RU1837190C - Method for testing articles for tightness - Google Patents

Description

(L

with

: The invention relates to a researcher; technique and can be used to measure leaks in products. working under internal devel- iment.

: The aim of the invention is to increase the reliability of product testing. I Refilling the refueling line just before the initial pressure in the product is carried out to compensate for the | what portion of gas that was lost; when the filling line communicates with the atmosphere surrounding the product, i. i. reducing the conditions for measuring the final pressure i of the control gas in the product to; initial conditions by mass of gas. The method is carried out using the device depicted in; drawing.

The controlled product 1 includes a filling valve 2, to which a filling line 3 with a pressure gauge 4, a drain valve 5 and a filling unit b is connected. The initial position of valve 2 and valves 5, 6 is closed.

The operation of the method is as follows.

Open valve 2 and open valve 6, fill product S with control gas before operating overpressure with pressure gauge 4. Then close valve b and measure with pressure gauge 4 the initial pressure of the PK in the product. Close valve 4 and, by opening valve 5, vent excess gas pressure from the gas supply line to atmospheric pressure; valve 5 is opened in open position. After a fixed time interval Ar, open the valve 5 and, opening the valve 6. fill

G3 n

test gas supply line to a pressure of Р by a pressure gauge 4. Close valve 6, open valve 2 and measure the final pressure Рк in the product by pressure gauge 4.

The leakage value of the Oizd product is determined by the formula

V

Rn - Rk

Lg

where V is the geometric volume occupied by the gas in the product and in the filling line. The initial formula for calculating the leakage of a product (Edition) is as follows:

Rn - Rk

Ag

(1)

where / ed the geometric volume occupied by the gas in the product;

PH

1

initial and final pressure

in the product at the beginning and at the end of the time interval Dt.

In the case under consideration, at the beginning and at the end of the time interval Дт, the gas mass of the filling line equal to / mRn is connected to the gas mass of the product, where VM is the geometric volume occupied by the gas of the filling line, i.e. the initial mass of gas is (Wizd + Um) Rn, and the final mass of gas is WizdRk1 + UnRn (Wwd +

0

+ VM) PK, where Рк is the measured pressure in the product and in the filling line at the end of the time interval Лг.

Then, substituted into the formula (1) we get:

(Wizd + Um) Rn (Wizd + Um) Pk

(WizD + + UM) A

Q

5

0

5

0

Formula and shadow image A method for checking the tightness of products, which consists in filling the product with test gas through the filling line to the operating overpressure, measuring the initial pressure in the filling line connected to the product, and measuring the final pressure through the holding time interval in the filling line and by the difference in the measured pressures, the leakage of the product, the capacity and the fact that, in order to increase the reliability of testing products with a filling valve in the filling master are judged After measuring the initial pressure, close the filling valve and reduce the pressure in the filling line to atmospheric, and before measuring the final pressure, fill the filling line with gas to a pressure equal to the initial pressure and open the filling valve.