by the test medium detector 2 and the vacuum in it is measured by the second gauge 10 of the vacuum gauge 17. Since the vacuum in the circumferential auxiliary channel £ ee differs from the vacuum in the measuring chamber? J practically negligible. Tlm completes the preparation part of the test and at the next self-check of the tightness of the tested connection 13, a chamber 14 is connected to it from the other side connected through a gas hose and a pressure regulator 15 to a pressure cylinder 16 with a test handle. The test medium is introduced into the chamber 24 P ° with a constant small overpressure (about 100 Pa), which slowly moves along the length of the test connection 22 · ^{7 in} case of leakage the test medium is sucked into the measuring chamber 6 and from there into the detector 2. reacts with a proportional electrical signal. The test medium, which diffuses into the atmosphere during testing and which penetrates the imperfection of the outer seal 4 ^{into the} peripheral auxiliary channel 4, is sucked out of it by a vacuum pump 6 without affecting the measurement itself.

The device according to the invention is intended for tightness tests of joints of plates, sheets and shells, whether planar or cylindrical, whose surface is sufficiently suited for the use of the suction chamber

199 048 straight and smooth. The chambers may be circular, square or rectangular in shape and may be both planar and shaped. Smaller joints are tested at once, longer joints are tested by stepping. The device can also be used as a lid for some vacuum devices, especially where the tightness of the connection needs to be checked after each closure. The types of vacuum pumps and detectors, their connection as well as the methods of testing are diverse and are chosen according to the size and character of the tested component, the required sensitivity of the testing and the layout of the workplace.

Claims (1)

SUBJECT OF THE INVENTION Chamber for vacuum leak testing, characterized in that a measuring chamber (5) is formed therein, connected both to the detector (7) and to the vacuum pump (8), the measuring chamber (5) being hermetically separated from the peripheral auxiliary channel ( 6), sealed against the atmosphere and associated with the pump (8).