METHOD OF TIGHTNESS TEST OF ARTICLES Russian patent published in 1997 - IPC

FIELD: tightness test of articles with semi-permeable coat partially applied on outer surface. SUBSTANCE: space between outer surface of article and semi-permeable coat is formed. Article is placed into closed shell, calibrated flow of test gas is supplied into closed shell, change of concentration of test gas in closed shell is measured and supply of calibrated flow of test gas into shell is stopped. Then calibrated flow of test gas is supplied into space between outer surface of article and semi-permeable coat, change of concentration of test gas in closed shell is measured and supply of calibrated flow of test gas into space between outer surface of article and semi-permeable coat is stopped. Article is filled with test gas, change of concentration of test gas in closed shell is measured and degree of tightness of article is judged by relations of values of change of concentration of test gas in closed shell with filled article and during supply of calibrated flow of test gas into closed shell and into space between outer surface of article and semi-permeable coat. Time intervals τ₁ from moment of supply of calibrated flow of test gas into closed shell, τ₂ from moment of supply of calibrated of test gas into space between outer surface of article and semi-permeable coat and τ_art from moment of filling of article with test gas to corresponding moment of stabilization of changes of concentrations of test gas in closed shell are measured. Leakage is detected by realization of relation τ_art≅ τ₁ on sections free from coat and of relation τ₁< τ_art≅ τ₂ on coated sections. EFFECT: increased authenticity of method, expanded application field. 1 dwg