SU1037097A1 - Method of checking leak-proofness of large-size elongated articles - Google Patents

Abstract

METHOD OF CONTROL OF TIGHTNESS OF LARGE-SIZED LONG-DIMENSIONAL PRODUCTS, consisting in that the product is placed in a vacuum chamber with a leak detector and a control leak attached to it, a vacuum chamber; A leak detector is calibrated, calibrated at the checkpoint leak, the product is filled with a test gas, and the leaktightness of the product is judged by comparing the leak detector's signals from the test leak and the product, characterized in that in order to also localize the leakage area of the product control leaks along the chamber length, calibration is carried out successively for each control leak by recording the time of occurrence and magnitude of the leak detector signal, in addition, the time of occurrence and the value of the signal after filling the product with the test gas, and the leakage zone is determined by the non ratio of the time of the occurrence of the leak detector signal to it. About CAD 1 about: o h

Description

The invention relates to leak tests and can be used to localize leaking zones in the shells of large-sized long products while also determining their total leakage.

A known method for determining leaks, concludes with that the product is pressurized with a test gas, placed in a vacuum chamber 5 by means of a sensor, the total leakage is determined, and leak zones are detected by changing the cocTaBia of the gas medium

II ..

The disadvantage of the known method is the need to heat separate parts of the surface of the products, which complicates and delays the control process.

The closest to the invention in technical essence and the achieved effect is the method of monitoring the tightness of large-sized long products, which means that the product is placed in a vacuum chamber with a leak detector and a control leak attached to it, the chamber is evacuated, the leak detector is calibrated. the test leak, the product is filled with the test gas and the product is more tightly judged by comparing the leak detector signals from the test leak and from the product 2 J.

The disadvantage of this method is the impossibility of localizing the leakage zone ..;

The aim of the invention is to provide also localization of the leakage zone of the product.

This goal is achieved by the fact that, according to the method of testing tightness, large-sized long-length products, which consists in placing the product in a vacuum chamber with a leak and a control leak attached to it, vacuuming the chamber, calibrating the leak detector for the test leak, and filling the product with a test gas , and the product’s tightness is judged by comparing the leak detector signals from the test leak and the product, several test leaks are installed along the length of the chamber, the calibration is carried out For each test leak, by registering the time of occurrence and magnitude of the leak detector signal, in addition, the time of occurrence and magnitude of the igniter after filling the HbiM product with the gas is recorded, and the leakage zone is determined by the amount of leakage time of the leak detector signal: magnitude.

I on. 1 shows a vacuum circuit for carrying out the method; on

FIG. 2 shows the recording of the change in the signal of the leak detector during the filling of the product with the test gas and during its bleeding) in FIG. 3 - graphs of the change in the ratio of the time of occurrence of a leak detector signal to its magnitude depending on the location of test leaks along the length of the chamber L for various values of leaks.

The method is carried out as follows.

Product 1 is placed in chamber 2. The chamber is sealed and pumped out with high-vacuum aggregates 3 and mechanical pumps 4. Calibration is performed — each of the control leaks 5 are opened and / or the signals of the leak detector c. 6 are recorded on the self-recording potentiometer tape 7, similar to that shown in FIG. . 2. Calibration is repeated several times, each time using test leaks 5 with a different value of the control gas flow. Test product 1 is filled with test gas from bench 8 and again a record of leakage leakage is obtained by pouring potentiometer 7. On the base In the obtained records, the values of T / rf are determined — the ratio of the time of occurrence of the leak detector signal to its value (the slope of the straight line section of the curve, similar to that shown in Fig. 2}

"Wax omin and ij-, - ratios

s.K

d.i

control leaks 5 to the values of the set signals i ((the leaks of the driver b are correspondingly close to the tschechuchatel b leaks 5 and most remote from him during calibration, as well as the values of

t -. .-, - established sig-tech

Leaked the leak 6 when filling product 1 with the control gas. Contributorshiox

melt the values of m: 5L-s / „,., and the leak flow

According to received values

.

T / oL builds a family of graphs similar to that shown in FIG. 3. Next, on the ordinate axis of the graphs obtained, they set aside the value

The tr of the obtained points are drawn straight, parallel to the abscissa axis, to the intersection with the curves corresponding to the values

Of those "" "

points of intersection lower the perpendiculars on the abscissa axis, noting, ki, 11 Tspoi segment Chn, 4. - defines the zone of leaktightness.

310370974

The application of the invention allows an increase in the possible combination of processes to increase the productivity of the tests, determine the total leakage and reduce the flow rate of the control gas for and localize the leakage zone.

i f-tnia

Claims (2)

METHOD FOR LEAKAGE TESTING OF LARGE-SIZED LONG-DIMENSIONAL PRODUCTS, which consists in the fact that the product is placed in a vacuum chamber with a leak detector and a control leak connected to it, the vacuum chamber; they dig, calibrate the leak detector according to; 2Y02Sh \ test leak, the product is filled with control gas, and the tightness of the product is judged by comparing the leak detector signals from the control leak and the product, characterized in that, in order to ensure also the localization of the leak zone of the product, several control leaks are installed along the length of the chamber, calibration is carried out sequentially for each control leak by registering the appearance time and magnitude of the leak detector signal, in addition, the appearance time and magnitude of the signal after filling the counter product are recorded lnym gas leakage as determined by Aeon volich unrelated appearance of the signal time of the leak detector to its value.