METHOD OF FUEL TIGHTNESS TESTING OF ARTICLES Russian patent published in 1994 - IPC

FIELD: testing spacecrafts for fluid tightness. SUBSTANCE: method involves the steps of: placing an article to be tested in a vacuum chamber, communicating the vacuum chamber with a leak detector, evacuating the leak detector through the vacuum chamber till reaching a working pressure in the vacuum chamber corresponding to a maximum sensitivity of the leak detector with the aid of evacuating equipment, disconnecting the vacuum chamber and leak detector. The method is characterized in that prior to feeding a test gas calibrated flow into the vacuum chamber and prior to filling the article with test gas the vacuum chamber is evacuated to a predetermined pressure less than a working one. After feeding the test gas calibrated flow and after filling he article with test gas the vacuum chamber and evacuating equipment are disconnected. At the moment of reaching the working pressure in the vacuum chamber the vacuum chamber is in communication with the leak detector. Maximum increments in readings of the leak detector from calibrated flow and from the article are measured. The information on leak in the article is derived from the difference of measured increments. EFFECT: widened range of leaks to be measured towards leaser leaks.