METHOD AND DEVICE FOR LEAKAGE CHECK OF THE LIQUID-PROPELLANT ROCKETS CYLINDER COURSES Russian patent published in 2017 - IPC G01M3/20 

FIELD: testing equipment.

SUBSTANCE: position the product (2), the volume of which is sealed at the ends, in the upright position of the axial line on the mounting table (1) of the testing vacuum chamber (3). The controlling gas pressure supply manifold is connected to the internal volume of the product (2). The bell jar of the testing vacuum chamber (3) is mounted on the mounting table (1) and sealed. The ambient air is removed from the testing chamber (3) volume. The product (2) is loaded with testing gas exessive pressure. The testing gas leakage into the testing chamber (3) volume is recorded and measured by mass spectrometer leak detector (7). The through micro leakiness location area on the product surface is determined additionally to the total leakage measuring of the controlled product (2). For this purpose the annular local chamber (8) is used, the volume of which communicates by the flexible vacuum hose (11) with the vacuum system of the mass spectrometer leak detector (7). Sequentially step by step move the local chamber (8) along the entire lateral cylindrical surface of the product (2), creating the sealed connection with its surface after each step. Record the readings of mass spectrometer leak detector (7). Determine the annular sealing area of the defect location on the product surface (2). At that the volume formed by the annular chamber (8), nominally is divided along its perimeter to the equal control shares in the even amount. In order to determine the sealing defect location under the perimeter of the annular chamber (8), disconnect the vacuum pumping system of testing (3) and a local (8) chambers. Then produce the ambient air filling in the testing chamber (3) volume and the clean dry air into the local volume chamber (8) upto the atmospheric pressure, while keeping the excess testing pressure of the control gas in the controlled product volume (2). Performing the holding for a certain time, on expiry of which provide the air circulation in the local volume chamber (8) in the direction of the connecting branch of flexible control vacuum pipe (11) with the known volum flow. At the same time fill in the clean dry air with the same volume flow through the flexible pipeline (16), connected to the local chamber volume (8) at the point opposite the connection of the flexible control vacuum pipe (11). The coordinate L∂ of the defect location under the perimeter of the local chamber (8) is determined by the time value of the mass spectrometer leak detector (7) maximum signal setting to the helium flow, entering the eak detector inlet system l through the probe (30), connected to the control vacuum pipe (11). To determine under which symmetrically located share of local annular chamber volume (8) there is the defective sealing, after the air circulation in the local chamber volume (8) finishing, produce the repeated holding within the same time. Then control the content of actually accumulated in the local chamber volume (8) of helium, when it arrives from the micro leakiness by survey through two symmetric control branches(24) on the surface of the local chamber, located at the distance along the perimeter of the annular chamber (8), close to the value L∂, from the left and right from the connection point of control vacuum pipe (11) with the local volume chamber (8).

EFFECT: increased sensitivity and reliability of leakage check, reduction of the labour cost and time to search the leakage defects, improvement of test performance.

3 cl, 1 dwg